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Atlas of Anatomy
Fourth Edition
Edited by
Anne M. Gilroy, MA
Professor Emeritus
Department of Radiology
University of Massachusetts Medical School
Worcester, Massachusetts
Brian R. MacPherson, PhD
Professor and Vice Chair
Department of Neuroscience
University of Kentucky College of Medicine
Lexington, Kentucky
Jamie C. Wikenheiser, PhD
Associate Professor
Department of Anatomy and Neurobiology
UC Irvine School of Medicine
Irvine, California
Based on the work of
Michael Schuenke, MD, PhD
Institute of Anatomy
Christian Albrechts University Kiel
Kiel, Germany
Erik Schulte, MD
Department of Functional and Clinical Anatomy
University Medicine
Johannes Gutenberg University
Mainz, Germany
Udo Schumacher, MD, FRCPath, CBiol, FSB, DSc
Institute of Anatomy and Experimental Morphology
Center for Experimental Medicine
University Cancer Center
University Medical Center Hamburg-Eppendorf
Hamburg, Germany
Illustrations by
Markus Voll
Karl Wesker
2113 illustrations
Thieme
New York · Stuttgart · Delhi · Rio de Janeiro
Illustrators: Markus Voll and Karl Wesker
Development Editor: Judith Tomat
Production Editor: Barbara Chernow
Compositor: Carol Pierson, Chernow Editorial Services, Inc.
Library of Congress Cataloging-in-Publication Data
Names: Gilroy, Anne M., editor. | MacPherson, Brian R., editor. |
Wikenheiser, Jamie C., editor. | Voll, Markus M., illustrator. | Wesker,
Karl, illustrator. | Schünke, Michael. Thieme atlas of anatomy.
Title: Atlas of anatomy / edited by Anne M. Gilroy, Brian R. MacPherson,
Jamie C. Wikenheiser ; based on the work of Michael Schuenke, Erik
Schulte, Udo Schumacher ; illustrations by Markus Voll, Karl Wesker.
Other titles: Atlas of anatomy (Gilroy)
Description: Fourth edition. | New York : Thieme, [2020] | Includes
index. | Summary: “An updated atlas that provides a clear, accurate,
and fully illustrated guide to human anatomy”— Provided by
publisher.
Identifiers: LCCN 2019058797 (print) | LCCN 2019058798 (ebook) |
ISBN 9781684202034 (paperback) | ISBN 9781684202041 (ebook)
Subjects: MESH: Anatomy | Atlas
Classification: LCC QM25 (print) | LCC QM25 (ebook) | NLM QS 17 |
DDC 611.0022/3—dc23
LC record available at https://lccn.loc.gov/2019058797
LC ebook record available at https://lccn.loc.gov/2019058798
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Dedications
To the thousands of former students who have populated every specialty and
migrated to every corner of this country, while dedicating their careers to making
life better for thousands more. I am inspired by their empathy and kindness, and
grateful to have been a small part of their journey.
And as always, to Colin and Bryan.
Anne M. Gilroy
To my friend and mentor Dr. Ken McFadden, who was responsible for my early
training in gross anatomy and was a role model for success in teaching. I deeply
appreciate the feedback I have received over the past 40 plus years from the
thousands of students I have taught and who have made me an even better
teacher. However, none of the success I have enjoyed in my life would have been
possible without the constant support, assistance, and encouragement of my late
wife, Cynthia Long.
Brian R. MacPherson
To my wife Jen and my son Quinn.
Jamie C. Wikenheiser
Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xiii
Foreword. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xiv
Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xv
Preface to the First Edition. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xvii
Spinal Cord . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Spinal Cord Segments & Spinal Nerves . . . . . . . . . . . . . . . . . .
Arteries & Veins of the Spinal Cord . . . . . . . . . . . . . . . . . . . . .
Neurovascular Topography of the Back . . . . . . . . . . . . . . . . . .
40
42
44
46
Table of Contents
Table of Contents
5 Sectional & Radiographic Anatomy
Radiographic Anatomy of the Back (I) . . . . . . . . . . . . . . . . . . . 48
Radiographic Anatomy of the Back (II). . . . . . . . . . . . . . . . . . . 50
Back
1 Surface Anatomy
Surface Anatomy. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
2 Bones, Ligaments & Joints
Vertebral Column: Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Vertebral Column: Elements . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Cervical Vertebrae . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Thoracic & Lumbar Vertebrae . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Sacrum & Coccyx . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Intervertebral Disks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Joints of the Vertebral Column: Overview . . . . . . . . . . . . . . . . 16
Joints of the Vertebral Column: Craniovertebral Region . . . . . 18
Vertebral Ligaments: Overview & Cervical Spine . . . . . . . . . . 20
Vertebral Ligaments: Thoracolumbar Spine . . . . . . . . . . . . . . 22
3 Muscles
Muscles of the Back: Overview . . . . . . . . . . . . . . . . . . . . . . . . .
Intrinsic Muscles of the Cervical Spine . . . . . . . . . . . . . . . . . . .
Intrinsic Muscles of the Back . . . . . . . . . . . . . . . . . . . . . . . . . .
Muscle Facts (I) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Muscle Facts (II) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Muscle Facts (III) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
24
26
28
30
32
34
4 Neurovasculature
Arteries & Veins of the Back . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Nerves of the Back . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Thorax
6 Surface Anatomy
Surface Anatomy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
7 Thoracic Wall
Thoracic Skeleton . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Sternum & Ribs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Joints of the Thoracic Cage . . . . . . . . . . . . . . . . . . . . . . . . . . .
Thoracic Wall Muscle Facts . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Diaphragm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Neurovasculature of the Diaphragm . . . . . . . . . . . . . . . . . . . .
Arteries & Veins of the Thoracic Wall . . . . . . . . . . . . . . . . . . . .
Nerves of the Thoracic Wall . . . . . . . . . . . . . . . . . . . . . . . . . . .
Neurovascular Topography of the Thoracic Wall . . . . . . . . . . .
Female Breast . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Lymphatics of the Female Breast . . . . . . . . . . . . . . . . . . . . . . .
56
58
60
62
64
66
68
70
72
74
76
8 Thoracic Cavity
Divisions of the Thoracic Cavity . . . . . . . . . . . . . . . . . . . . . . . .
Arteries of the Thoracic Cavity . . . . . . . . . . . . . . . . . . . . . . . . .
Veins of the Thoracic Cavity . . . . . . . . . . . . . . . . . . . . . . . . . . .
Lymphatics of the Thoracic Cavity . . . . . . . . . . . . . . . . . . . . . .
Nerves of the Thoracic Cavity . . . . . . . . . . . . . . . . . . . . . . . . .
78
80
82
84
86
vii
Table of Contents
9 Mediastinum
Mediastinum: Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88
Mediastinum: Structures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
Heart: Functions & Relations . . . . . . . . . . . . . . . . . . . . . . . . . . 92
Pericardium . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94
Heart: Surfaces & Chambers . . . . . . . . . . . . . . . . . . . . . . . . . . 96
Heart: Valves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
Arteries & Veins of the Heart . . . . . . . . . . . . . . . . . . . . . . . . . 100
Conduction & Innervation of the Heart . . . . . . . . . . . . . . . . . 102
Pre- & Postnatal Circulation . . . . . . . . . . . . . . . . . . . . . . . . . . 104
Esophagus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
Neurovasculature of the Esophagus . . . . . . . . . . . . . . . . . . . 108
Lymphatics of the Mediastinum . . . . . . . . . . . . . . . . . . . . . . . 110
112
114
116
118
120
122
124
126
128
11 Sectional & Radiographic Anatomy
Sectional Anatomy of the Thorax . . . . . . . . . . . . . . . . . . . . . .
Radiographic Anatomy of the Thorax (I). . . . . . . . . . . . . . . . .
Radiographic Anatomy of the Thorax (II). . . . . . . . . . . . . . . .
Radiographic Anatomy of the Thorax (III). . . . . . . . . . . . . . . .
130
132
134
136
Abdomen
12 Surface Anatomy
Surface Anatomy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140
13 Abdominal Wall
Bony Framework for the Abdominal Wall . . . . . . . . . . . . . . . 142
Muscles of the Anterolateral Abdominal Wall . . . . . . . . . . . . 144
viii
146
148
150
152
154
14 Abdominal Cavity & Spaces
Divisions of the Abdominopelvic Cavity . . . . . . . . . . . . . . . .
Peritoneum, Mesenteries & Omenta . . . . . . . . . . . . . . . . . . .
Mesenteries & Peritoneal Recesses . . . . . . . . . . . . . . . . . . . .
Lesser Omentum & Omental Bursa . . . . . . . . . . . . . . . . . . . .
Mesenteries & Posterior Abdominal Wall. . . . . . . . . . . . . . . .
156
158
160
162
164
15 Internal Organs
10 Pulmonary Cavities
Pulmonary Cavities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Pleura: Subdivisions, Recesses & Innervation . . . . . . . . . . . .
Lungs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Bronchopulmonary Segments of the Lungs . . . . . . . . . . . . .
Trachea & Bronchial Tree . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Respiratory Mechanics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Pulmonary Arteries & Veins . . . . . . . . . . . . . . . . . . . . . . . . . .
Neurovasculature of the Tracheobronchial Tree . . . . . . . . . .
Lymphatics of the Pleural Cavity . . . . . . . . . . . . . . . . . . . . . .
Rectus Sheath & Posterior Abdominal Wall . . . . . . . . . . . . . .
Abdominal Wall Muscle Facts . . . . . . . . . . . . . . . . . . . . . . . . .
Inguinal Region & Canal . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Inguinal Region & Inguinal Hernias. . . . . . . . . . . . . . . . . . . . .
Scrotum & Spermatic Cord . . . . . . . . . . . . . . . . . . . . . . . . . . .
Stomach . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Duodenum . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Jejunum & Ileum . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Cecum, Appendix & Colon . . . . . . . . . . . . . . . . . . . . . . . . . . .
Liver: Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Liver: Lobes & Segments . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Gallbladder & Bile Ducts . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Pancreas & Spleen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Kidneys & Suprarenal Glands (I) . . . . . . . . . . . . . . . . . . . . . . .
Kidneys & Suprarenal Glands (II) . . . . . . . . . . . . . . . . . . . . . .
166
168
170
172
174
176
178
180
182
184
16 Neurovasculature
Arteries of the Abdominal Wall & Organs . . . . . . . . . . . . . . .
Abdominal Aorta & Renal Arteries . . . . . . . . . . . . . . . . . . . . .
Celiac Trunk . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Superior & Inferior Mesenteric Arteries . . . . . . . . . . . . . . . . .
Veins of the Abdominal Wall & Organs . . . . . . . . . . . . . . . . .
Inferior Vena Cava & Renal Veins . . . . . . . . . . . . . . . . . . . . . .
Portal Vein . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Superior & Inferior Mesenteric Veins . . . . . . . . . . . . . . . . . . .
Lymphatics of the Abdominal Wall & Organs . . . . . . . . . . . .
Lymph Nodes of the Posterior Abdominal Wall . . . . . . . . . . .
Lymph Nodes of the Supracolic Organs . . . . . . . . . . . . . . . . .
Lymph Nodes of the Infracolic Organs . . . . . . . . . . . . . . . . . .
Nerves of the Abdominal Wall . . . . . . . . . . . . . . . . . . . . . . . .
Autonomic Innervation: Overview . . . . . . . . . . . . . . . . . . . . .
Autonomic Innervation & Referred Pain. . . . . . . . . . . . . . . . .
Innervation of the Foregut & Urinary Organs . . . . . . . . . . . .
Innervation of the Intestines . . . . . . . . . . . . . . . . . . . . . . . . .
186
188
190
192
194
196
198
200
202
204
206
208
210
212
214
216
218
17 Sectional & Radiographic Anatomy
Sectional Anatomy of the Abdomen . . . . . . . . . . . . . . . . . . . 220
Radiographic Anatomy of the Abdomen (I). . . . . . . . . . . . . . 222
Radiographic Anatomy of the Abdomen (II). . . . . . . . . . . . . . 224
23 Sectional & Radiographic Anatomy
Pelvis &
Perineum
Table of Contents
Sectional Anatomy of the Pelvis & Perineum. . . . . . . . . . . . . 286
Radiographic Anatomy of the Female Pelvis. . . . . . . . . . . . . 288
Radiographic Anatomy of the Male Pelvis . . . . . . . . . . . . . . . 290
18 Surface Anatomy
Surface Anatomy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 228
19 Bones, Ligaments & Muscles
Pelvic Girdle. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Female & Male Pelvis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Female & Male Pelvic Measurements . . . . . . . . . . . . . . . . . . .
Pelvic Ligaments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Muscles of the Pelvic Floor & Perineum . . . . . . . . . . . . . . . . .
Pelvic Floor & Perineal Muscle Facts. . . . . . . . . . . . . . . . . . . .
230
232
234
236
238
240
20 Spaces
Contents of the Pelvis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 242
Peritoneal Relationships . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 244
Pelvis & Perineum . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 246
21 Internal Organs
Rectum & Anal Canal. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Ureters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Urinary Bladder & Urethra . . . . . . . . . . . . . . . . . . . . . . . . . . .
Overview of the Genital Organs . . . . . . . . . . . . . . . . . . . . . . .
Uterus & Ovaries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Ligaments & Fascia of the Deep Pelvis . . . . . . . . . . . . . . . . . .
Vagina . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Female External Genitalia . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Penis, Testis & Epididymis . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Male Accessory Sex Glands. . . . . . . . . . . . . . . . . . . . . . . . . . .
248
250
252
254
256
258
260
262
264
266
22 Neurovasculature
Overview of the Blood Supply to Pelvic Organs & Wall . . . . .
Arteries & Veins of the Male Pelvis . . . . . . . . . . . . . . . . . . . . .
Arteries & Veins of the Female Pelvis . . . . . . . . . . . . . . . . . . .
Arteries & Veins of the Rectum & External Genitalia . . . . . . .
Lymphatics of the Pelvis . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Lymph Nodes of the Genitalia. . . . . . . . . . . . . . . . . . . . . . . . .
Autonomic Innervation of the Genital Organs. . . . . . . . . . . .
Autonomic Innervation of the Urinary Organs
& Rectum. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Neurovasculature of the Male & Female Perineum . . . . . . . .
268
270
272
274
276
278
280
282
284
Upper Limb
24 Surface Anatomy
Surface Anatomy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 294
25 Shoulder & Arm
Bones of the Upper Limb . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Clavicle & Scapula . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Humerus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Joints of the Shoulder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Joints of the Shoulder: Glenohumeral Joint . . . . . . . . . . . . . .
Subacromial Space & Bursae . . . . . . . . . . . . . . . . . . . . . . . . .
Anterior Muscles of the Shoulder & Arm (I) . . . . . . . . . . . . . .
Anterior Muscles of the Shoulder & Arm (II) . . . . . . . . . . . . .
Posterior Muscles of the Shoulder & Arm (I) . . . . . . . . . . . . .
Posterior Muscles of the Shoulder & Arm (II) . . . . . . . . . . . . .
Muscle Facts (I) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Muscle Facts (II) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Muscle Facts (III) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Muscle Facts (IV) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
296
298
300
302
304
306
308
310
312
314
316
318
320
322
26 Elbow & Forearm
Radius & Ulna . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Elbow Joint . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Ligaments of the Elbow Joint . . . . . . . . . . . . . . . . . . . . . . . . .
Radioulnar Joints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Muscles of the Forearm: Anterior Compartment . . . . . . . . .
Muscles of the Forearm: Posterior Compartment . . . . . . . . .
Muscle Facts (I) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Muscle Facts (II) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Muscle Facts (III) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
324
326
328
330
332
334
336
338
340
27 Wrist & Hand
Bones of the Wrist & Hand . . . . . . . . . . . . . . . . . . . . . . . . . . . 342
Carpal Bones . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 344
Joints of the Wrist & Hand . . . . . . . . . . . . . . . . . . . . . . . . . . . 346
ix
Table of Contents
Ligaments of the Hand . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Ligaments & Compartments of the Wrist . . . . . . . . . . . . . . .
Ligaments of the Fingers . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Muscles of the Hand: Superficial & Middle Layers . . . . . . . . .
Muscles of the Hand: Middle & Deep Layers . . . . . . . . . . . . .
Dorsum of the Hand . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Muscle Facts (I) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Muscle Facts (II) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
348
350
352
354
356
358
360
362
28 Neurovasculature
Arteries of the Upper Limb . . . . . . . . . . . . . . . . . . . . . . . . . . .
Veins & Lymphatics of the Upper Limb . . . . . . . . . . . . . . . . .
Nerves of the Upper Limb: Brachial Plexus . . . . . . . . . . . . . .
Supraclavicular Branches & Posterior Cord . . . . . . . . . . . . . .
Posterior Cord: Axillary & Radial Nerves . . . . . . . . . . . . . . . .
Medial & Lateral Cords . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Median & Ulnar Nerves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Superficial Veins & Nerves of the Upper Limb . . . . . . . . . . . .
Posterior Shoulder & Arm . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Anterior Shoulder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Axilla . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Anterior Arm & Cubital Region . . . . . . . . . . . . . . . . . . . . . . . .
Anterior & Posterior Forearm . . . . . . . . . . . . . . . . . . . . . . . . .
Carpal Region . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Palm of the Hand . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Dorsum of the Hand . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
364
366
368
370
372
374
376
378
380
382
384
386
388
390
392
394
396
398
400
402
404
Lower Limb
30 Surface Anatomy
Surface Anatomy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 408
31 Hip & Thigh
Bones of the Lower Limb . . . . . . . . . . . . . . . . . . . . . . . . . . . . 410
Femur . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 412
Hip Joint: Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 414
x
416
418
420
422
424
426
428
430
32 Knee & Leg
29 Sectional & Radiographic Anatomy
Sectional Anatomy of the Upper Limb. . . . . . . . . . . . . . . . . .
Radiographic Anatomy of the Upper Limb (I). . . . . . . . . . . . .
Radiographic Anatomy of the Upper Limb (II). . . . . . . . . . . .
Radiographic Anatomy of the Upper Limb (III). . . . . . . . . . . .
Radiographic Anatomy of the Upper Limb (IV) . . . . . . . . . . .
Hip Joint: Ligaments & Capsule . . . . . . . . . . . . . . . . . . . . . . .
Anterior Muscles of the Hip, Thigh & Gluteal Region (I) . . . .
Anterior Muscles of the Hip, Thigh & Gluteal Region (II) . . .
Posterior Muscles of the Hip, Thigh & Gluteal Region (I) . . .
Posterior Muscles of the Hip, Thigh & Gluteal Region (II) . . .
Muscle Facts (I) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Muscle Facts (II) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Muscle Facts (III) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Tibia & Fibula . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Knee Joint: Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Knee Joint: Capsule, Ligaments & Bursae . . . . . . . . . . . . . . .
Knee Joint: Ligaments & Menisci . . . . . . . . . . . . . . . . . . . . . .
Cruciate Ligaments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Knee Joint Cavity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Muscles of the Leg: Anterior & Lateral Compartments . . . . .
Muscles of the Leg: Posterior Compartment . . . . . . . . . . . . .
Muscle Facts (I) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Muscle Facts (II) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
432
434
436
438
440
442
444
446
448
450
33 Ankle & Foot
Bones of the Foot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Joints of the Foot (I) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Joints of the Foot (II) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Joints of the Foot (III) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Ligaments of the Ankle & Foot . . . . . . . . . . . . . . . . . . . . . . . .
Plantar Vault & Arches of the Foot . . . . . . . . . . . . . . . . . . . . .
Muscles of the Sole of the Foot . . . . . . . . . . . . . . . . . . . . . . .
Muscles & Tendon Sheaths of the Foot . . . . . . . . . . . . . . . . .
Muscle Facts (I) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Muscle Facts (II) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
452
454
456
458
460
462
464
466
468
470
34 Neurovasculature
Arteries of the Lower Limb . . . . . . . . . . . . . . . . . . . . . . . . . . . 472
Veins & Lymphatics of the Lower Limb . . . . . . . . . . . . . . . . . 474
Lumbosacral Plexus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 476
Nerves of the Lumbar Plexus . . . . . . . . . . . . . . . . . . . . . . . . . 478
Nerves of the Lumbar Plexus: Obturator & Femoral Nerves . 480
Nerves of the Sacral Plexus . . . . . . . . . . . . . . . . . . . . . . . . . . . 482
Nerves of the Sacral Plexus: Sciatic Nerve . . . . . . . . . . . . . . . 484
Superficial Nerves & Veins of the Lower Limb . . . . . . . . . . . . 486
Topography of the Inguinal Region . . . . . . . . . . . . . . . . . . . . 488
Topography of the Gluteal Region . . . . . . . . . . . . . . . . . . . . . 490
Topography of the Anterior, Medial & Posterior Thigh . . . . . 492
Topography of the Posterior Compartment
of the Leg & Foot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 494
Topography of the Lateral & Anterior Compartments
of the Leg & Dorsum of the Foot . . . . . . . . . . . . . . . . . . . . 496
Topography of the Sole of the Foot . . . . . . . . . . . . . . . . . . . . 498
35 Sectional & Radiographic Anatomy
Sectional Anatomy of the Lower Limb . . . . . . . . . . . . . . . . . . 500
Radiographic Anatomy of the Lower Limb (I) . . . . . . . . . . . . 502
CN V: Trigeminal Nerve . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CN VII: Facial Nerve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CN VIII: Vestibulocochlear Nerve . . . . . . . . . . . . . . . . . . . . . .
CN IX: Glossopharyngeal Nerve . . . . . . . . . . . . . . . . . . . . . . .
CN X: Vagus Nerve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CN XI & XII: Accessory & Hypoglossal Nerves . . . . . . . . . . . .
Autonomic Innervation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
566
568
570
572
574
576
578
41 Neurovasculature of the Skull & Face
Head & Neck
36 Surface Anatomy
Surface Anatomy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 512
37 Neck
Muscle Facts (I) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Muscle Facts (II) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Muscle Facts (III) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Arteries & Veins of the Neck . . . . . . . . . . . . . . . . . . . . . . . . . .
Lymphatics of the Neck . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Innervation of the Neck . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Larynx: Cartilage & Structure . . . . . . . . . . . . . . . . . . . . . . . . .
Larynx: Muscles & Levels . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Neurovasculature of the Larynx, Thyroid & Parathyroids . . .
Topography of the Neck: Regions & Fascia . . . . . . . . . . . . . .
Topography of the Anterior Cervical Region . . . . . . . . . . . . .
Topography of the Anterior & Lateral Cervical Regions . . . .
Topography of the Lateral Cervical Region . . . . . . . . . . . . . .
Topography of the Posterior Cervical Region . . . . . . . . . . . .
514
516
518
520
522
524
526
528
530
532
534
536
538
540
38 Bones of the Head
Anterior & Lateral Skull . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Posterior Skull & Calvaria . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Base of the Skull . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Neurovascular Pathways Exiting or Entering
the Cranial Cavity. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Ethmoid & Sphenoid Bones . . . . . . . . . . . . . . . . . . . . . . . . . .
542
544
546
548
550
39 Muscles of the Skull & Face
Muscles of Facial Expression & of Mastication . . . . . . . . . . . .
Muscle Origins & Insertions on the Skull . . . . . . . . . . . . . . . .
Muscle Facts (I) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Muscle Facts (II) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
552
554
556
558
40 Cranial Nerves
Cranial Nerves: Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . 560
CN I & II: Olfactory & Optic Nerves . . . . . . . . . . . . . . . . . . . . 562
CN III, IV & VI: Oculomotor, Trochlear & Abducent Nerves . . . 564
Innervation of the Face . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Arteries of the Head & Neck . . . . . . . . . . . . . . . . . . . . . . . . . .
External Carotid Artery: Anterior, Medial &
Posterior Branches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
External Carotid Artery: Terminal Branches . . . . . . . . . . . . . .
Veins of the Head & Neck . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Meninges . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Dural Sinuses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Topography of the Superficial Face . . . . . . . . . . . . . . . . . . . .
Topography of the Parotid Region & Temporal Fossa . . . . . .
Topography of the Infratemporal Fossa . . . . . . . . . . . . . . . . .
Neurovasculature of the Infratemporal Fossa . . . . . . . . . . . .
580
582
Table of Contents
Radiographic Anatomy of the Lower Limb (II) . . . . . . . . . . . . 504
Radiographic Anatomy of the Lower Limb (III). . . . . . . . . . . . 506
Radiographic Anatomy of the Lower Limb (IV). . . . . . . . . . . . 508
584
586
588
590
592
594
596
598
600
42 Orbit & Eye
Bones of the Orbit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Muscles of the Orbit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Neurovasculature of the Orbit . . . . . . . . . . . . . . . . . . . . . . . .
Topography of the Orbit . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Orbit & Eyelid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Eyeball . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Cornea, Iris & Lens . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
602
604
606
608
610
612
614
43 Nasal Cavity & Nose
Bones of the Nasal Cavity . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Paranasal Air Sinuses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Neurovasculature of the Nasal Cavity . . . . . . . . . . . . . . . . . .
Pterygopalatine Fossa. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
616
618
620
622
44 Temporal Bone & Ear
Temporal Bone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
External Ear & Auditory Canal . . . . . . . . . . . . . . . . . . . . . . . . .
Middle Ear: Tympanic Cavity . . . . . . . . . . . . . . . . . . . . . . . . .
Middle Ear: Ossicular Chain & Tympanic Membrane . . . . . . .
Arteries of the Middle Ear . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Inner Ear . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
624
626
628
630
632
634
45 Oral Cavity & Pharynx
Bones of the Oral Cavity . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Temporomandibular Joint . . . . . . . . . . . . . . . . . . . . . . . . . . .
Teeth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Oral Cavity Muscle Facts . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Innervation of the Oral Cavity . . . . . . . . . . . . . . . . . . . . . . . .
Tongue. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Topography of the Oral Cavity & Salivary Glands . . . . . . . . .
636
638
640
642
644
646
648
xi
Table of Contents
Tonsils & Pharynx . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 650
Pharyngeal Muscles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 652
Neurovasculature of the Pharynx . . . . . . . . . . . . . . . . . . . . . . 654
46 Sectional & Radiographic Anatomy
Sectional Anatomy of the Head & Neck (I). . . . . . . . . . . . . . .
Sectional Anatomy of the Head & Neck (II) . . . . . . . . . . . . . .
Sectional Anatomy of the Head & Neck (III). . . . . . . . . . . . . .
Sectional Anatomy of the Head & Neck (IV). . . . . . . . . . . . . .
Sectional Anatomy of the Head & Neck (V) . . . . . . . . . . . . . .
Radiographic Anatomy of the Head & Neck (I). . . . . . . . . . . .
Radiographic Anatomy of the Head & Neck (II). . . . . . . . . . .
Radiographic Anatomy of the Head & Neck (III). . . . . . . . . . .
656
658
660
662
664
666
668
670
Brain, Macroscopic Organization . . . . . . . . . . . . . . . . . . . . . .
Diencephalon . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Brainstem & Cerebellum . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Ventricles & CSF Spaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
678
680
682
684
48 Blood Vessels of the Brain
Veins & Venous Sinuses of the Brain . . . . . . . . . . . . . . . . . . . 686
Arteries of the Brain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 688
49 Functional Systems
Anatomy & Organization of the Spinal Cord. . . . . . . . . . . . . . 690
Sensory & Motor Pathways . . . . . . . . . . . . . . . . . . . . . . . . . . . 692
50 Autonomic Nervous System
Autonomic Nervous System (I): Overview . . . . . . . . . . . . . . . 694
Autonomic Nervous System (II) . . . . . . . . . . . . . . . . . . . . . . . 696
51 Sectional & Radiographic Anatomy
Sectional Anatomy of the Nervous System . . . . . . . . . . . . . . 698
Radiographic Anatomy of the Nervous System . . . . . . . . . . . 700
Brain &
Nervous System
47 Brain
Nervous System: Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . 674
Nervous System: Development . . . . . . . . . . . . . . . . . . . . . . . 676
xii
Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 703
Acknowledgments
We would like to thank the authors of the original award-winning Thieme Atlas of Anatomy three-volume series, Michael Schuenke, Erik Schulte,
and Udo Schumacher, and the illustrators, Karl Wesker and Marcus Voll, for their work over the course of many years.
We thank the many instructors, students, and translators for our non-English versions, who have taken the time to point out to us what we have
done well and brought to our attention errors, ambiguities, and new information, or have suggested how we could present a topic more effectively.
This input, combined with our experience teaching with the Atlas, have guided our work on this edition.
We cordially thank the reviewers of the third edition, especially those who provided in-depth feedback:
• Jennifer Brueckner-Collins, PhD
University of Louisville School of Medicine
Louisville, Kentucky
• Luís Otávio Carvalho de Moraes, PhD
Federal University of São Paulo
São Paulo, Brazil
• Jennifer Carr, PhD
Salem State University
Salem, Massachussetts
• F. Baker Mills IV, MS (Class of 2021)
University of South Carolina School of Medicine
Columbia, South Carolina
• C. Cem Denk, MD, PhD
Hacettepe University
Faculty of Medicine
Ankara, Turkey
• Stephen M. Novak, MD, JD
Harvard University
Cambridge, Massachusetts
• Gary J. Farkas, PhD
University of California, San Francisco School of Medicine
San Francisco, California
• Joy R. Patel (Class of 2021)
NYIT College of Osteopathic Medicine
Old Westbury, New York
• Derek Harmon, PhD
University of California, San Francisco School of Medicine
San Francisco, California
• Paisley Lynae Pauli, MHA (Class of 2021)
University of the Incarnate Word
School of Osteopathic Medicine
San Antonio, Texas
• Lindsey Kent (Class of 2020)
West Virginia School of Osteopathic Medicine
Lewisburg, West Virginia
• Guenevere Rae, MS, PhD
Tulane University School of Medicine
New Orleans, Louisiana
• Barbie Klein, PhD
University of California, San Francisco School of Medicine
San Francisco, California
• Sherese Richards, MD
The College of St. Scholastica
Duluth, Minnesota
• Nancy Lin (Class of 2021)
CUNY School of Medicine
New York, New York
• William J. Swartz, PhD
LSU Health Sciences Center
New Orleans, Louisiana
Foreword
This Atlas of Anatomy, in my opinion, is the finest single-volume atlas
of human anatomy that has ever been created. Two factors make it so:
the images and the way they have been organized.
The artists, Markus Voll and Karl Wesker, have created a new standard
of excellence in anatomical art. Their graceful use of transparency and
their sensitive representation of light and shadow give the reader an
accurate three-dimensional understanding of every structure.
The authors have organized the images so that they give just the flow
of information a student needs to build up a clear mental image of the
human body. Each two-page spread is a self-contained lesson that unobtrusively shows the hand of an experienced and thoughtful teacher.
I wish I could have held this book in my hands when I was a student;
I envy any student who does so now.
Robert D. Acland, 1941–2016
Louisville, Kentucky
December 2015
Preface
In this new fourth edition of the Atlas of Anatomy, we are proud to offer
what we believe is our best effort at presenting a clear and accurate story
of human anatomy. A significant part of this effort is the addition of our
newest co-author, Dr. Jamie C. Wikenheiser from the University of California, Irvine. Jamie’s love of anatomy, attention to detail, and proud
background in teaching excellence in anatomy at all student levels makes
him a highly qualified addition to the editorship of the Atlas that will
ensure its continued development.
As with previous editions, we have made every attempt to respond to
the requests, comments, and critiques of our world-wide users. As always, we recognize that anatomy is a changing science. As concepts and
terminology evolve, we feel a responsibility to pass this on and keep
these aspects of the Atlas updated. Thus, our initial task for this edition
was to update and further clarify the material already present in the
Atlas. Among these modifications was a major revision of the many autonomic innervation wiring schematics. These are now uniformly designed to clearly differentiate between sympathetic and parasympathetic
components and pre-and post-ganglionic fibers. We improved many
tables by reorganizing and rewording the content and enlarging labels.
Sectional and radiographic chapters in each unit, established in the third
edition, have been expanded with more than forty additional MR and CT
images, now accompanied, as are all sectional images throughout the
Atlas, by new simplified navigators.
Another focus of this edition was to provide more written and schematic-­
based information that addresses complex anatomic concepts. This includes new schematics that complement other images, expanded legends
that accompany images, and most notably, the addition of almost thirty
new clinical boxes (most with illustrations) in every unit. These focus on
function, pathology, anatomic variations, clinical procedures, diagnostic
techniques, embryological development, and aging.
We continue to try to make difficult areas of anatomy more easily understood through better organization of chapter content and new diagrammatic approaches. The two-page spread that has been so popular in
previous editions has been maintained in this edition, but an effort was
made to improve their layouts by tabulating some content and adding
more than 120 new illustrations and images. In this edition, the reader
will notice major changes in two regions. In the abdomen and pelvic
units, a greater focus is placed on the peritoneum, mesenteries, and
peritoneal spaces. The inguinal region, a difficult area for students, is
also expanded with new images and tables, as well as new and revised
images of perineal structures. The head and neck unit is the second area
of major revisions. In an effort to bring this material into alignment with
the way it is usually encountered in the dissection lab, the chapter on the
neck now precedes those on the head and includes new artwork that
promotes the dissection views. Students will appreciate the reorgani­
zation and additional clarifying images of areas such as the cavernous
sinus, pterygopalatine and infratemporal fossae, and oral and nasal cavities. Finally, a new expanded overview introduces the brain and nervous
system chapter.
As always, we are extremely grateful for the contributions of the many
colleagues and reviewers who provide important feedback on earlier
editions, alert us to inaccuracies and ambiguities, and share suggestions
for new material.
We recognize that our efforts, though important, are just one part of the
process that brings this textbook to its final production. The entire Thieme
Publishers team has encouraged and supported our efforts throughout
this process. Our deep appreciation is extended to the most important
contributors: Judith Tomat, Developmental Editor; Delia DeTurris, Acquisitions Editor, and Barbara Chernow, PhD, Production Manager, for their
dedication and expertise in their respective fields and their confidence in
our ability to produce a quality manuscript.
Anne M. Gilroy
Worcester, Massachusetts
Brian R. MacPherson
Lexington, Kentucky
Jamie C. Wikenheiser
Irvine, California
December 2019
Preface to the First Edition
Each of the authors was amazed and impressed with the extraordinary
detail, accuracy, and beauty of the illustrations that were created for
the Thieme Atlas of Anatomy. We feel these images are one of the most
significant additions to anatomical education in the past 50 years. It
was our intent to use these exceptional illustrations as the cornerstone
of our effort in creating a concise single volume Atlas of Anatomy for the
curious and eager health science student.
Our challenge was first to select from this extensive collection those
images that are most instructive and illustrative of current dissection approaches. Along the way, however, we realized that creating a
single-volume atlas was much more than choosing images: each image has to convey a significant amount of detail while the appeal and
labeling need to be clean and soothing to the eye. Therefore, hundreds
of illustrations were drawn new or modified to fit the approach of this
new atlas. In addition, key schematic diagrams and simplified summary-form tables were added wherever needed. Dozens of applicable
radiographic images and important clinical correlates have been added
where appropriate. Additionally, surface anatomy illustrations are
accompanied by questions designed to direct the student’s attention to anatomic ­detail that is most relevant in conducting the physical exam. Elements from each of these features are arranged in a
regional format to facilitate common dissection approaches. Within
each region, the various components are examined systemically,
followed by topographical images to tie the systems together within
the region. In all of this, a clinical perspective on the anatomical structures is taken. The unique two facing pages “spread” format focuses the
user to the area/topic being explored.
We hope these efforts — the results of close to 100 combined years
experience teaching the discipline of anatomy to bright, enthusiastic
students — has resulted in a comprehensive, easy-to-use resource and
reference.
We would like to thank our colleagues at Thieme Publishers who
so professionally facilitated this effort. We cannot thank enough­
Cathrin E. Schulz, MD, Editorial Director, Educational Products, who
so graciously reminded us of deadlines, while always being available to
“trouble shoot” problems. More importantly, she encouraged, helped,
and complimented our efforts.
We also wish to extend very special thanks and appreciation to Bridget
Queenan, Developmental Editor, who edited and developed the
manuscript with an outstanding talent for visualization and intuitive
flow of information. We are very grateful to her for catching many details along the way while always patiently responding to requests for
artwork and labeling changes.
Cordial thanks to Elsie Starbecker, Senior Production Editor, who with
great care and speed produced this atlas with its over 2,200 illustrations. Finally, thanks to Rebecca McTavish, Developmental Editor, for
joining the team in the correction phase. So very much of their hard
work has made the Atlas of Anatomy a reality.
Anne M. Gilroy
Worcester, Massachusetts
Brian R. MacPherson
Lexington, Kentucky
Lawrence M. Ross
Houston, Texas
March 2008
Back
1 Surface Anatomy
Surface Anatomy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
2 Bones, Ligaments & Joints
Vertebral Column: Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Vertebral Column: Elements . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Cervical Vertebrae . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Thoracic & Lumbar Vertebrae . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Sacrum & Coccyx . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Intervertebral Disks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Joints of the Vertebral Column: Overview . . . . . . . . . . . . . . . . 16
Joints of the Vertebral Column: Craniovertebral Region . . . . . 18
Vertebral Ligaments: Overview & Cervical Spine . . . . . . . . . . 20
Vertebral Ligaments: Thoracolumbar Spine . . . . . . . . . . . . . . 22
3 Muscles
Muscles of the Back: Overview . . . . . . . . . . . . . . . . . . . . . . . . .
Intrinsic Muscles of the Cervical Spine . . . . . . . . . . . . . . . . . . .
Intrinsic Muscles of the Back . . . . . . . . . . . . . . . . . . . . . . . . . .
Muscle Facts (I) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Muscle Facts (II) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Muscle Facts (III) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
24
26
28
30
32
34
4 Neurovasculature
Arteries & Veins of the Back . . . . . . . . . . . . . . . . . . . . . . . . . . .
Nerves of the Back . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Spinal Cord . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Spinal Cord Segments & Spinal Nerves . . . . . . . . . . . . . . . . . .
Arteries & Veins of the Spinal Cord . . . . . . . . . . . . . . . . . . . . .
Neurovascular Topography of the Back . . . . . . . . . . . . . . . . . .
36
38
40
42
44
46
5 Sectional & Radiographic Anatomy
Radiographic Anatomy of the Back (I) . . . . . . . . . . . . . . . . . . . 48
Radiographic Anatomy of the Back (II). . . . . . . . . . . . . . . . . . . 50
1
Surface Anatomy
Back
Surface Anatomy
Fig. 1.1 Palpable structures of the back
Posterior view.
Vertebra
prominens (C7)
Acromion
Greater
tubercle,
humerus
Scapular
spine
Medial
border,
scapula
Inferior
angle,
scapula
6th through
12th ribs
Iliac crest
Anterior
superior
iliac spine
Posterior
superior
iliac spine
Sacrum
Greater
trochanter,
femur
Ischial
tuberosity
Trapezius
Deltoid
A
Bony prominences.
Teres
major
Teres
minor
Triceps
brachii
Latissimus
dorsi
External
oblique
Gluteus
medius
Gluteus
maximus
B
Musculature.
2
Thoracolumbar
fascia
Fig. 1.2 Regions of the back and buttocks
Posterior view.
1 Surface Anatomy
Vertebral
region
Suprascapular
region
Deltoid region
Scapular region
Interscapular
region
Lateral
pectoral region
Fig. 1.3 Spinous processes and landmarks
of the back
Posterior view.
Infrascapular
region
C7 spinous process
(vertebra prominens)
Lumbar triangle
Cervicothoracic
junction
Sacral region
T3 spinous
process
Gluteal region
Anal region
Scapular spine
T7 spinous
process
Inferior angle
of scapula
T12 spinous
process
Paravertebral Scapular
line
line
12th rib
Posterior
midline
L4 spinous process
Iliac crest
Posterior superior
iliac spine
S2 spinous process
Table 1.2
Table 1.1
Posterior midline
Reference lines
of the back
Posterior trunk midline at
the level of the spinous
processes
Paravertebral line
Line at the level of the
transverse processes
Scapular line
Line through the inferior
angle of the scapula
Spinous processes that provide useful posterior landmarks
Vertebral spinous
process
Posterior landmark
C7
Vertebra prominens
(the projecting spinous process of C7 is clearly visible and palpable)
T3
The scapular spine
T7
The inferior angle of the scapula
T12
Just below the 12th rib
L4
The summit of the iliac crest
S2
The posterior superior iliac spine (recognized by small skin depressions
directly over the iliac spines)
3
2
Bones, Ligaments & Joints
Back
Vertebral Column: Overview
The vertebral column (spine) is divided into four regions: the cervical,
thoracic, lumbar, and sacral spines. Both the cervical and lumbar spines
demonstrate lordosis (inward curvature); the thoracic and sacral
spines demonstrate kyphosis (outward curvature).
Fig. 2.1 Vertebral column
Left lateral view.
Craniocervical junction
Cervical spine
C1–C7
vertebrae
Cervicothoracic junction
Spinous
process
Thoracic spine
Thoracolumbar junction
Lumbar spine
Lumbosacral junction
T1–T12
vertebrae
Costal
facets
Articular
processes
Sacrum (sacral spine)
A Regions of the spine.
Intervertebral foramina
Clinical box 2.1
L1–L5
vertebrae
Spinal development
The characteristic curvatures of the adult spine appear over the course
of postnatal development, being only partially present in a newborn. The
newborn has a “kyphotic” spinal curvature (A); lumbar lordosis develops
later and becomes stable at puberty (C).
Intervertebral disk
Adult spinal
column
Kyphotic
spine
of the
newborn
Transitional
phase
Sacral
promontory
Cervical
lordosis
Thoracic
kyphosis
Lumbar
lordosis
Sacral
kyphosis
A
4
B
C
Sacrum
(S1–S5
vertebrae)
Coccyx
B Bony vertebral column.
Fig. 2.2 Normal anatomical position of the spine
Left lateral view.
Larynx
Spinous process of
vertebra prominens (C7)
Trachea
Inflection points
Line of gravity
Spinal cord
Ascending
aorta
Heart
Esophagus
Diaphragm
Vertebral canal
Intervertebral disk
Spinous process
Liver
Body of L1
Conus medullaris
Stomach
Whole-body
center of gravity
2 Bones, Ligaments & Joints
Dens of axis (C2)
Dens of axis (C2)
Tongue
External
auditory canal
Abdominal
aorta
Cauda equina
Sacral promontory
A
Line of gravity. The line of gravity passes
through certain anatomical landmarks,
including the inflection points at the cervicothoracic and thoracolumbar junctions.
It continues through the center of gravity
(anterior to the sacral promontory) before
passing through the hip joint, knee, and
ankle.
Bladder
Coccyx
Rectum
B Midsagittal section through an adult male.
Clinical box 2.2
Abnormal Vertebral Column Curvatures
Scoliotic
curve
A Normal
BExcessive
kyphosis
C Excessive
lordosis
Asymmetrical
waistline
D Scoliosis
E
Right convex
thoracic scoliosis
5
Back
Vertebral Column: Elements
Fig. 2.3 Bones of the vertebral column
The transverse processes of the lumbar vertebrae are originally rib
rudiments and so are named costal processes.
Atlas (C1)
Axis (C2)
Atlas (C1)
Dens of axis (C2)
C1—C7
vertebrae
Transverse
processes
T1—T12
vertebrae
Vertebra
prominens
(C7)
Spinous
processes
Transverse
processes
Vertebral
body
Intervertebral
disk
L1
Costal
processes
L1—L5
vertebrae
Sacrum
(fused
S1—S5
vertebrae)
Coccyx
(Co1—Co4
vertebrae)
A Anterior view.
6
Sacrum
Anterior
sacral
foramina
Coccyx
B Posterior view.
Posterior
sacral
foramina
Fig. 2.4 Structural elements of a vertebra
Fig. 2.5 Typical vertebrae
Superior
articular
process
Vertebral
body
Vertebral
arch
Superior view.
Vertebral
foramen
Lamina
Vertebral arch
Transverse
process
Pedicle
Lamina
Spinous process
Superior articular facet
Pedicle
Posterior tubercle
Transverse process with
groove for spinal n.
Spinous
process
Transverse foramen
Body
Inferior
articular process
Anterior
tubercle
A Cervical vertebra (C4).
2 Bones, Ligaments & Joints
Left posterosuperior view. With the exception of the atlas (C1)
and axis (C2), all vertebrae consist of the same structural
elements.
Spinous process
Costal facet
Lamina
Transverse process
Pedicle
Superior articular facet
Inferior costal facet
Superior costal facet
Body
Median
sacral crest
B Thoracic vertebra (T6).
Spinous process
Accessory process
Sacral canal
Superior articular process
Superior
articular
facet
Transverse process
Vertebral arch
Lateral part
of sacrum
Superior articular process
Vertebral foramen
Superior vertebral
notch
Body
Base of Promontory
sacrum
C Lumbar vertebra (L4).
Table 2.1
Wing of
sacrum
D Sacrum.
Structural elements of vertebrae
Vertebrae
Body
Cervical vertebrae
C3*–C7
Small
(kidney-shaped)
Thoracic vertebrae
T1–T12
Medium (heartshaped); includes
costal facets
Vertebral foramen
Transverse processes
Articular processes
Spinous process
Large (triangular)
Small (may be absent
on C7); anterior and
posterior tubercles
enclose transverse
foramen
Superoposteriorly and
inferoanteriorly; oblique facets:
most nearly horizontal
Short (C3–C5); bifid (C3–C6);
long (C7)
Small (circular)
Large and strong; length
decreases T1–T12; costal
facets (T1–T10)
Posteriorly (slightly laterally)
and anteriorly (slightly
medially); facets in coronal
plane
Long, sloping posteroinferiorly; tip extends to level
of vertebral body below
Posteromedially (or medially)
and anterolaterally (or laterally);
facets nearly in sagittal
plane; mammillary process
on posterior surface of each
superior articular process
Short and broad
Superoposteriorly (SI) superior
surface of lateral sacrumauricular surface
Median sacral crest
Lumbar vertebrae
L1–L5
Large
(kidney-shaped)
Medium (triangular)
Called costal processes,
long and slender;
accessory process on
posterior surface
Sacral vertebrae (sacrum)
S1–S5 (fused)
Decreases from
base to apex
Sacral canal
Fused to rudimentary rib
(ribs, see pp. 56–59)
*C1 (atlas) and C2 (axis) are considered atypical (see pp. 8–9).
7
Back
Cervical Vertebrae
The seven vertebrae of the cervical spine differ most conspicuously
from the common vertebral morphology. They are specialized to bear
the weight of the head and allow the neck to move in all directions.
C1 and C2 are known as the atlas and axis, respectively. C7 is called the
vertebra prominens for its long, palpable spinous ­process.
Fig. 2.6 Cervical spine
Left lateral view.
Posterior
arch of atlas
Anterior
tubercle
Posterior
tubercle
C1 (atlas)
C2 (axis)
Spinous
process
Groove for
spinal n.
Vertebral
body
Zygapophyseal joint
Anterior
tubercle
Fig. 2.7 Atlas (C1)
Posterior
tubercle
Anterior
tubercle
Transverse
foramen
Inferior articular
process
Posterior
tubercle
Superior articular
process
Groove for
spinal n.
Uncovertebral
joint
Groove for
vertebral a.
Superior
articular facet
Posterior
arch of atlas
Transverse
process
Inferior
articular facet
A Left lateral view.
Fig. 2.8 Axis (C2)
Spinous
process
Uncinate process
Anterior
articular facet
Superior
articular facet
C7 (vertebra
prominens)
Transverse
process
Dens
Posterior
articular facet
Spinous
process
Transverse
foramen
Transverse foramen
Body
A Bones of the cervical spine, left lateral view.
Transverse
process
Inferior
articular facet
Vertebral
arch
A Left lateral view.
C1 (atlas)
Fig. 2.9 Typical cervical vertebra (C4)
C2 (axis)
Transverse
foramen
Superior
articular process
Transverse process
Superior articular facet
Body
Inferior articular
process
C7 spinous
process
Groove for
spinal n.
B
Radiograph of the cervical spine, left lateral view.
8
A Left lateral view.
Inferior
articular facet
Spinous
process
Clinical box 2.3
The cervical spine is prone to hyperextension
injuries, such as “whiplash,” which can occur
when the head extends back much farther than
it normally would. The most common injuries
of the cervical spine are fractures of the dens of
the axis, traumatic spondylolisthesis (anterior
slippage of a vertebral body), and atlas fractures.
Patient prognosis is largely dependent on the
spinal level of the injuries (see p. 42).
Superior
articular facet
Spinous process
of C1
Anterior displacement of body of
C2 vertebra
Spinous process
of C2
Fractured
vertebral
arch of C2
Vertebral
body of C3
Anterior
arch
Posterior tubercle
Posterior arch
Superior
articular
facet
This patient hit the dashboard of his
car while not wearing a seat belt.
The resulting hyperextension caused
the traumatic spondylolisthesis of C2
(axis) with fracture of the vertebral
arch of C2, as well as tearing of
the ligaments between C2 and C3.
This injury is often referred to as
“hangman’s fracture.”
2 Bones, Ligaments & Joints
Injuries in the cervical spine
Groove for
vertebral a.
Lateral
masses
Transverse process
Transverse foramen
Transverse
foramen
Inferior
articular
facet
Anterior
tubercle
Transverse
process
B Anterior view.
Anterior arch
Anterior
tubercle
C Superior view.
Spinous process
Anterior
articular facet
Dens
Vertebral
foramen
Superior
articular facet
Vertebral arch
Inferior
articular
process
Dens
Transverse
process
Body
Transverse
process
Superior
articular
facet
Inferior
articular facet
B Anterior view.
Transverse
foramen
Anterior articular facet
C Superior view.
Uncinate
process
Superior
articular
process
Posterior
tubercle
Groove for
spinal n.
Anterior
tubercle
Body
Spinous
process
B Anterior view.
Facet for dens
Inferior
articular
facet
Vertebral foramen
Spinous process
Vertebral arch
Lamina
Transverse
process
Superior
articular facet
Pedicle
Transverse
process with
groove for
spinal n.
Posterior tubercle
Body
Transverse
foramen
Anterior
tubercle
C Superior view.
9
Back
Thoracic & Lumbar Vertebrae
Fig. 2.10 Thoracic spine
Left lateral view.
Fig. 2.11 Typical thoracic vertebra (T6)
Spinous process
Superior
vertebral notch
1st thoracic
vertebra (T1)
Superior
costal facet
Inferior articular
process
Superior articular
process
Superior
articular facet
Transverse
process
Costal facet on
transverse
process
Body
Inferior
vertebral notch
Transverse
process
Inferior
costal facet
Superior
costal facet
Inferior
costal facet
Costal facet
on transverse
process
Zygapophyseal joint
Inferior
articular facet
Spinous
process
A Left lateral view.
Superior
articular process
Transverse
process
Body
Vertebral
body
Superior
costal facet
Intervertebral
foramen
Inferior
vertebral
notch
Superior
vertebral
notch
12th thoracic
vertebra (T12)
Inferior
costal facet
Costal facet
on transverse
process
Spinous process
Inferior
articular facet
B Anterior view.
Costal facet on
transverse process
Spinous process
Lamina
Inferior
articular facet
Transverse
process
Pedicle
Inferior
costal facet
Superior
vertebral notch
Superior
costal facet
Body
C Superior view.
10
Superior
articular facet
Fig. 2.12 Lumbar spine
Left lateral view.
Superior articular
process
Superior
articular process
Transverse process
Mammillary process
Intervertebral
foramen
Inferior
vertebral
notch
Transverse
process
Body
Spinous
process
Spinous
process
Superior
vertebral
notch
Inferior
vertebral notch
Zygapophyseal
joint
Inferior
articular process
Vertebral
body
5th lumbar
vertebra (L5)
Inferior
articular facet
2 Bones, Ligaments & Joints
1st lumbar
vertebra (L1)
Fig. 2.13 Typical lumbar vertebra (L4)
A Left lateral view.
Inferior
articular facet
Inferior
articular process
Body
Superior
articular
process
Transverse
process
Clinical box 2.4
Osteoporosis
The spine is the structure most affected by degenerative diseases of the
skeleton, such as arthrosis and osteoporosis. In osteoporosis, more bone
material gets reabsorbed than built up, resulting in a loss of bone mass.
Symptoms include compression fractures and resulting back pain.
Inferior
articular facet
Inferior
articular process
Spinous
process
B Anterior view.
Spinous process
Accessory
process
Vertebral
arch
Vertebral
foramen
Body
A
Radiograph of a normal
lumbar spine, left lateral
view. (Reproduced from
Moeller TB, Reif E. Pocket
Atlas of Radiographic
Anatomy, 3rd ed. New
York, NY: Thieme; 2010.)
B
Radiograph of an osteoporotic lumbar
spine with a compression fracture at
L1 (arrow). Note that the vertebral
bodies are decreased in density, and
the internal trabecular structure is
coarse. (Reproduced from Jallo J,
Vaccaro AR. Neurotrauma and Critical
Care of the Spine, 1st ed. New York,
NY: Thieme; 2009.)
Superior
articular facet
Mammillary
process
Transverse process
Superior articular process
Superior
vertebral
notch
C Superior view.
11
Back
Sacrum & Coccyx
The sacrum is formed from five postnatally fused sacral vertebrae.
The base of the sacrum articulates with the 5th lumbar vertebra, and
the apex articulates with the coccyx, a series of three or four rudimentary vertebrae. See Fig. 19.1, p. 230.
Fig. 2.14 Sacrum and coccyx
Promontory
Superior
articular
process
Wing of
sacrum
Lateral
part
Transverse
lines
Anterior sacral
foramina
Apex of
sacrum
Superior
articular
facet
Sacrococcygeal
joint
Sacral
tuberosity
Sacral
canal
Coccyx
A Anterior view.
Lateral
part
Auricular
surface
Lateral
sacral crest
Median
sacral crest
Posterior sacral
foramina
Medial sacral crest
Sacral hiatus
Coccygeal cornu
Coccyx
B Posterior view.
12
Sacral cornua
Sacrococcygeal
joint
Superior
articular process
Sacral
promontory
Sacral
promontory
Auricular
surface
Sacral
tuberosity
Sacroiliac
joint
2 Bones, Ligaments & Joints
Base of
sacrum
Posterior
surface
Anterior (pelvic) surface
Lateral
sacral crest
DRadiograph of sacrum, anteroposterior view. (Reproduced from
Moeller TB, Reif E. Pocket Atlas of Radiographic Anatomy, 3rd ed.
New York, NY: Thieme; 2010.)
Coccyx
C Left lateral view.
Fig. 2.15 Sacrum
Superior view.
Median
sacral crest
Median
Superior
sacral crest
articular process
Sacral
canal
Lateral
part of
sacrum
Sacral
canal
Posterior
sacral
foramen
Lateral
part
Promontory
Wing of
sacrum
Pelvic
surface
Anterior
sacral foramen
Coccyx
A Base of sacrum, superior view.
Transverse section through second sacral vertebra demonstrating
B
anterior and posterior sacral foramina, superior view.
13
Back
Intervertebral Disks
Fig. 2.16 Intervertebral disk
in the vertebral column
Vertebral canal
Midsagittal section of T11–T12, left lateral
view. The intervertebral disks occupy the
spaces between vertebrae (intervertebral
joints, see p. 16).
Vertebral body
Intervertebral
disk
Superior
articular
facet
Anulus
fibrosus
Vertebral
arch
Nucleus
pulposus
Spinous process
Ligamentum
flavum
Interspinous
lig.
Anulus
fibrosus
Fig. 2.17 Structure of
intervertebral disk
Nucleus
pulposus
Superior
articular process
Transverse
process
Anterosuperior view with the anterior half of
the disk and the right half of the end plate
removed. The intervertebral disk consists of
an external fibrous ring (anulus fibrosus) and
a gelatinous core (nucleus pulposus).
Hyaline
cartilage
end plate
Intervertebral
surface
Fig. 2.18 Relation of intervertebral
disk to vertebral canal
Body
Marginal ridge
(epiphyseal ring)
Fig. 2.19 Outer zone of the annulus fibrosus
Anterior view of L3–L4 with intervertebral disk.
Fourth lumbar vertebra, superior view.
Marginal ridge
(epiphyseal ring)
Spinous process
Vertebral
foramen
Superior
vertebral
notch
Superior
articular process
Superior articular
process
Transverse
process
Transverse
process
Intervertebral
foramen
Vertebral
bodies
Crossing fiber
systems of the
anulus fibrosus
Nucleus pulposus
Anulus
fibrosus
Inner zone
Outer zone
Inferior
articular
process
14
Spinous process
Clinical box 2.5
As the stress resistance of the anulus fibrosus declines with age, the tissue of
the nucleus pulposus may protrude through weak spots under loading. If the
fibrous ring of the anulus ruptures completely, the herniated material may
compress the contents of the intervertebral foramen (nerve roots and blood
vessels—see posterolateral herniation below). These patients often suffer
from severe local back pain. Pain is also felt in the associated dermatome
(see p. 42). When the motor part of the spinal nerve is affected, the muscles
served by that spinal nerve will show weakening. It is an important diagnostic
step to test the muscles innervated by a nerve from a certain spinal segment,
as well as the sensitivity in the specific dermatome. Example: The first sacral
nerve root innervates the gastrocnemius and soleus muscles; thus, standing
or walking on toes can be affected (see p. 446).
Cauda
equina
Epidural
fat
Fat in the
epidural
space
L3
Intervertebral
foramen
Dural sleeve
with spinal n.
Herniated
disk
Cauda
equina in
CSF*-filled
dural sac
L4
Central
herniation
Sacrum
Nucleus
pulposus
A Superior view.
B Midsagittal T2-weighted MRI (magnetic
resonance image).
Posterior herniation (A, B) In the MRI, a conspicuously herniated disk at the
level of L3–L4 protrudes posteriorly (transligamentous herniation). The dural
sac is deeply indented at that level. *CSF (cerebrospinal fluid).
Spinal
dura mater
Dural sac
Spondylophyte
Dural sleeve
with spinal n.
Compressed
nerve roots
Posterolateral
herniation
Posterolateral
herniation
Nucleus
pulposus
Intervertebral disk
Pedicle
(cut surface)
Dural sleeve with spinal n.
C Superior view.
Posterolateral herniation (C, D) A posterolateral herniation may compress
the spinal nerve as it passes through the intervertebral foramen. If more
Bone
drill
2 Bones, Ligaments & Joints
Disk herniation in the lumbar spine
D Posterior view, vertebral arches removed.
medially positioned, the herniation may spare the nerve at that level but
impact nerves at inferior levels.
Microsurgical
instrument
L3
Herniated
disc
L4
L5
S1
E
Microdiscectomy surgery (E, F) is performed in order to remove a portion
of a ­herniated disc that is irritating the nerve root. Through a small incision,
the erector spinae muscles are reflected laterally to expose the ligamentum flavum, which is then removed in order to access the nerve roots in
F
Compressed
nerve
the ­spinal canal. A small portion of the facet joint may be ­removed to both
facilitate access and relieve pressure on the nerve roots. Only the herniated
portion of the disk is removed with the remaining tissue left intact.
15
Back
Joints of the Vertebral Column: Overview
Table 2.2
Joints of the vertebral column
①
Craniovertebral joints
①
Atlanto-occipital joints
Occiput–C1
②
Atlantoaxial joints
C1–C2
Joints of the vertebral bodies
②
③
Uncovertebral joints
C3–C7
④
Intervertebral joints
C2–S1
Joints of the vertebral arch
⑤
Zygapophyseal joints
C2–S1
③
Fig. 2.20 Zygapophyseal (intervertebral facet) joints
The orientation of the zygapophyseal joints differs between the spinal
regions, influencing the degree and direction of movement.
⑤
Transverse
process
Superior articular
process
Anterior
tubercle
Spinous process
Posterior
tubercle
Zygapophyseal
joint
Groove for
spinal n.
④
Transverse
foramen
Inferior articular
process
A
Cervical region, left lateral view. The zygapophyseal joints lie
45 degrees from the horizontal.
Superior
articular facet
Vertebral foramen
Costal facet
Superior
articular process
Transverse
process
Zygapophyseal joint
Zygapophyseal
joint
Transverse
process
Inferior articular
facet
B
Thoracic region, left lateral view. The joints lie in the coronal plane.
16
Spinous process
Inferior
articular process
C Lumbar region, posterior view. The joints lie in the sagittal plane.
Fig. 2.21 Uncovertebral joints
Dens
Lateral
atlantoaxial
joint
Atlas (C1)
Clinical box 2.6
Proximity of the spinal nerve and vertebral artery
to the uncinate process
The spinal nerve and vertebral artery pass through the intervertebral
and transverse foramina, respectively (A and B). Bony outgrowths
(osteophytes) on the uncinate process (C) resulting from uncovertebral
arthrosis (degeneration) may compress both the nerve and the artery and
can lead to chronic pain in the cervical region.
Vertebral a.
in transverse
foramen
Axis (C2)
C1 spinal n.
Atlas (C1)
Axis (C2)
Uncinate
processes
Vertebral a.
Vertebral body
Transverse
process
Posterior
tubercle
Anterior
tubercle
2 Bones, Ligaments & Joints
Anterior view. Uncovertebral joints form during childhood between
the uncinate processes of C3–C7 and the vertebral bodies immediately
superior. The joints may result from fissures in the cartilage of the disks
that assume an articular character. If the fissures become complete
tears, the risk of nucleus pulposus herniation is increased (see p. 15).
Uncinate
processes
Intervertebral
disk
Groove for
spinal n.
Transverse
process
Spinal n.
in groove
C7 spinal n.
Vertebral body (C7)
Inferior
articular facet
A Cervical spine, anterior view.
Spinous
process
A
Uncovertebral joints in the cervical spine of an 18-year-old man,
anterior view.
Vertebral
foramen
Lamina
Spinal
cord
Anulus
fibrosus
Superior
articular facet
Spinal n.
Posterior root
(spinal) ganglion
Nucleus
pulposus
Transverse
Vertebral
process
body
Transverse
Uncinate
foramen
process
Vertebral a.
B
Uncovertebral joint (enlarged), anterior view of coronal section.
B Fourth cervical vertebra, superior view.
Spinous process
Spondylophytes
Inferior
articular process
Uncovertebral
joint
Superior
articular
facet
Transverse
foramen
Vertebral
body
C
Uncovertebral joints, split intervertebral disks,
anterior view of coronal section.
Uncinate
process
Advanced uncovertebral arthrosis of the
C
fourth cervical vertebra, superior view.
17
Back
Joints of the Vertebral Column: Craniovertebral Region
Fig. 2.22 Craniovertebral joints
Superior
nuchal line
External occipital
protuberance
Occipital condyle
Mastoid process
(temporal bone)
Dens of axis (C2)
Atlas (C1)
Styloid process
(temporal bone)
Median
atlantoaxial joint
Axis (C2)
Superior articular
facet (lateral mass
of atlas)
Dens of
axis (C2)
A Posterior view.
Groove for
vertebral a.
Transverse
process
Fig. 2.23 Ligaments of the
craniovertebral joints
Spinous process
Median
atlantoaxial
joint
Anterior
tubercle
Superior
articular facet
B Atlas and axis, posterosuperior view.
Alar ligs.
Apical lig.
of the dens
Transverse lig.
of atlas
Transverse
process
Dens
Lateral mass
of the atlas
Vertebral foramen
Longitudinal fascicles
Posterior tubercle
of the atlas
A
Ligaments of the median atlantoaxial joint,
superior view. The fovea of the atlas is hidden by the joint capsule.
Spinous process
of axis
Alar ligs.
Longitudinal
fascicles
Apical lig.
of the dens
Superior
articular
facet
Tectorial membrane
Transverse lig.
of atlas
Capsule of
lateral atlantooccipital joint
Transverse process
Intertransverse lig.
Groove for
vertebral a.
Posterior
atlanto-occipital
membrane
Posterior arch
of atlas
Nuchal lig.
Spinous process
B
Ligaments of the craniovertebral joints, posterosuperior view.
The dens of the axis is hidden by the tectorial membrane.
18
the two lateral and one medial articulations between the atlas (C1) and
axis (C2).
Fig. 2.24 Dissection of the craniovertebral joint ligaments
External occipital
protuberance
Nuchal
lig.
2 Bones, Ligaments & Joints
The atlanto-occipital joints are the two articulations between the
convex occipital condyles of the occipital bone and the slightly concave
superior articular facets of the atlas (C1). The atlantoaxial joints are
Styloid process
Posterior atlantooccipital membrane
Atlas
(C1)
Lateral atlantoaxial
joint (capsule)
Nuchal lig.
Axis
(C2)
Ligamentum
flavum
Atlanto-occipital
joint
A
Nuchal ligament and posterior atlantooccipital membrane.
Posterior
atlantooccipital
membrane
Posterior arch
of atlas
Tectorial membrane
(posterior
longitudinal lig.)
Spinous process
Vertebral arch
Alar ligs.
B
Posterior longitudinal ligament. Removed:
Spinal cord; vertebral canal windowed.
Atlantooccipital
capsule
Longitudinal
fascicles*
Apical lig.
of dens
Transverse
lig. of atlas*
Posterior longitudinal lig.
C
Cruciform ligament of atlas (*). Removed:
Tectorial membrane, posterior atlantooccipital membrane, and vertebral arches.
Alar lig.
Lateral
mass
of C1
Dens, posterior
articular surface
DAlar and apical ligaments. Removed:
Transverse ligament of atlas.
19
Back
Vertebral Ligaments: Overview & Cervical Spine
The ligaments of the spinal column bind the vertebrae and enable the
spine to withstand high mechanical loads and shearing stresses and
limit the range of motion. The ligaments are subdivided into vertebral
body ligaments and vertebral arch ligaments.
Fig. 2.25 Vertebral ligaments
Viewed obliquely from the left posterior view.
A
Anterior
longitudinal lig.
Table 2.3
Transverse
process
Vertebral ligaments
Ligament
Location
Vertebral body ligaments
P Posterior longitudinal
lig.
Inter- ④
transverse
lig.
Pedicle
Vertebral
arch
Lamina
Inferior articular
process
Supraspinous
lig.
Superior articular
process
①
Ligamentum flavum
Interspinous lig.
③
Spinous
process
②
A
Anterior longitudinal lig.
Along anterior surface of
vertebral body
P
Posterior longitudinal lig.
Along posterior surface of
vertebral body
Vertebral arch ligaments
①
Ligamentum flavum
Between laminae
②
Interspinous lig.
Between spinous process
③
Supraspinous lig.
Along posterior ridge of
spinous processes
④
Intertransverse lig.
Between transverse processes
Nuchal lig.*
Between external occipital
protuberance and spinous
process of C7
*Corresponds to a supraspinous ligament that is broadened superiorly.
Fig. 2.26 Anterior longitudinal ligament
Fig. 2.27 Posterior longitudinal ligament
Anterior view with base of skull removed.
Internal
occipital
protuberance
Atlanto-occipital
joint (atlantooccipital capsule)
Atlas (C1)
Transverse
foramina
Axis (C2)
Anterior
longitudinal
lig.
Groove for
spinal nerve
Intervertebral
disk
20
Posterior view with vertebral canal opened via laminectomy and spinal
cord removed. The tectorial membrane is a broadened expansion of the
posterior longitudinal ligament.
External occipital
protuberance
Occipital
bone,
basilar
part
Anterior
atlantooccipital
membrane
Transverse
process
Lateral
atlantoaxial
joint (capsule)
Zygapophyseal
joint (capsule)
Posterior
tubercle
Atlanto-occipital
capsule
Posterior atlantooccipital membrane
Atlanto-occipital
joint
Tectorial membrane
Vertebral arch
Anterior
tubercle
Vertebra
prominens
(C7)
Posterior longitudinal
lig.
Fig. 2.28 Ligaments of the
cervical spine
Sella
turcica
Apical lig.
of the dens
Hypoglossal
canal
Tectorial
membrane
Mid-sagittal view.
Occipital bone,
basilar part
External
occipital
protuberance
Anterior
atlanto-occipital
membrane
Anterior arch
of atlas (C1)
Maxilla
Dens of axis (C2)
Longitudinal
fascicles
Posterior arch of atlas,
posterior tubercle
Zygapophyseal
joint capsule
Intervertebral disk
Anterior longitudinal
lig.
Posterior longitudinal
lig.
Transverse
lig. of atlas
Posterior
atlanto-occipital
membrane
2 Bones, Ligaments & Joints
Sphenoid sinus
Nuchal lig.
Ligamenta flava
Vertebral arch
Intervertebral foramen
Spinous process
Interspinous lig.
Supraspinous
lig.
C7 vertebral body
(vertebra prominens)
A
Midsagittal section, left lateral view. The nuchal ligament is the
broadened, sagittally oriented part of the supraspinous ligament that
extends from the vertebra prominens (C7) to the external occipital
protuberance.
Apex of dens
Body of axis
Cerebellomedullary
cistern
Posterior tubercle
of atlas
Nuchal lig.
Posterior longitudinal lig.
Vertebral body
Intervertebral
disk
Supraspinous lig.
Vertebra
prominens (C7)
Anterior
longitudinal
lig.
Spinal cord
Subarachnoid space
B
Midsagittal T2-weighted MRI, left lateral view.
21
Back
Vertebral Ligaments: Thoracolumbar Spine
Fig. 2.29 Ligaments of the vertebral
column: Thoracolumbar junction
Vertebral canal
Left lateral view of T11–L3, with T11–T12
sectioned in the midsagittal plane.
Intervertebral
disk
Superior articular
facet
Posterior longitudinal
lig.
Anulus
fibrosus
Vertebral arch
Nucleus
pulposus
Ligamenta flava
Superior articular
process
Anterior
longitudinal
lig.
Spinous processes
Interspinous ligs.
Transverse process
Vertebral body
Intertransverse ligs.
Zygapophyseal
joint capsule
Supraspinous
lig.
Inferior articular
facet
Clinical box 2.7
Spinal fusion procedure
Spinal fusion is a surgical procedure used
to restore stability to the vertebral column
or to eliminate painful motion. The basic
idea involves fusing two or more vertebrae
so they will heal into a single, solid bone.
Fusions can take place at any part of the
vertebral column.
A Midline cutaway
22
B Posterior view
Fig. 2.30 Anterior longitudinal ligament
Anterior view of L3–L5.
2 Bones, Ligaments & Joints
Transverse
process
Intervertebral
disk
Vertebral body
Fig. 2.31 Ligamenta flava and intertransverse
ligaments
Anterior view of opened vertebral canal at level of L2–L5.
Removed: L2–L4 vertebral bodies.
Superior
articular
process
Lamina
Anterior longitudinal lig.
Fig. 2.32 Posterior longitudinal ligament
Intertransverse
ligs.
Posterior view of opened vertebral canal at level of L2–L5.
Removed: L2–L4 vertebral arches at pedicular level.
Ligamenta
flava
Transverse
process
Nutrient
foramina
Pedicles (cut) of
vertebral arches
Posterior
longitudinal
lig.
Posterior
longitudinal
lig.
Superior
articular
process
Anterior
longitudinal
lig.
Inferior articular
facet
Intervertebral
foramen
Intervertebral
disk
Vertebral
body
Gap in
ligamentous
reinforcement
of the disk
Spinous process
Superior
articular facet
Transverse
process
Inferior articular
process
Spinous process
Vertebral canal
23
3
Muscles
Back
Muscles of the Back: Overview
The muscles of the back are divided into two groups, the ex­trinsic
and the intrinsic muscles, which are separated by the p
­ osterior layer
of the thoracolumbar fascia. The superficial extrinsic muscles are
considered muscles of the upper limb that have migrated to the back;
these muscles are discussed in the Upper Limb, pp. 312–317.
Fig. 3.1 Superficial extrinsic muscles of the back
Posterior view. Removed: Trapezius and latissimus dorsi (right). Revealed:
Thoracolumbar fascia. Note: The posterior layer of the thoracolumbar
fascia is reinforced by the aponeurotic origin of the latissimus dorsi.
Sternocleidomastoid
Thoracolumbar fascia
(= deep layer of nuchal fascia)
Trapezius
(descending part)
Trapezius
(transverse part)
Rhomboid minor
Levator
scapulae
Clavicle
Acromion
Scapular spine
Supraspinatus
Rhomboid
major
Deltoid
Infraspinatus
Scapula, medial border
Teres major
Teres major
Trapezius
(ascending part)
Serratus anterior
Triceps brachii
Latissimus dorsi (cut)
Latissimus dorsi
Serratus
posterior inferior
Thoracolumbar
fascia, posterior
layer
External
oblique
Olecranon
Aponeurotic
origin of
latissimus
dorsi
Internal
oblique
Lumbar
triangle,
internal
oblique
Iliac crest
Gluteal
aponeurosis
24
Gluteus
maximus
Fig. 3.2 Thoracolumbar fascia
Infrahyoid
muscles
Trachea
3 Muscles
and middle layer that unite at the lateral margin of the intrinsic back
muscles. In the neck, the posterior layer blends with the nuchal fascia
(deep layer), becoming continuous with the deep cervical fascia (prevertebral layer).
Transverse section, superior view. The intrinsic back muscles are
sequestered in an osseofibrous canal, formed by the thoracolumbar
fascia, the vertebral arches, and the spinous and transverse processes of
associated vertebrae. The thoracolumbar fascia consists of a posterior
Pretracheal
Esophagus visceral layer
A
Thyroid gland
Sternocleidomastoid
Pretracheal
muscular layer
Investing
(superficial) layer
Internal
jugular v.
Carotid sheath
Deep
cervical
fascia
B
Prevertebral layer
Vagus n.
Common
carotid a.
Longus colli
Scalene muscles
Brachial plexus
C6 vertebra
Spinal cord
Levator
scapulae
Intrinsic back
muscles
Trapezius
Deep layer
Superficial
layer
Nuchal fascia
A
Transverse section at level of C6 vertebra, superior view.
Psoas fascia
Abdominal
aorta
Inferior
vena cava
Parietal
peritoneum
Kidney
Renal fascia,
anterior layer
Lateral
abdominal
wall muscles
Transversalis fascia
L2 vertebra
Fibrous capsule
Psoas major
Renal fascia,
posterior layer
Latissimus dorsi
Vertebral arch
Serratus
posterior inferior
Transverse process of L2
Quadratus
lumborum
Spinous process of L1
Intrinsic
back muscles
Middle layer
Posterior
layer
Anterior layer
(quadratus
lumborum fascia)
Thoracolumbar
fascia
B Transverse section at level of L2, superior view.
Removed: Cauda equina and anterior trunk wall.
25
Back
Intrinsic Muscles of the Cervical Spine
Fig. 3.3 Muscles in the nuchal region
Posterior view. Removed: Trapezius, sternocleidomastoid, splenius, and
semispinalis muscles (right). Revealed: Nuchal muscles (right).
Parietal bone
Occipital bone
External occipital
protuberance
Semispinalis
capitis
Sternocleidomastoid
Superior
nuchal line
Splenius capitis
Semispinalis
capitis
Sternocleidomastoid
Mastoid process
Obliquus capitis
superior
Atlas (C1), transverse process
Rectus capitis
posterior minor
Rectus capitis
posterior major
Obliquus capitis
inferior
Longissimus capitis
Splenius capitis
Axis (C2), spinous process
26
Semispinalis capitis
Semispinalis
cervicis
Splenius capitis
Trapezius
Splenius cervicis
Fig. 3.4 Short nuchal muscles
Posterior view. See Fig. 3.6. Three of the short nuchal muscles
(obliquus capitis inferior, obliquus capitis superior and the rectus
capitis posterior major) form the boundaries of the suboccipital triangle
(region).
Rectus capitis
posterior minor
3 Muscles
Trapezius
Superior nuchal line
External occipital
protuberance
Inferior
nuchal line
Rectus capitis
posterior major
Semispinalis
capitis
Sternocleidomastoid
Obliquus
capitis superior
Splenius capitis
Obliquus
capitis superior
Mastoid process
Longissimus
capitis
Posterior atlanto-occipital
membrane (pierced by
vertebral a.)
Transverse
process of atlas (C1)
Rectus capitis
posterior major
Posterior arch
of atlas (C1)
Obliquus
capitis inferior
Spinous process
of axis (C2)
Interspinales
cervicis
Intertransversarii
cervicis
Transverse
process of C7
Spinous
process of C7
A Course of the short nuchal muscles.
Semispinalis
capitis
Rectus capitis
posterior minor
Rectus capitis
posterior major
Trapezius
Sternocleidomastoid
Splenius
capitis
Obliquus
capitis superior
Longissimus
capitis
Obliquus
capitis inferior
Intertransversarii
cervicis
Interspinales
cervicis
B Suboccipital region. Muscle origins are shown in red, insertions in blue.
27
Back
Intrinsic Muscles of the Back
The extrinsic muscles of the back (trapezius, latissimus dorsi, levator scapulae, and rhomboids) are discussed in the Upper Limb,
pp. 312–313. The serratus posterior, considered an intermediate
extrinsic back muscle, has been included with the superficial intrinsic
muscles in this unit.
Fig. 3.5 Intrinsic muscles of the back
Posterior view. Sequential dissection of the thoracolumbar fascia,
superficial intrinsic muscles, intermediate intrinsic muscles, and deep
intrinsic muscles of the back.
Thoracolumbar fascia
(= deep layer of
nuchal fascia)
Rhomboids
major and minor
(cut)
Serratus
posterior
superior
Semispinalis
capitis
Splenius
capitis
External
intercostal
muscles
Trapezius
(cut)
Thoracolumbar
fascia,
posterior
layer
Splenius
cervicis
Thoracolumbar
fascia (= deep layer
of nuchal fascia)
Serratus
posterior
inferior
Internal
oblique
Latissimus
dorsi (cut)
aponeurosis
External
oblique
(cut)
External
oblique
Iliac crest
External
intercostal
muscles
Spinalis
Iliocostalis
Longissimus
External
oblique
Gluteus
maximus
Internal
oblique
Iliac crest
A
Thoracolumbar fascia. Removed: Shoulder girdles and extrinsic back
muscles (except serratus posterior and aponeurotic origin of latissimus dorsi). Revealed: Posterior layer of thoracolumbar fascia.
Thoracolumbar fascia,
posterior layer
B
Superficial and intermediate intrinsic back muscles. Removed: Thoracolumbar fascia, posterior layer (left). Revealed: Erector spinae and
splenius muscles.
28
Splenius capitis
(cut)
Longissimus
capitis
Splenius
capitis
Iliocostalis
cervicis
Splenius
cervicis
Iliocostalis
thoracis
3 Muscles
Semispinalis
capitis
External
intercostal
muscles
Levatores
costarum
Spinalis
Longissimus
thoracis
Semispinalis
capitis
Superior
nuchal line
Splenius capitis
Rectus capitis
posterior minor
Obliquus
capitis superior
Iliocostalis
lumborum
Internal
oblique
Transversus
abdominis
Obliquus
capitis inferior
Rectus capitis
posterior major
Longissimus
capitis
Interspinales
cervicis
Spinalis
cervicis
Iliac crest
Rotatores
thoracis longi
Levatores
costarum
longi
Gluteus
maximus
Multifidus
Thoracolumbar
fascia, posterior layer
C
Intermediate and deep intrinsic back muscles. Removed: Longissimus
thoracis and cervicis, splenius muscles (left); iliocostalis (right).
Note: The posterior layer of the thoracolumbar fascia gives origin
to the internal oblique and transversus abdominis. Revealed: Deep
muscles of the back.
Rotatores
thoracis breves
External
intercostal
muscles
Spinalis
thoracis
Levatores
costarum
breves
Medial intertransversarii
lumbora
12th rib
Interspinales
lumborum
Lateral intertransversarii
lumbora
Transversus
abdominis
Costal
processes
Iliac crest
Thoracolumbar
fascia, posterior layer
Multifidus
Quadratus
lumborum
DDeep intrinsic back muscles. Removed: Superficial and intermediate
intrinsic back muscles (all); deep fascial layer and multifidus (right).
Revealed: Intertransversarii and quadratus lumborum (right).
29
Back
Muscle Facts (I)
Fig. 3.6 Short nuchal and craniovertebral joint muscles
Superior
nuchal line
Inferior
nuchal line
Rectus capitis
posterior minor
Obliquus
capitis superior
Mastoid process
②
①
Rectus capitis
posterior major
Posterior tubercle
of atlas (C1)
③
Transverse
process of atlas (C1)
Spinous process
of axis (C2)
Obliquus
capitis inferior
④
A
Posterior view, schematic.
B
Suboccipital muscles, posterior view.
Mastoid
process
Transverse process
of atlas (C1)
External occipital
protuberance
Mandible
Obliquus
capitis superior
Atlas (C1)
Rectus capitis
posterior minor
Axis (C2)
Rectus capitis
posterior major
Obliquus
capitis inferior
Spinous process
of axis (C2)
C
Suboccipital muscles, left lateral view.
Table 3.1
Short nuchal and craniovertebral joint muscles
Muscle
Rectus capitis
posterior
Origin
Insertion
① Rectus capitis
C2 (spinous
process)
Occipital bone (inferior nuchal line, middle
third)
② Rectus capitis
C1 (posterior
tubercle)
Occipital bone (inferior nuchal line, inner
third)
posterior major
posterior minor
③ Obliquus capitis C1 (transverse
Obliquus
capitis
superior
④ Obliquus capitis C2 (spinous
inferior
30
process)
process)
Occipital bone (inferior nuchal line, middle
third; above rectus capitis posterior major)
C1 (transverse process)
Innervation
C1
(posterior
ramus =
suboccipital n.)
Action
Bilateral: Extends head
Unilateral: Rotates head to same side
Bilateral: Extends head
Unilateral: Flexes head to same side; rotates
to opposite side
Bilateral: Extends head
Unilateral: Rotates head to same side
Occipital bone,
basilar portion
3 Muscles
Fig. 3.7 Prevertebral muscles
Rectus
capitis anterior
Occipital bone,
basilar portion
①
Atlas (C1)
③
④
Axis (C2)
Rectus
capitis lateralis
Mastoid
process
②
Transverse process
of atlas (C1)
Longus
capitis
C7 vertebra
T3 vertebra
Axis (C2)
A
Anterior view, schematic.
Superior
oblique
part
Anterior
tubercle
Vertical
part
Longus
colli
Inferior
oblique
part
C7 vertebra
1st rib
T3 vertebra
Prevertebral muscles, anterior view.
B
Removed: Longus capitis (left); cervical
viscera.
Table 3.2
Prevertebral muscles
Muscle
Origin
Insertion
Innervation
Action
① Longus capitis
C3–C6 (transverse processes,
anterior tubercles)
Occipital bone (basilar part)
Direct branches
from cervical plexus
(C1–C3)
Bilateral: Flexes head
Unilateral: Flexes and slightly rotates
head to same side
C5–T3 (anterior sides of
vertebral bodies)
C2–C4 (anterior sides of
vertebral bodies)
part
C3–C5 (transverse processes,
anterior tubercles)
C1 (transverse process,
anterior tubercle)
Inferior oblique
part
T1–T3 (anterior sides of
vertebral bodies)
C5–C6 (transverse processes,
anterior tubercles)
Direct branches
from cervical plexus
(C2–C6)
Bilateral: Flexes cervical spine
Unilateral: Flexes and rotates cervical
spine to same side
C1 (lateral mass)
Occipital bone (basilar part)
C1 (transverse process)
Occipital bone (basilar part,
lateral to occipital condyles)
C1 (anterior ramus)
Bilateral: Flexion at atlanto-occipital joint
Unilateral: Lateral flexion at atlantooccipital joint
Vertical (medial)
part
② Longus colli Superior oblique
(cervicis)
③ Rectus capitis anterior
④ Rectus capitis lateralis
31
Back
Muscle Facts (II)
The intrinsic back muscles are divided into superficial, intermediate,
and deep layers. The serratus posterior muscles are extrinsic back
muscles, innervated by the anterior rami of intercostal nerves, not
Superficial intrinsic back muscles
Table 3.3
Muscle
Serratus
posterior
Splenius
the posterior rami, which innervate the intrinsic back muscles. They
are included here as they are encountered in dissection of the back
musculature.
Origin
Insertion
Innervation
Action
①
erratus posterior
S
superior
Nuchal lig.; C7–T3 (spinous
processes)
2nd–4th ribs (superior borders)
Spinal nn. T2–T5
(anterior rami)
Elevates ribs
②
erratus posterior
S
inferior
T11–L2 (spinous processes)
8th–12th ribs (inferior borders,
near angles)
Spinal nn. T9–T12
(anterior rami)
Depresses ribs
③ S
plenius capitis
Nuchal lig.; C7–T3 or T4 (spinous
processes)
Lateral 1/3 nuchal line (occipital
bone); mastoid process
(temporal bone)
④ S
plenius cervicis
T3–T6 or T7 (spinous processes)
C1–C3/4 (transverse processes)
Spinal nn. C1–C6
(posterior rami,
lateral branches)
Bilateral: Extends cervical spine and
head
Unilateral: Laterally flexes and
rotates head to the same side
Fig. 3.8 Superficial intrinsic back
muscles, schematic
Fig. 3.9 Intermediate intrinsic back muscles, schematic
Right side, posterior view. These muscles are collectively known as the erector spinae.
Right side, posterior view.
③
⑧
⑤
④
①
⑨
⑪
⑥
⑩
②
A
Serratus
posterior.
Table 3.4
32
A
Iliocostalis
muscles.
B
Longissimus
muscles.
C
Spinalis
muscles.
Intermediate intrinsic back muscles (erector spinae)
Origin
Insertion
⑤ Iliocostalis cervicis
3rd–7th ribs
C4–C6 (transverse processes)
⑥ Iliocostalis thoracis
7th–12th ribs
1st–6th ribs
⑦ Iliocostalis lumborum
Sacrum; iliac crest;
thoracolumbar fascia
(posterior layer)
6th–12th ribs; thoracolumbar fascia
(posterior layer); upper lumbar
vertebrae (transverse processes)
⑧ Longissimus capitis
T1–T3 (transverse processes);
C4–C7 (transverse and
articular processes)
Temporal bone (mastoid process)
⑨ Longissimus cervicis
T1–T6 (transverse processes)
C2–C5 (transverse processes)
⑩ Longissimus thoracis
Sacrum; iliac crest; lumbar
vertebrae (spinous processes);
lower thoracic vertebrae
(transverse processes)
2nd–12th ribs; thoracic and lumbar
vertebrae (transverse processes)
⑪ Spinalis cervicis
C5–T2 (spinous processes)
C2–C5 (spinous processes)
Iliocostalis
Spinalis
⑦
B
Splenius
muscles.
Muscle
Longissimus
⑫
⑫ Spinalis thoracis
T10–L3 (spinous processes,
lateral surfaces)
T2–T8 (spinous processes, lateral
surfaces)
Innervation
Action
Spinal nn. C8–L1
(posterior rami,
lateral branches)
Bilateral: Extends spine
Unilateral: Flexes spine laterally
to same side
Bilateral: Extends head
Unilateral: Flexes and rotates
head to same side
Spinal nn. C1–L5
(posterior rami,
lateral branches)
Spinal nn.
(posterior rami)
Bilateral: Extends spine
Unilateral: Flexes spine laterally
to same side
Bilateral: Extends cervical
and thoracic spine
Unilateral: Flexes cervical and
thoracic spine to same side
Fig. 3.10 Superficial and intermediate intrinsic back muscles
Posterior view.
3 Muscles
Superior
nuchal line
Mastoid
process
Splenius
capitis
Spinous process of C7
Splenius
cervicis
Serratus
posterior
superior
4th rib
Longissimus capitis
8th rib
Spinalis
cervicis
Serratus
posterior
inferior
Iliocostalis cervicis
Longissimus cervicis
12th rib
L2
Iliocostalis
thoracis
Spinalis
thoracis
Longissimus
thoracis
A
Superficial back muscles:
Splenius and serratus posterior muscles.
Iliocostalis
lumborum
B
Intermediate intrinsic back muscles (erector spinae): Iliocostalis,
longissimus, and spinalis muscles.
33
Back
Muscle Facts (III)
The deep intrinsic back muscles are divided into two groups: trans­
versospinalis and deep segmental muscles. The transversospinalis
Table 3.5
muscles pass between the transverse and spinous processes of the
vertebrae.
Transversospinalis muscles
Muscle
Origin
Insertion
Innervation
① Rotatores breves
T1–T12 (between transverse and spinous processes of
adjacent vertebrae)
② Rotatores longi
T1–T12 (between transverse and spinous processes, skipping
one vertebra)
Rotatores
Sacrum, ilium, mamillary
processes of L1–L5,
transverse and articular
processes of T1–T4, C4–C7
Superomedially to spinous
processes, skipping two to
four vertebrae
④ Semispinalis capitis
C4–T7 (transverse and
articular processes)
Occipital bone (between
superior and inferior nuchal
lines)
⑤ Semispinalis cervicis
T1–T6 (transverse processes)
C2–C5 (spinous processes)
⑥ Semispinalis thoracis
T6–T12 (transverse processes)
C6–T4 (spinous processes)
Multifidus ③
Semispinalis
Action
Bilateral: Extends thoracic spine
Unilateral: Rotates thoracic spine to opposite
side
Spinal nn.
(posterior
rami)
Fig. 3.11 Transversospinalis muscles
Bilateral: Extends spine
Unilateral: Flexes spine to same side, rotates
it to opposite side
Bilateral: Extends thoracic and cervical spines
and head (stabilizes craniovertebral joints)
Unilateral: Flexes head, cervical and thoracic
spines to same side, rotates to opposite side
Fig. 3.12 Deep segmental muscles
Posterior view, schematic.
Posterior view, schematic.
④
⑦
⑤
⑫
A
③
②
⑥
⑬
⑧
Rotatores
A
muscles.
Table 3.6
B Multifidus.
Intertransversarii*
Levatores
costarum
⑪
C Semispinalis.
Origin
Insertion
⑦ Interspinales cervicis
C1–C7 (between spinous processes of adjacent vertebrae)
⑧ Interspinales lumbora
L1–L5 (between spinous processes of adjacent vertebrae)
Anterior intertransversarii
cervices
C2–C7 (between anterior tubercles of adjacent vertebrae)
⑨P
osterior intertransversarii
cervices
C2–C7 (between posterior tubercles of adjacent vertebrae)
⑩ Medial intertransversarii
lumbora
L1–L5 (between mammillary processes of adjacent vertebrae)
⑪ Lateral intertransversarii
lumbora
L1–L5 (between transverse processes of adjacent vertebrae)
⑫ Levatores costarum breves
⑬ Levatores costarum longi
Costal angle of next lower rib
C7–T11 (transverse processes)
Costal angle of rib two
vertebrae below
Innervation
Action
Spinal nn.
(posterior
rami)
Extends cervical and lumbar spines
Spinal nn.
(anterior rami)
Spinal nn.
(posterior
rami)
Bilateral: Stabilizes and extends the
cervical and lumbar spines
Unilateral: Flexes the cervical and
lumbar spines laterally to same side
Spinal nn.
(anterior rami)
Spinal nn.
(posterior
rami)
Bilateral: Extends thoracic spine
Unilateral: Flexes thoracic spine to
same side, rotates to opposite side
*Both the interspinales and intertransversarii muscles traverse the entire spine; only their clinically relevant components have been included.
34
⑩
Deep segmental back muscles
Muscle
Interspinales*
⑨
Fig. 3.13 Deep intrinsic back muscles
Superior
nuchal line
3 Muscles
Inferior
nuchal line
Posterior view.
Semispinalis
capitis
Semispinalis
cervicis
Spinous process of C7
Semispinalis
thoracis
Transverse
process
Spinous process
Rotatores
longi
Interspinales cervicis
Posterior intertransversarii cervices
Rotatores
breves
Transverse processes
Levatores
costarum
longi
Multifidus
Levatores
costarum
breves
Sacrum
Medial intertransversarii lumbora
A
Transversospinalis muscles: Rotatores,
multifidus, and semispinalis.
Interspinales lumbora
Lateral intertransversarii lumbora
B
Deep segmental muscles: Interspinales,
intertransversarii, and levatores costarum.
35
4
Neurovasculature
Back
Arteries & Veins of the Back
Internal
carotid a.
Fig. 4.1 Arteries of the back
External
carotid a.
The structures of the back are supplied by branches of the posterior
intercostal arteries, which arise from the thoracic aorta or from the
subclavian artery.
Right common carotid a.
Right subclavian a.
Vertebral a.
Brachiocephalic trunk
Right common
carotid a.
Aortic arch
Posterior intercostal aa.
Anterior intercostal aa.
Thoracic
aorta
Right subclavian a.
1st posterior
intercostal a.
Internal
thoracic a.
2nd posterior
intercostal a.
Abdominal
aorta
A
Arteries of the
trunk, right lateral
view.
Thyrocervical trunk
Costocervical
trunk
Subcostal a.
B
Vascular supply to the nuchal region, posterolateral view. Note: The first and second
posterior intercostal arteries arise from
the costocervical trunk, a branch of the
subclavian artery.
External iliac a.
Sternal brs.
Lateral
cutaneous br.
Dorsal branch of
posterior intercostal a.
Anterior
cutaneous br.
Spinal br.
Internal
thoracic a.
Posterior
intercostal a.
Medial
cutaneous br.
Anterior
intercostal a.
Thoracic
aorta
Posterior intercostal a.
Abdominal
aorta
Median
sacral a.
Lateral
cutaneous br.
C
Posterior intercostal arteries, oblique posterosuperior view. The posterior intercostal
arteries give rise to cutaneous and muscular branches, as well as spinal branches that
supply the spinal cord.
Common iliac a.
External iliac a.
Internal iliac a.
Lateral
sacral a.
Coccyx
DVascular supply to the sacrum, anterior view.
36
Fig. 4.2 Veins of the back
4 Neurovasculature
The veins of the back drain into the azygos vein via the posterior intercostal veins, hemiazygos vein, and ascending lumbar veins. The interior
of the spinal column is drained by the vertebral venous plexus that runs
the length of the spine.
Right internal jugular v.
Right subclavian v.
Right brachiocephalic v.
Azygos v.
Superior vena cava
Superior
sagittal sinus
Transverse sinus
Posterior intercostal vv.
Sigmoid sinus
Anterior intercostal vv.
Inferior vena cava
Subcostal v.
Emissary v.
External vertebral
venous plexus
Internal jugular v.
Left
brachiocephalic v.
Right
brachiocephalic v.
Superior
vena cava
Accessory
hemiazygos v.
External iliac v.
A
Veins of the
trunk, right lateral
view.
Azygos v.
Posterior
intercostal vv.
Hemiazygos v.
External vertebral
venous plexus
Lateral
cutaneous br.
Posterior internal
vertebral venous plexus
Medial
cutaneous br.
Lumbar v.
Ascending lumbar v.
Posterior intercostal v.
Posterior internal
vertebral venous plexus
Anterior internal
vertebral
venous plexus
Anterior
internal
vertebral
venous
plexus
Azygos v.
Anterior external
vertebral
venous plexus
Intervertebral v.
Hemiazygos v.
C Intercostal veins and anterior vertebral venous plexus, anterosuperior view. The intercostal veins follow a similar course to the intercostal nerves and arteries (see pp. 36, 38). Note: The anterior external
vertebral venous plexus can be seen communicating with the azygos
vein.
External
iliac v.
Internal
iliac v.
B
Vertebral venous plexus, posterior view with vertebral canal windowed in the lumbar and sacral spine. The external vertebral venous
plexus communicates with the sigmoid sinus through emissary
veins in the skull. The external vertebral venous plexus is divided into
an anterior and a posterior portion that run along the exterior of
the vertebral column. The anterior and posterior internal vertebral
venous plexus run in the vertebral foramen and drain the spinal cord.
37
Back
Nerves of the Back
The back receives its innervation from branches of the spinal nerves. The
posterior (dorsal) rami of the spinal nerves supply most of the intrinsic
muscles of the back. The extrinsic muscles of the back are supplied by
the anterior (ventral) rami of the spinal nerves.
Fig. 4.3 Nerves of the back
Cross section of the vertebral column and spinal cord with surrounding
musculature, superior view.
Esophagus
Aorta
Sympathetic
(paravertebral)
ganglion
Outer layer,
dura mater
White and
gray rami
communicans
Anterior root
Meningeal br.
Inner layer,
arachnoid mater
Spinal ganglion
Posterior root
Spinal n.
Medial
cutaneous br.
Lateral
cutaneous br.
38
Anterior (ventral)
ramus
Posterior (dorsal)
ramus
Fig. 4.4 Nerves of the nuchal region
Right side, posterior view.
Nerves of the nuchal region
Posterior
(dorsal)
ramus
Anterior
(ventral)
ramus
Function
Suboccipital n.
(C1)
Innervates the rectus capitis posterior major
and minor; and obliquus capitis superior and
inferior
Greater
occipital n.
(C2)
Assits in the innervation of the semispinalis
capitis muscle and supplies skin behind the
auricle and the scalp to the coronal suture
Third occipital
n. (C3)
Assists in the innervation of the semispinalis
capitis muscle, the C2-C3 facet joint, and
supplies a small area of skin just below the
superior nuchal line
Lesser occipital
n. (C2)
Cutaneous only, supplies an area of scalp
posterolateral to the auricle, and the skin on the
upper third of the medial aspect of the auricle
3rd occipital n. (C3)
Greater
auricular n.
(C2, C3)
Cutaneous only, supplies an area of skin over
the parotid gland, the majority of the pinna,
lateral neck, and posterior to the auricle
Supraclavicular nn.
Lesser
occipital n.
4 Neurovasculature
Table 4.1
Branches
Suboccipital n. (C1)
Great auricular n.
Greater occipital n. (C2)
**The anterior rami of C1-C3 also give rise to the ansa cervicalis, which
innervates the infrahyoid muscles (see p. 524).
C5 spinal n.,
posterior ramus
Fig. 4.5 Cutaneous innervation of the back
Color denotes the skin areas innervated by (A) particular peripheral
nerves or (B) particular pairs of segmental spinal nerves. Patterns
of loss of cutaneous sensation can be helpful in diagnosis of nerve
lesions.
Greater
occipital n.
C2
Lesser occipital n.
C3
C5
C8
T1
Great auricular n.
C4
Supraclavicular nn.
C5
Medial
cutaneous brs.
Axillary n.
Spinal nn.,
(posterior
rami)
C6
Lateral
cutaneous brs.
T1
Intercostal nn.,
(anterior rami,
lateral cutaneous brs.)
L1
Superior
clunial nn.
Middle clunial nn.
Iliohypogastric n.
A
Cutaneous innervation patterns of specific peripheral nerves.
Dermatomes: Dermatomes are bilateral band-like areas of skin reB
ceiving innervation from a single pair of spinal nerves (from a single
segment of the spinal cord). Note: Spinal nerve C1 is purely motor;
consequently there is no C1 dermatome.
39
Back
Spinal Cord
terminates at the foramen magnum and is replaced in the vertebral
canal with the periosteum of the vertebral bone. Due to this structural
difference in the two regions, the dural sac is not adherent to the bone
of the vertebral canal as it is in the cranial cavity.
The dura mater of the cranial cavity is composed of two layers, the
periosteal and meningeal. Only the meningeal layer extends into the
vertebral canal with the spinal cord. The periosteal layer of dura
Fig. 4.6 Spinal cord in situ
Posterior view with vertebral canal windowed.
C1 spinal n.
Atlas (C1)
Vertebra
prominens
(C7)
T1 spinal n.
Medulla
oblongata
Cervical
enlargement
Fig. 4.7 Spinal cord
and its meningeal
layers
Posterior view. The dura
mater is opened and the
arachnoid is sectioned.
The detailed anatomy of
the spinal cord can be
found on pp. 690–691.
Spinal cord
Anterior spinal a.
Anterior spinal vv.
Pia mater
Subarachnoid space
Posterior root
Spinal ganglion
Arachnoid
(mater)
Subdural
space
Dura mater
Posterior ramus
Anterior ramus
Anterior
root
Spinal n.
White and gray
rami communicans
Denticulate
lig.
Anterior
rootlets
T12 vertebra
L1 spinal n.
Lumbosacral
enlargement
Conus
medullaris
Cauda equina
L5 vertebra
S1 spinal n.
Dura mater
Arachnoid
(mater)
Fig. 4.8 Cervical
spinal cord in situ:
Transverse section
Epidural space
Superior view. Spinal cord
at level of C4 ­vertebra.
Posterior internal
vertebral
venous plexus
Subarachnoid
space
Arachnoid
(mater)
Dura mater
Denticulate
lig.
Intervertebral
foramen
Posterior
root
Anterior
root
Spinal
ganglion
Spinal n.
Vertebral a.
Vertebral vv.
Sacral hiatus
Anterior internal
vertebral venous plexus
Root
sleeve
Clinical box 4.1
Spina Bifida
Spina bifida is a neural tube defect that occurs when the spine and spinal cord
do not form properly. In the United States, it affects about one out of every
1,500 newborns. There are three main types.
• Spina bifida occulta (A) is the most common congenital anomaly of the
vertebral column in which the laminae of L5 and/or S1 fail to develop. The
defect is often hidden and most individuals are unaware they have the
condition because there is only a small defect in the vertebrae. There is
generally no disturbance of spinal function.
• Spina bifida (meningocele) (B) occurs when one or more vertebral arches
fail to develop and presents with a herniation or sac of only the meninges.
The spinal cord and nerves are normal and not severely affected.
40
• Spina bifida (myelomeningocele) (C) occurs when multiple vertebral
arches fail to develop resulting in a herniation of both the meninges and
spinal nerves. This is the most severe form exposing the newborn to life
threatening infections, bowel and bladder dysfunction, and total paralysis
of the lower extremities.
A
B
C
Fig. 4.9 Cauda equina in the vertebral canal
Fig. 4.10 Cauda equina in situ: Transverse section
Posterior view. The lamina and posterior surface of the sacrum have
been partially removed.
Superior view. Cauda equina at level of L2 vertebra.
Fatty tissue
Epidural space
Conus
medullaris
Cauda equina
Spinal
ganglion
Dural sac
Spinal
ganglion
Spinal
dura mater
Cauda equina
(posterior and
anterior spinal
roots)
4 Neurovasculature
Posterior
internal vertebral
venous plexus
L1 vertebra
Anterior
internal vertebral
venous plexus
Dura mater
Arachnoid
(mater)
Clinical box 4.2
Sacral hiatus
Fig. 4.11 Spinal cord, dural
sac, and vertebral column
at different ages.
Anterior view. Longitudinal
growth of the spinal cord lags behind that of the vertebral column.
At birth, the distal end of the
spinal cord, the conus medullaris,
is at the level of the L3 vertebral
body, but in the average adult it
extends to the level of L1/L2. The
dural sac always extends into the
upper sacrum.
Lumbar puncture
Filum terminale
Conus
medullaris
(adult)
A needle introduced into the dural sac (lumbar cistern) generally slips past
the spinal nerve roots without injuring the spinal cord or spinal nerves.
Cerebrospinal fluid (CSF) samples are therefore taken between the L3 and L4
vertebrae (2), once the patient has leaned forward to separate the spinous
processes of the lumbar spine.
T 12
Conus
medullaris
Cauda
equina
L1
1
2
Conus
medullaris
(newborn)
Dural sac
(lumbar
cistern)
Sacral
hiatus
3
Anesthesia
Lumbar anesthesia may be administered in a similar fashion (2). Epidural
anesthesia is administered by placing a catheter in the epidural space
without penetrating the dural sac (1). This may also be done by passing a
needle through the sacral hiatus (3).
41
Back
Spinal Cord Segments & Spinal Nerves
Fig. 4.12 Spinal cord segment
The spinal cord consists of 31 segments, each innervating a specific area of the skin (a dermatome) of
the head, trunk, or limbs. Afferent (sensory) posterior rootlets and efferent (motor) anterior rootlets
form the posterior and anterior roots of the spinal nerve for that segment. The two roots fuse to
form a mixed (motor and sensory) spinal nerve that exits the intervertebral foramen and immediately
thereafter divides into an anterior and posterior ramus.
Posterior rootlets
Gray matter,
posterior horn
Posterior root (with
spinal ganglion)
Spinal n.
White matter
Posterior ramus
Gray matter,
anterior horn
Anterior ramus
Fig. 4.13 Spinal cord segments, dermatomes,
and effects of spinal cord lesions
Anterior
root
The spinal cord is divided into four major regions: cervical,
thoracic, lumbar, and sacral. The regions of the spinal cord
are designated by colors: red, cervical; brown, thoracic;
green, lumbar; blue, sacral.
Spinal cord segment
C1
Meningeal br.
Anterior
rootlets
Splanchnic nn.
Vertebra
Atlas (C1)
Axis (C2)
Gray ramus
communicans
White ramus
communicans
Sympathetic
(paravertebral)
ganglion
Sympathetic trunk
T2
C8
T1
S1
L5
L1
C2
T1
C7
T1
C3
Cervical cord
lesion
C4
C5
T12
L1
S1
C6
S5
T1
T12
Thoracic cord
lesion
L1
C7
L5
C8
Lumbar cord
lesion
S1
Coccyx
A
Spinal cord segments. Initially spinal nerves
pass out above the vertebrae for which they
are numbered. However, since there is an
8th cervical spinal nerve but no 8th cervical
vertebrae, C8 passes out above vertebral
level T1, and the spinal nerve for T1, and
those following, pass out below the vertebral level for which they are numbered.
42
Conus/cauda
equina lesion
B
Dermatomes, band-like areas of skin receiving sensory innervation from a single pair
of spinal nerves (from a single segment of
the spinal cord). Note: Spinal nerve C1 is
purely motor; consequently there is no C1
dermatome.
C
Effects of lesions in each region of the
spinal cord.
Fig. 4.14 Spinal nerve branches
4 Neurovasculature
Anterior
cutaneous br.
Posterior
ramus
Spinal cord
Articular br.
Spinal ganglion
White and gray
rami communicans*
Sympathetic ganglion
Sympathetic trunk
Lateral
cutaneous br.
Meningeal br.
Anterior
ramus
Lateral br.
Medial br.
Anterior
sacral
foramen
Anterior
root
A Superolateral view of a thoracic spinal nerve. The posterior (dorsal) rami of the spinal nerves give rise to muscular and cutaneous
branches, as well as articular branches to the zygapophyseal joints.
The anterior (ventral) rami of the spinal nerves form the cervical
plexus (C1–C4), the brachial plexus (C5–T1), the lumbar plexus
(T12–L4), and the sacral plexus (L4–S3). The anterior rami of spinal
nerves T1–T11 produce the intercostal nerves (T12 produces the
subcostal nerve).
Anterior ramus
(to sacral plexus)
Spinal
ganglion
Posterior
ramus
Cauda
equina
Posterior
root
Posterior
sacral
foramen
Lateral br.
(to the clunial
nerves)
B Spinal nerve branches in the sacral foramina.
Superior view of transverse section through
right half of sacrum.
Table 4.2
Branches of a spinal nerve
Branches
Territory
Meningeal br.
Posterior
(dorsal)
ramus
Spinal meninges; ligaments of spinal column
Medial brs.
Zygapophyseal joints
Muscular br.
Intrinsic back muscles
Cutaneous br.
Lateral brs.
Anterior (ventral)
ramus
Articular br.
Cutaneous br.
Muscular br.
Skin of posterior head, neck, back, and buttocks
Intrinsic back muscles
Lateral cutaneous brs.
Skin of lateral chest wall
Anterior cutaneous brs.
Skin of anterior chest wall
*The white and gray rami communicans carry pre- and postganglionic fibers between the sympathetic trunk and spinal n.
43
Back
Arteries & Veins of the Spinal Cord
Like the spinal cord itself, the arteries and veins of the spinal cord consist
of multiple horizontal systems (blood vessels of the spinal cord segments) that are integrated into a vertical system.
Fig. 4.15 Arteries of the spinal cord
Basilar a.
The unpaired anterior and paired posterior spinal arteries typically arise
from the vertebral arteries. As they descend within the vertebral canal,
the spinal arteries are reinforced by anterior and posterior segmental
medullary arteries. Depending on the spinal level, these reinforcing
branches may arise from the vertebral, ascending or deep cervical,
posterior intercostal, lumbar, or lateral sacral arteries.
Vertebral a.
Anterior
spinal a.
Posterior
spinal a.
Posterior spinal aa.
Vertebral a.
Anterior
segmental
medullary a.
Ascending
cervical a.
Posterior
segmental
medullary a.
Posterior horn
Anterior horn
Spinal br.
Subclavian a.
Sulcal a.
Anterior
spinal a.
Segmental a.
Vasocorona
Posterior
intercostal aa.
Posterior
segmental
medullary a.
Anterior
segmental
medullary a.
A
Spinal and segmental medullary arteries.
Posterior segmental
medullary a.
Medial
cutaneous br.
Posterior
segmental
medullary a.
Lateral
cutaneous br.
Posterior
intercostal a.
Spinal br.
Anterior segmental
medullary a.
Posterior
intercostal a.
B
Origins of the segmental medullary arteries. In the thorax, the segmental medullary
arteries arise from the spinal branch of the
posterior intercostal arteries (see p. 36).
44
Lumbar aa.
Posterior
(dorsal) br.
Thoracic
aorta
C
Arterial supply
system.
Great
anterior
segmental
medullary a.
Fig. 4.16 Veins of the spinal cord
Posterior
spinal v.
Sulcal v.
Venous
ring
Posterior
radicular v.
4 Neurovasculature
The interior of the spinal cord drains via venous plexuses into an anterior
and a posterior spinal vein. The radicular and spinal veins connect the
veins of the spinal cord with the internal vertebral venous plexus. The
intervertebral and basivertebral veins connect the internal and external
venous plexuses, which drain into the azygos system.
Spinal v.
Right deep
cervical v.
Anterior
spinal v.
Anterior
spinal v.
B
Spinal and
radicular
veins.
Posterior internal
vertebral venous plexus
Right
vertebral v.
Right
subclavian v.
Right internal
jugular v.
Superior
vena cava
Left brachiocephalic v.
Basivertebral v.
Anterior
radicular v.
Anterior external
vertebral venous plexus
C
Vertebral venous
plexuses.
Anterior spinal v.
Ascending lumbar v.
Intervertebral v.
Hemiazygos v.
Posterior
internal vertebral
venous plexus (in
epidural space)
Basivertebral v.
Inferior
vena cava
Common
iliac v.
Venous drainage
A
system.
Intervertebral v.
Subcostal v.
Posterior
radicular v.
Ascending
lumbar v.
Anterior
internal vertebral
venous plexus
Accessory
hemiazygos v.
Intercostal vv.
Azygos v.
Anterior radicular v.
Ascending
lumbar v.
Medial
and lateral
epidural vv.
Internal
iliac v.
DVeins in the sacral
and lumbar canals.
Anterior
internal vertebral
venous plexus
External
iliac v.
45
Back
Neurovascular Topography of the Back
Fig. 4.17 Neurovasculature of the
nuchal region
Posterior view. Removed: Trapezius, sternocleidomastoid, and semispinalis capitis.
Revealed: Suboccipital region.
Obliquus capitis
superior
Rectus capitis
posterior minor
Occipital a.
Greater occipital n.
Vertebral a.
Rectus capitis
posterior major
Suboccipital n.
3rd occipital n.
Atlas (C1),
transverse process
Obliquus capitis
inferior
Lesser occipital n.
Axis (C2),
spinous process
Great auricular n.
Sternocleidomastoid
Deep cervical a.
Longissimus
capitis
Semispinalis
cervicis
46
Semispinalis
capitis
Fig. 4.18 Neurovasculature of the back
4 Neurovasculature
Posterior view. Removed: Muscle fascia (except
posterior layer of thoracolumbar fascia); latissimus dorsi (right). Reflected: Trapezius (right).
Revealed: Transverse cervical artery in the deep
scapular region. See p. 72 for the course of the
intercostal vessels.
Dorsal
scapular n.
3rd
occipital n.
Transverse
cervical a.
Splenius capitis
Accessory n.
Rhomboid major
Trapezius
Spinal nn.,
posterior rami
(lateral
cutaneous brs.)
Deltoid
Thoracolumbar fascia,
posterior layer
Serratus posterior inferior
Intercostal nn. and
posterior intercostal
aa. and vv. (lateral
cutaneous brs.)
Latissimus dorsi
Fibrous lumbar triangle
(of Grynfeltt)
External oblique
Iliolumbar triangle
(of Petit)
Internal oblique
Iliac crest
Superior
clunial nn.
Middle
clunial nn.
Inferior clunial nn.
47
5
Sectional & Radiographic Anatomy
Back
Radiographic Anatomy of the Back (I)
Nuchal lig.
Cervical
vertebrae C1-C7
Dens of axis (C2)
Fig. 5.1 MRI of the spine
Sagittal view. (Reproduced from Moeller
TB, Reif E. Atlas of Sectional Anatomy: The
Musculoskeletal System. New York, NY:
Thieme; 2009.)
Vertebra prominens (C7)
Body of thoracic vertebra T1
Vertebral canal
Spinal cord (thoracic part)
Thoracic
vertebrae T1-T12
Intervertebral disk
Supraspinous lig.
Interspinous ligs.
Body of lumbar vertebra L1
Conus medullaris
Lumbar
vertebrae L1-L5
Cauda equina
Spinous process
Dural sac
Sacrum (sacral
vertebrae) S1-S5
Coccyx
(coccygeal vertebrae)
Co1-Co3 or Co4
Sacrum (S1)
Sacral
promontory
Coccyx
Thoracic vertebral body T12
Fig. 5.2 MRI of the lumbar spine
Parasagittal view. (Reproduced from
Moeller TB, Reif E. Atlas of Sectional
Anatomy: The Musculoskeletal System.
New York, NY: Thieme; 2009.)
Mammillary process
Erector spinae
Lumbar vertebral body L2
Inferior vena cava
Spinal ganglion L2
Lamina
Intervertebral disk L3/L4 (nucleus pulposus)
Superior articular process
Common iliac a.
Intervertebral
foramen
Inferior articular
process
Zygapophyseal
joint
Multifidus
Promontory of sacrum
Sacrum (S1)
48
Gluteus maximus
Fig. 5.3 Radiograph of the cervical spine
Lateral view. (Reproduced from Moeller TB, Reif E. Pocket Atlas
of Radiographic Anatomy, 3rd ed. New York, NY: Thieme; 2010.)
Odontoid process
Mandible
Body of the axis
Anterior superior margin of the vertebra
Anterior inferior margin of the vertebra
Base of the skull
Posterior arch of the atlas
Spinous process
Transverse process
5 Sectional & Radiographic Anatomy
Anterior arch of the atlas
Superior articular facet
Superior vertebral end plate
Inferior vertebral end plate
Inferior articular facet
Intervertebral facet joint
Intervertebral disk space
Articular pillar
Lamina
Spinous process
Trachea
Fig. 5.4 Radiograph of the thoracic spine
Anteroposterior view. Lower thoracic region. (Reproduced from
Moeller TB, Reif E. Pocket Atlas of Radiographic Anatomy, 3rd ed.
New York, NY: Thieme; 2010.)
Transverse process
Body of vertebra
Pedicle
Spinous process
Intervertebral disk
49
Back
Radiographic Anatomy of the Back (II)
Fig. 5.5 Radiograph of the
lumbar spine
Lateral view. (Reproduced from
Moeller TB, Reif E. Pocket Atlas of
Radiographic Anatomy, 3rd ed.
New York, NY: Thieme; 2010.)
Inferior vertebral end plate
Superior vertebral end plate
Pedicle
Intervertebral foramen
Facet joint
Invertebral disk space
Inferior articular process
Superior articular process
Promontory of sacrum
Fig. 5.6 Radiograph of the lumbar spine
Oblique view. (Reproduced from Moeller TB, Reif E. Pocket Atlas
of Radiographic Anatomy, 3rd ed. New York, NY: Thieme; 2010.)
Body of
vertebra
Body of
vertebra
Intervertebral
disk space
Ribs
Ipsilateral
transverse
process
Pedicle
Interarticular
part
Lamina
Contralateral
transverse process
Superior articular
process
Intervertebral
foramen
Intervertebral
disk space
Ribs
Ipsilateral
transverse
process
Pedicle
Inferior articular
process
Spinous process
A
50
B
Interarticular
part
Lamina
Contralateral
transverse process
Superior articular
process
Intravertebral
foramen
Inferior articular
process
Spinous process
Fig. 5.7 MRI of the sacrum I
Oblique view. (Reproduced from Moeller TB, Reif E. Atlas of Sectional
Anatomy: The Musculoskeletal System. New York, NY: Thieme; 2009.)
Ileum
Internal oblique
Iliac aa.
Transversus
abdominis
Psoas major
Iliacus
5th lumbar
nerve root
Anterior
sacroiliac ligs.
Gluteus medius
Gluteus maximus
Anterior sacral
foramina
Common iliac a. and v.
Descending colon
Ilium (wing)
L5 vertebra, body
Sacroiliac joint
Sacrum (lateral mass)
Interosseous sacroiliac
ligs.
5 Sectional & Radiographic Anatomy
External oblique
Posterior sacroiliac ligs.
Sacral canal
Fig. 5.8 MRI of the sacrum II
Oblique view. (Reproduced from Moeller TB, Reif E. Atlas of Sectional
Anatomy: The Musculoskeletal System. New York, NY: Thieme; 2009.)
Ascending colon
L5 vertebra, body
Sacrum (S1, body)
Descending colon
Psoas major
Iliacus
Dural sac
Ilium, wing
Posterior sacroiliac ligs.
Gluteus maximus
Spinal n. roots in
sacral spinal canal
51
Thorax
6 Surface Anatomy
Surface Anatomy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
7 Thoracic Wall
Thoracic Skeleton . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Sternum & Ribs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Joints of the Thoracic Cage . . . . . . . . . . . . . . . . . . . . . . . . . . .
Thoracic Wall Muscle Facts . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Diaphragm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Neurovasculature of the Diaphragm . . . . . . . . . . . . . . . . . . . .
Arteries & Veins of the Thoracic Wall . . . . . . . . . . . . . . . . . . . .
Nerves of the Thoracic Wall . . . . . . . . . . . . . . . . . . . . . . . . . . .
Neurovascular Topography of the Thoracic Wall . . . . . . . . . . .
Female Breast . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Lymphatics of the Female Breast . . . . . . . . . . . . . . . . . . . . . . .
56
58
60
62
64
66
68
70
72
74
76
8 Thoracic Cavity
Divisions of the Thoracic Cavity . . . . . . . . . . . . . . . . . . . . . . . .
Arteries of the Thoracic Cavity . . . . . . . . . . . . . . . . . . . . . . . . .
Veins of the Thoracic Cavity . . . . . . . . . . . . . . . . . . . . . . . . . . .
Lymphatics of the Thoracic Cavity . . . . . . . . . . . . . . . . . . . . . .
Nerves of the Thoracic Cavity . . . . . . . . . . . . . . . . . . . . . . . . .
78
80
82
84
86
9 Mediastinum
Mediastinum: Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88
Mediastinum: Structures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
Heart: Functions & Relations . . . . . . . . . . . . . . . . . . . . . . . . . . 92
Pericardium . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94
Heart: Surfaces & Chambers . . . . . . . . . . . . . . . . . . . . . . . . . . 96
Heart: Valves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
Arteries & Veins of the Heart . . . . . . . . . . . . . . . . . . . . . . . . . 100
Conduction & Innervation of the Heart . . . . . . . . . . . . . . . . . 102
Pre- & Postnatal Circulation . . . . . . . . . . . . . . . . . . . . . . . . . . 104
Esophagus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
Neurovasculature of the Esophagus . . . . . . . . . . . . . . . . . . . 108
Lymphatics of the Mediastinum . . . . . . . . . . . . . . . . . . . . . . . 110
10 Pulmonary Cavities
Pulmonary Cavities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Pleura: Subdivisions, Recesses & Innervation . . . . . . . . . . . .
Lungs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Bronchopulmonary Segments of the Lungs . . . . . . . . . . . . .
Trachea & Bronchial Tree . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Respiratory Mechanics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Pulmonary Arteries & Veins . . . . . . . . . . . . . . . . . . . . . . . . . .
Neurovasculature of the Tracheobronchial Tree . . . . . . . . . .
Lymphatics of the Pleural Cavity . . . . . . . . . . . . . . . . . . . . . .
112
114
116
118
120
122
124
126
128
11 Sectional & Radiographic Anatomy
Sectional Anatomy of the Thorax . . . . . . . . . . . . . . . . . . . . . .
Radiographic Anatomy of the Thorax (I). . . . . . . . . . . . . . . . .
Radiographic Anatomy of the Thorax (II). . . . . . . . . . . . . . . .
Radiographic Anatomy of the Thorax (III). . . . . . . . . . . . . . . .
130
132
134
136
6
Surface Anatomy
Thorax
Surface Anatomy
Fig. 6.1 Regions of the thorax
Presternal
region
Anterior view.
Infraclavicular
fossa
Clavipectoral
triangle
Deltoid region
Axillary region
Pectoral region
Inframammary
region
Lateral
pectoral region
Epigastric
region (epigastrium)
Hypochondriac
region
Midclavicular
line (MCL)
Fig. 6.2 Palpable structures of the thorax
Anterior view.
Coracoid
process
Supraclavicular
fossa
Clavicle,
medial head
Greater and
lesser tubercles
Sternal
angle
Xiphoid
process
A
Bony prominences.
Subcostal
plane
Sternocleidomastoid
Supraclavicular fossa
Deltoid
Deltopectoral
groove
Pectoralis major
Serratus anterior
B
Musculature.
54
Thyroid cartilage
Jugular notch
Fig. 6.3 Vertical reference lines of the thorax
6 Surface Anatomy
Anterior
axillary line
Anterior
midline
Sternal
line
Parasternal
line
Posterior axillary
line
Midaxillary
line
Anterior axillary
line
Midclavicular line
A
Anterior view.
B
Right lateral view.
Fig. 6.4 Pleural cavities and lungs projected
onto the thoracic skeleton
Cervical pleura
(cupola)
Costomediastinal
recesses of pleural cavities
Parietal pleura
Right lung
Left lung
Inferior
border of
lung
Inferior
border of
lung
Costodiaphragmatic
recesses of
pleural cavities
A
Anterior view.
Parietal
pleura
Left lung
Right lung
Costodiaphragmatic
recesses of
pleural cavities
Posterior view.
B
55
7
Thoracic Wall
Thorax
Thoracic Skeleton
The thoracic skeleton consists of 12 thoracic vertebrae (p. 10), 12 pairs
of ribs with costal cartilages, and the sternum. In addition to participating in respiratory movements, it provides a measure of protection to
vital organs. The female thorax is generally narrower and shorter than
the male equivalent.
Fig. 7.1 Thoracic skeleton
Clavicular
notch
Superior
thoracic aperture
Jugular notch
Manubrium
Sternal angle
Sternum
Body
Xiphoid process
Costal
cartilage
1st rib
Clavicular
notch
Costal margin
(arch)
Sternum
Inferior
thoracic aperture
Vertebral
body, T1
Spinous process,
T1
Intervertebral
disk
A
Anterior view.
T1 spinous process
Costal
cartilage
Costal margin
(arch)
Costal
tubercle
Costal angle
Transverse
process
Costotransverse
joint
Spinous
process, T12
12th rib
C
Posterior view.
56
Spinous process, L1
B
Left lateral view.
Vertebral
body, T12
12th rib
Vertebral
body, L1
7 Thoracic Wall
Fig. 7.2 Structure of a thoracic segment
Superior view of 6th rib pair.
Costal
angle
Spinous
process
Transverse
process
Costal
tubercle
Neck
of rib
Vertebral
foramen
Vertebral
body
Head
of rib
Body (shaft)
of rib
Elements of a thoracic segment
Table 7.1
Vertebra
Costal
cartilage
Head
Bony part (costal bone)
Rib
Neck
Costal tubercle
Body (including costal angle)
Costal part (costal cartilage)
Sternum
Sternum (articulates with costal cartilage of true ribs only; see Fig. 7.3)
Fig. 7.3 Types of ribs
Left lateral view.
Rib type
Ribs
Anterior articulation
True ribs
1–7
Sternum (costal notches)
False ribs
8–10
Rib above
Floating ribs
11, 12
None
57
Thorax
Sternum & Ribs
Fig. 7.4 Sternum
The sternum is a dagger-like bone consisting of the manubrium (the
handle), body (blade), and xiphoid process (tip of blade). The junction
of the manubrium and body (the sternal angle) is typically elevated and
marks the articulation of the second rib. The sternal angle (projected
posteriorly to intersect with T4/5) is an important landmark for internal
structures.
Jugular
notch
Clavicular
notch
Manubrium
Sternal
angle
Clavicular
notch
1st costal
notch
Manubrium
Body
Sternal
angle
Xiphoid
process
Body
A
Anterior view.
2nd through
7th costal
notches
Xiphoid
process
B
Left lateral view. The costal notches are
sites of articulation with the costal cartilage
of the true ribs (see Fig. 7.3).
58
Fig. 7.5 Ribs
12th
rib
Supraspinous fossa
Right ribs, superior view. See pp. 298–299
for joints of the shoulder.
7 Thoracic Wall
Scapular
notch
Acromion
Acromioclavicular joint
Dens of axis (C2)
Atlas (C1)
1st rib
Coracoid
process
Sternoclavicular
joint
Clavicle
5th rib
2nd rib
Manubrium
A
Variations in rib size and shape.
Costal
tubercle
Costal
angle
Crest
of neck
Neck
Head
Costal
tubercle
Crest
of neck
Costal
tubercle
Head
Neck
Head
Tuberosity
for serratus
anterior
Neck
Costal
angle
Head
Groove for
subclavian a.
Tubercle for
anterior scalene
Groove for
subclavian v.
2nd rib
Body
(shaft)
Body
(shaft)
B
1st rib. Most ribs have a costal groove
along the inferior border (See Fig. 7.24),
which protects the intercostal vessels and
nerves.
11th rib
5th rib
C
Right ribs, superior view.
59
Thorax
Joints of the Thoracic Cage
The diaphragm is the chief muscle for quiet respiration (see p. 64).
The muscles of the thoracic wall (see p. 62) contribute to deep (forced)
inspiration.
Fig. 7.6 Rib cage movement
on the diagrams are longer than the blue ones (expiration dimensions)
below. The downward movement of the diaphragm further increases
the volume of the thoracic cavity.
Full inspiration (red); full expiration (blue). In deep inspiration, there is
an increase in transverse and anteroposterior (AP) dimensions, as well
as the infrasternal angle. Note the red lines (inspiration dimensions)
Infrasternal
angle
Infrasternal
angle
Inspiration
Anteroposterior
(AP) dimension
Anteroposterior
(AP) dimension
Transverse thoracic
dimension
Transverse thoracic
dimension
Expiration
A
Anterior view.
B
Left lateral view.
Axis of
movement
C
Position of diaphragm during respiration.
Blue line = expiration, red line = inspiration.
Axis of
movement
Neck
of rib
Upper rib
Increase in
transverse
dimension
Lower rib
Increase in
Anteroposterior (AP)
dimension
DAxes of rib movement, superior view.
60
Fig. 7.7 Sternocostal joints
7 Thoracic Wall
Anterior view with right half of sternum sectioned frontally. True joints
are generally found only at ribs 2 to 5; ribs 1, 6, and 7 attach to the
sternum by synchondroses.
Clavicular
notch
1st rib
Sternum
Fig. 7.8 Costovertebral joints
Radiate
sternocostal
ligs.
Two synovial joints make up the costovertebral articulation of each rib.
The costal tubercle of each rib articulates with the costal facet of its
accompanying vertebra (A). The head of most ribs articulates with the
vertebra of its own number and the vertebra immediately superior. Ribs
1, 11, and 12 typically articulate only with their own vertebrae.
Joint space
Costal
cartilage
Costoxiphoid
lig.
Xiphoid
process
Superior
articular facet
Facet for rib
tubercle
Lateral costotransverse lig.
Costotransverse
joint
Costal tubercle,
articular surface
Superior costotransverse lig. (cut)
Costal tubercle
Neck of 8th rib
Costotransverse
lig.
Radiate
lig.
Joint of head of rib
Intervertebral
disk
T8
Transverse process
T5
Costotransverse
lig. (cut)
Costal facets
Facet for rib
tubercle
A
Costotransverse joint. Superior view with
joints of the left rib transversely sectioned.
Lateral costotransverse lig. (cut)
Spinous process
Intra-articular
lig.
Crest of
rib head
Intervertebral
disk
Radiate
lig.
Articular facets
(on head of 7th rib)
Superior
costotransverse
lig.
Costal tubercle
8th rib (neck)
T8
B
Costovertebral joints. Left lateral view with the joint head of the 7th
rib viewed in sagittal section..
61
Thorax
Thoracic Wall Muscle Facts
the shoulder (see pp. 318–319), and the serratus posterior is discussed
with the back (see p. 32).
The muscles of the thoracic wall are primarily responsible for ribcage
movement during ­respiration, although other muscles aid in deep inspiration: the pectoralis major and serratus anterior are discussed with
Fig. 7.9 Muscles of the thoracic wall
④
②
①
⑥
⑦
③
⑤
⑤
⑥
B
Intercostal muscles, anterior view.
A
Scalene muscles, anterior view.
Muscle
Intercostal
mm.
Origin
Insertion
Innervation
① Anterior scalene m.
C3–C6 (transverse processes,
anterior tubercles)
1st rib (anterior scalene
tubercle)
Anterior rami of
C4–C6 spinal nn.
② Middle scalene m.
C1–C2 (transverse processes)
C3–C7 (transverse processes,
posterior tubercles)
1st rib (posterior to groove
for subclavian a.)
Anterior rami of
C3–C8 spinal nn.
③ Posterior scalene m.
C5–C7 (transverse processes,
posterior tubercles)
2nd rib (outer surface)
Anterior rami of
C6–C8 spinal nn.
④ External intercostal
mm.
Lower margin of rib to upper margin of next lower rib (courses
obliquely forward and downward from costal tubercle to
chondro-osseous junction)
⑤ Internal intercostal
mm.
⑥ Innermost
intercostal mm.
62
C
Transversus thoracis, posterior view.
Muscles of the thoracic wall
Table 7.2
Scalene
mm.
④
Lower margin of rib to upper margin of next lower rib (courses
obliquely forward and upward from costal angle to sternum)
Action
ith ribs mobile: Elevates upper ribs
W
(inspiration)
With ribs fixed: Flexes cervical spine
to same side (unilateral); flexes neck
(bilateral)
Elevates ribs (inspiration); supports
intercostal spaces; stabilizes chest wall
1st to 11th
intercostal nn.
Depresses ribs (expiration); supports
intercostal spaces, stabilizes chest wall
Subcostal mm.
Lower margin of lower ribs to inner surface of ribs two to three
ribs below
Adjacent
intercostal nn.
Depresses ribs (expiration)
⑦ Transversus thoracis m.
Sternum and xiphoid process
(inner surface)
2nd to 6th
intercostal nn.
Weakly depresses ribs (expiration)
2nd to 6th ribs (costal
cartilage, inner surface)
Fig. 7.10 Muscles of the thoracic wall
Atlas (C1)
Anterior longitudinal lig.
Posterior
scalene
Middle
scalene
7 Thoracic Wall
Anterior view. The external intercostal muscles
are replaced anteriorly by the external intercostal membrane. The internal intercostal
muscles are replaced posteriorly by the
­internal intercostal membrane.
Axis (C2)
Anterior
scalene
1st rib
Manubrium
External
intercostal
muscles
Radiate
sternocostal ligs.
External
intercostal
membrane
Internal intercostal
muscles
Sternum
External
intercostal
muscles
Costal
cartilage
Anterior longitudinal lig.
Posterior scalene
Fig. 7.11 Transversus thoracis
Middle scalene
Anterior view with thoracic cage
opened to expose posterior surface
of anterior wall. The external and
internal intercostal membranes Manubrium
have been removed.
Anterior scalene
Innermost
intercostal
muscles
Internal
intercostal
muscles
External
intercostal
muscles
Transversus
thoracis
Internal
intercostal
muscles
Xiphoid
process
Costal
cartilage
Subcostal
muscles
Chondro-osseous junction
63
Thorax
Diaphragm
Fig. 7.12 Diaphragm
Clavicle
The diaphragm, which separates the thorax from the abdomen, has two
asymmetric domes and three apertures (for the aorta, vena cava, and
esophagus; see Fig. 7.13C).
Scapula
Diaphragm,
sternal part
(attaching
posterior to
the sternum)
Caval
opening
Central
tendon
Diaphragm,
costal part
Diaphragm,
left dome
Diaphragm,
right dome
Diaphragm,
lumbar part
Xiphoid
process
Diaphragm,
costal part
10th rib
Sternum
12th rib
Lumbocostal
triangle
Transverse
process, L1
Aortic
hiatus
Diaphragm,
lumbar part
Right
crus
Transverse process, L1
B
Posterior view.
Left
crus
A
Anterior view.
Caval
opening
Esophageal
hiatus
Central
tendon
Right
dome
Left dome
Median
arcuate lig.
Diaphragm,
costal part
Right crus
Diaphragm,
lumbar part
Lateral
arcuate lig.
Left crus
Aortic
hiatus
Quadratus
lumborum
C
Coronal section with diaphragm in
intermediate position.
Table 7.3
Origin
Costal part
Medial arcuate
lig.
Transversus
abdominis
Insertion
Innervation
Action
Central
tendon
Phrenic n. (C3–C5,
cervical plexus)
Principal muscle of respiration
(diaphragmatic and thoracic
breathing); aids in compressing
abdominal viscera (abdominal
press)
7th to 12th ribs (inner surface; lower margin of costal
arch)
Lumbar part
Medial part: L1–L3 vertebral bodies, intervertebral disks,
and anterior longitudinal lig. as right and left crura
Sternal part
Xiphoid process (posterior surface)
Lateral parts: lateral and medial arcuate ligs.
64
Psoas
minor
Diaphragm
Muscle
Diaphragm
Psoas
major
Caval
opening
Sternocostal
triangle
Sternum
Diaphragm,
sternal part
Fig. 7.13 Diaphragm in situ
Rectus
abdominis
7 Thoracic Wall
Central
tendon
Diaphragm,
costal part
Median
arcuate lig.
Aortic hiatus
Esophageal
hiatus
External
oblique
Left crus
Right crus
Lumbocostal
(Bochdalek’s)
triangle
Internal
oblique
Transversus
abdominis
Latissimus
dorsi
Quadratus
lumborum
Lateral arcuate
lig.
Psoas
major
Vertebral
Intrinsic
body
back muscles
Medial arcuate lig.
Inferior view.
A
Sternum
Diaphragm,
sternal part
Central
tendon
Caval
opening
Diaphragm,
costal part
Intercostal
muscles
Aortic hiatus
Esophageal
hiatus
T8
Rib
T8
Inferior vena cava
Intrinsic
back muscles
Parietal pleura,
costal part
B
Superior view.
Esophagus
T10
T12
Aorta
C
Diaphragmatic apertures, left lateral view.
65
Thorax
Neurovasculature of the Diaphragm
Fig. 7.14 Neurovasculature of the diaphragm
Anterior view of opened thoracic cage.
Inferior thyroid v.
Left common carotid a.
Left internal jugular v.
Left external jugular v.
Left subclavian a. and v.
Left brachiocephalic v.
Left phrenic n.
Right phrenic n.
Superior vena cava
Internal thoracic a.
Posterior intercostal vv.
Accessory hemiazygous v.
Azygos v.
Pericardiacophrenic a.
Hemiazygos v.
Musculophrenic a.
Superior phrenic aa.
Left phrenic n.
Inferior phrenic aa.
Celiac trunk
Inferior vena cava
C3
Fig. 7.15 Innervation of
the diaphragm
C4
C5
Anterior view. The phrenic nerves lie on the
lateral surfaces of the fibrous pericardium
together with the pericardiacophrenic arteries and veins. Note: The phrenic nerves also
innervate the pericardium.
Anterior scalene
Left phrenic n.
Right phrenic n.
Rib
From parietal pleura,
mediastinal part
Intercostal mm.
Pericardial brs.
From parietal pleura,
diaphragmatic part
Phrenicoabdominal br.
of phrenic n.
Intercostal nn.
Diaphragm
Efferent (somatic
motor) fibers
66
Afferent (somatic
sensory) fibers
Table 7.4
Blood vessels of the diaphragm
Origin
Vein
Drainage
Inferior phrenic aa. (chief blood supply)
Abdominal aorta; occasionally from celiac trunk
Inferior phrenic vv.
Inferior vena cava
Superior phrenic aa.
Thoracic aorta
Superior phrenic vv.
Azygos v. (right side),
hemiazygos v. (left side)
Pericardiacophrenic vv.
Internal thoracic vv. or
brachiocephalic vv.
Musculophrenic vv.
Internal thoracic vv.
Pericardiacophrenic aa.
Internal thoracic aa.
Musculophrenic aa.
7 Thoracic Wall
Artery
Fig. 7.16 Arteries and nerves of the diaphragm
Note: The margins of the diaphragm receive sensory innervation from
the lowest intercostal nerves.
Sympathetic trunk
Spinal cord
Thoracic aorta
Hemiazygos v.
Intercostal n.
Parietal pleura,
costal part
Azygos v.
Parietal pleura,
diaphragmatic part
Left superior
phrenic a.
(from thoracic aorta)
Right superior
phrenic a.
Parietal pleura,
mediastinal part
Inferior vena cava
Esophagus
Phrenic n.,
pericardiacophrenic
a. and v.
Parietal pleura,
costal part
A
Superior view (~T8).
Pericardium
Musculophrenic a.
(from internal
thoracic a.)
Internal thoracic
a. and vv.
Sternum
Diaphragm,
central tendon
Rectus
abdominis
Diaphragm,
costal part
Esophageal
hiatus
Caval
opening
Phrenic n.,
phrenicoabdominal br.
Right phrenic n.
Celiac trunk
Right inferior
phrenic a.
Left inferior
phrenic a.
Right superior
suprarenal a.
Left superior
suprarenal a.
Common
hepatic a.
Splenic a.
External and internal
oblique muscles,
tranversus abdominis
Greater
splanchnic n.
Diaphragm,
lumbar part
B
Inferior view (~T12).
Removed: Parietal peritoneum.
Left
phrenic n.
Left ascending
lumbar v.
Quadratus
lumborum
Psoas
major
Abdominal
aorta
Spinal
cord
Lumbar
vertebra
Intrinsic
back muscles
67
Thorax
Arteries & Veins of the Thoracic Wall
The posterior intercostal arteries anastomose with the anterior
intercostal arteries to supply the structures of the thoracic wall.
The posterior intercostal arteries branch from the thoracic aorta,
with the exception of the 1st and 2nd, which arise from the superior
intercostal artery (a branch of the costocervical trunk).
Fig. 7.17 Arteries of the thoracic wall
Left common
carotid a.
Anterior view.
Table 7.5
Origin
Superior
thoracic a.
Arteries of the
thoracic wall
Thyrocervical
trunk
Vertebral a.
Thoracoacromial a.
Left subclavian a.
Axillary a.
Branch
Internal thoracic a.
Lateral thoracic a.
Axillary a.
Subclavian a.
Thoracoacromial a.
2nd intercostal a.
Posterior intercostal aa.
(1st and 2nd; see Fig. 4.1,
p. 36)
Thoracic aorta
Superior thoracic a.
Thoracic
aorta
Dorsal br.
Thoracodorsal a.
Posterior intercostal aa.
(3rd through 12th)
Posterior
intercostal a.
Collateral br.
Anterior intercostal aa.
Internal
thoracic a.
Lateral
cutaneous br.
Musculophrenic a.
Lateral
thoracic a.
Superior epigastric a.
Medial mammary br.
Internal
thoracic a.
Anterior intercostal a.
Anterior
intercostal aa.
Abdominal aorta
Superior epigastric a.
Musculophrenic a.
2nd and 3rd lumbar aa.
Aortic bifurcation
Fig. 7.18 Branches of the
intercostal arteries
Superior view.
Table 7.6
Sternal brs.
Anterior
cutaneous br.
Dorsal branch of
posterior intercostal a.
Artery
Branches
Supplies
Spinal br.
Spinal br.
Internal
thoracic a.
Posterior
intercostal a.
Anterior
intercostal a.
Lateral
cutaneous br.
Branches of the
intercostal arteries
Dorsal br.
Medial
cutaneous br.
Posterior
intercostal aa.
Thoracic
aorta
Medial
cutaneous br.
Lateral
cutaneous br.
Lateral
cutaneous br.
68
Posterior
thoracic
wall
Collateral br.
Lateral
thoracic
wall
Lateral cutaneous br.*
Anterior
thoracic
wall
Posterior intercostal a.
Anterior
intercostal aa.
Spinal
cord
*The lateral mammary br. from the lateral cutaneous br.
supplies the breast along with the medial mammary br.
from the internal thoracic a.
The intercostal veins drain primarily into the azygos system, but also
into the internal thoracic vein. This blood ultimately returns to the
heart via the superior vena cava. The intercostal veins follow a similar
course to their arterial counterparts. However, the veins of the vertebral
column form an external vertebral venous plexus that traverses the
entire length of the spine (see p. 37).
Anterior and posterior
internal vertebral venous plexus
Right internal
jugular v.
Left brachiocephalic v.
Right
brachiocephalic v.
7 Thoracic Wall
Fig. 7.19 Veins of the thoracic wall
Left subclavian v.
Right
subclavian v.
Posterior
intercostal vv.
Internal
thoracic v.
Superior
vena cava
Anterior
intercostal vv.
Accessory
hemiazygos v.
Internal
thoracic vv.
Azygos v.
Azygos v.
Anterior
external
venous
plexus
Hemiazygos v.
B
Vertebral venous plexus, anterior view.
Posterior
intercostal vv.
Inferior
vena cava
Subcostal v.
(12th intercostal v.)
1st lumbar v.
AAnterior view with
rib cage opened.
Internal jugular v.
External jugular v.
Subclavian v.
Axillary v.
Cephalic v.
Superior vena cava
Azygos v.
Areolar venous plexus
Thoracoepigastric v.
Inferior vena cava
Periumbilical vv.
Common iliac v.
Fig. 7.20 Superficial veins
Anterior view. The thoracoepigastric veins are
a potential superficial collateral venous drainage route in the event of superior or inferior
vena cava obstruction.
External iliac v.
Superficial epigastric v.
Superficial circumflex iliac v.
External pudendal v.
Femoral v.
Great saphenous v.
69
Thorax
Nerves of the Thoracic Wall
Fig. 7.21 Intercostal nerves
Anterior view. The 1st rib has been removed
to reveal the 1st and 2nd intercostal nerves.
1st and 2nd
intercostal nn.
Posterior
ramus
Lateral cutaneous br.
T1
Intercostobrachial nn.
Anterior cutaneous br.
3rd and 4th
intercostal nn.
Anastomosis
with medial
brachial
cutaneous n.
Sternal brs.
Subcostal n.
(12th intercostal n.)
Fig. 7.22 Cutaneous innervation of the thoracic wall
Supraclavicular nn.
Supraclavicular nn.
Medial
cutaneous brs.
Anterior
cutaneous brs.
Spinal nn.,
dorsal rami
Lateral
cutaneous brs.
Intercostal nn.
Lateral
cutaneous brs.
Superior
clunial nn.
Iliohypogastric n.,
lateral cutaneous br.
A
Anterior view.
70
B
Posterior view.
Intercostal nn.,
lateral cutaneous brs.
Superior view. The spinal nerve is formed by the union of posterior
(dorsal) and anterior (ventral) roots. The posterior root contains sensory fibers and the anterior root contains motor fibers. The spinal nerve
and all its subsequent branches are mixed nerves, containing both
motor and sensory fibers. The spinal nerve exits the vertebral canal
via the intervertebral foramen. Its posterior ramus innervates the skin
and intrinsic muscles of the back; its anterior ramus forms the cervical,
brachial, lumbar, and sacral plexuses, and the intercostal nerves. See
p. 38 for more details.
Posterior
root
Sensory
(spinal) ganglion
Fig. 7.24 Arrangement of intercostal
neurovascular bundle
Coronal section, anterior view.
Right lung
8th rib
Visceral pleura
Intercostal
v., a.,
and n.
Anterior
root
Posterior
ramus
Gray ramus
communicans
White ramus
communicans
Anterior
ramus
(intercostal n.)
Sympathetic
ganglion
Meningeal br.
7 Thoracic Wall
Fig. 7.23 Spinal nerve branches
Lateral
cutaneous br.
Parietal pleura,
costal part
Diaphragm
Costal
groove
Endothoracic
fascia
External
intercostal
Liver
Anterior cutaneous br.
Internal
intercostal
Innermost
intercostal
Fig. 7.25 Dermatomes of the thoracic wall
Landmarks: T4 generally includes the nipple; T6 innervates the skin over
the xiphoid.
C3
C5
C3
C4
T2
C4
T2
C5
T4
T6
L1
T 10
L1
A
Anterior view.
B
Posterior view.
71
Thorax
Neurovascular Topography of the Thoracic Wall
Fig. 7.26 Anterior structures
Axillary a. and v.
Anterior view (see Chapter 4
for neurovasculature
of the back).
External jugular v.
Deltoid
Median n.
Ulnar n.
Lateral thoracic
a. and v.
Cephalic v.
Thoracoepigastric v.
Internal thoracic
a. and v.
Anterior
cutaneous brs.
Intercostal a.,
v., and n.
Lateral
cutaneous brs.
Intercostal aa.,
vv., and nn.
Superior epigastric
a. and v.
External
oblique
Internal
oblique
Rectus
abdominis
Clinical box 7.1
Insertion of a chest tube
Abnormal fluid collection in the pleural space (e.g., pleural effusion due to
bronchial carcinoma) may necessitate the insertion of a chest tube. Generally,
the optimal puncture site in a sitting patient is at the level of the 4th or 5th
intercostal space in the mid to anterior axillary line, immediately behind the
lateral edge of the pectoralis major. The drain should always be introduced
at the upper margin of a rib to avoid injuring the intercostal vein, artery, and
nerve. See Clinical box 10.5 on p. 123 for details on collapsed lungs.
Pectoralis
major
Pleural effusion
Parietal pleura
Costal groove
Intercostal
v., a., and n.
Visceral pleura
Endothoracic
fascia
Rib
B
Drainage tube is inserted
perpendicular to chest wall.
Chest tube
Pleural space
Puncture site
Innermost
intercostal
A
Coronal section, anterior view.
72
Internal and
external
intercostal
muscles
DAt the superior margin of the rib,
the tube is passed through the
intercostal muscles and advanced
into the pleural cavity.
C
At ribs, the tube is angled and
advanced parallel to the chest
wall in the subcutaneous plane.
7 Thoracic Wall
Fig. 7.27 Intercostal structures in cross section
Transverse section, anterosuperior view. The relationship of the intercostal vessels in the costal groove, from superior to inferior, is vein,
artery, and nerve (see clinical box, p. 72).
Right superior
phrenic a.
Latissimus
dorsi
External
intercostal
Costal
groove
Intercostal n.,
collateral br.
Intrinsic
back muscles
Intercostal v.,
posterior br.
Spinal cord (with
spinal ganglion)
Internal
intercostal
Intercostal nn.,
anterior rami
Innermost
intercostal
Posterior
intercostal aa.
and vv.
Parietal pleura,
costal part
Azygos v.
Central tendon
of diaphragm
Thoracic aorta
Esophagus
Serratus anterior
Inferior vena cava
Diaphragm
Phrenic n.,
pericardiacophrenic a. and v.
Pericardial sac
Parietal pleura,
diaphragmatic part
Intercostal n.,
lateral cutaneous br.
Musculophrenic a.
(from internal
thoracic a.)
Internal
thoracic a. and vv.
Anterior
perforating br.
Sternum
External oblique
Intercostal n.,
anterior cutaneous br.
73
Thorax
Female Breast
The female breast, a modified sweat gland in the subcutaneous tissue
layer, consists of glandular tissue, fibrous stroma, and fat. The breast
extends from the 2nd to the 6th rib and is loosely attached to the p
­ ec-
toral, axillary, and superficial abdominal fascia by connective tissue. The
breast is additionally supported by suspensory ligaments. An extension
of the breast tissue into the axilla, the axillary tail, is generally present.
Fig. 7.28 Female breast
Fig. 7.29 Mammary ridges
Right breast, anterior view.
Rudimentary mammary glands form in both sexes along the mammary
ridges. Occasionally, these may persist in humans to form accessory
nipples (polythelia), although only thoracic nipples normally remain.
Nipple
Areola
Areolar
glands
Fig. 7.30 Blood supply
to the breast
Axillary a.
and v.
Subclavian
a. and v.
Internal thoracic
a. and v.
Lateral thoracic
a. and v.
Medial
mammary brs.
Perforating brs.
Fig. 7.31 Sensory innervation
of the breast
Lateral
mammary brs.
Mammary brs.
Supraclavicular nn.
Intercostal nn.,
medial mammary brs.
Intercostal nn.,
lateral mammary brs.
74
The glandular tissue is composed of 10 to 20 individual lobes, each with
its own lactiferous duct. The gland ducts open on the elevated nipple at
the center of the pigmented areola. Just proximal to the duct opening is
a dilated portion called the lactiferous sinus. Areolar elevations are the
openings of the areolar glands (sebaceous). The glands and lactiferous
ducts are surrounded by firm, fibrofatty tissue with a rich blood supply.
7 Thoracic Wall
Fig. 7.32 Structures of the breast
Pectoral fascia
Suspensory
(Cooper’s) ligs.
Pectoralis minor
Mammary
lobes
Intercostal
muscles
Nipple
Pectoralis major
Lactiferous
sinus
Intercostal
v., a., and n.
Lactiferous duct
Superficial
thoracic fascia
Interlobular
connective tissue
A
Sagittal section
along midclavicular line.
Lobules
Lactiferous duct
Lactiferous sinus
Acini
Mammary
lobes
B
Duct system and portions of a lobe, sagittal section. In the nonlactating breast (shown here), the lobules contain clusters of rudimentary acini.
Terminal duct
Terminal duct
lobular unit (TDLU)
C
Terminal duct lobular unit (TDLU). The clustered acini composing the
lobule empty into a terminal ductule; these structures are collectively known as the TDLU.
75
Thorax
Lymphatics of the Female Breast
­relationship to the pectoralis minor (Table 7.7). The medial portion of
the breast is drained by the parasternal lymph nodes, which are associated with the internal thoracic vessels.
The lymphatic vessels of the breast (not shown) are divided into three
systems: superficial, subcutaneous, and deep. These drain primarily into the axillary lymph nodes, which are classified based on their
Fig. 7.33 Axillary lymph
nodes
Level II
Level III
Level I
Interpectoral axillary l.n.
Parasternal l.n.
A
Lymphatic drainage of the breast.
See Table 7.7 for explanation of
level I, II, and III.
Supraclavicular l.n.
Axillary a.
Pectoralis major
Subscapular
axillary l.n.
Central
axillary l.n.
Omohyoid,
inferior belly
(cut)
Cervical l.n.
Internal
jugular v.
Brachial v.
Subclavian a.
Biceps brachii
Clavicle
Apical axillary l.n.
Basilic v.
Pectoralis minor
Brachial a.
Interpectoral
axillary l.n.
Pectoralis major
Cubital l.n.
Pectoral axillary l.n.
Axillary
lymphatic
plexus
Brachial l.n.
Supratrochlear l.n.
Lateral thoracic v.
Humeral
axillary l.n.
Latissimus dorsi
B
Anterior view.
Table 7.7
Levels of axillary lymph nodes
Level
Position
Lymph nodes (l.n.)
Pectoral axillary l.n.
I
Lower axillary group
Lateral to pectoralis minor
Subscapular axillary l.n.
Humeral axillary l.n.
76
II
Middle axillary group
Along pectoralis minor
III
Upper infraclavicular group
Medial to pectoralis minor
Central axillary l.n.
Interpectoral axillary l.n.
Apical axillary l.n.
Clinical box 7.2
Stem cells in the intralobular connective tissue give rise to tremendous cell
growth, necessary for duct system proliferation and acini differentiation. This
makes the terminal duct lobular unit (TDLU) the most common site of origin
of malignant breast tumors.
Lobules
7 Thoracic Wall
Breast cancer
Lactiferous duct
Lactiferous sinus
≈ 60%
≈15%
≈10%
Acini
Terminal duct
≈10%
≈ 5%
Terminal duct
lobular unit (TDLU)
A
Terminal duct lobular unit.
B
Origin of malignant tumors by quadrant.
Tumors originating in the breast spread via the lymphatic vessels. The deep
system of lymphatic drainage (level III) is of particular importance, although
the parasternal lymph nodes provide a route by which tumor cells may
spread across the midline. The survival rate in breast cancer correlates most
strongly with the number of lymph nodes involved at the axillary nodal
level. Metastatic involvement is gauged through scintigraphic mapping
with radiolabeled colloids (technetium [Tc] 99m sulfur microcolloid). The
downstream sentinel node is the first to receive lymphatic drainage from
the tumor and is therefore the first to be visualized with radiolabeling.
Once identified, it can then be removed (via sentinel lymphadenectomy)
and histologically examined for tumor cells. This method is 98% accurate in
predicting the level of axillary nodal involvement.
Metastatic involvement
5-year survival rate
Level I
65%
Level II
31%
Level III
~0%
Nipple
Normal mammogram.
C
DMammogram of invasive ductal carcinoma (irregular white areas, arrows). The
large lesion has changed the architecture of the neighboring breast tissue.
77
8
Thoracic Cavity
Thorax
Divisions of the Thoracic Cavity
The thoracic cavity is divided into three large spaces: the mediastinum
(p. 90) and the two pleural (pulmonary) cavities (p. 112).
Fig. 8.1 Thoracic cavity
Coronal section, anterior view.
Table 8.1
Thoracic
inlet
Major structures of the thoracic cavity
Thymus, great vessels, trachea,
esophagus, and thoracic duct
Superior mediastinum
Superior
mediastinum
Right lung in
right pulmonary
cavity
Mediastinum
Left lung in
left pulmonary
cavity
Inferior
mediastinum
Diaphragm
Pulmonary
cavities
Thoracic outlet
Inferior
mediastinum
Anterior
Thymus (especially in children)
Middle
Heart, pericardium, and roots of
great vessels
Posterior
Thoracic aorta, thoracic duct,
esophagus, and azygos venous
system
Right pulmonary cavity
Right lung
Left pulmonary cavity
Left lung
A
Divisions of the thoracic cavity.
Right common
carotid a.
Thyroid gland,
right lobe
Thyroid
cartilage
Internal jugular v.
Left phrenic n.
Recurrent laryngeal n.
Right phrenic n.
Brachial plexus
Anterior scalene
Left vagus n.
Trachea
Left subclavian a. and. v.
Right vagus n.
Internal thoracic
a. and v.
Brachiocephalic
trunk
First rib
Left brachiocephalic v.
Right brachiocephalic v.
Aortic arch
Superior
vena cava
Left vagus n.
Thymus
Left pulmonary a.
Pericardiacophrenic a. and v.,
phrenic n.
Parietal pleura,
mediastinal part
Left lung
Right lung
B
Opened thoracic cavity. Removed: Thoracic wall;
connective tissue of anterior mediastinum.
78
Fibrous
pericardium
Pericardiacophrenic a. and v.,
pericardial branches
Phrenic n.,
pericardial branches
Parietal pleura
(diaphragmatic part)
8 Thoracic Cavity
Fig. 8.2 Divisions of the mediastinum
Esophagus
(cervical part)
Cervical part
Thoracic inlet
Thoracic part
Esophagus
(thoracic part)
Trachea
Sternum
Anterior
mediastinum
Superior
mediastinum
Sternum
Anterior
mediastinum
Posterior
mediastinum
Middle
mediastinum
Posterior
mediastinum
Esophagus
Right lung
Left lung
Middle
mediastinum
Diaphragm
Thoracic
vertebra
Descending
aorta
Transverse section, inferior view.
B
Midsagittal section, lateral view.
A
Fig. 8.3 Transverse sections of the thorax
Computed tomography (CT) scan of thorax, inferior view.
Superior vena cava
Right and left
main bronchi
A
Superior mediastinum.
Ascending aorta
Esophagus
Inferior vena cava
Esophagus
Azygos v.
Descending
aorta
Descending
aorta
B
Inferior mediastinum.
79
Thorax
Arteries of the Thoracic Cavity
The arch of the aorta has three major branches: the brachiocephalic
trunk, left common carotid artery, and left subclavian artery. After the
aortic arch, the aorta begins its descent, becoming the thoracic aorta
at the level of the sternal angle and the abdominal aorta once it passes
through the aortic hiatus in the diaphragm.
Fig. 8.4 Thoracic aorta
Thyroid cartilage
Right common carotid a.
Anterior scalene
Middle scalene
Left common carotid a.
Trachea
Thyrocervical trunk
Right vertebral a.
Right subclavian a.
Internal thoracic a.
Left subclavian a.
Esophagus
Aortic arch
1st rib
Brachiocephalic trunk
Ascending aorta
Bronchial a.
Right main bronchus
Left main bronchus
Esophageal branch
Posterior intercostal aa.
Thoracic aorta
Diaphragm
Inferior phrenic a.
Aortic hiatus
Celiac trunk
Abdominal aorta
Lumbar a.
A
Thoracic aorta in situ, anterior view. Removed: Heart, lungs, portions of diaphragm.
80
Esophagus
Left common
carotid a.
Brachiocephalic
trunk
Ascending
aorta
Left main
bronchus
Pulmonary
trunk
Left
subclavian a.
Aortic arch
Table 8.2
The thoracic organs are supplied by direct branches from the thoracic aorta, as well as indirect branches from
the subclavian arteries.
Part of aorta
Ascending
aorta
Branches
Region supplied
Right and left coronary aa.
Heart
Bronchi, trachea, esophagus
Right subclavian a.
Brachiocephalic
trunk
Left
pulmonary a.
See left subclavian a.
Right common carotid a.
Left common carotid a.
Descending
aorta
B
Parts of the aorta, left lateral view. Note:
The aortic arch begins and ends at the
level of the sternal angle (see p. 58).
Branches of the thoracic aorta
8 Thoracic Cavity
Trachea
Head and neck
Vertebral a.
rch of
A
aorta
Anterior intercostal aa.
Anterior chest wall
Thymic brs.
Thymus
Mediastinal brs.
Posterior mediastinum
Pericardiacophrenic a.
Pericardium, diaphragm
Thyrocervical trunk
Inferior thyroid a.
Esophagus, trachea, thyroid
gland
Costocervical trunk
Superior intercostal a.
Chest wall
Internal thoracic a.
Left subclavian a.
Descending
aorta
Visceral brs.
Parietal brs.
Bronchi, trachea, esophagus
Posterior intercostal aa.
Posterior chest wall
Superior phrenic aa.
Diaphragm
Clinical box 8.1
Aortic dissection
A tear in the inner wall (intima) of the aorta allows blood to separate the
layers of the aortic wall, creating a “false lumen” and potentially resulting in
life-threatening aortic rupture. Symptoms are dyspnea (shortness of breath)
and sudden onset of excruciating pain. Acute aortic dissections occur most
often in the ascending aorta and generally require surgery. More distal
aortic dissections may be treated conservatively, provided there are no
complications (e.g., obstruction of blood supply to the organs, in which case
a stent may be inserted to restore perfusion). Aortic dissections occurring at
the base of a coronary artery may cause myocardial infarction.
“False lumen”
Ascending
aorta
Intima
“False lumen”
Descending
aorta
A
Aortic dissection. Parts of the intima are still attached to the connective
tissue in the wall of the aorta (arrow).
B The flow in the coronary arteries is intact (arrow).
81
Thorax
Veins of the Thoracic Cavity
The superior vena cava is formed by the union of the two brachio­
cephalic veins at the level of the T2–T3 junction. It receives blood
drained by the azygos system (the inferior vena cava has no tributaries
in the thorax).
Fig. 8.5 Superior vena cava and azygos system
Left internal jugular v.
Right supreme intercostal v.
Anterior scalene
Middle scalene
Right subclavian v.
1st rib
Right internal thoracic v.
Left external jugular v.
Left subclavian v.
Inferior thyroid v.
Left brachiocephalic v.
Right brachiocephalic v.
Azygos v.
Superior vena cava
Accessory hemiazygos v.
Posterior intercostal vv.
Hemiazygos v.
Diaphragm, central tendon
Caval opening
Diaphragm, costal part
Esophageal hiatus
Right ascending lumbar v.
Left ascending lumbar v.
Aortic hiatus
Inferior vena cava
Lumbar vv.
A
Veins of the thoracic cavity (viscera removed), anterior view of
opened thorax (posterior thoracic wall).
82
Thoracic tributaries of the superior vena cava
Table 8.3
Major vein
Superior
vena cava
Right
subclavian
v.
Left
pulmonary
vv.
Right
brachiocephalic v.
Brachiocephalic vv.
Inferior thyroid v.
Esophagus, trachea,
thyroid gland
External jugular vv.
Subclavian vv.
Head, neck,
upper limb
Supreme intercostal vv.
Pericardial vv.
Left superior intercostal v.
Azygos system
(left side: accessory
hemiazygos v.;
right side: azygos v.)
B
Projection of venae cavae onto chest,
anterior view.
Region drained
Internal jugular vv.
Inferior
vena cava
Right
pulmonary
vv.
Tributaries
8 Thoracic Cavity
Left
brachiocephalic v.
Right
internal
jugular v.
Trachea, bronchi,
esophagus
Visceral brs.
Posterior intercostal vv.
Parietal brs.
Superior phrenic vv.
Right superior intercostal v.
Internal thoracic v.
Inner chest wall and
diaphragm
Thymic vv.
Thymus
Mediastinal tributaries
Posterior
mediastinum
Anterior intercostal vv.
Anterior chest wall
Pericardiacophrenic v.
Pericardium
Musculophrenic v.
Diaphragm
Note: Structures of the superior mediastinum may also drain directly to the brachiocephalic veins
via the tracheal, esophageal, and mediastinal veins.
Fig. 8.6 Azygos system
Anterior view.
Right internal
jugular v.
Inferior thyroid v.
Left brachiocephalic v.
Right subclavian v.
Superior vena cava
Azygos v.
Accessory
hemiazygos v.
Posterior intercostal vv.
Hemiazygos v.
Hepatic vv.
Diaphragm
Left renal v.
Right testicular/
ovarian v.*
Lumbar vv.
Left ascending
lumbar v.
Right ascending
lumbar v.
Left common
iliac v.
Inferior vena cava
*The left testicular/ovarian vein drains to the left renal vein.
83
Thorax
Lymphatics of the Thoracic Cavity
The body’s chief lymph vessel is the thoracic duct. Beginning in the
abdomen at the level of L1 at the cisterna chyli, the thoracic duct
empties into the junction of the left internal jugular and subclavian
veins. The right lymphatic duct drains to the right junction of the
internal jugular and subclavian veins.
Fig. 8.7 Lymphatic trunks in the thorax
Anterior view of opened thorax.
Common carotid a.
Internal jugular v.
Jugular trunk
Subclavian a.
Jugular trunk
Thoracic duct
Right lymphatic duct
Subclavian trunk
Right subclavian v.
Brachiocephalic trunk
Right brachiocephalic v.
Superior vena cava
Bronchomediastinal
trunk
Subclavian trunk
Left subclavian v.
Left brachiocephalic v.
Bronchomediastinal
trunk
Ascending aorta
Thoracic aorta
Accessory
hemiazygos v.
Thoracic duct
Diaphragm
Intercostal
lymphatics
Azygos v.
Hemiazygos v.
Aortic hiatus
Celiac trunk
Abdominal aorta
Cisterna chyli
Left lumbar trunk
Right lumbar trunk
84
Fig. 8.8 Lymphatic drainage
pattern
Fig. 8.9 Lymphatic pathways in
the thorax
Right jugular
trunk
Right lymphatic
duct
Thoracic duct
8 Thoracic Cavity
Head and neck
Left jugular
trunk
Thoracic
duct
Left internal
jugular v.
Right lymphatic
duct
Right subclavian
trunk
Left subclavian
trunk
Left subclavian v.
Left bronchomediastinal trunk
Right bronchomediastinal trunk
Anterior mediastinum
Paravertebral I.n.
Posterior thoracic wall
Anterior intercostal
spaces
Anterior thoracic
wall
Mammary gland
Parasternal I.n.
Posterior intercostal spaces
Paramammary I.n.
Superior mediastinum
Brachiocephalic I.n.
Pre-pericardial I.n.
Lateral pericardial I.n.
Paraesophageal I.n.
Paratracheal I.n.
Tracheobronchial I.n.
Bronchopulmonary I.n.
Intrapulmonary I.n.
Superior phrenic I.n.
Diaphragm
Cisterna chyli
Parasternal l.n.
Abdomen, pelvis, and lower limb
Tracheobronchial l.n.
Lymphatics in
trunk wall
Bronchopulmonary l.n.
Intrapulmonary l.n.
Intercostal l.n.
Paraesophageal l.n.
Paratracheal l.n.
Fig. 8.10 Thoracic lymph nodes
Transverse section at the level of the tracheal
bifurcation (T4–T5), superior view. The thoracic lymph nodes can be divided into three
broad groups: nodes of the thoracic wall
(pink), pulmonary nodes (blue), and mediastinal nodes (green). For details of lymphatics
of the mediastinum, see pp. 110–111.
85
Thorax
Nerves of the Thoracic Cavity
Thoracic innervation is mostly autonomic, arising from the para­
vertebral sympathetic trunks and parasympathetic vagus nerves.
There are two exceptions: the phrenic nerves innervate the pericardium
and diaphragm (p. 66) and the intercostal nerves innervate the thoracic
wall (p. 70).
Left vagus n.
Right vagus n.
Fig. 8.11 Nerves in the thorax
Anterior view of opened thorax.
Sympathetic trunk,
thoracic ganglion
Right
phrenic n.
Left phrenic n.
Posterior
intercostal nn.
A
Thoracic innervation.
Trachea
Esophagus,
cervical part
Common carotid a.
Sympathetic trunk,
middle cervical ganglion
Scalene mm.
Right subclavian a.
Brachial plexus
Right vagus n.
Left subclavian a.
Right recurrent laryngeal n.
1st rib
Brachiocephalic trunk
Left vagus n.
Left recurrent laryngeal n.
Posterior intercostal a.
Aortic arch
Intercostal n.
Esophagus, thoracic part
Thoracic aorta
Sympathetic trunk
Anterior esophageal plexus
Sympathetic trunk
Innermost intercostals
Greater splanchnic n.
Diaphragm
Anterior
vagus br.
B
Nerves of the thorax in situ. Lungs, pericardial sac, heart and costal
pleura removed. Note: The recurrent laryngeal nerves have been
slightly anteriorly retracted; normally, they occupy the groove
86
Stomach
between the trachea and the esopha­gus, making them vulnerable
during thyroid gland surgery.
The autonomic nervous system innervates smooth muscle, cardiac
muscle, and glands. It is subdivided into the sympathetic (red) and
parasympathetic (blue) nervous systems, which together regulate
blood flow, secretions, and organ function.
Sympathetic
nervous system
Parasympathetic
nervous system
Superior cervical ganglion
Middle cervical ganglion
Stellate ganglion
T1
Vagus n. (CN X)
T2
T3
Superior laryngeal n.
Cervical
cardiac nn.
T4
8 Thoracic Cavity
Fig. 8.12 Sympathetic and parasympathetic nervous systems in the thorax
Larynx
T5
T6
T7
Pharyngeal plexus
T8
T9
External carotid
plexus
T10
T11
Internal carotid
plexus
T12
Recurrent
laryngeal n.
L1
Common carotid plexus
L2
Esophageal plexus
Sympathetic trunk
Vertebral plexus
Greater and lesser
splanchnic n.
Subclavian plexus
Thoracic aortic plexus
Pulmonary plexus
Pulmonary plexus
Cardiac plexus
Cardiac brs.
To abdomen
Table 8.4
Peripheral sympathetic nervous system
Origin of preganglionic fibers*
Ganglion
cells
Course of postganglionic fibers
Follow intercostal nn.
Spinal cord
Sympathetic
trunk
Vagal trunks
Sympathetic preganglionic fibers
Sympathetic postganglionic fibers
Parasympathetic preganglionic fibers
Target
Table 8.5
Origin of preganglionic fibers
Blood vessels
and glands in
chest wall
Accompany
intrathoracic aa.
Visceral
targets
Gather in greater and
lesser splanchnic nn.
Abdomen
*The axons of preganglionic neurons exit the spinal cord via the anterior roots
and synapse with postganglionic neurons in the sympathetic ganglia.
Brainstem
Peripheral parasympathetic nervous system
Course of preganglionic
motor axons*
Vagus n.
(CN X)
Target
Cardiac brs.
Cardiac plexus
Esophageal brs.
Esophageal plexus
Tracheal brs.
Trachea
Bronchial brs.
Pulmonary plexus
(bronchi, pulmonary
vessels)
*The ganglion cells of the parasympathetic nervous system are scattered
in microscopic groups in their target organs. The vagus n. thus carries the
preganglionic motor axons to these targets.
CN = cranial n.
87
9
Mediastinum
Thorax
Mediastinum: Overview
The mediastinum is the space in the thorax between the pleural sacs of
the lungs. It is divided into two parts: superior and inferior. The inferior
Fig. 9.1 Divisions of the mediastinum
Table 9.1
mediastinum is further divided into anterior, middle, and posterior
portions.
Contents of the mediastinum
● Superior
mediastinum
Esophagus
(cervical part)
Cervical
part
Thoracic
part
Thoracic inlet
Esophagus,
thoracic part
Posterior
mediastinum
Diaphragm
A
Schematic.
Esophageal inlet
Esophagus, cervical part
● Middle
• Thymus
• Trachea
• Esophagus
• Esophagus
• Smaller vessels
• Ascending aorta
• Pulmonary trunk
and brs.
• Pericardiacophrenic
aa.
• Thoracic aorta
and brs.
Arteries
• Aortic arch
• Brachiocephalic
trunk
• Left common
carotid a.
• Left subclavian a.
Veins
and
lymph
vessels
• Superior vena
cava
•B
rachiocephalic
vv.
• Thoracic duct
and right
lymphatic duct
• Smaller vessels,
lymphatics,
and l.n.
• Superior vena cava
• Azygos v.
• Pulmonary vv.
• Pericardiacophrenic
vv.
• Azygos v.
• Accessory
hemiazygos
and
hemiazygos
vv.
•T
horacic duct
• None
• Phrenic nn.
• Vagus nn.
Nerves
• Vagus nn.
• Left recurrent
laryngeal n.
• Cardiac nn.
• Phrenic nn.
Thyroid cartilage
Trachea
Pretracheal layer
Brachiocephalic l. n.
Azygos v.
Left main bronchus, origin
● Posterior
• Heart
• Pericardium
Trachea
Anterior
mediastinum
Middle
mediastinum
● Anterior
• Thymus,
inferior aspects
(especially in
children)
Organs
Superior
mediastinum
Sternum
Inferior mediastinum
Investing layer
Deep
cervical
fascia
Left brachiocephalic v.
Manubrium
Tracheobronchial l. n.
Right pulmonary a.
Esophagus, thoracic part
Left atrium
Ascending aorta
Thymus (retrosternal fat pad)
Aortic valve
Sternum
Pericardial cavity
Superior phrenic l. n.
Diaphragm
Liver
B
Midsagittal section, right lateral view.
88
Site of attachment between
liver and diaphragm (bare area)
Xiphoid process
Thyroid gland,
right lobe
Fig. 9.2 Contents of the mediastinum
Thyroid
cartilage
Anterior scalene
Vagus n. (CN X)
Left recurrent laryngeal n.
Internal thoracic a.
and v.
Inferior
thyroid v.
Thymus
A
Anterior view. The thymus extends into the anterior
division of the inferior mediastinum and grows
throughout childhood. At puberty, high levels of circulating sex hormones cause the thymus to atrophy
leaving indistinguishable pieces embedded in the
fat that now occupies the anterior mediastinum.
9 Mediastinum
Trachea
Left common carotid a.
Phrenic n.
Left vagus n.
Aorta
Superior
vena cava
Pericardiacophrenic
a. and v.,
phrenic n.
Left recurrent
laryngeal n.
Left pulmonary a.
Brachial plexus
Left internal jugular v.
Parietal pleura,
mediastinal
part
Parietal pleura,
diaphragmatic
part
Left subclavian
a. and v.
Left brachiocephalic v.
Parietal
pleura,
cervical part
Aortic arch
Ligamentum
arteriosum
Left pulmonary a.
Superior and
inferior lobar
bronchi
Left pleural cavity
Superior
vena cava
Diaphragm
Attachment between
Fibrous
fibrous pericardium and
pericardium
central tendon of the diaphragm
Right
pulmonary vv.
Pulmonary
trunk
Thoracic
aorta
Parietal pleura,
mediastinal part
Right pleural
cavity
Inferior pharyngeal
constrictor
Left common carotid a.
Left internal jugular v.
Pericardiacophrenic Caval
Esophagus,
Fibrous
a. and v., phrenic n. opening thoracic part pericardium
Left subclavian a. and v.
Aortic arch
Parietal pleura,
diaphragmatic
part
Thyroid gland,
right lobe
Esophagus,
cervical part
Superior vena cava
Trachea
Azygos v.
Right main bronchus
Left pulmonary a.
Fibrous pericardium,
left atrium
Left pulmonary vv.
B
Anterior view with lungs, heart, pericardium,
and thymus removed.
Right pulmonary a.
Esophagus, thoracic part
Right pulmonary vv.
Thoracic aorta
Fibrous pericardium,
left ventricle
Esophageal hiatus
Diaphragm
Fibrous pericardium,
right atrium
Inferior vena cava
(in caval opening)
Posterior
intercostal aa.
C
Posterior view.
89
Thorax
Mediastinum: Structures
Fig. 9.3 Mediastinum
Clavicle
1st rib
White and gray rami
communicantes
Intercostal v., a., and n.
Brachiocephalic l.n.
Right vagus n.
Azygos v.
Sympathetic trunk,
thoracic ganglion
Superior lobar
bronchus
Right pulmonary a.
Common trunk of
middle and inferior
lobar bronchi
Esophagus
Greater
splanchnic n.
Brachial plexus
Right subclavian a. and v.
Brachiocephalic trunk
Right brachiocephalic v.
Right recurrent laryngeal n.
Left brachiocephalic v.
Trachea
Superior vena cava
Right phrenic n.
Mediastinal pleura
Thymus
(retrosternal fat pad)
Fibrous
pericardium
Right pulmonary vv.
Phrenic n.,
pericardiacophrenic
a. and v.
Parietal pleura,
costal part
Posterior intercostal v.
and a., intercostal n.
Intercostal mm.
A
Right lateral view, parasagittal section. Note the many structures
passing between the superior and inferior (middle and posterior)
mediastinum.
90
Diaphragm
(covered by
parietal pleura,
diaphragmatic
part)
9 Mediastinum
Clavicle
1st rib
Brachial plexus
Left subclavian
a. and v.
Esophagus
Left superior
intercostal v.
Left vagus n.
Ligamentum
arteriosum
Left phrenic n.
Left pulmonary a.
Left pulmonary vv.
Parietal pleura,
mediastinal part
Lateral
pericardial l.n.
Left vagus n.
Phrenic n.,
pericardiacophrenic a. and v.
Intercostal v.,
a., and n.
Thoracic duct
Aortic arch
Left recurrent
laryngeal n.
Sympathetic trunk
Accessory
hemiazygos v.
Rami communicantes
Left main bronchus
Thoracic aorta
(descending aorta)
Splanchnic nn.
Parietal pleura,
costal part
Hemiazygos v.
Greater splanchnic n.
Superior
phrenic l.n.
Diaphragm (covered
by parietal pleura,
diaphragmatic part)
Intercostal mm.
Posterior intercostal v.
and a., intercostal n.
B
Left lateral view, parasagittal section. Removed: Left lung and parietal
pleura. Revealed: Posterior mediastinal structures.
91
Thorax
Heart: Functions & Relations
The heart pumps the blood: unoxygenated blood to the lungs and
oxygenated blood throughout the body. It is located posterior to the
sternum in the middle portion of the mediastinum in the pericardial
cavity, located between the right and left pleural cavities containing the
lungs. The apex of the cone-shaped heart points anteriorly and to the
left in the thoracic cavity.
Fig. 9.4 Circulation
Fig. 9.5 Topographical relations of
the heart
Oxygenated blood is shown in red;
deoxygenated blood in blue. See p. 104
for prenatal circulation.
Right common
carotid a.
Upper body
circulation
Left internal
jugular v.
Right brachiocephalic v.
Left subclavian
a. and v.
Ascending
aorta
Superior
vena cava
Pulmonary
trunk
Diaphragm
Cardiac apex
Pulmonary
circulation
Pulmonary v.
Pulmonary a.
Superior vena cava
Ascending aorta
Right atrium
Left atrium
Aorta
A
Projection of the heart and great vessels onto chest,
anterior view.
Left ventricle
Right ventricle
Hepatic vv.
Portal v.
Inferior
vena cava
Portal
circulation
Trachea
Brachiocephalic
trunk
Sternum,
manubrium
Left common
carotid a.
Left subclavian a.
Superior
vena cava
Left main
bronchus
2nd rib
Lower body
circulation
Aortic arch
Pulmonary
trunk
Left
pulmonary
vv.
Sternum,
body
Thoracic
aorta
Esophagus
Pericardial
sac
Diaphragm
Abdominal
aorta
B
Left lateral view. Removed: Left thoracic wall and left lung.
92
Stomach
Fig. 9.6 Heart in situ
Left lung
Superior
vena cava
Serous
pericardium,
parietal layer
Fibrous
pericardium
(= external
layer)
Parietal pleura,
mediastinal
part
9 Mediastinum
Aortic arch
Cardiac surface
Serous
pericardium,
visceral layer
(epicardium)
A
Anterior view of the opened thorax with the thymus
removed and flaps of the anterior layer of the pericardial
sac reflected to reveal the heart.
Right brachiocephalic v.
Diaphragm
Brachiocephalic trunk
Right phrenic n.
Left brachiocephalic v.
Left vagus n.
Right lung
Aortic arch
Ligamentum
arteriosum
Superior
vena cava
Left pulmonary a.
Ascending
aorta
Left phrenic n.
Pulmonary
trunk
Parietal pleura,
mediastinal part
Left auricle
Right auricle
Anterior
interventricular a. (LAD)
Left
ventricle
Cardiac
apex
Diaphragm
Fibrous
pericardium
Right
ventricle
Stomach
B
Anterior view of the opened thorax with thymus and
anterior pericardium removed to reveal the heart.
93
Thorax
Pericardium
Fig. 9.7 Posterior pericardial cavity
Anterior view of opened thorax with the anterior pericardium
removed. The heart has been partially elevated to reveal the
posterior pericardial cavity and the oblique pericardial sinus.
Left vagus n.
Superior
vena cava
Pericardiacophrenic a.
and v., left phrenic n.
Ascending
aorta
Pulmonary
trunk
Left auricle
Left pulmonary vv.
Heart,
diaphragmatic
surface
Oblique pericardial
sinus
Right pulmonary v.
Coronary
sinus
Inferior
vena cava
Fig. 9.8 Posterior pericardium
Anterior view of the opened thorax with the anterior pericardium and
heart removed to reveal the posterior pericardium and the oblique
pericardial sinus. The transverse pericardial sinus is the passage
between the reflections of the serous layer of the pericardium around
the arterial and venous great vessels of the heart.
Left recurrent
laryngeal n.
Ligamentum
arteriosum
Left vagus n.
Pulmonary trunk
Ascending aorta
Left phrenic n.
Transverse
pericardial sinus
Left pulmonary vv.
Superior vena cava
Right pulmonary vv.
Inferior vena cava
Parietal pleura,
mediastinal part
Oblique pericardial
sinus
Serous pericardium,
parietal layer
Fibrous pericardium
Sternum
94
Attachment of
fibrous pericardium
to central tendon of
diaphragm
Fig. 9.9 Posterior relations of the heart
Left vagus n.
Superior vena cava
Left phrenic n.
Ascending aorta
Left pulmonary a.
Cut edge of fibrous pericardium
surrounding origin of a.
Parietal pleura,
mediastinal part
Left pulmonary vv.
Cut edge of fibrous
pericardium surrounding
termination of vv.
Posterior vagal trunk
Anterior esophageal plexus
Esophagus
Anterior vagal trunk
Inferior vena cava
Sternum
Fig. 9.10 Pericardium, pericardial cavity,
and transverse pericardial sinus
Sagittal section through the mediastinum. The fibrous
pericardium is attached to the central tendon of the diaphragm and is continuous superiorly with the outer layer
of the great vessels. The parietal layer of serous pericardium lines the inner surface of the fibrous pericardium
and the visceral layer adheres to the heart. The pericardial
cavity, the space between the parietal and visceral layers
of serous pericardium around the heart, is filled with a
thin layer of serous fluid that allows for frictionless movement. Where the parietal and visceral layers of serous
pericardium reach and reflect around the great vessels,
they are continuous with one another. The passage
between the arterial and venous reflections of the serous
pericardium is the transverse pericardial sinus.
9 Mediastinum
Anterior view of the opened
thorax with the anterior pericardium and heart removed
and a window cut in the posterior pericardium to reveal the
structures immediately posterior to the heart. This shows
the close relationship of the
esophagus to the heart, which
is used in the transesophageal
sonogram to assess the left
atrium of the heart.
Attachment of fibrous
pericardium to central
tendon of diaphragm
Trachea
Esophagus
Left brachiocephalic v.
Ascending aorta
Right
pulmonary a.
Transverse
pericardial
sinus
Pericardial cavity
Aortic valve
Left atrium
Parietal
layer
Visceral
layer
Serous
pericardium
Attachment
of fibrous
pericardium to
central tendon
of diaphragm
Superior
phrenic l.n.
Attachment of liver (bare area)
to diaphragm
Clinical box 9.1
Cardiac Tamponade
Rapid increases of fluid or blood within the pericardial sac inhibits full expansion
of the heart, reducing cardiac blood return, thus decreasing cardiac output. This
condition, cardiac tamponade (compression), is potentially fatal, unless relieved.
The fluid or blood must first be removed to restore cardiac function and then the
cause of the fluid or blood accumulation corrected.
95
Thorax
Heart: Surfaces & Chambers
Note the reflection of visceral serous pericardium to become parietal
serous pericardium.
Aortic arch
Ligamentum arteriosum
Brachiocephalic trunk
Fig. 9.11 Surfaces of the heart
The heart has three surfaces: anterior
(sternocostal), posterior (base), and inferior
(diaphragmatic).
Left pulmonary a.
Right
pulmonary a.
Left pulmonary vv.
Superior
vena cava
Pulmonary
trunk
Ascending
aorta
Right
auricle
Right
atrium
Coronary (right
atrioventricular)
sulcus
Left
auricle
Fibrous pericardium
(cut edge)
Anterior interventricular
sulcus
Left
ventricle
Right
ventricle
Left common
carotid a.
Left subclavian a.
Left subclavian a.
Left common
carotid a.
Inferior
vena cava
Brachiocephalic
trunk
Anterior (sternocostal) surface.
A
Aortic arch
Left pulmonary a.
Cardiac apex
Superior vena cava
Left pulmonary vv.
Right pulmonary a.
Left auricle
Right pulmonary vv.
Left atrium
Right atrium
Left
ventricle
Visceral layer of
serous pericardium
(reflected edge)
Coronary
sinus
Posterior surface (base).
B
Inferior vena cava
Aortic arch
Left pulmonary a.
Left
pulmonary vv.
Superior vena cava
Right pulmonary a.
Right
pulmonary vv.
Left atrium
Right
atrium
Coronary
sinus
Inferior
vena cava
Crux of
heart
Left
ventricle
Cardiac apex
Inferior (diaphragmatic) surface.
C
96
Right
ventricle
Posterior
interventricular
sulcus
Aortic arch
Fig. 9.12 Chambers of the heart
Ligamentum
arteriosum
9 Mediastinum
Pulmonary
trunk
Left pulmonary vv.
Right pulmonary a.
Superior vena cava
Valve of pulmonary
trunk, cusps
Conus arteriosus
(infundibulum)
Supraventricular
crest
Septal papillary m.
Right atrium
Left ventricle
Coronary sulcus
Right atrioventricular valve,
anterior cusp
Interventricular
septum
Trabeculae
carneae
Inferior vena cava
Tendinous
cords
Anterior
papillary m.
Cardiac apex
Posterior
papillary m.
A
Right ventricle, anterior view. Note the
supraventricular crest, which marks the
adult boundary between the embryonic
ventricle and the bulbus cordis (now conus
arteriosus).
Septomarginal
trabecula
(moderator band)
Ascending
aorta
Superior
vena cava
Pulmonary
trunk
Right pulmonary a.
Right
auricle
Left atrium
Terminal crest
Right
pulmonary vv.
Pectinate mm.
Right ventricle
Interatrial
septum
Right atrioventricular orifice with
atrioventricular
valve
Limbus of
oval fossa
Oval fossa
Inferior
vena cava
Valve of
inferior vena cava
Valve of
coronary sinus
B
Right atrium, right lateral view.
Left pulmonary a.
Aortic
arch
Pulmonary trunk
Right pulmonary a.
Left auricle
Pectinate mm.
Left superior pulmonary v.
Anterior
papillary m.
Valve of oval fossa
Left atrium
Trabeculae carneae
of interventricular
septum
Interatrial septum
Tendinous
cords
Cardiac
apex
Inferior
vena cava
Posterior
papillary m.
Left atrioventricular valve, cusp
C
Left atrium and ventricle, left lateral view.
Note the irregular trabeculae carneae
characteristic of the ventricular wall.
97
Thorax
Heart: Valves
The cardiac valves are divided into two types: semilunar and atrio­
ventricular. The two semilunar valves (aortic and pulmonary) located
at the base of the two great arteries of the heart regulate passage of
Pulmonary
valve
Right cusp
Anterior cusp
blood from the ventricles to the aorta and pulmonary trunk. The two
atrioventricular valves (left and right) lie at the interface between the
atria and ventricles.
Fig. 9.13 Cardiac valves
Left cusp
Posterior cusp
Left cusp
Anterior interventricular a. (LAD)
Right coronary a.
Left coronary a.
Anterior
cusp
Circumflex a.
Left atrioventricular
(bicuspid or
mitral) valve
Plane of cardiac valves, superior view.
Removed: Atria and great arteries.
Aortic valve
Right cusp
Anterior
cusp
Right atrioventricular
(tricuspid)
valve
Septal
cusp
Posterior
cusp
Posterior
cusp
Coronary sinus
AVentricular diastole (relaxation of the
ventricles). Closed: Semilunar valves.
Open: Atrioventricular valves.
Pulmonary
valve
Right cusp
Anterior cusp
Left cusp
Anterior interventricular a. (LAD)
Right coronary a.
Left coronary a.
Anterior
cusp
Circumflex a.
Fibrous ring
of pulmonary valve
Left fibrous
trigone
Left atrioventricular
valve
Anterior
cusp
Septal
cusp
Posterior
cusp
Right atrioventricular
valve
Posterior
cusp
Tendon of
conus
Fibrous ring
of aortic valve
Aortic valve
Right cusp
Posterior cusp
Left cusp
Coronary sinus
Ventricular systole (contraction of the ventricles).
B
Closed: Atrioventricular valves. Open: Semilunar valves.
Right fibrous
trigone
Table 9.2
Left fibrous
anulus
Opening for the
bundle of His
Right fibrous
anulus
Cardiac skeleton, superior view. The cardiac skeleton is formed by
C
dense fibrous connective tissue. The fibrous anuli (rings) and intervening trigones separate the atria from the ventricles. This provides
mechanical ­stability, electrical insulation (see p. 102 for cardiac
conduction system), and an attachment point for the cardiac muscles
and valve cusps.
98
Position and auscultation sites of cardiac valves
Valve
Anatomical projection
Auscultation site
Aortic valve
Left sternal border (at level
of 3rd rib)
Right 2nd intercostal
space (at sternal margin)
Pulmonary valve
Left sternal border (at level
of 3rd costal cartilage)
Left 2nd intercostal
space (at sternal margin)
Left atrioventricular
valve
Left 4th/5th costal
cartilage
Left 5th intercostal space
(at midclavicular line) or
cardiac apex
Right atrioventricular
valve
Sternum (at level of 5th
costal cartilage)
Left 5th intercostal
space (at sternal margin)
Fig. 9.14 Semilunar valves
Fig. 9.15 Atrioventricular valves
Valves have been longitudinally sectioned and opened.
Nodule
Commissural
cusp
Lunule
Opening
of right
coronary a.
Opening
of left
coronary a.
Aortic
sinus
Left
atrium
9 Mediastinum
Ascending aorta
Anterior view during ventricular systole.
Posterior
cusp
Anterior cusp
Left cusp
Right
cusp
Interatrial
septum
Interventricular
septum
Posterior cusp
Tendinous
cords
Membranous
part
Posterior
papillary m.
Muscular
part
Anterior
papillary m.
Posterior
papillary m.
A
Aortic valve.
Cardiac apex
A
Left atrioventricular valve.
Nodule
Pulmonary trunk
Opening
of right
pulmonary a.
Right cusp
Anterior
cusp
Anterior cusp
Lunule
Left cusp
Trabeculae
carnae
B
Pulmonary valve.
Posterior
cusp
Tendinous
cords
Posterior
papillary m.
Septal cusp
Septal
papillary m.
Interventricular
septum
Anterior
papillary m.
Septomarginal
trabecula
B
Right atrioventricular valve.
Clinical box 9.2
Auscultation of the cardiac valves
Heart sounds, produced by closure of the
semilunar and atrioventricular valves, are
carried by the blood flowing through the valve.
The resulting sounds are therefore best heard
“downstream,” at defined auscultation sites
(dark circles on diagram). Valvular heart disease
causes turbulent blood flow through the valve;
this produces a murmur that may be detected
in the region of ascultation.
Aortic valve
Right atrioventricular valve
Pulmonary valve
Left atrioventricular valve
99
Thorax
Arteries & Veins of the Heart
Fig. 9.16 Coronary arteries and cardiac
veins
Pulmonary
valve
Superior
vena cava
Superior left
pulmonary v.
Atrial brs.
Ascending aorta
with aortic sinus
Left auricle (atrial appendage)
Left coronary a.
Br. to sinoatrial node
Circumflex br.
Right auricle
(atrial appendage)
Left marginal a. and v.
Right coronary a.
Great cardiac v.
Conus br.
Anterior interventricular br.
(left anterior
descending)
Atrial br.
Small cardiac v.
Right marginal
a. and v.
Lateral br.
Anterior vv. of
right ventricle
Oblique v. of
left atrium
Atrial brs.
Left
atrium
Left ventricle
Superior
vena cava
Right ventricle
Left pulmonary vv.
Cardiac apex
A
Anterior view.
Br. to
sinoatrial node
Right pulmonary vv.
Circumflex br.
Great cardiac v.
Right atrium
Left marginal v.
Coronary sinus
Inferior vena cava
Right coronary a.
Left posterior
ventricular v.
Small cardiac v.
Right posterolateral a.
Right ventricle
Posteroinferior view. Note: The right and
B
left coronary arteries typically anastomose
posteriorly at the left atrium and ventricle.
Posterior interventricular a.
(posterior descending a.)
Left ventricle
Middle cardiac v.
Table 9.3
Branches of the coronary arteries
Left coronary artery
Circumflex br.
• Atrial br.
• Left marginal a.
• Posterior left ventricular br.
Anterior interventricular br.
(left anterior descending)
• Conus br.
• Lateral br.
• Interventricular septal brs.
AV, atrioventricular; SA, sinoatrial.
100
Right coronary artery
Br. to SA node
Conus br.
Atrial br.
Right marginal a.
Posterior interventricular br.
(posterior descending)
• Interventricular septal brs.
Br. to AV node
Right posterolateral a.
Table 9.4
Vein
Divisions of the cardiac veins
Tributaries
Anterior cardiac vv. (not shown)
Drainage to
Right atrium
Anterior interventricular v.
Great cardiac v.
Left marginal v.
Oblique v. of left atrium
Left posterior ventricular v.
Middle cardiac v. (posterior interventricular v.)
Small cardiac v.
Anterior vv. of right ventricle
Right marginal v.
Coronary sinus
Fig. 9.17 Distribution of the coronary arteries
Left coronary a.
Left
ventricle
Interventricular
septum
Right
ventricle
Circumflex br.
Posterior left
ventricular br.
Right
coronary a.
Right
coronary a.
Posterior interventricular br.
Clinical box 9.3
Disturbed coronary blood flow
Although the coronary arteries are connected
by structural anastomoses, they are end
arteries from a functional standpoint. The
most frequent cause of deficient blood flow
is athero­sclerosis, a narrowing of the coronary
lumen due to plaque-like deposits on the
vessel wall. When the decrease in luminal size
(stenosis) reaches a critical point, coronary
blood flow is restricted, causing chest pain
(angina pectoris). Initially, this pain is induced
by physical effort, but eventually it persists
at rest, often radiating to characteristic sites
(e.g., medial side of left upper limb, left side
of head and neck). A myocardial infarction
occurs when deficient blood supply causes
myocardial tissue to die (necrosis). The location and extent of the infarction depends on
the stenosed vessel (see A–E, after Heinecker).
9 Mediastinum
Anterior and posterior views of the heart, with superior views of transverse sections through
the ventricles. The “distribution” of the coronary arteries refers to the area of the myocardium
supplied by each artery, as seen in the transverse views, but the term “dominance” refers to the
artery that gives rise to the posterior interventricular artery, as seen in the anterior and posterior
views. Right coronary artery and branches (green); left coronary artery and branches (red).
Posterior interventricular br.
A
Left coronary dominance (15–17%).
A
A
Supra-apical anterior infarction.
Ascending aorta
R
L
Right
coronary
a.
P
Circumflex br.
Apical anterior infarction.
B
Posterior left
ventricular br.
Posterior interventricular br.
Left
coronary
a.
Area of
deficient
blood flow
Posterior interventricular br.
B
Balanced distribution, right coronary artery dominance (67–70%).
C
Anterior lateral infarction.
DPosterior lateral infarction.
Posterior left
ventricular br.
Right
coronary a.
Posterior interventricular br.
C
Right coronary dominance (~15%).
E
Posterior infarction.
101
Thorax
Conduction & Innervation of the Heart
Contraction of cardiac muscle is modulated by the cardiac conduction
system. This system of specialized myocardial cells (Purkinje fibers)
­generates and conducts excitatory impulses in the heart. The conduc-
tion system contains two nodes, both located in the right atrium: the
sinoatrial (SA) node, known as the pacemaker, and the atrioventricular
(AV) node.
Fig. 9.18 Cardiac conduction system
Aortic arch
Superior
vena cava
Interatrial
bundle
Superior
vena cava
Pulmonary
trunk
Sinoatrial
(SA) node
Atrioventricular
(AV) bundle
(of His)
Sinoatrial (SA)
node
Anterior, middle,
and posterior
internodal
bundles
Left
bundle br.
Left
bundle br.
Right
bundle br.
Right atrium
Right
ventricle
Atrioventricular (AV)
node
Septomarginal
trabecula,
(moderator
band)
Atrioventricular
(AV) node
Right
bundle br.
Anterior
papillary m.
Atrioventricular
(AV) bundle
Purkinje
(of His)
fibers
Interventricular
septum
A
Anterior view. Opened:
All four chambers.
Interventricular
septum
B
Right lateral view. Opened: Right atrium
and ventricle.
Aortic
arch
Pulmonary
trunk
Left atrium
Left bundle br.
Anterior fascicle
Interventricular
septum
Middle fascicle
Posterior fascicle
Left ventricle
C
Left lateral view. Opened:
Left atrium and ventricle.
Cardiac apex
Subendocardial brs.
Clinical box 9.4
Electrocardiogram (ECG)
The cardiac impulse (a physical dipole) travels across
the heart and may be detected with electrodes. The
use of three electrodes that separately record electrical activity of the heart along three axes or vectors
(Einthoven limb leads) generates an electrocardiogram
(ECG). The ECG graphs the cardiac cycle (“heartbeat”),
reducing it to a series of waves, segments, and
intervals. These ECG components can be used to
determine whether cardiac impulses are normal or
abnormal (e.g., myocardial infarction, chamber
enlargement). Note: Although only three leads are
required, a standard ECG examination includes at
least two others (Goldberger, Wilson leads).
102
P wave
R wave
T wave
I
Lead vectors
in Einthoven’s
triangle
II
III
Recording
electrodes
Q wave
A
ECG recording electrodes.
B
ECG.
S wave
ST segment
plexus. Parasympathetic innervation: Preganglionic neurons and fibers
reach the heart via cardiac branches, some of which also arise in the
cervical region. They synapse on postganglionic neurons near the SA
node and along the coronary arteries.
Fig. 9.19 Autonomic innervation of the heart
Dorsal motor
(vagal) nucleus
Superior
cervical ganglion
Superior, middle,
and inferior cervical
cardiac nn.
Vagus n. (CN X)
Middle
cervical ganglion
T1 spinal
cord segment
Stellate ganglion
Sympathetic
trunk
Sympathetic
trunk, inferior
cervical ganglion
Superior and
inferior cervical
cardiac brs.
Cardiac brs. to
cardiac plexus
Thoracic
cardiac brs.
Cardiac plexus
9 Mediastinum
Sympathetic innervation: Preganglionic neurons from T1 to T6 spinal
cord segments send fibers to synapse on postganglionic neurons in
the cervical and upper thoracic sympathetic ganglia. The three cervical
cardiac nerves and thoracic cardiac branches contribute to the cardiac
Cervical cardiac nn.
Aortic arch with
thoracic aortic plexus
Pulmonary a. and
pulmonary vv. with
pulmonary plexus
Cardiac plexus
Cardiac plexus (along
the coronary aa.)
Sinoatrial (SA)
node
B
Autonomic plexuses of the heart, right lateral view. Note the continuity between the cardiac, aortic, and pulmonary plexuses.
Atrioventricular (AV)
node
Myocardium
Hyoid bone
Sympathetic preganglionic fibers
Superior laryngeal n.
Sympathetic postganglionic fibers
Left vagus n.
Right vagus n.
Parasympathetic preganglionic fibers
Sympathetic trunk,
middle cervical
ganglion
Parasympathetic postganglionic fibers
A
Schematic.
Thyroid cartilage
Thyroid gland
Anterior scalene
Left common carotid a.
Brachial plexus
Left recurrent
laryngeal n.
Subclavian a.
Trachea
Brachiocephalic
trunk
Thoracic aortic
plexus
Right recurrent
laryngeal n.
Left vagus n.
Sympathetic
trunk, thoracic
ganglion
Ligamentum
arteriosum
Right vagus n.
Right
phrenic n.
Left
phrenic n.
Superior
vena cava
Pulmonary
plexus
Ascending
aorta
Pulmonary
trunk
Cardiac
plexus
Phrenic n.
(on diaphragm)
C
Autonomic nerves of the heart.
Anterior view of opened thorax.
Fibrous
Gastric plexus
pericardium (opened)
103
Thorax
Pre- & Postnatal Circulation
Fig. 9.20 Prenatal circulation
After Fritsch and Kühnel.
① Oxygenated and nutrient-rich fetal blood from the placenta passes
to the fetus via the umbilical vein.
②A
pproximately half of this blood bypasses the liver (via the ductus
venosus) and enters the inferior vena cava. The remainder enters the
portal vein to supply the liver with nutrients and oxygen.
③B
lood entering the right atrium from the inferior vena cava bypasses
the right ventricle (as the lungs are not yet functioning) to enter the
left atrium via the oval foramen, a right-to-left shunt.
④ Blood from the superior vena cava enters the right atrium, passes
to the right ventricle, and moves into the pulmonary trunk. Most of
this blood enters the aorta via the ductus arteriosus, a right-to-left
shunt.
⑤ The partially oxygenated blood in the aorta returns to the placenta
via the paired umbilical arteries that arise from the internal iliac
arteries.
Aortic arch
④ Ductus arteriosus
Pulmonary aa.
(very little blood flow)
(patent)
Left pulmonary vv.
(very little blood flow)
Left atrium
Superior vena cava
③
Oval foramen
(patent)
Pulmonary trunk
Right atrium
Left ventricle
Right ventricle
Hepatic vv.
Liver
②
Ductus venosus
Anastomosis
between umbilical
v. and portal v.
Portal v.
①
Abdominal
aorta
Umbilical v.
Inferior
vena cava
Umbilical aa.
Common iliac a.
Internal iliac a.
Umbilicus
⑤
Placenta
104
Umbilical aa.
Fig. 9.21 Postnatal circulation
Derivatives of fetal circulatory structures
Table 9.5
After Fritsch and Kühnel.
Fetal structure
② The foramen ovale and ductus arteriosus close, eliminating the fetal
right-to-left shunts. The pulmonary and systemic circulations in the
heart are now separate.
Adult remnant
Ductus arteriosus
Ligamentum arteriosum
Foramen ovale
Oval fossa (fossa ovalis)
Ductus venosus
Ligamentum venosum
Umbilical v.
Round lig. of the liver (ligamentum teres)
Umbilical a.
Medial umbilical lig.
9 Mediastinum
① As pulmonary respiration begins at birth, pulmonary blood pressure
falls, causing blood from the right pulmonary trunk to enter the
pulmonary arteries.
③ As the infant is separated from the placenta, the umbilical arteries
occlude (except for the proximal portions), along with the umbilical
vein and ductus venosus.
④ Blood to be metabolized now passes through the liver.
Aortic arch
② Ligamentum arteriosum
(obliterated ductus
arteriosus)
①
Pulmonary aa.
(perfused)
Left pulmonary
vv. (perfused)
Left atrium
Superior vena cava
②
Oval foramen
(closed)
Pulmonary trunk
Left ventricle
Right atrium
Right ventricle
Hepatic vv.
Liver
④
Ligamentum venosum
(obliterated ductus
venosus)
Clinical box 9.5
Septal defects
Portal v.
Round lig. of liver
(obliterated
umbilical v.)
Abdominal
aorta
③
Inferior
vena cava
Umbilical cord
Septal defects, the most common type of
congenital heart defect, allow blood from
the left chambers of the heart to improperly
pass into the right chambers during systole.
Ventricular septal defect (VSD, shown
below) is a defect in either the membranous
or muscular portion of the ventricular
septum—most commonly the membranous
portion. Patent foramen ovale, the most
prevalent form of atrial septal defect (ASD),
results from improper closure of the fetal
shunt. LV, left ventricle; RV, right ventricle.
Umbilicus
Obliterated umbilical aa.
(medial umbilical ligs.)
LV
RV
105
Thorax
Esophagus
The esophagus is divided into three parts: cervical (C6–T1), thoracic
(T1 to the esophageal hiatus of the diaphragm), and abdominal (the
diaphragm to the cardiac orifice of the stomach). It descends slightly to
the right of the thoracic aorta and pierces the diaphragm slightly to the
left, just below the xiphoid process of the sternum.
C6
Fig. 9.22 Esophagus: Location and constrictions
Cricoid cartilage
Upper esophageal
(pharyngoesophageal)
constriction
Esophageal inlet
Cervical part
Trachea,
thoracic part
Sternum
T4
Thoracic part
Middle esophageal
(thoracic)
constriction
Diaphragm
Abdominal part
Diaphragm
T10
A
Projection of esophagus onto chest wall. Esophageal constrictions
are indicated with arrows.
Lower esophageal
(phrenic)
constriction
Aorta
B
Esophageal constrictions, right lateral view.
Fig. 9.23 Esophagus in situ
Anterior view.
Trachea,
cervical part
Esophagus,
cervical part
Left internal jugular v.
Brachial plexus
Left subclavian a. and v.
Anterior scalene
Brachiocephalic trunk
Left brachiocephalic v.
Right brachiocephalic v.
Parietal pleura,
cervical part
Aortic arch
Ligamentum arteriosum
Azygos v., arch
Left pulmonary a.
Left vagus n.
Right pulmonary a.
Superior and inferior
lobar bronchi
Right pulmonary vv.
Right vagus n.
Thoracic aorta
Pulmonary trunk
Parietal pleura,
mediastinal part
Azygos v.
Thoracic duct
Anterior esophageal
plexus
Parietal pleura,
diaphragmatic part
106
Esophagus,
thoracic part
Central tendon Stomach
of diaphragm
Mucosa, longitudinal folds
Mediastinal part
Muscularis
Diaphragmatic part
Parietal pleura
Longitudinal
layer
Esophageal hiatus
Pharyngeal
raphe
Thyroid
cartilage
Gastroesophageal
junction (Z line)
Inferior pharyngeal
constrictor, thyropharyngeal part
Killian’s
triangle
Inferior pharyngeal
constrictor, cricopharyngeal part
Cricoid
cartilage
Parietal
peritoneum
Peritoneal
cavity
Muscular coat,
circular layer
Trachea
Esophagus
Gastric
fundus
Visceral
peritoneum
9 Mediastinum
Fig. 9.24 Structure of the esophagus
Circular
layer
Gastric
cardia
Gastric
folds (rugae)
Esophagogastric junction, anterior view. A true sphincter is not
B
identifiable at this junction; instead, the diaphragmatic muscle of the
esophageal hiatus functions as a sphincter. It is often referred to as
the “Z line” because of its zigzag form.
Muscular coat,
longitudinal layer
Muscular coat,
circular layer
Submucosa
Mucosa
A
Esophageal wall, oblique left posterior view. Pharynx (p. 650);
trachea (p. 120).
Functional architecture of esophageal muscle.
C
Clinical box 9.6
Esophageal diverticula
Inferior pharyngeal constrictor
Zenker’s diverticulum
• Hypopharyngeal (pharyngo-esophageal) diverticula: Outpouchings
­occurring at the junction of the pharynx and the esophagus. These
include Zenker’s diverticula (70% of cases).
Trachea
Parabronchial diverticulum
Left main bronchus
Diverticula (abnormal outpouchings or sacs) generally develop at weak
spots in the esophageal wall. There are three main types of esophageal
diverticula:
Right main bronchus
Esophagus (thoracic part)
Epiphrenic diverticulum
Diaphragm
• “True” traction diverticula: Protrusion of all wall layers, not typically
­occurring at characteristic weak spots. However, they generally result
from an inflammatory process (e.g., lymphangitis) and are thus common at sites where the esophagus closely approaches the bronchi and
bronchial lymph nodes (thoracic or parabronchial diverticula).
• “False” pulsion diverticula: Herniations of the mucosa and submucosa
through weak spots in the muscular coat due to a rise in esophageal
pressure (e.g., during normal swallowing). These include parahiatal
and epiphrenic diverticula occurring above the esophageal aperture of
the diaphragm (10% of cases).
Esophagus, abdominal part
107
Thorax
Neurovasculature of the Esophagus
Sympathetic innervation: Preganglionic fibers arise from the T2–T6
spinal cord segments. Postganglionic fibers arise from the sympathetic
trunk to join the esophageal plexus. Parasympathetic innervation:
­Preganglionic fibers arise from the dorsal vagal nucleus and travel in
Fig. 9.25 Autonomic innervation
of the esophagus
the vagus nerves to form the extensive esophageal plexus. Note: The
postganglionic neurons are in the wall of the esophagus. Fibers to
the cervical portion of the esophagus travel in the recurrent laryngeal
nerves.
Vagus n. (CN X)
Dorsal motor (vagal) nucleus
Esophagus,
cervical part
Sympathetic
trunk
Esophageal
brs.
T2 spinal cord
segment
Recurrent laryngeal n.
Esophagus, thoracic part
Esophageal plexus
T6 spinal cord
segment
Vagal
trunk
Esophagus, abdominal part
Sympathetic preganglionic fibers
Sympathetic postganglionic fibers
Parasympathetic preganglionic fibers
Parasympathetic postganglionic fibers
Fig. 9.26 Esophageal plexus
Trachea
The left and right vagus nerves initially descend on the
left and right sides of the esophagus. As they begin
to contribute to the esophageal plexus, they shift to
anterior and posterior positions, respectively. As the
vagus nerves continue into the abdomen, they are
named the anterior and posterior vagal trunks.
Sympathetic trunk,
middle cervical
ganglion
Right
subclavian a.
Right recurrent
laryngeal n.
Right vagus n.
Brachiocephalic
trunk
Right recurrent
laryngeal n.
Left recurrent
laryngeal n.
Right vagus n.
Left vagus n.
3rd through
6th thoracic
ganglia
Esophageal brs.
Esophageal
plexus
Left
sympathetic
trunk
Right
sympathetic
trunk
Stomach
Anterior
vagal trunk
108
Left common
carotid a.
Brachial plexus
Left
subclavian a.
First rib
Left vagus n.
Posterior
intercostal a.
Left recurrent
laryngeal n.
Intercostal n.
Aortic arch
Right main
bronchus
Esophagus,
thoracic part
Sympathetic
trunk
Anterior vagal
trunk with
esophageal
plexus
Left main
bronchus
Thoracic
aorta
Sympathetic
trunk
Greater
splanchnic n.
Caval opening
Anterior
gastric plexus
A
Anterior view. Note the postganglionic sympathetic contribution to the
­esophageal plexus.
Esophagus,
cervical part
Diaphragm
Anterior
gastric plexus
Stomach
B
Esophageal plexus in situ. Anterior view.
Fig. 9.27 Esophageal arteries
Left
vagus n.
Anterior view.
Esophageal
plexus
Inferior
thyroid a.
Right common
carotid a.
Left common
carotid a.
Thyrocervical
trunk
Posterior
vagal
trunk
Esophageal brs.
Left subclavian a.
Internal thoracic a.
Brachiocephalic
trunk
Trachea
Stomach
Anterior scalene
9 Mediastinum
Right
vagus n.
Vertebral a.
Aortic arch
Posterior
gastric plexus
Left main
bronchus
C
Posterior view.
Posterior
intercostal aa.
Esophageal brs.
(from thoracic aorta)
Thoracic aorta
Diaphragm
Gastric fundus
Esophageal br.
Left inferior phrenic a.
Fig. 9.28 Esophageal veins
Anterior view.
Anterior
scalene
Left gastric a.
Celiac trunk
Inferior
thyroid v.
Left internal
jugular v.
Common
hepatic a.
Splenic a.
Abdominal aorta
Esophageal vv.
Left external
jugular v.
Right brachiocephalic v.
Superior
vena cava
Left subclavian v.
Left brachiocephalic v.
Accessory
hemiazygos v.
Esophageal vv.
Azygos v.
Posterior
intercostal vv.
Table 9.6
Origin of
esophageal arteries
Drainage of
esophageal veins
Diaphragm
Inferior thyroid a.
Inferior thyroid v.
Esophageal vv.
Rarely direct brs. from
thyrocervical trunk or
common carotid a.
Left brachiocephalic v.
Hemiazygos v.
Part
Cervical
Left
gastric v.
Blood vessels of the esophagus
Thoracic
Aorta (four or five esophageal
aa.)
Upper left: Accessory
hemiazygos v. or left
brachiocephalic v.
Lower left: Hemiazygos v.
Right side: Azygos v.
Abdominal
Left gastric a.
Left gastric v.
109
Thorax
Lymphatics of the Mediastinum
The superior phrenic lymph nodes drain lymph from the diaphragm,
pericardium, lower esophagus, lung, and liver into the broncho­
mediastinal trunk. The inferior phrenic lymph nodes, found in the
a­ bdomen, collect lymph from the diaphragm and lower lobes of the
lung and convey it to the lumbar trunk. Note: The pericardium may also
drain superiorly to the brachiocephalic lymph nodes.
Esophagus
Fig. 9.29 Lymph nodes of the
mediastinum and thoracic cavity
Trachea
Left jugular trunk
Left anterior oblique view.
Thoracic duct at junction of left
subclavian and internal jugular veins
Right brachiocephalic vein
Left brachiocephalic vein
Brachiocephalic l.n.
Paratracheal l.n.
Superior vena cava
Thoracic duct
Tracheobronchial l.n.
Intercostal lymphatics
Prevertebral l.n.
Fibrous
pericardium
Superior
phrenic l.n.
Diaphragm
Celiac l.n.
Celiac trunk
Abdominal
aorta
Stomach
Fig. 9.30 Lymphatic drainage
of the heart
Trachea
A unique “crossed” drainage pattern exists
in the heart: lymph from the left atrium and
ventricle drains to the right venous junction,
whereas lymph from the right atrium and
ventricle drains to the left venous junction.
Junction of right subclavian
and internal jugular vv.
Superior vena cava
Superior vena cava
Left ventricle
Trachea
Aortic arch
Right coronary
trunk
Left ventricle
Trachea
Inferior tracheobronchial l.n.
Bronchopulmonary l.n.
Left atrium
Left coronary trunk
C
Posterior view.
110
Right ventricle
B
Lymphatic drainage of the right chambers,
anterior view.
Left coronary
trunk
A
Lymphatic drainage of the left chambers,
anterior view.
Aortic arch
Bronchopulmonary l.n.
Inferior
tracheobronchial l.n.
Right ventricle
Junction of left subclavian
and internal jugular vv.
Superior vena cava
Bronchopulmonary l.n.
Right atrium
Right coronary trunk
the upper half drains cranially, and the lower half drains inferiorly via the
superior phrenic lymph nodes. The bronchopulmonary and paratracheal
nodes drain lymph from the lungs, bronchi, and trachea into the bronchomediastinal trunk (see p. 128).
Fig. 9.31 Mediastinal lymph nodes
Paraesophageal l.n.
Esophagus
9 Mediastinum
The paraesophageal nodes drain the esophagus. Lymphatic drainage
of the cervical part of the esophagus is primarily cranial, to the deep
cervical lymph nodes and then to the jugular trunk. The thoracic part
of the esophagus drains to the bronchomediastinal trunks in two parts:
Trachea
Paratracheal l.n.
Right main
bronchus
Left main
bronchus
Inferior tracheobronchial l.n.
Paraesophageal l.n.
Diaphragm
Inferior phrenic l.n.
Cardiac lymphatic
ring (inconstant)
Stomach
Left internal
jugular v.
A
Anterior view of opened thorax.
Left common
carotid a.
Esophagus
Trachea
Left subclavian
a. and v.
Paraesophageal l.n.
Superior vena cava
Bronchopulmonary l.n.
Aortic arch
Azygos v.
Left pulmonary a.
Left main bronchus
Tracheobronchial l.n.
Bronchopulmonary l.n.
Paraesophageal l.n.
Fibrous
pericardium
Inferior vena cava
Diaphragm
B
Posterior view of mediastinal lymph nodes.
111
10
Pulmonary Cavities
Thorax
Pulmonary Cavities
The paired pulmonary cavities contain the left and right lungs. They
are completely separated from each other by the media­stinum and
are under negative atmospheric pressure (see respiratory mechanics,
pp. 122–123). The left pulmonary cavity is slightly smaller than the
right, especially anteriorly, due to the asymmetrical position of the
heart in the mediastinum, with the greater mass on the left. This causes
a shift of some of the boun­daries of the parietal pleura and lung on
the left side at the level of the heart, as reflected in the difference in
thoracic landmarks found at the intersection of the anterior border of
the pulmonary cavities with certain reference lines on the left and right.
Fig. 10.1 Boundaries of the lungs and pulmonary cavities
The upper red dot on each reference line is the inferior boundary of the
lung and the lower blue dot is the inferior boundary of the pulmonary
cavity.
Midclavicular Sternal
line
line
A
Anterior view.
B
Posterior view.
Paravertebral
line
Scapular
line
Parietal
pleura
Parietal
pleura
Midaxillary
line
Midaxillary
line
Costodiaphragmatic
recess of
pulmonary
cavity
Costodiaphragmatic
recess of
pulmonary
cavity
C
Right lateral view.
Table 10.1
112
DLeft lateral view.
Pulmonary cavity boundaries and reference points
Reference line
Right lung
Right parietal pleura
Left lung
Left parietal pleura
Sternal line (STL)
6 rib
7 rib
4 rib
4th rib
Midclavicular line (MCL)
6th rib
8th costal cartilage
6th rib
8th rib
Midaxillary line (MAL)
8 rib
10 rib
8 rib
10th rib
Scapular line (SL)
10 rib
11 rib
10 rib
11th rib
Paravertebral line (PV)
10th rib
T12 vertebra
10th rib
T12 vertebra
th
th
th
th
th
th
th
th
th
Fig. 10.2 Parietal pleura
The pulmonary cavity is bounded by two serous layers. The visceral
pleura covering the lungs, and parietal pleura lining the inner surfaces
of the thoracic cavity. The four divisions of the parietal pleura (costal,
diaphragmatic, mediastinal, and cervical) are continuous.
Cervical part
Visceral pleura
Parietal pleura,
diaphragmatic part
Intercostal v.,
a., and n.
Diaphragm
Parietal pleura,
costal part
Costal part
Parietal peritoneum
10 Pulmonary Cavities
Right lung
8th rib
Visceral peritoneum
Mediastinal
part
Diaphragmatic
part
Pericardial
sac
A
Parts of the parietal pleura. Opened: Right
pleural cavity, anterior view.
Costodiaphragmatic
recess
Costal
groove
Endothoracic fascia
External
intercostal
Liver
Innermost
intercostal
Internal
intercostal
B
Costodiaphragmatic recess, coronal section, anterior view.
Reflection of the diaphragmatic pleura onto the inner
­thoracic wall (becoming the costal pleura) forms the
costodiaphragmatic recess.
Costomediastinal
recess
Fibrous
Serous
pericardium pericardium
Parietal pleura,
mediastinal part
Left lung,
superior lobe
Right lung,
superior lobe
Horizontal
fissure
Right lung,
middle lobe
Parietal pleura,
costal part
Visceral pleura
Oblique
fissure
Oblique
fissure
Left
main
broncus
Right lung,
inferior lobe
Left lung,
inferior lobe
Phrenic n.
C
Transverse section at T7, inferior view. Reflection
of the costal pleura onto the pericardium forms
the costomediastinal recess.
Right Sympathetic Spinal
Azygos v., Hemiazygos v.
cord thoracic duct,
trunk
main
bronchus
and left vagus n.
Parietal pleura,
costal part
Thoracic
aorta
113
Thorax
Pleura: Subdivisions, Recesses & Innervation
Fig. 10.3 Pleura and its divisions
The anterior thoracic wall and costal portion of the parietal pleura have
been removed to show the lungs in situ.
Parietal pleura,
mediastinal part
Superior
lobe
Parietal pleura,
costal part
Internal
thoracic
a. and v.
Lung with
visceral pleura
Middle
lobe
Fibrous
pericardium
Inferior
lobe
Parietal pleura,
mediastinal part
Parietal pleura,
diaphragmatic part
Fig. 10.4 Innervation of the pleura
The costal and cervical portions and the periphery of the diaphragmatic
portion of the parietal pleura are innervated by the intercostal nerves.
The mediastinal and central portions of the diaphragmatic pleura are
innervated by the phrenic nerves. The visceral pleura covering the lung
itself receives its innervation from the autonomic nervous system.
Parietal pleura innervated by intercostal nn.
Parietal pleura innervated by phrenic n.
Visceral pleura innervated by autonomic nn.
114
Fig. 10.5 Costomediastinal and
costodiaphragmatic recesses
Parietal pleura,
mediastinal part
Costomediastinal
recess
Pericardiacophrenic
a. and v., phrenic n.
Internal thoracic
a. and v.
10 Pulmonary Cavities
On the left side of the thorax, an examiner’s
fingertips are placed in the costomediastinal
and costodiaphragmatic recesses. These
recesses are formed by the acute reflection
of the costal part of the parietal pleura onto
the fibrous pericardium as mediastinal pleura
(costomediastinal) or on to the diaphragm as
diaphragmatic pleura (costodiaphragmatic).
Parietal pleura,
costal pleura
Fibrous
pericardium
Costodiaphragmatic
recess
Fig. 10.6 Pleural recesses
Transverse section at T8, superior view.
Costomediastinal
recess
Fibrous
pericardium
Anterior
mediastinum
Sternum,
body
Costomediastinal
recess
Internal thoracic
a. and v.
Serous pericardium,
parietal layer
Parietal pleura,
diaphragmatic part
Phrenic n.,
pericardiacophrenic
a. and v.
Parietal pleura,
costal part
Diaphragm,
costal part
Phrenic n.,
pericardiacophrenic
a.and v.
Costodiaphragmatic
recess
Inferior vena
cava
Diaphragm,
central
tendon
Esophagus
Parietal pleura,
mediastinal part
Thoracic
duct
Hemiazygos v.
Azygos v.
Costodiaphragmatic
recess
Left sympathetic
trunk
Thoracic
aorta
Right sympathetic
trunk
115
Thorax
Lungs
Fig. 10.7 Lungs in situ
Mediastinum
The left and right lungs occupy the full volume of the pleural cavity. Note that the left
lung is slightly smaller than the right due to
the asymmetrical position of the heart.
Superior lobe
Superior lobe
Horizontal fissure
Right
lung
Middle lobe
Oblique fissure
Oblique fissure
Left
lung
Inferior lobe
Inferior lobe
A
Topographical relations of the lungs,
transverse section, inferior view.
Esophagus
Descending
aorta
Left subclavian a. and v.
Brachiocephalic
trunk
Left brachiocephalic v.
Parietal pleura,
cervical part
Aortic arch
Pulmonary apex
Right lung, superior lobe
Superior vena cava
Left pulmonary a.
Right pulmonary a.
Superior and
inferior lobar
bronchi
Right pulmonary vv.
Left lung,
superior lobe
Right lung,
horizontal fissure
Thoracic
aorta
Pulmonary
trunk
Right lung,
middle lobe
Parietal pleura,
mediastinal part
Left lung,
oblique fissure
Right lung,
oblique fissure
Parietal pleura,
costal part
Right lung,
inferior lobe
Left lung,
inferior lobe
Costodiaphragmatic
recess
Diaphragm
B
Anterior view with lungs retracted.
116
Parietal pleura,
diaphragmatic part
Esophagus,
thoracic part
Central tendon
of diaphragm
Parietal layer of
serous pericardium
Fibrous
pericardium
Fig. 10.8 Gross anatomy of the lungs
extends into the root of the neck. The hilum is the location at which the
bronchi and neurovascular structures connect to the lung.
Apex
10 Pulmonary Cavities
The oblique and horizontal fissures divide the right lung into three
lobes: superior, middle, and inferior. The oblique fissure divides the
left lung into two lobes: superior and inferior. The apex of each lung
Apex
Superior
lobe
Superior
lobe
Anterior border
(inserts into costomediastinal recess)
Costal
surface
Oblique
fissure
Anterior border
(inserts into costomediastinal recess)
Horizontal
fissure
Middle
lobe
Costal
surface
Inferior
lobe
Inferior
lobe
Lingula
Oblique fissure
Inferior border (inserts into
costodiaphragmatic recess)
Inferior border (inserts into
costodiaphragmatic recess)
A
Right lung, lateral view.
B
Left lung, lateral view.
Apex
Branches of right
pulmonary a.
Mediastinal
surface
Anterior
border
Hilum
Horizontal
fissure
Apex
Superior lobe
Superior lobar
bronchus
Inferior and
middle lobar
bronchi
(common origin)
Branches
of right
pulmonary vv.
Middle lobe
Diaphragmatic surface
(base of lung)
C
Right lung, medial view.
Costal surface,
vertebral part
Pulmonary
lig.
Branches of
left pulmonary a.
Oblique
fissure
Superior and
inferior lobar
bronchi
Hilum
Branches
of left
pulmonary vv.
Aortic
impression
Cardiac
impression
Inferior lobe
Cardiac
notch
Costal surface
(vertebral part)
Inferior border
(inserts into costodiaphragmatic recess)
Inferior border (inserts into
costodiaphragmatic recess)
Mediastinal
surface
Anterior
border
Oblique fissure
Inferior lobe
Cardiac
impression
Superior
lobe
Lingula
Pulmonary lig.
Diaphragmatic surface
(base of lung)
DLeft lung, medial view.
117
Thorax
Bronchopulmonary Segments of the Lungs
(segmental) bronchus. Note: These subdivisions are not defined by
surface boundaries but by origin.
The lung lobes are subdivided into bronchopulmonary segments,
the smallest resectable portion of a lung, each supplied by a tertiary
Fig. 10.9 Segmentation of the lung
Anterior view. See pp. 120–121 for details of
the trachea and bronchial tree.
Trachea and bronchial
tree
Right
lung
Left
lung
Right lung
Left lung
I
I
II
II
I
I
I
II
I
II
II
III
II
III
III
III
Horizontal
fissure
IV
IV
IV
IV VI
V
VIII
X
VIII
Oblique
fissure
Oblique V
VII
fissure
IX
V
IV
V
Oblique
fissure
III
III
Horizontal
fissure
X
IV
VI
VII, VIII
V
Oblique
fissure
V
IX
VII, VIII VIII
VII, VIII
Fig. 10.10 Anteroposterior bronchogram
Anterior view of right lung.
Table 10.2
Segmental architecture of the lungs
Each segment is supplied by a segmental bronchus of the same name (e.g., the apical segmental bronchus
supplies the apical segment). See pp. 120–121 for details of the trachea and bronchial tree.
Right lung
Left lung
Superior lobe
I
Apical segment
II
Posterior segment
III
Apicoposterior segment
Anterior segment
Middle lobe
I
II
III
Lingula
IV
Lateral segment
Superior lingular segment
IV
V
Medial segment
Inferior lingular segment
V
Inferior lobe
118
VI
Superior segment
VI
VII
Medial basal segment
VII
VIII
Anterior basal segment
VIII
IX
Lateral basal segment
IX
X
Posterior basal segment
X
Fig. 10.11 Right lung: Bronchopulmonary segments
I
II
II
II
III
III
VI
VI
Horizontal
fissure
V
VI
X
Oblique
fissure
IV
VIII
VII
IX
X
VIII
X
IX
A
Medial view.
B
Posterior view.
V
VIII
10 Pulmonary Cavities
I
I
IX
C
Lateral view.
Fig. 10.12 Left lung: Bronchopulmonary segments
I
I
I
II
II
Oblique
fissure
II
III
III
IV
III
VI
VI
VI
IV
IV
VII,
VIII
V
X
IX
V
X
VII, VIII
IX
A
Medial view.
VII, VIII
B
Posterior view.
IX
X
C
Lateral view.
Clinical box 10.1
Lung resections
Lung cancer, emphysema, or tuberculosis may necessitate the surgical
removal of damaged portions of the lung. Surgeons exploit the anatomical
subdivision of the lungs into lobes and segments when excising damaged
tissue.
Trachea
Segment I
of right lung
Right
lung
Superior lobe of
right lung
Left
lung
A
Segmentectomy (wedge resection): Removal of one or
more segments.
B
Lobectomy: Removal of lobe.
C
Pneumonectomy: Removal of
entire lung.
119
Thorax
Trachea & Bronchial Tree
At or near the level of the sternal angle (T4/T5), the lowest tracheal
cartilage extends anteroposteriorly, forming the carina. The trachea
bifurcates at the carina into the right and left main bronchi. Each
bronchus gives off lobar branches to the corresponding lung.
Fig. 10.13 Trachea
See p. 530 for the structures of the thyroid.
Cervical part
Tracheal
bifurcation
Thoracic
part
Right main
bronchus
Trachea
Left main
bronchus
Thyroid
cartilage
Median
cricothyroid lig.
Cricoid
cartilage
A
Projection of trachea onto chest.
Tracheal
cartilages
Thyroid cartilage
Anular ligs.
Arytenoid
cartilage
Right
main
bronchus
Cricoid
cartilage
Membranous
posterior wall (with
tracheal glands)
Tracheal
cartilages
Left
main
bronchus
I
Right
superior lobar
bronchus
Position of carina
(at tracheal
bifurcation)
Right
middle lobar
bronchus
Right
main
bronchus
IV
X
II
III
IV
Left
main
bronchus
VIII
VII
IX
X
V
Tracheal
bifurcation
Right/left
inferior lobar
bronchi
Left
superior
lobar
bronchus
VI
VIII
X
VII
IX
IX
B
Anterior view.
Clinical box 10.2
IV
VI
Foreign body aspiration
V
VIII
VII
IX
Posterior view with opened posterior wall.
C
120
V
VII
III
VI
VI
VIII
I
V
III
III
IV
I
II
II
Mucosa
II
I
X
Toddlers are at particularly high risk of potentially fatal aspiration of
foreign bodies. In general, foreign bodies are more likely to become
lodged in the right main bronchus than the left: the left bronchus
diverges more sharply at the tracheal bifurcation to pass more
horizontally over the heart, whereas the right bronchus is relatively
straight and more in line with the trachea.
The conducting portion of the bronchial tree extends from the tracheal
bifurcation to the terminal bronchiole, inclusive. The respiratory portion
consists of the respiratory bronchiole, alveolar ducts, alveolar sacs, and
alveoli.
10 Pulmonary Cavities
Fig. 10.14 Bronchial tree
Smooth muscle
(lattice arrangement)
Segmental
bronchus
Cartilaginous
plate
Elastic
fibers
Pulmonary
alveolus
Large
subsegmental
bronchus
Respiratory
bronchioles
Conduction
portion of
airway
Small
subsegmental
bronchus
Interalveolar
septum
Alveolar
duct
Alveolar
sac
Alveolus
Respiratory
bronchiole
Respiratory
portion of
airway
Pulmonary
alveoli
Bronchiole
(cartilage-free
wall)
Terminal
bronchiole
Acinus
B
Respiratory portion of the bronchial tree.
see B
Alveolar
sacs
Clinical box 10.3
A
Divisions of the bronchial tree.
Respiratory compromise
The most common cause of respiratory compromise at the bronchial level
is asthma. Compromise at the alveolar level may result from increased
diffusion distance, decreased aeration (emphysema), or fluid infiltration
(e.g., pneumonia).
Capillary
Capillary
Type II
Surfactant endothelial cell lumen pneumocyte
Alveolar
lumen
Erythrocyte
Diffusion distance: Gaseous exchange takes place between the alveolar
and capillary lumens in the alveoli (see Fig. 10.14C). At these sites, the
basement membranes of capillary endothelial cells are fused with those
of type I alveolar epithelial cells, lowering the exchange distance to 0.5
µm. Diseases that increase this diffusion distance (e.g., edematous fluid
collection or inflammation) result in compromised respiration.
Condition of alveoli: In diseases like emphysema, which occurs in chronic
obstructive pulmonary disease (COPD), alveoli are destroyed or damaged.
This reduces the surface area available for gaseous exchange.
Alveolar
macrophage
Type I
pneumocyte
Elastic fibers
in the
interalveolar
septum
Fusion of the
basement
membranes
Production of surfactant: Surfactant is a protein-phospholipid film that
lowers the surface tension of the alveoli, making it easier for the lung to
expand. The immature lungs of a preterm infant often fail to produce
sufficient surfactant, leading to respiratory problems. Surfactant is
produced and absorbed by alveolar epithelial cells (pneumocytes). Type I
alveolar epithelial cells absorb surfactant; type II produce and release it.
Epithelial lining of the alveoli.
C
121
Thorax
Respiratory Mechanics
The mechanics of respiration are based on a rhythmic increase and
decrease in thoracic volume, with an associated expansion and contraction of the lungs. Inspiration (red): Contraction of the diaphragm leaflets
lowers the diaphragm into the inspiratory position, increasing the volume
of the pleural cavity along the vertical axis. Contraction of the thoracic
muscles (external intercostals with the scalene, intercartilaginous, and
posterior serratus muscles) elevates the ribs, expanding the pleural cavity
along the sagittal and transverse axes (Fig. 10.16A,B). Surface tension
in the pleural space causes the visceral and parietal pleura to adhere;
thus, changes in thoracic volume alter the volume of the lungs. This is
particularly evident in the pleural recesses: at functional residual capacity
(resting position between inspiration and expiration), the lung does not
fully occupy the pleural cavity. As the pleural cavity expands, a negative
intrapleural pressure is generated. The air pressure differential results in
an influx of air (inspiration). Expiration (blue): During passive expiration,
the muscles of the thoracic cage relax and the diaphragm returns to
its expiratory position. Contraction of the lungs increases the pulmonary pressure and expels air from the lungs. For forcible expiration, the
internal intercostal muscles (with the transverse thoracic and subcostal
mucosa) can actively lower the rib cage more rapidly and to a greater
extent than through passive elastic recoil.
Fig. 10.15 Respiratory changes in thoracic volume
1st rib
Inspiratory position (red); expiratory position (blue).
Sternum
Expiratory position
Diaphragm
Inspiratory position
Fig. 10.16 Inspiration: Pleural cavity expansion
T12 vertebra
Expansion
(vertical axis)
Inspiration
1st rib
Thoracic
inlet
Fig. 10.18 Respiratory changes in
lung volume
Diaphragm
Expansion
(transverse axis)
Expansion
(sagittal axis)
A
Anterior view.
B
Left lateral view.
Epigastric
angle
Inferior border of lung (full expiration)
C
Anterolateral view.
Fig. 10.17 Expiration: Pleural cavity contraction
Contraction
(vertical axis)
Expiration
Contraction
(transverse axis)
A
Anterior view.
122
Contraction
(sagittal axis)
B
Left lateral view.
C
Anterolateral view.
Inferior border of lung (full inspiration)
Fig. 10.19 Inspiration: Lung expansion
Fig. 10.20 Expiration: Lung contraction
Right lung (full expiration)
Pleural
space
As the volume of the lung changes with the
volume of the thoracic cavity, the entire
bronchial tree moves within the lung. These
structural movements are more pronounced
in portions of the bronchial tree distant from
the pulmonary hilum.
Trachea
Diaphragm
Lung
(full expiration)
10 Pulmonary Cavities
Right lung (full inspiration)
Fig. 10.21 Movements of the lung
and bronchial tree
Diaphragm
Costodiaphragmatic recess
Costodiaphragmatic recess
Lung
(full inspiration)
Clinical box 10.4
Pneumothorax
The pleural space is normally sealed from the outside environment. Injury
to the parietal pleura, visceral pleura, or lung allows air to enter the pleural
cavity (pneumothorax). The lung collapses due to its inherent elasticity, and
the patient’s ability to breathe is compromised. The uninjured lung continues
to function under normal pressure variations, resulting in “mediastinal
flutter”: the mediastinum shifts toward the normal side during inspiration
and returns to the midline during expiration. Tension (valve) pneumothorax
occurs when traumatically detached and displaced tissue covers the defect
in the thoracic wall from the inside. This mobile flap allows air to enter, but
not escape, the pleural cavity, causing a pressure buildup. The mediastinum
shifts to the normal side, which may cause kinking of the great vessels and
prevent the return of venous blood to the heart. Without treatment, tension
pneumothorax is invariably fatal.
Airflow
into pleural
defect
Normal airflow during
inspiration
Right
lung
Left
lung
Collapsed
lung
Inspiration
Cardiac shift
Positive pressure
in pleural cavity
Normal airflow during
expiration
Airflow out
of pleural
defect
Expiration
Cardiac shift
A
Normal respiration.
Pleural
defect during
inspiration
B
Pneumothorax.
“Empty” pleural
cavity at
atmospheric
pressure
Collapsed
lung
One-way
“valve”
Cardiac shift
C
Tension pneumothorax.
123
Thorax
Pulmonary Arteries & Veins
The pulmonary trunk arises from the right ventricle and divides into a
left and right pulmonary artery for each lung. The paired pulmonary
veins open into the left atrium on each side. The pulmonary arteries
accompany and follow the branching of the bronchial tree, whereas the
pulmonary veins do not, being located at the margins of the pulmonary
lobules.
Fig. 10.22 Pulmonary arteries and veins
Anterior view.
Right
pulmonary a.
Right internal
jugular v.
Left pulmonary a.
Pulmonary
trunk
Left internal
jugular v.
Right
subclavian v.
Left
subclavian v.
Right brachiocephalic v.
Left brachiocephalic v.
Superior vena cava
Left
pulmonary vv.
Right pulmonary vv.
Inferior
vena cava
A
Projection of pulmonary arteries on chest wall.
B
Projection of pulmonary veins on chest wall.
Trachea
Left lung
Right lung
Superior lobe
Superior lobe
Aortic arch
Right main
bronchus
Left main
bronchus
Right
pulmonary a.
Left pulmonary a.
Superior right
pulmonary v.
Superior left
pulmonary v.
Inferior right
pulmonary v.
Inferior left
pulmonary v.
Superior
vena cava
Ascending aorta
Pulmonary trunk
Right atrium
Left ventricle
Middle lobe
Inferior lobe
Inferior
vena cava
C
Distribution of the pulmonary arteries and veins, anterior view.
124
Right
ventricle
Cardiac apex
Inferior lobe
Fig. 10.23 Pulmonary arteries
Fig. 10.24 Pulmonary veins
Left common
carotid a.
Left subclavian a.
S
Aortic arch
Right
pulmonary a.
②①
⑪ ⑫
③
Middle
lobe a.
⑬
⑥
④
⑮
⑤
A
Schematic.
Table 10.3
⑩
⑦
⑧⑨
Pulmonary
trunk
⑭
⑲⑱
Ligamentum
arteriosum
Left
pulmonary a.
⑯
F
Right/left
superior
pulmonary v.
G
L
Right/left
inferior
pulmonary v.
K J
⑰
Table 10.4
Left pulmonary artery
⑪
②
Posterior segmental a.
⑫
①
Apical v.
③
Anterior segmental a.
⑬
②
Posterior v.
③
Middle lobe arteries
⑤
Medial segmental a.
⑥
Superior segmental a.
⑮
⑦
Anterior basal segmental a.
⑯
⑧
Lateral basal segmental a.
⑰
⑨
Posterior basal segmental a.
⑱
⑩
Medial basal segmental a.
⑲
B
Pulmonary arteriogram, arterial
phase, anterior view.
(Reproduced from
Moeller TB, Reif E.
Pocket Atlas of Radiographic Anatomy,
3rd ed. New York,
NY: Thieme; 2010.)
Left pulmonary vein
Apicoposterior v.
⑩
Anterior v.
Anterior v.
⑪
④
Middle lobe v.
Lingular v.
⑫
⑤
Superior v.
⑬
⑥
Common basal v.
⑭
⑦
Inferior basal v.
⑮
⑧
Superior basal v.
⑯
⑨
Anterior basal v.
⑰
⑭
Inferior lobe arteries
N
Superior pulmonary veins
Apical segmental a.
Lingular a.
V
Pulmonary veins and their tributaries
①
Lateral segmental a.
X
CB
H
Right pulmonary vein
Superior lobe arteries
④
Ö
Ä
Y
A
Schematic.
Pulmonary arteries and their branches
Right pulmonary artery
D A
10 Pulmonary Cavities
Brachiocephalic trunk
Inferior pulmonary veins
B
Pulmonary arteriogram, venous
phase, anterior view.
(Reproduced from
Moeller TB, Reif E.
Pocket Atlas of Radiographic Anatomy,
3rd ed. New York,
NY: Thieme; 2010.)
Clinical box 10.5
Pulmonary embolism
Potentially life-threatening pulmonary embolism occurs when blood
clots migrate through the venous system and become lodged in one of
the arteries supplying the lungs. Symptoms include dyspnea (difficulty
breathing) and tachycardia (increased heart rate). Most pulmonary emboli
originate from stagnant blood in the veins of the lower limb and pelvis
(venous thromboemboli). Causes include immobilization, disordered blood
coagulation, and trauma. Note: A thromboembolus is a thrombus (blood clot)
that has migrated (embolized).
125
Thorax
Neurovasculature of the Tracheobronchial Tree
Fig. 10.25 Pulmonary vasculature
Bronchial a.
The pulmonary system is responsible for
gaseous exchange within the lung. Pulmonary arteries (shown in blue) carry deoxygenated blood and follow the bronchial tree. The
pulmonary vein and its tributaries (red) is
the only vein in the body carrying oxygenated
blood, which it receives from the alveolar
capillaries at the periphery of the lobule.
Smooth
muscle
Br. of pulmonary a.
(deoxygenated blood)
Respiratory
bronchiole
Tributary of
pulmonary v.
(oxygenated
blood)
Capillary bed
on an alveolus
Pulmonary
alveolus
Fibrous septum
between
pulmonary
lobules
Pulmonary
alveolus
Subpleural
connective
tissue
Fig. 10.26 Arteries of the tracheobronchial tree
The bronchial tree receives its nutrients via the
bronchial arteries, found in the adventitia of the
airways. Typically, there are one to three bronchial
arteries arising directly from the aorta. Origin from
a posterior intercostal artery may also occur.
Trachea
Brachiocephalic trunk
Ascending
aorta
Posterior
intercostal a.
Left subclavian a.
Left common
carotid a.
Aortic arch
Bronchial
brs. (from the
thoracic aorta)
Right main
bronchus
Left main
bronchus
Superior lobe
bronchus
Bronchial
brs. (from a
posterior intercostal a.)
Superior lobe
bronchus
Inferior lobe
bronchus
Middle lobe
bronchus
Posterior
intercostal aa.
Inferior lobe
bronchus
Thoracic
aorta
126
Fig. 10.27 Veins of the tracheobronchial
tree
Trachea
Right brachiocephalic v.
Accessory
hemiazygos v.
Left main
bronchus
Superior vena cava
Bronchial vv.
(opening into
the accessory
hemiazygos v.)
Superior lobe
bronchus
10 Pulmonary Cavities
Left brachiocephalic v.
Inferior
thyroid v.
Superior lobe
bronchus
Bronchial vv.
(opening into
the azygos v.)
Middle lobe
bronchus
Inferior lobe
bronchus
Inferior lobe
bronchus
Azygos v.
Fig. 10.28 Autonomic innervation of
the tracheobronchial tree
Sympathetic innervation (red);
parasympathetic innervation (blue).
Hemiazygos v.
Vagus n. (CN X)
Dorsal motor
(vagal) nucleus
Middle cervical
ganglion
Postganglionic
fibers (to
cardiac plexus )
Larynx,
thyroid cartilage
Superior
laryngeal n.
Cervicothoracic
(stellate) ganglion
Recurrent
laryngeal n.
T1 spinal cord
segment
Laryngopharygeal
brs.
2nd - 5th thoracic
sympathetic
ganglia
Autonomic brs.
to trachea
Pulmonary plexus
Greater splanchnic
(to abdomen)
Trachea
Bronchial brs.
in pulmonary plexus
Sympathetic preganglionic fibers
Sympathetic postganglionic fibers
Right main
bronchus
Left main
bronchus
Parasympathetic preganglionic fibers
Parasympathetic postganglionic fibers
127
Thorax
Lymphatics of the Pleural Cavity
The lungs and bronchi are drained by two lymphatic drainage systems.
The peribronchial network follows the bronchial tree, draining lymph
from the bronchi and most of the lungs. The subpleural network collects lymph from the peripheral lung and visceral pleura.
Fig. 10.29 Lymphatic drainage of the pleural cavity
and thoracic wall
Trachea
To right bronchomediastinal trunk
To left bronchomediastinal trunk
Right lung
Left lung
A
Peribronchial network, coronal section, anParatracheal l.n.
terior view. (Intra)pulmonary nodes along
Superior tracheothe bronchial tree drain lymph from the
bronchial l.n.
lungs into the bronchopulmonary (hilar)
nodes. Lymph then passes sequentially
To inferior
through the inferior and superior tracheo- tracheobronchial l.n.
bronchial nodes, paratracheal nodes,
bronchomediastinal trunk, and finally to
the right lymphatic or thoracic duct.
Note: Significant amounts of lymph from
the left lower lobe drain to the right supeDiaphragm
rior tracheobronchial nodes.
Inferior tracheobronchial l.n.
Drainage through
diaphragm
Inferior phrenic l.n.
Parasternal l.n.
Sternum
Bronchopulmonary l.n.
Intrapulmonary l.n.
Tracheobronchial l.n.
Paratracheal l.n.
Lymphatics
in the trunk
wall
Peribronchial
network
B
Subpleural and thoracic wall networks,
transverse section, superior view.
128
Subpleural
network
Trachea
Intercostal l.n.
10 Pulmonary Cavities
Fig. 10.30 Lymph nodes of the pleural cavity
Anterior view of pulmonary nodes.
Right internal
jugular v.
Right
jugular trunk
Right subclavian v.
Left
jugular trunk
Trachea
Deep cervical l.n.
Thoracic duct
Right subclavian trunk
Right bronchomediastinal trunk
Left subclavian trunk
Left bronchomediastinal trunk
Paratracheal l.n.
Superior tracheobronchial l.n.
Right main
bronchus
Inferior tracheobronchial l.n.
Left main
bronchus
Bronchopulmonary l.n.
Intrapulmonary l.n.
Thoracic
aorta
Right lung
Left lung
Clinical box 10.6
Carcinoma of the Lung
Carcinoma of the lung accounts for ≈ 20% of all cancers and is mainly
caused by cigarette smoking. It arises first in the lining of the bronchi and
metastasizes quickly to bronchopulmonary lymph nodes and subsequently
to other node groups, including supraclavicular nodes. It can also spread via
the blood to the lungs, brain, bone, and suprarenal glands. Lung cancer can
invade adjacent structures such as the phrenic nerve, resulting in paralysis of
a hemidiaphragm, or the recurrent laryngeal nerve, resulting in hoarseness
due to paralysis of the vocal cord.
129
11
Sectional & Radiographic Anatomy
Thorax
Sectional Anatomy of the Thorax
Fig. 11.1 Transverse section through the thoracic inlet
region of the thorax
Inferior view.
Brachiocephalic
trunk
Manubrium
Clavicle
Left brachiocephalic v.
Left common
carotid a.
First rib
Right brachiocephalic v.
Phrenic n.
Trachea
Left vagus n.
Esophagus
Left subclavian a.
Right lung,
superior lobe
Second rib
T3 vertebra
Sympathetic
trunk
Spinal cord
Left lung,
superior lobe
Third rib
Fig. 11.2 Transverse section through
the mid region of the thorax
Inferior view.
Right lung,
superior lobe
Internal thoracic
a. and v.
Sternum
Right
ventricle
Costomediastinal
recess
Interventricular
septum
Horizontal
fissure of right lung
Left
ventricle
Right
atrium
Left lung,
superior lobe
Right lung,
middle lobe
Phrenic n.
(between fibrous
pericardium and
parietal pleura,
mediastinal part)
Left
atrium
Oblique
fissure of
right lung
Oblique
fissure of
left lung
Esophagus
Thoracic
duct
Thoracic
(descending)
aorta
Azygos v.
Right lung,
inferior lobe
130
Left vagus n.
(anterior vagal trunk)
Sympathetic
trunks
Hemiazygos v.
Left lung,
inferior lobe
Superior
vena cava
Pulmonary
trunk
Ascending
aorta
Ascending
aorta
RA
Pulmonary
trunk
LV
A
Fig. 11.3 Coronal section through heart and
similar MRI
A
Image displays left ventricular outflow tract (LVOT) during
diastole.
B
Corresponding coronal (frontal) anatomical cross section of
the heart, anterior view.
Cardiac apex
RV
Interventricular
septum
LV
RA
Interatrial
septum
LA
Opening of
pulmonary
veins
A
Fig. 11.4 Transverse section through heart and
similar MRI
A
Image displays the atrioventricular connections of both
the right and left sides of the heart during diastole (fourchamber view).
B
Corresponding transverse anatomical cross section of the
heart, inferior view.
Lung
Right
atrium
(RA)
Liver
Aortic
valve
Left
ventricle
(LV)
Diaphragm
B
11 Sectional & Radiographic Anatomy
Superior
vena cava
Right
ventricle
(RV)
Tricuspid
valve
Interventricular septum
Right
atrium
(RA)
Left ventricle
(LV)
Mitral valve
Pulmonary
veins
Left atrium
(LA)
Esophagus
Ascending
aorta
B
Aortic arch
Pulmonary
trunk
LA
RV
Aortic valve
Infundibulum
of the RVOT
A
Fig. 11.5 Sagittal section of the heart and
similar MRI
A
Image displays the right ventricular outflow tract
(RVOT) during diastole.
B
Corresponding sagittal anatomical cross section of the
heart, viewed from the left side.
Pulmonary
trunk
Aortic
valve
Aortic
arch
Left main
bronchus
Left atrium
(LA)
Right
ventricle
(RV)
Pulmonary
veins
B
131
Thorax
Radiographic Anatomy of the Thorax (I)
Fig. 11.6
(Reproduced from Lange S.
Radiologische Diagnostik der
Thoraxerkrankungen, 4th ed.
Stuttgart: Thieme; 2010.)
Clavicle
Trachea
Sternum, manubrium
Aortic arch
Pulmonary a.
Superior vena cava
Auricle of left atrium
Lower lobe aa.
Left ventricle
Right atrium
Apex of heart
Dome of diaphragm
A
Posterior-anterior (PA) chest radiograph. Anterior view.
Trachea
Scapula
Aortic arch
Sternum
Retrosternal space
Left upper lobe bronchus
Right pulmonary a.
Left atrium
Retrocardiac space
Right ventricle
Left ventricle
Dome of diaphragm
B Left lateral chest radiograph.
132
Fig. 11.7 Left bronchogram
Anteroposterior view. (Reproduced from Moeller TB, Reif E. Pocket Atlas
of Radiographic Anatomy, 3rd ed. New York, NY: Thieme; 2010.)
Main bronchus
Anterior segment
of upper lobe
Lingula of the superior
segment of upper lobe
Lobar bronchus
Lingula of the inferior
segment of upper lobe
Segmental bronchus
Superior segment
of lower lobe
Posterior basal segment
of lower lobe
11 Sectional & Radiographic Anatomy
Apical-posterior segment
of upper lobe
Anterior-medial basal
segment of lower lobe
Lateral basal segment
of lower lobe
Fig. 11.8 MRI of the thorax
Coronal view. (Reproduced from Moeller TB, Reif E. Pocket Atlas of
Sectional Anatomy, Vol 2, 3rd ed. New York, NY: Thieme; 2007.)
Spinal cord
Right pulmonary a.
Right main bronchus
Left lung
Aortic arch
Left pulmonary a.
Right pulmonary v.
Left main bronchus
Left pulmonary v.
Right lung
Esophagus
Descending aorta
Spleen
Liver
Thoracic vertebrae, T11
Intervertebral disc T11–T12
133
Thorax
Radiographic Anatomy of the Thorax (II)
Fig. 11.9 Selective coronary angiography of the left coronary artery in a right anterior oblique position
Left coronary a.
Left interventricular a.
Left circumflex a.
Left diagonal aa.
Left marginal a.
Fig. 11.10 Selective coronary angiography of the right
coronary artery in a left anterior oblique projection
Left posterolateral a.
(Reproduced from Thelen M. et al. Bildgebene Kardiodiagnostik.
Stuttgart: Thieme; 2007.)
Right coronary a.
Right marginal a.
Fig. 11.11 CT of the heart
Right posterolateral a.
Posterior interventricular a.
CT angiography. (Reproduced from
Moeller TB, Reif E. Pocket Atlas of
Sectional Anatomy, Vol 2, 4th ed.
New York, NY: Thieme; 2014.)
Right auricle
Ascending aorta
Left atrium
Left pulmonary v.
Left coronary a. (LCA)
Right coronary a. (RCA)
Pulmonary trunk
Left auricle
Circumflex br. of LCA
Marginal br.
Anterior interventricular
br. of LCA
134
Fig. 11.12 MRI of the heart
(Reproduced from Moeller TB, Reif E. Pocket Atlas of Sectional
­Anatomy, Vol 2, 4th ed. New York, NY: Thieme; 2014.)
Branchiocephalic
trunk
Aortic valve
Right atrium
Left ventricle
Interventricular
septum
Right ventricle
Brachiocephalic
trunk
A
Left ventricular outflow tract.
Right
pulmonary vv.
Superior
vena cava
11 Sectional & Radiographic Anatomy
Pulmonary a.
Ascending aorta
Ascending
aorta
Pulmonary
trunk
Right atrium
Right atrioventricular
(tricuspid) valve
Right ventricle
B
Two chamber view
of right ventricle.
Fig. 11.13 Aortic arch angiogram
Left lateral view.
Right thyrocervical trunk
Right common carotid a.
Right vertebral a.
Right subclavian a.
Left thyrocervical trunk
Left vertebral a.
Left subclavian a.
Brachiocephalic trunk
Left common carotid a.
Aortic arch
Ascending aorta
Descending aorta
135
Thorax
Radiographic Anatomy of the Thorax (III)
Fig. 11.14 CT of the thorax
(Reproduced from Moeller TB, Reif E.
Pocket Atlas of Sectional Anatomy, Vol 2,
4th ed. New York, NY: Thieme; 2014.)
Pectoralis major
Rib
Sternum
Anterior edge of lung in
costomediastinal recess
A
B
C
Ascending aorta
Superior vena cava
Left lung
Right main bronchus
Left main bronchus
Descending aorta
Scapula
Subscapularis
Infraspinatus
A
Pulmonary trunk
Ascending aorta
Superior vena cava
Left pulmonary v.
Right pulmonary a.
Left atrium
Right inferior
lobar bronchus
Esophagus
Left inferior lobar bronchus
Azygos v.
Descending aorta
B
Conus arteriosus
Right auricle
Superior vena cava
Ascending aorta
Left ventricle
Left atrium
Left pulmonary v.
Esophagus
C
136
Descending aorta
Right atrium
Conus arteriosus
Left ventricle
Aortic valve
Left atrium
Right pulmonary v.
Left pulmonary v.
Esophagus
Descending aorta
11 Sectional & Radiographic Anatomy
D
E
F
D
Right ventricle
Interventricular septum
Right atrioventricular
(tricuspid) valve
Left ventricle
Right atrium
Left atrium
Esophagus
Descending aorta
Sympathetic trunk
E
Inferior vena cava
Esophagus
Azygos v.
Descending aorta
F
137
Abdomen
16 Neurovasculature
12 Surface Anatomy
Surface Anatomy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140
13 Abdominal Wall
Bony Framework for the Abdominal Wall . . . . . . . . . . . . . . .
Muscles of the Anterolateral Abdominal Wall . . . . . . . . . . . .
Rectus Sheath & Posterior Abdominal Wall . . . . . . . . . . . . . .
Abdominal Wall Muscle Facts . . . . . . . . . . . . . . . . . . . . . . . . .
Inguinal Region & Canal . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Inguinal Region & Inguinal Hernias. . . . . . . . . . . . . . . . . . . . .
Scrotum & Spermatic Cord . . . . . . . . . . . . . . . . . . . . . . . . . . .
142
144
146
148
150
152
154
14 Abdominal Cavity & Spaces
Divisions of the Abdominopelvic Cavity . . . . . . . . . . . . . . . .
Peritoneum, Mesenteries & Omenta . . . . . . . . . . . . . . . . . . .
Mesenteries & Peritoneal Recesses . . . . . . . . . . . . . . . . . . . .
Lesser Omentum & Omental Bursa . . . . . . . . . . . . . . . . . . . .
Mesenteries & Posterior Abdominal Wall. . . . . . . . . . . . . . . .
156
158
160
162
164
15 Internal Organs
Stomach . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Duodenum . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Jejunum & Ileum . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Cecum, Appendix & Colon . . . . . . . . . . . . . . . . . . . . . . . . . . .
Liver: Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Liver: Lobes & Segments . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Gallbladder & Bile Ducts . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Pancreas & Spleen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Kidneys & Suprarenal Glands (I) . . . . . . . . . . . . . . . . . . . . . . .
Kidneys & Suprarenal Glands (II) . . . . . . . . . . . . . . . . . . . . . .
166
168
170
172
174
176
178
180
182
184
Arteries of the Abdominal Wall & Organs . . . . . . . . . . . . . . .
Abdominal Aorta & Renal Arteries . . . . . . . . . . . . . . . . . . . . .
Celiac Trunk . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Superior & Inferior Mesenteric Arteries . . . . . . . . . . . . . . . . .
Veins of the Abdominal Wall & Organs . . . . . . . . . . . . . . . . .
Inferior Vena Cava & Renal Veins . . . . . . . . . . . . . . . . . . . . . .
Portal Vein . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Superior & Inferior Mesenteric Veins . . . . . . . . . . . . . . . . . . .
Lymphatics of the Abdominal Wall & Organs . . . . . . . . . . . .
Lymph Nodes of the Posterior Abdominal Wall . . . . . . . . . . .
Lymph Nodes of the Supracolic Organs . . . . . . . . . . . . . . . . .
Lymph Nodes of the Infracolic Organs . . . . . . . . . . . . . . . . . .
Nerves of the Abdominal Wall . . . . . . . . . . . . . . . . . . . . . . . .
Autonomic Innervation: Overview . . . . . . . . . . . . . . . . . . . . .
Autonomic Innervation & Referred Pain. . . . . . . . . . . . . . . . .
Innervation of the Foregut & Urinary Organs . . . . . . . . . . . .
Innervation of the Intestines . . . . . . . . . . . . . . . . . . . . . . . . .
186
188
190
192
194
196
198
200
202
204
206
208
210
212
214
216
218
17 Sectional & Radiographic Anatomy
Sectional Anatomy of the Abdomen . . . . . . . . . . . . . . . . . . . 220
Radiographic Anatomy of the Abdomen (I). . . . . . . . . . . . . . 222
Radiographic Anatomy of the Abdomen (II). . . . . . . . . . . . . . 224
12
Surface Anatomy
Abdomen
Surface Anatomy
Fig. 12.1 Palpable structures of the abdomen and pelvis
Anterior view. See pp. 2–3 for structures of the back.
Rectus
abdominis
Tendinous
intersections
Transumbilical
plane
(L3–4 disk)
Anterior superior
iliac spine (ASIS)
Linea alba
External
oblique
Semilunar
line
Anterior superior
iliac spine (ASIS)
Inguinal lig.
Pubic symphysis
Pubic tubercle
Superficial
inguinal ring
Sartorius
Quadriceps
femoris
Bony prominences.
A
Musculature.
B
Fig. 12.2 Quadrants and layers of the
abdominopelvic cavity
Anterior view. The location of the organs of the abdomen and pelvis
can be described by quadrant and layer.
Gallbladder
Right
upper
quadrant
(RUQ)
Right
lower
quadrant
(RLQ)
A
Quadrants, defined by the intersection of the median plane
and the transumbilical plane
through the L3–L4 disk.
Costal
margin
(arch)
Left upper
quadrant
(LUQ)
Spleen
Pancreas
Duodenum
Left lower
quadrant
(LLQ)
Descending
colon
Periumbilical
region
Ascending colon with cecum
and vermiform appendix
Suprarenal
glands
C
Organs of the
middle layer.
Liver
Stomach
Transverse
colon
Kidneys
Abdominal
aorta
Small intestine
( jejunum and
ileum)
B
Organs of the
anterior layer.
140
Ureters
Urinary
bladder
DOrgans of the
posterior layer.
Table 12.1
Transverse planes through the abdomen
Transverse plane midway between the superior
borders of the pubic symphysis and the
manubrium
② Subcostal plane
Plane at the lowest level of the costal margin (the
inferior margin of the tenth costal cartilage)
③ Supracrestal plane
Plane passing through the summits of the iliac
crests
④ Transtubercular plane
Plane at the level of the iliac tubercles (the iliac
tubercle lies ~5 cm posterolateral to the anterior
superior iliac spine)
⑤ Interspinous plane
Plane at the level of the anterior superior iliac spines
Superior border
of manubrium
12 Surface Anatomy
① Transpyloric plane
①
②
③
④
⑤
Superior border
of pubic
symphysis
Table 12.2
Regions of the abdomen
① Epigastric region
② Umbilical region
③ Pubic region
④ Left hypochondriac region
Midclavicular
line
Upper abdomen
⑤ Left lateral (lumbar) region
⑥ Left inguinal region
⑦
①
④
Costal margin
(arch)
Subcostal plane
Mid-abdomen
⑧
②
⑦ Right hypochondriac region
⑧ Right lateral (lumbar) region
⑨ Right inguinal region
⑤
Supracrestal plane
Lower abdomen
⑨
③
⑥
Iliac crest
Inguinal lig.
141
13
Abdominal Wall
Abdomen
Bony Framework for the Abdominal Wall
Fig. 13.1 Bony framework of the abdomen
Anterior view. These bones are the site of attachment
for the muscles and ligaments of the anterolateral
abdominal wall and form a bony cage that protects
certain abdominal organs.
4th rib
Body of
sternum
6th rib
Xiphoid
process
8th rib
T12
Costal
margin
L1
10th rib
L2
12th rib
Transverse
processes of
lumbar
vertebrae
L3
Wing (ala)
of ilium
L4
Iliac
tuberosity
L5
Iliac crest
Sacral
promontory
Anterior
superior
iliac spine
Arcuate
line
Iliopubic
eminence
Ischial
spine
Superior
pubic ramus
Pubic
tubercle
Anterior
superior
iliac spine
Sacrum
Fig 13.2 The inguinal ligament
Inguinal
lig.
Pubic
tubercle
142
Pubic
symphysis
Pubic
symphysis
Male pelvis, anterosuperior view.
The inguinal ligament is a palpable landmark
that forms the demarcation between the
abdominal wall and thigh. It is formed by the
inferior edge of the external oblique aponeurosis, the most superficial of the anterior
abdominal wall muscles. The inguinal ligament
attaches laterally to the anterior superior iliac
spine and medially to the pubic tubercle. It is
important clinically as it forms the floor of the
inguinal canal (see Table 13.2) and the roof of
the retro-inguinal space (see Fig. 34.31).
Fig. 13.3 Abdominal wall muscle attachment sites
Left hip bone. Muscle origins are in red, insertions in blue.
13 Abdominal Wall
Iliac crest
Quadratus
lumborum
Transversus
abdominis
Internal
oblique
External
oblique
Auricular surface
of ilium
Anterior superior
iliac spine
Psoas minor
Anterior inferior
iliac spine
Conjoint
tendon
Rectus abdominis,
lateral head
Arcuate line
Superior pubic
ramus
Pyramidalis
Quadratus
lumborum
Rectus sheath,
anterior layer
Transversus
abdominis
Rectus abdominis,
medial head
A
Superior view.
Posterior superior
iliac spine
Greater sciatic
notch
Psoas minor
Ischial spine
Superior pubic
ramus
Ischial tuberosity
B
Medial view.
143
Abdomen
Muscles of the Anterolateral Abdominal Wall
The muscles of the anterolateral abdominal wall consist of the external
and internal obliques and the transversus ­abdominis. The posterior or
deep abdominal wall muscles (notably the psoas major) are functionally
hip muscles (see p. 148).
Fig. 13.4 Muscles of the abdominal wall
Right side, anterior view.
Pectoralis major
(sternocostal
part)
Sternum
Serratus
anterior
Pectoralis major
(abdominal part)
Linea alba
External oblique
External oblique
aponeurosis
Rectus sheath,
anterior layer
Umbilicus
Internal
intercostals
Costal
cartilage
Sternum
External
intercostals
Xiphoid
process
Rectus
abdominis
Inguinal
lig.
Superficial
inguinal ring
External
oblique
Spermatic cord,
cremaster muscle
A
Superficial abdominal wall muscles.
Fundiform lig.
of the penis
Linea alba
Internal
oblique
Internal oblique
aponeurosis
Umbilicus
Anterior superior
iliac spine
Inguinal lig.
Rectus sheath,
anterior layer
Spermatic
cord,
cremaster
muscle
B
Removed: External oblique, pectoralis major, and serratus anterior.
144
13 Abdominal Wall
Sternum
Tendinous
intersections
Rectus
abdominis
External
oblique
Linea alba
Internal
oblique
Umbilicus
Transversus
abdominis
Inguinal
lig.
Transversus
abdominis
aponeurosis
Sternum
Pyramidalis
Rectus sheath,
posterior layer
Spermatic cord,
cremaster muscle
C
Removed: External and internal obliques.
External oblique
Linea alba
Internal oblique
Transversus
abdominis
Umbilicus
Semilunar
line
Arcuate
line
Rectus
abdominis
Transversalis
fascia
Inguinal lig.
Rectus sheath,
anterior layer
Deep
inguinal ring
Spermatic
cord
DRemoved: Rectus abdominis.
145
Abdomen
Rectus Sheath & Posterior Abdominal Wall
Fig. 13.5 The rectus sheath
The rectus sheath encloses the rectus abdominis and pyramidalis muscles on either side of
the midline. Its anterior and posterior layers
are formed by the aponeuroses of the anterolateral muscles as they split to pass around
the rectus muscles. An arcuate line marks the
inferior extent of the posterior layer, the point
at which all of the aponeuroses pass anterior
to the rectus muscles.
APosterior (interior) view of the anterior
abdominal wall. Peritoneum and transversalis fascia have been removed on
the left side to reveal the rectus sheath.
Parietal pleura,
diaphragmatic part
Central
tendon
Diaphragm
Costal part
of diaphragm
Linea alba
Parietal
peritoneum
Transversalis
fascia
External oblique
Plane of section
in figure B
Internal oblique
Rectus sheath,
posterior layer
Transversus
abdominis
Transversus
abdominis
Umbilicus
Arcuate line
Plane of section
in figure C
Iliacus
Rectus
abdominis
Iliopubic
tract
Rectus
abdominis
Rectus sheath,
anterior layer
Membranous layer,
subcutaneous tissue
Linea alba
External oblique
aponeurosis
External
oblique
Internal
oblique
Transversus
abdominis
Preperitoneal Parietal Transversalis
fat
peritoneum fascia
Rectus sheath,
Transversus
Internal
posterior layer
abdominis
oblique
aponeurosis aponeurosis
BSection through the abdominal wall
superior to the arcuate line.
Internal
oblique aponeurosis
External
oblique
aponeurosis
Transversus
abdominis
aponeurosis
Rectus sheath,
anterior layer
Linea alba
Transversalis
fascia
CSection through the abdominal wall
inferior to the arcuate line.
146
Skin
Fatty layer
Parietal
peritoneum
Membranous
layer
Subcutaneous
tissue
Fig. 13.6 Muscles of the posterior abdominal wall
Internal
intercostals
Transversus
thoracis
Caval opening
Central
tendon
Body of sternum
Diaphragm,
costal part
Aortic hiatus
T8 vertebral body
Esophageal
hiatus
T10 vertebral
body
T12 vertebral body
Costal arch
Transversus
abdominis
Rectus sheath,
posterior layer
Iliac crest
L5 vertebral body
13 Abdominal Wall
Manubrium
Caval opening
Esophageal
hiatus
Right crus
Median
arcuate lig.
Lateral arcuate
lig.
Medial arcuate
lig.
Quadratus
lumborum
Psoas minor
Central tendon
Diaphragm,
costal part
Diaphragm,
lumbar part,
and left crus
Aortic hiatus
Transversus
abdominis
Psoas major
Iliacus
Psoas major
Iliacus
Piriformis
Obturator
internus
Pubic symphysis
Sacrospinous
lig.
Iliopsoas
Gluteus
maximus
A
Midsagittal section with diagraphm in intermediate position.
B
Coronal section with diaphragm in intermediate position.
Central tendon
Inferior vena cava
Median arcuate
lig.
Right crus
Esophagus
Crural sling
Aorta
Left crus
Clinical box 13.1
Diaphragmatic hernias
C
Apertures of the diaphragm with vessels transected.
Anterior view.
The caval opening is located to the right of the midline,
those for the esophagus and aorta are to the left. Note that
the crura of the diaphragm typically extend inferiorly as far
as the L3 vertebra on the right and L2 vertebra on the left.
In diaphragmatic hernias, abdominal viscera prolapse into the thorax
through a congenital or acquired opening in the diaphragm. By far the
most common herniation site is the esophageal hiatus, accounting for
90% of cases. “Sliding” hernias, which account for 85% of these hiatal
hernias, occur when the distal end of the esophagus and the cardia of
the stomach slide upward into the thorax through the esophageal hiatus.
147
Abdomen
Abdominal Wall Muscle Facts
Fig. 13.7 Anterior abdominal
wall muscles
Anterior view.
Fig. 13.8 Anterolateral abdominal
wall muscles
Fig. 13.9 Posterior abdominal wall
muscles
Anterior view.
Anterior view. The psoas major and iliacus
are together known as the iliopsoas inferiorly.
⑧
D
A
G
F
Linea alba
⑦
⑥
S
A
External
oblique.
Table 13.1
B
Internal
oblique.
C
Transversus
abdominis.
Abdominal wall muscles
Muscle
Origin
Insertion
Innervation
Action
① Rectus abdominis
Lateral head: Crest of pubis to pubic
tubercle
Medial head: Anterior region of
pubic symphysis
Cartilages of 5th to 7th ribs,
xiphoid process of sternum
Intercostal nn. (T5–
Flexes trunk, compresses abdomen, stabilizes
T11) , subcostal n.
pelvis
(T12)
② Pyramidalis
Pubis (anterior to rectus
abdominis)
Linea alba (runs within the rectus
sheath)
Subcostal n. (T12)
Linea alba, pubic tubercle,
anterior iliac crest
Intercostal nn.
(T7–T11) ,
subcostal n. (T12)
Anterior abdominal wall muscles
Tenses linea alba
Anterolateral abdominal wall muscles
③ External oblique
5th to 12th ribs (outer surface)
④ Internal oblique
Thoracolumbar fascia (deep
layer), iliac crest (intermediate
line), anterior superior iliac spine,
iliopsoas fascia
⑤ Transversus
abdominis
7th to 12th costal cartilages (inner
surfaces), thoracolumbar fascia
(deep layer), iliac crest, anterior
superior iliac spine (inner lip),
iliopsoas fascia
10th to 12th ribs (lower borders),
linea alba (anterior and posterior
Intercostal
layers)
nn. (T7–T11) ,
subcostal n. (T12)
iliohypogastric n.,
ilioinguinal n.
Linea alba, pubic crest
Unilateral: Flexes trunk to same side, rotates
trunk to opposite side (external oblique) or
same side (internal oblique)
Bilateral: Flexes trunk, compresses abdomen,
stabilizes pelvis
Unilateral: Rotates trunk to same side
Bilateral: Compresses abdomen
Posterior abdominal wall muscles
Psoas minor*
(see Fig. 31.19)
⑥ Psoas
Superficial
layer
T12, L1 vertebrae and
intervertebral disk
(lateral surfaces)
T12–L4 vertebral bodies and
associated intervertebral disks
(lateral surfaces)
major
Deep layer
⑦ Iliacus
Iliac fossa
⑧ Quadratus
Iliac crest and iliolumbar lig. (not
shown)
lumborum
148
L1–L5 (costal processes)
Pectineal line, iliopubic ramus,
iliac fascia; lowermost fibers may
reach inguinal lig.
Weak flexor of the trunk
L1–L2 (L3) spinal
nn.
Femur (lesser trochanter), joint
insertion as iliopsoas muscle
Hip joint: Flexion and external rotation
Lumbar spine (with femur fixed):
Unilateral: Contraction flexes trunk laterally
Bilateral: Contraction raises trunk from supine
position
Femoral n. (L2–L4)
Unilateral: Flexes trunk to same side
12th rib, L1–L4 vertebrae (costal
processes)
* Approximately 50% of the population has this muscle. For the diaphragm see pp. 64–65.
Subcostal n. (T12),
L1–L4 spinal nn.
Bilateral: Bearing down and expiration,
stabilizes 12th rib
Fig. 13.10 Anterior, anterolateral, and posterior
abdominal wall muscles
5th rib
Anterior view.
External
oblique
5th rib
Linea alba
Xiphoid
process
External
oblique
aponeurosis
Umbilical
ring
13 Abdominal Wall
Xiphoid
process
Outer lip of
iliac crest
Linea
alba
Quadratus
lumborum
Superficial
inguinal
ring
Tendinous
intersections
Psoas major
Iliac crest
Anterior superior
iliac spine
Inguinal
lig.
B
External oblique.
Iliac fossa
Rectus
abdominis
Iliacus
Xiphoid
process
Inguinal
lig.
10th rib
Linea
alba
Internal oblique
aponeurosis
Iliopsoas
Internal oblique
Pubic
tubercle
Iliac crest,
intermediate line
Anterior superior
iliac spine
Lesser
trochanter
Pubic
symphysis
Inguinal lig.
Pyramidalis
A
Anterior and posterior muscles.
Pubic
symphysis
C
Internal oblique.
Fig. 13.11 Anterior and lateral abdominal
wall muscles as a functional unit
Sternum
Body of
sternum
Xiphoid
process
Linea alba
Linea alba
Rectus sheath,
posterior layer
Transversus
abdominis
Arcuate line
External
oblique
Rectus sheath,
anterior layer
Internal
oblique
Transversus
abdominis
Transversus abdominis
aponeurosis
Iliac crest
Anterior superior
iliac spine
Inguinal lig.
Pubic
symphysis
Rectus
abdominis
DTransversus abdominis.
149
Abdomen
Inguinal Region & Canal
The inguinal region is the junction of the
anterior abdominal wall and the anterior
thigh. The inguinal canal in the male is an
important site for the passage of structures
into and out of the abdominal cavity (e.g.,
components of the spermatic cord).
External
oblique
Internal
oblique
Transversus
abdominis
Rectus
abdominis
Linea alba
Fig. 13.12 Inguinal region
Rectus sheath
Right side, anterior view.
Iliopsoas
Membranous layer,
subcutaneous tissue
Femoral n.
Iliopectineal arch
External oblique
aponeurosis
Inguinal lig.
Ilioinguinal n.
Genitofemoral n.,
genital br.
Femoral a. and v.
Reflected
inguinal lig.
Spermatic cord
Lacunar lig.
Pubic tubercle
Superficial
inguinal ring
A
Male.
Lateral crus
Intercrural fibers
Medial crus
Cremaster m.
and cremasteric
fascia
Pectineus Plane of
section in
Table 13.2
External
spermatic
fascia
Superficial
inguinal ring
Lateral crus
External oblique
aponeurosis
Site of
inguinal lig.
Medial crus
Genitofemoral n.,
genital br.
A. of round lig.
V. of round lig.
B
Female.
150
Clinical box 13.2
Intercrural fibers
Fat pad
Ilioinguinal n.
Round lig.
of uterus
Gender differences of the inguinal canal
The inguinal canal is an oblique pathway
through the inferior part of the anterior
abdominal wall. In the male, it represents
the path through which the testis migrated
from the posterior abdominal wall into
the scrotum during the perinatal period.
It’s traversed by the spermatic cord (see
Table 13.4), which connects the testis
to the rest of the genitourinary system.
The female inguinal canal is smaller and
contains only the round ligament with
its neurovasculature. This ligament is
a remnant of the distal portion of the
embryonic gubernaculum, a structure
originally present in both males and
females but which regresses in the male
with descent of the testes.
Table 13.2
Structures of the inguinal canal
Structures
Formed by
Roof
Wall
Posterior wall
Floor
① External oblique aponeurosis
② Internal oblique m.
③ Transversus abdominis m.
④ Transversalis fascia
④
⑤
①
Iliopubic
tract
Pectineal
lig.
Lacunar
lig.
Superior
pubic ramus
⑤ Parietal peritoneum
⑥
Inguinal lig. (densely interwoven
fibers of the lower external oblique
aponeurosis and adjacent fascia lata
of the thigh)
Superficial
inguinal ring
Opening in external oblique
aponeurosis; bounded by medial and
lateral crus, intercrural fibers, and
reflected inguinal lig.
Deep inguinal ring
Outpouching of the transversalis
fascia lateral to the lateral umbilical
fold (inferior epigastric vessels)
Openings
Membranous
layer,
subcutaneous
tissue
Ilioinguinal n.
Spermatic cord
⑥
13 Abdominal Wall
Anterior wall
③
②
Pectineus
Fascia lata
Sagittal section through plane in Fig. 13.12A.
Fig. 13.13 Dissection of the male inguinal region
Right side, anterior view.
External
oblique
aponeurosis
Inguinal
lig.
Lateral crus
Intercrural
fibers
Location of deep
inguinal ring
Fig. 13.14 Opening of the inguinal canal
Right side, anterior view.
External
oblique
aponeurosis
Internal
oblique
Iliohypogastric n.,
anterior
cutaneous br.
Medial crus
Superficial
inguinal ring
Spermatic cord
Genitofemoral n.,
genital br.
Ilioinguinal n.
Superficial
inguinal ring
(cut open)
A
Superficial layer.
Spermatic cord with cremaster
m. and cremasteric fascia
Internal
oblique
A
Divided: External oblique aponeurosis.
Spermatic cord
with cremaster m.
B
Removed: External oblique aponeurosis.
Transversus
abdominis
Inguinal
lig.
Transversalis
fascia
Internal
oblique
Transversus
abdominis
Inferior epigastric
a. and v.,
interfoveolar
lig.
Deep
inguinal ring
Ilioinguinal n.
Rectus
abdominis
Spermatic cord
with internal
spermatic fascia
Hesselbach’s
triangle
Transversalis
fascia
Reflected
inguinal
lig.
Femoral
a. and v.
Spermatic cord, internal
spermatic fascia
B
Divided: Internal oblique and cremaster mm.
C
Removed: Internal oblique m.
151
Abdomen
Inguinal Region & Inguinal Hernias
Fig. 13.15 Sites of herniation
through the anterior abdominal
wall
Diaphragm
Coronal section, male, posterior
­(internal) view.
Parietal
peritoneum
AThe three fossae of the anterior
abdominal wall (circled) are sites
of potential herniation through
the wall.
Transversalis
fascia
Rectus sheath,
posterior layer
Arcuate line
Rectus abdominis
Inferior epigastric
a. and v.
Deep circumflex
iliac a. and v.
Falciform lig.
Round lig. of liver,
paraumbilical veins
Umbilicus
Median umbilical fold
Medial umbilical fold
Lateral umbilical fold
Lateral inguinal fossa
(deep inguinal ring)
Iliacus
Psoas major
External iliac a. and v.
Ductus deferens
Medial inguinal fossa
(Hesselbach‘s triangle)
Supravesical fossa
Bladder
Prostate
BInternal hernial openings in
the male inguinal region.
Detail from A. Peritoneum
and transversalis fascia
have been removed to
reveal the hernia openings.
Color shading indicates
openings for supravesical
(green), indirect (teal) and
direct (purple) hernias (see
Table 13.3).
Peritoneum
Transversalis
fascia
Arcuate line
Transversus
abdominis
Rectus abdominis
Inferior epigastric
a. and v.
Iliopubic tract
Femoral n.
Iliopsoas
Iliacus
Psoas major
Medial umbilical fold
Lateral inguinal fossa
(deep inguinal ring)
Interfoveolar lig.
Medial inguinal fossa
(Hesselbachʼs triangle)
Supravesical fossa
Iliopectineal arch
Testicular a. and v.
Femoral ring
External iliac a. and v.
Pectineal lig.
Ductus deferens
152
Right side, anterior view.
Transversalis
fascia
Deep inguinal ring
(lateral inguinal fossa)
Lateral umbilical fold
Transversus
abdominis
Medial inguinal fossa
(Hesselbach's triangle)
Internal
oblique
13 Abdominal Wall
Fig. 13.16 Schematic of the male
inguinal canal and its relation to
structures of the abdominal wall
Medial umbilical fold
(obliterated umbilical a.)
External oblique
aponeurosis
Superficial
investing fascia
Rectus abdominis
Subcutaneous tissue (fatty
and membranous layers)
Inferior epigastric
a. and v.
Superficial
inguinal ring
Scrotal skin with
dartos m. and fascia
Rectus sheath,
anterior layer
Cremaster m. and
cremasteric fascia
Pampiniform plexus, testicular a.
and ductus deferens
External spermatic
fascia
Internal spermatic
fascia
Epididymis
Testis
Scrotal cavity
Table 13.3
Hernias of the inguinal
region
Superficial inguinal ring
Most inguinal hernias occur in males. All are located above
the inguinal ligament and, if large enough, protrude
externally through the superficial ring. However, the
internal site of origin, and therefore structure of the hernia
sac (covering), differ among types. Femoral hernias, more
common in women, originate at the femoral ring below the
inguinal ligament and emerge at the saphenous opening in
the thigh.
Hernia type
Site of origin
Hernia sac
Indirect
inguinal
(congenital
or acquired)
Lateral inguinal fossa
(deep inguinal ring)
lateral to inferior
epigastric vessels
Peritoneum,
transversalis fascia,
cremaster m.
Direct
inguinal
(acquired)
Medial inguinal fossa
(Hesselbach’s triangle),
medial to inferior
epigastric vessels
Peritoneum,
transversalis fascia
Femoral
Femoral ring, inferior
to inguinal lig.
Cribiform fascia
of saphenous
opening
A Indirect inguinal hernia
B Direct inguinal hernia
153
Abdomen
Scrotum & Spermatic Cord
The coverings of the scrotum, testis, and spermatic
cord are continuations of muscular and fascial layers of the anterior abdominal wall, as are those of
the inguinal canal.
Fig. 13.17 Scrotum and spermatic cord
Anterior view.
Superficial
inguinal ring
Femoral
a. and v.
Spermatic
cord
Fundiform lig.
of the penis
Superficial penile
(Colles’) fascia
Root of the
penis
Scrotal
septum
External spermatic
fascia covering
spermatic cord
and testis
Dartos m.
and fascia
Scrotal skin
Gubernaculum
A
Structure and contents
of the scrotum.
Superficial
inguinal ring
Cremasteric fascia
and cremaster m.
External
spermatic fascia
Internal
spermatic fascia
Femoral a. and v.
Testicular plexus
Testicular a.
Pampiniform
plexus
(testicular vv.)
Epididymis
Tunica
vaginalis
Parietal layer
Ductus deferens
External
spermatic fascia
Processus
vaginalis
(obliterated)
Dartos m.
Visceral layer
Scrotum
B
Fascial and muscular layers of the spermatic
cord have been opened to reveal its contents.
154
Contents of the spermatic cord
Table 13.4
Contents
External spermatic fascia
① Ilioinguinal n.
Cremasteric muscle
② Cremasteric a. and v.
③ Genitofemoral n., genital br.
Internal spermatic fascia
④
⑧
⑨
⑥
④ A. and v. of ductus deferens
⑤ Ductus deferens
⑥ Testicular a.
⑦ Processus vaginalis (obliterated)
⑧ Testicular (nerve) plexus
⑨ Pampiniform (venous) plexus
Fig. 13.18 Testis and epididymis
⑦
①
⑤
③
External
spermatic fascia
Fibrous stroma
Cremasteric fascia
Cremaster m.
Internal
spermatic fascia
②
Skin
Left lateral view.
13 Abdominal Wall
Surrounding layer
Membranous layer,
subcutaneous tissue
Internal spermatic
fascia
External spermatic fascia
Cremasteric fascia and
cremaster m.
Testicular a.
Pampiniform plexus
Testicular plexus
Dartos fascia
Tunica vaginalis,
parietal layer
Epididymis, body
Epididymis,
head
Testis with tunica vaginalis,
visceral layer
Glans of penis
Scrotum
Table 13.5
Septum
6b
Cavity of
tunica
vaginalis
6a
Lobule
Covering layer
Scrotal septum
③
Mediastinum testis
with rete testis
④
Epididymis, head
Tunica
albuginea
Testicular a.
Ductus deferens
Transverse section through right testis, superior view.
⑤
Pampiniform plexus
Derived from
①
Scrotal skin
Abdominal skin
②
Dartos m. and fascia
Membranous layer,
subcutaneous tissue
③
External spermatic
fascia
External oblique
aponeurosis and superficial
investing fascia
④
Cremaster m.
and cremasteric fascia
Internal oblique m.
⑤
Internal spermatic
fascia
Transversalis
fascia
6a
Tunica vaginalis,
parietal layer
6b
Tunica vaginalis,
visceral layer
①
②
Coverings of the testis
Peritoneum
* The transversus abdominis has no contribution to the
spermatic cord or covering of the testis.
155
14
Abdominal Cavity & Spaces
Abdomen
Divisions of the Abdominopelvic Cavity
Fig. 14.1 Organs of the
abdominopelvic cavity
Midsagittal section, male, viewed from the left.
Sternum
Liver
Esophagus
Liver, bare area
Omental foramen
Hepatogastric lig.
(lesser omentum)
Omental bursa
(lesser sac)
Pancreas, neck
Stomach
Middle colic a.
Transverse
mesocolon
Celiac trunk
Splenic a. and v.
Left renal a.
Superior
mesenteric a.
Left renal v.
Pancreas,
uncinate process
Abdominal aorta
Transverse
colon
Duodenum,
horizontal part
Greater omentum
Mesentery
Jejunum
and ileum
L5 vertebra
Rectus abdominis
Urinary bladder
Ductus deferens,
ampulla
Bulbospongiosus
Left common iliac
a. and v.
Rectovesical
pouch
Rectum
Prostate
Deep transverse
perineal
Scrotum,
septum
Clinical box 14.1
Acute abdominal pain
Acute abdominal pain (“acute abdomen”) may be so severe that the
abdominal wall becomes extremely sensitive to touch (“guarding”) and
the intestines stop functioning. Causes include organ inflammation such
156
as appendicitis, perforation due to a gastric ulcer (see p. 167), or organ
blockage by a stone, tumor, etc. In women, gynecological processes or
ectopic pregnancies may produce severe abdominal pain.
Fig. 14.2 Divisions of the pelvic and
abdominal cavities
14 Abdominal Cavity & Spaces
Each column of diagrams shows a midsagittal section viewed from
the left side, as well as two axial sections, one at the L1 level and the
other at the lower part of the sacrum, both viewed from below.
Omental
bursa
Linea
terminalis
Rectovesical
pouch
A
D
G
B
E
C
F
A–C Topography of body cavities:
abdominal cavity and pelvic cavity
(imaginary line separating the two
cavities is the linea terminalis).
Omental
bursa
Rectovesical
pouch
D–F Serous cavities (peritoneal spaces):
abdominal peritoneal cavity and
pelvic peritoneal cavity.
H
I
Retroperitoneal
space
Subperitoneal
space
G–I Connective tissue spaces (extraperitoneal spaces): retroperitoneal space and
subperitoneal space; serous cavities
and extraperitoneal spaces are separated by peritoneum.
157
Abdomen
Peritoneum, Mesenteries & Omenta
Organs in the abdominopelvic cavity are classified by the presence of
surrounding peritoneum (the serous membrane lining the cavity) and
a mesentery (a double layer of peritoneum that connects the organ to
the abdominal wall) (see Table 14.1).
Fig. 14.3 Peritoneal cavity
Bare area of
the liver
Lesser
omentum
Omental bursa
Parietal
peritoneum
Transverse
mesocolon
Mesentery (of the
small intestine)
Parietal
peritoneum
Greater
omentum
Visceral
peritoneum
Rectovesical
space
A
Midsagittal section through the male abdominopelvic cavity, viewed from the left.
The peritoneum is shown in red.
Clinical box 14.2
Peritonitis and ascites
Bacterial contamination of the perito­neum following surgery or rupture of
an inflamed organ (duode­num, gallbladder, appendix) results in peritonitis,
inflammation of the peritoneum. It is accompanied by severe abdominal
pain, tenderness, nausea, and fever and can be fatal when generalized
throughout the peritoneal cavity. It often results in ascites, the accumulation
of excess peritoneal fluid due to a change in concen­tration gradients that
158
results in loss of capillary fluid. Ascites can also accompany other pathologic
conditions, such as metastatic liver cancer and portal hypertension. In these
cases, many liters of ascitic fluid can accumulate in the peritoneal cavity. The
fluid is aspirated by paracentesis. The needle is carefully inserted through
the abdominal wall so as to avoid the urinary bladder and inferior epigastric
vessels.
Fig. 14.5 Relationship of an intraperitoneal
organ to the mesentery and peritoneum
Arrows indicate blood vessels in the mesentery.
Transverse section, superior view (See Table 14.2).
Mesentery
Intraperitoneal organ
(e.g., jejunum)
Parietal
peritoneum
Visceral
peritoneum
Parietal
layer
Mesentery
Peritoneal
cavity
Secondarily
retroperitoneal
organ (e.g.,
ascending colon)
Extraperitoneal
or primarily
retroperitoneal
organ (e.g., kidney)
Abdominal
aorta
Visceral
layer
Peritoneum
Retroperitoneal
space
Intraperitoneal
organ
Lumbar
spine
Fig. 14.6 Structure of the greater and
lesser omenta and their relation to the
omental bursa
Liver
Lesser omentum
Omental bursa
Pancreas
Stomach
Duodenum
Gastrocolic
lig.
Transverse mesocolon
Transverse colon
Mesentery (of the
small intestine)
Greater omentum
Mesenteries and omenta
Table 14.1
Sagittal section, left lateral view.
Table 14.2
Peritoneal
cavity
14 Abdominal Cavity & Spaces
Fig. 14.4 Schematic showing peritoneal relations
of intraperitoneal and extraperitoneal (primary
and secondary retroperitoneal) organs of the
abdomen
Mesenteries
Mesentery (of the small intestine)
Transverse mesocolon
Sigmoid mesocolon
Mesoappendix
Omenta
Lesser omentum
Greater omentum
Reflections of the peritoneum that connect organs to the body wall or to
another organ allow normal mobility of the gastrointestinal tract while
preventing excessive movement. A mesentery is a double layer of peritoneum
that connects intraperitoneal organs to the posterior abdominal wall and
transmits nerves and vessels. An omentum is a double layer of peritoneum
that connects the stomach and duodenum to another organ or to the
posterior abdominal wall.
Organs of the abdominopelvic cavity classified by their relationship to the peritoneum
Location
Organs
Intraperitoneal organs: These organs have a mesentery and are completely covered by the peritoneum.
Abdominal peritoneal
• Stomach
• Gallbladder
• Small intestine (jejunum, ileum, some of
• Cecum with vermiform appendix (portions of variable
the superior part of the duodenum) size may be retroperitoneal)
• Spleen
• Large intestine (transverse and sigmoid colons)
• Liver
Pelvic peritoneal
• Uterus (fundus and body)
• Ovaries
• Uterine tubes
Extraperitoneal organs: These organs either have no mesentery or lost it during development.
Retroperitoneal
Primarily
• Kidneys and ureters
Secondarily
• Duodenum (descending, horizontal, and ascending)
• Pancreas
Infraperitoneal/subperitoneal
• Urinary bladder
• Distal ureters
• Prostate
• Suprarenal glands
• Seminal glands
• Uterine cervix
• Uterine cervix
• Ascending and descending colon and cecum
• Rectum (upper 2/3)
• Vagina
• Rectum (lower 1/3)
159
Abdomen
Mesenteries & Peritoneal Recesses
The peritoneal cavity is divided into the large greater sac and small
omental bursa (lesser sac). The greater omentum is an apron-like fold
of peri­toneum suspended from the greater curvature of the stomach
and covering the anterior surface of the transverse colon. The attach-
ment of the transverse mesocolon on the anterior surface of the descending part of the duodenum and the pancreas divides the peritoneal
cavity into a supracolic compartment (liver, gallbladder, and stomach)
and an infracolic compartment (intestines).
Fig. 14.7 Dissection of the peritoneal
cavity
Falciform
lig. of liver
Liver, left lobe
Round lig.
of liver
Anterior view.
Stomach
Liver, right lobe
Left colic flexure
Gallbladder
Transverse
colon
Ascending
colon
Greater omentum
Tenia coli
Ileum
Lateral umbilical fold
(with inferior epigastric
a. and v.)
Rectus
abdominis
Medial umbilical fold
(with obliterated
umbilical a.)
Arcuate
Median umbilical fold
line
(with obliterated urachus)
A
Greater sac. Retracted: Abdominal wall.
Greater omentum
(reflected superiorly)
Transverse
colon
Transverse
mesocolon
with middle
colic a. and v.
Ascending
colon
Tenia coli
Ileum
B
Infracolic compartment, the portion of the
peritoneal cavity below the attachment of
the transverse mesocolon. Reflected: Greater
omentum and transverse colon.
160
Parietal
peritoneum
Jejunum
(covered by
visceral peritoneum)
CMesentery (of the small intestine). Reflected: Greater omentum,
transverse colon, small intestine.
14 Abdominal Cavity & Spaces
Greater
omentum
Transverse
colon
Root of
mesentery
Convoluted
small
intestine
Ascending
colon
Superior
iliocecal recess
Cecum
Greater omentum
(reflected superiorly)
Left colic flexure
Superior duodenal
recess
Mesentery,
root
Inferior duodenal
recess
Descending colon
Sigmoid colon
Sigmoid mesocolon
Inferior
iliocecal
recess
Mesoappendix
Intersigmoidal recess
Appendix
Retrocecal recess
DMesenteries and mesenteric recesses in the
infracolic compartment. Reflected: Greater
omentum, transverse colon, small intestines,
and sigmoid colon.
161
Abdomen
Lesser Omentum & Omental Bursa
The omental bursa, or lesser sac, is the portion of the peritoneal cavity behind the stomach and the lesser omentum (a double-layered
peritoneal structure connecting the lesser curvature of the stomach
Fig. 14.8 The lesser
omentum
and the proximal part of the duodenum to the liver). The omental bursa
communicates with the greater sac via the omental (epiploic) foramen,
located posterior to the free edge of the lesser omentum.
Stomach
Gallbladder
Anterior view with liver
retracted superiorly.
The arrow points to the
omental foramen, the
opening into the omental
bursa, posterior to the
lesser omentum.
Diaphragm
Hepatogastric lig.
Hepatoduodenal
lig.
Lesser
omentum
Duodenum
Greater
omentum
Fig. 14.9 Omental bursa in situ
Anterior view. Divided: Gastrocolic ligament.
Retracted: Liver. Reflected: Stomach.
Gallbladder
Vestibule of
omental bursa
Omental foramen
Common
hepatic a.
Liver,
right lobe
Duodenum,
descending part
Right kidney
Right colic flexure
Ascending colon
Greater
omentum
162
Stomach,
greater curvature
Gastrocolic lig.
Stomach,
posterior surface
Gastrosplenic lig.
Left gastric a.
Left suprarenal
gland
Left kidney,
superior pole
Splenic a.
Spleen
Celiac trunk
Phrenicocolic lig.
Pancreas
Transverse
mesocolon
Middle colic a.
and v.
Gastrocolic lig.
Transverse colon
Descending colon
Fig. 14.10 Location of the omental bursa
Liver
Transverse section, inferior view.
Pancreas
Omental bursa
14 Abdominal Cavity & Spaces
Stomach
Splenic recess
of omental bursa
Spleen
Inferior Abdominal Left
vena cava
aorta
kidney
Fig. 14.11 Boundaries and walls of the omental bursa
(lesser sac)
Anterior view.
Liver, caudate
lobe
Gallbladder
Hepatoduodenal
lig. (lesser
omentum)
Liver, right lobe
Liver, left lobe
Cardiac
orifice
Spleen
Duodenum
Pancreas
Greater
omentum
Gastrocolic lig.
(cut)
Diaphragm,
hepatic surface
Inferior
vena cava
Transverse
colon
Splenic recess of
omental bursa
Superior recess of
omental bursa
Duodenum
Inferior recess of
omental bursa
Transverse
mesocolon
A
Boundaries of the omental bursa (lesser sac).
Table 14.3
Vestibule of
omental bursa
Diaphragm
Pancreas
Hepatoduodenal lig.
(lesser omentum, cut)
B
Posterior wall of the omental bursa (lesser sac).
Boundaries of the omental bursa
Direction
Boundary
Recess
Anterior
Lesser omentum, gastrocolic lig.
—
Inferior
Transverse mesocolon
Inferior recess
Superior
Liver (with caudate lobe)
Superior recess
Posterior
Pancreas, aorta (abdominal part), celiac
trunk, splenic a. and v., gastrosplenic
fold, left suprarenal gland, left kidney
(superior pole)
—
Liver, duodenal bulb
—
Posterior
Inferior vena cava, diaphragm (right crus)
Splenic recess
Superior
Liver (caudate lobe)
Right
Left
Spleen
Spleen, gastrosplenic lig.
Table 14.4
Boundaries of the omental foramen
The communication between the greater sac and lesser sac (omental bursa) is
the omental (epiploic) foramen (see arrow in Fig. 14.9).
Direction
Boundary
Anterior
Hepatoduodenal lig. with the portal v., proper hepatic a., and
bile duct
Inferior
Duodenum (superior part)
163
Abdomen
Mesenteries & Posterior Abdominal Wall
Fig. 14.12 Mesenteric attachments of
intraperitoneal organs
Anterior view. Removed: Stomach, jejunum and ileum, and transverse
and sigmoid colons. Retracted: Liver.
Liver,
right lobe
Round lig.
of liver
Hepatogastric
lig. (lesser
Liver,
omentum, cut) left lobe
Cardiac
orifice
Superior
border
Spleen
Gastric
surface
Gallbladder
Hepatoduodenal
lig. (lesser
omentum)
Omental foramen
Gastrosplenic lig.
Pancreas
Duodenum,
superior part
Stomach, pyloric part
Transverse
mesocolon, root
Left colic flexure
Greater omentum (cut)
Transverse colon
Right colic flexure
Duodenojejunal
flexure
Transverse colon
Duodenum,
horizontal part
Mesentery
(cut)
Descending colon
Tenia coli
Transversus abdominis,
internal and external
oblique
Ascending colon
Terminal ileum
Sigmoid mesocolon
(cut)
Cecum
Rectum
Lateral umbilical fold
(with inferior epigastric
a. and v.)
Rectus abdominis
Medial umbilical fold
(with obliterated
umbilical a.)
Median
umbilical fold
(with obliterated
urachus)
Transverse
mesocolon
L4
Mesentery
Sigmoid
mesocolon
Fig. 14.13 Location of mesenteric sites
of connection to the abdominal wall
164
Fig. 14.14 Posterior wall of the
peritoneal cavity
Parietal
Diaphragm, Hepatic Inferior Cardiac orifice
peritoneum hepatic surface vv. vena cava of stomach
Left suprarenal
gland
Gastrosplenic
lig.
Splenic a. and v.
Hepatoduodenal
lig. (with portal
v., hepatic a.,
and bile duct)
Right kidney
Pancreas,
body and tail
Left kidney
Superior
part
Descending
part
Pancreas, head
Duodenum
Left colic a. and v.
Descending colon
(site of attachment)
Superior mesenteric
a. and v.
Inferior mesenteric a.
Horizontal
part
Ascending
part
Abdominal aorta
Duodenum
14 Abdominal Cavity & Spaces
Right suprarenal
gland
Anterior view. Removed: All intraperitoneal
organs. Revealed: Structures of the retroperitoneum (see Table 14.2 and p. 250).
Transversus abdominis,
internal and external
oblique
Paracolic gutter
Parietal
peritoneum
Mesenteric root
Right common iliac
a. and v.
Ascending colon
(site of attachment)
Mesoappendix
Sigmoid
mesocolon
Left ureter
Right ureter
External iliac a.
Rectum
Fig. 14.15 Drainage spaces and recesses within
the peritoneal cavity
Anterior view.
Subhepatic
recess
Subphrenic
recess
Hepatic surface
of diaphragm
Left paracolic
gutter
Inferior
vena cava
Transverse
mesocolon (root)
Hepatoduodenal
ligament
Spleen
Right kidney
Left kidney
Duodenum
Hepatorenal
recess
Superior
duodenal recess
Site of
attachment of
ascending colon
Inferior
duodenal recess
Mesentery (root)
Right
paracolic
gutter
Site of attachment
of descending colon
Superior
ileocecal recess
Left paracolic gutter
Sigmoid
mesocolon
(root)
Inferior
ileocecal recess
Right infracolic
space
Left infracolic
space
A
Anterior view with the greater omentum and small intestine removed; preferred metastatic sites (see blue stars).
Retrocecal
recess
Rectovesical
pouch
Intersigmoid
recess
B
Posterior wall of the peritoneal cavity, anterior view. The mesenteric roots and
sites of organ attachment create partially bounded spaces (recesses or sulci)
where peritoneal fluid can flow freely.
165
15
Internal Organs
Abdomen
Stomach
Fig. 15.1 Stomach: Location
RUQ
LUQ
Fig. 15.2 Relations of the stomach
Lesser omentum
(hepatogastric
lig.)
Stomach
Pancreas
Transpyloric
plane
Omental bursa
Liver
A
Anterior view.
Left
kidney
Phrenic
surface
Suprarenal
surface
Splenic surface
Renal surface
Fundus
Anterior view.
Phrenic
surface
Epigastric
surface
B
Transverse section, inferior view.
Fig. 15.3 Stomach
Hepatic
surface
Spleen
Inferior Abdominal
vena cava
aorta
A
Anterior view.
Esophagus
Pancreatic
surface
Esophagus
Colomesocolic
surface
Cardia
B
Posterior view.
Lesser
curvature
Duodenum
Hepatic
surface
Greater
curvature
Pyloric Angular
canal notch
Body
Endoscopic
light source
Fundus
Esophagus,
adventitia
Esophagus,
muscular coat,
longitudinal layer
Pyloric antrum
A
Anterior wall.
Esophagus
Duodenum,
superior part
Pyloric
sphincter
Cardia
Outer longitudinal layer
Middle circular
layer
Inner oblique layer
Duodenum
Pyloric
sphincter
Angular
notch
Pyloric
orifice
C
Interior. Removed: Anterior wall.
166
Body with
longitudinal
rugal folds
Muscular
coat
Rugal folds
B
Muscular layers. Removed: Serosa and
subserosa. Windowed: Muscular coat.
The stomach, an intraperitoneal organ, resides primarily in the left
­upper quadrant. Double layers of peritoneum extend superiorly from its
Anterior view of the opened
upper abdomen. Arrow indicates the omental foramen.
Liver,
right lobe
Falciform lig.
of liver
Liver,
left lobe
Esophagus
Parietal
peritoneum
Diaphragm
Stomach,
fundus
Stomach,
cardia
Hepatoesophageal
lig.
Gallbladder
Hepatoduodenal
lig.
15 Internal Organs
Fig. 15.4 Stomach in situ
Round lig.
of liver
lesser curvature as the lesser omentum and inferiorly from its greater
curvature as the greater omentum.
Stomach,
body
Lesser
omentum
Spleen
Lesser
curvature
Hepatogastric
lig.
Right kidney
Greater
curvature
Right colic
flexure
Descending
colon
Transversus
abdominis,
internal and
external
oblique
Ascending
colon
Duodenum
Pyloric canal
Pyloric antrum
Greater omentum
Clinical box 15.1
Gastritis and gastric ulcers
Gastritis and gastric ulcers, the two most common diseases of the stomach,
are associated with increased acid production and are caused by alcohol,
drugs such as aspirin, and the bacterium Helicobacter pylori. Symptoms
include lessened appetite, pain, and even bleeding, which manifests as
black stool or dark brown material, often described as resembling “coffee
grounds,” in vomit. Gastritis is limited to the inner surface of the stomach,
whereas gastric ulcers extend into the stomach wall. In these endoscopic
images, the gastric ulcer in C is covered with fibrin and shows hematin spots.
Gastric
ulcer
Gastric
antrum
Rugal
folds
A
Body of normal stomach.
B
Normal pyloric antrum.
C
Gastric ulcer.
167
Abdomen
Duodenum
The small intestine consists of the duodenum, jejunum, and ileum. The
duodenum is primarily retroperitoneal and is divided into four parts:
superior, descending, horizontal, and ascending.
Fig. 15.6 Parts of the duodenum
Fig. 15.5 Duodenum: Location
Anterior view.
Anterior view.
RUQ
LUQ
Esophagus
Inferior
vena cava
Diaphragm,
right crus
Duodenal bulb
Superior
(1st) part
Duodenojejunal
flexure
Duodenum
Diaphragm,
left crus
Celiac trunk
Superior
duodenal flexure
Jejunum
and ileum
Suspensory
lig. of
duodenum
Descending
(2nd) part
Superior
mesenteric a.
Jejunum
Inferior
duodenal flexure
Ascending
(4th) part
Horizontal (3rd) part
Fig. 15.7 Duodenum
Anterior view with the anterior wall opened.
Pyloric
orifice
Bile duct
Pyloric
sphincter
Duodenum,
superior part
Circular folds
(valves of Kerckring)
Accessory
pancreatic duct
Pancreas
Minor
duodenal papilla
Duodenum,
descending part
Duodenojejunal
flexure
Main pancreatic
duct
Major
duodenal papilla
Muscular
coat
168
Superior
mesenteric a. and v.
Longitudinal
layer
Circular
layer
Jejunum
Submucosa
Duodenum,
horizontal part
Fig. 15.8 Duodenum in situ
Parietal
peritoneum
Inferior
vena cava
Hepatic vv.
Common
hepatic a.
Esophagus
Phrenicosplenic
lig.
Diaphragm
Spleen
Left gastric a.
Hepatic surface
of diaphragm
Hepatoduodenal
lig. (with
portal triad)
Left suprarenal
gland
Right suprarenal
gland
Abdominal
aorta
Pancreas
15 Internal Organs
Anterior view. Removed: Stomach, liver, small intestine, and large
­portions of the transverse colon. Thinned: Retroperitoneal fat and
­connective tissue.
Splenic a.
Right kidney
Left colic flexure
Duodenum,
superior part
Left kidney
Superior duodenal
recess
Right colic flexure
Jejunum
Transverse colon
Superior mesenteric
a. and v.
Ascending colon
Descending colon
Inferior duodenal
recess
Duodenum,
descending part
Right
colic a.
Root of
mesentery
Duodenum,
horizontal part
Duodenum,
ascending part
Left colic
a. and v.
Clinical box 15.2
Endoscopy of the papillary region
Two important ducts end at a common exit site in the descending portion
of the duodenum: the common bile duct and the pancreatic duct (see
Fig. 15.27). These ducts may be examined by X-ray through endoscopic
retrograde cholangiopancreatography (ERCP), in which dye is injected
endoscopically into the duodenal papilla. Duodenal diverticula (generally
harmless outpouchings) may complicate the procedure.
Stomach
Circular
folds
Duodenal
papilla
A
Endoscopic
appearance.
Duodenal
diverticula
B
Radiograph.
169
Abdomen
Jejunum & Ileum
Fig. 15.9 Jejunum and ileum: Location
Anterior view. The intraperitoneal jejunum and ileum are enclosed
by the mesentery proper.
RUQ
Fig. 15.10 Mucosal appearance of the jejunum and ileum
Macroscopic views of the longitudinally opened small intestine.
Lymphatic
follicles
(Peyer’s
patches)
LUQ
Duodenojejunal flexure
Circular
folds
Jejunum
and ileum
RLQ
LLQ
Rectum
Fig. 15.11 Jejunum and ileum in situ
Anterior view. Reflected: Transverse colon.
A
Jejunum.
Greater omentum
Epiploic
(reflected superiorly) appendices
B
Ileum.
Tenia coli
Transverse
colon
Round
lig. of liver
Transverse
mesocolon (with
middle colic
a. and v.)
Jejunum
Ascending
colon
Tenia coli
Transversus abdominis,
internal and external
oblique
Cecum
Ileum
Lateral umbilical
fold (with inferior
epigastric a. and v.)
Rectus
abdominis
Medial umbilical fold
(with obliterated
umbilical a.)
Median umbilical fold
Arcuate
(with obliterated urachus)
line
170
Clinical box 15.3
15 Internal Organs
Crohn’s disease
Crohn’s disease, a chronic inflammation of the
digestive tract, occurs most often in the terminal
ileum (30% of cases). Patients are generally young
and suffer from abdominal pain, nausea, elevated
body temperature, and diarrhea. Initially, these
symptoms can be confused with appendicitis.
Complications of the chronic inflammation in Crohn’s
disease often lead to fistula formation (seen here
in figure B as an abnormal passage between two
gastrointestinal regions).
A MRI showing thickened wall of terminal
ileum. (arrow).
Fig. 15.12 Mesentery of
the small intestine
Liver,
right lobe
Anterior view. Removed: Stomach,
jejunum, and ileum. Reflected: Liver.
Round
lig. of liver
Hepatogastric
lig.
B
Double-contrast radiograph, showing ileorectal fistula (arrow).
Liver,
left lobe
Esophagus
Gallbladder
Lesser omentum,
hepatoduodenal
lig.
Omental foramen
Duodenum,
superior part
Spleen
Gastrosplenic lig.
Pancreas
Transverse mesocolon,
root
Stomach, pyloric part
Left colic flexure
Greater omentum
Transverse colon
Right colic flexure
Duodenojejunal
flexure
Transverse colon
Duodenum,
horizontal part
Mesentery
(cut edge)
Descending colon
Tenia coli
Ascending colon
Terminal ileum
Cecum
Sigmoid mesocolon
(cut edge)
Rectum
171
Abdomen
Cecum, Appendix & Colon
The ascending and descending colon are normally secondarily retroperitoneal, but are sometimes suspended by a short mesentery from
the posterior abdominal wall. Note: In the clinical setting, the left colic
flexure is often referred to as the splenic flexure and the right colic
flexure, as the hepatic flexure.
Fig. 15.13 Large intestine:
Location
RUQ
Fig. 15.14 Ileocecal orifice
Anterior view of longitudinal coronal section.
LUQ
Anterior view.
Left colic
flexure
Right
colic flexure
Transverse
colon
Ascending
colon
Inner
circular layer
Outer
longitudinal layer
Ascending
colon
Ileal
papilla,
ileocolic
labrum
Descending
colon
Superior lip
Inferior lip
Sigmoid
colon
Cecum
RLQ
Rectum
Fig. 15.15 Large intestine
Ileocecal orifice
LLQ
Greater omentum
(cut)
Anterior view.
Haustra
Left colic (splenic)
flexure
Transverse
mesocolon
Right
colic (hepatic)
flexure
Descending
colon
Tenia coli
Ascending
colon
Transverse
colon
Mesentery (with
anterior cecal a.)
Ileocecal orifice
Ileum, terminal
part
Tenia coli
Tenia coli
Haustra
Tenia coli
Sigmoid
mesocolon
Semilunar
folds
Iliocecal labrum,
superior and
inferior lips
Cecum
Epiploic
appendices
Vermiform
appendix
(with
orifice) Mesoappendix
(with
appendicular a.)
Rectum (with
peritoneal reflection)
172
Muscular
coat
Sigmoid
colon
Fig. 15.16 Large intestine in situ
Anterior view. Reflected: Transverse colon and greater
omentum. Removed: Intraperitoneal small intestine.
Transverse
colon
Left colic
(splenic)
flexure
Transverse
mesocolon
15 Internal Organs
Greater
omentum
Duodenojejunal
flexure
Right
colic (hepatic)
flexure
Descending
colon
Mesentery
(cut)
Sigmoid
mesocolon
Ascending
colon
Sigmoid
colon
Terminal
ileum
Cecum
Rectum
Rectus
abdominis
Clinical box 15.4
Clinical box 15.5
Colitis
Ulcerative colitis is a chronic inflammation of the large intestine, often
starting in the rectum. Typical symptoms include diarrhea (sometimes
with blood), pain, weight loss, and inflammation of other organs.
Patients are also at higher risk for colorectal carcinomas.
A C
olonoscopy of ulcerative
colitis.
B
Early-phase colitis. Doublecontrast radiograph, anterior
view.
Colon carcinoma
Malignant tumors of the colon and rectum are among the most frequent
solid tumors. More than 90% occur in patients over the age of 50. In
early stages, the tumor may be asymptomatic; later symptoms include
loss of appetite, changes in bowel movements, and weight loss. Blood
in the stools is particularly incriminating, necessitating a thorough
examination. Hemorrhoids are not a sufficient explanation for blood in
stools unless all other tests (including a colonoscopy) are negative.
Colonoscopy of colon carcinoma.
The tumor (black arrows) partially
blocks the ­lumen of the colon.
173
Abdomen
Liver: Overview
Fig. 15.17 Liver: Location
Spleen
RUQ
LUQ
Stomach
Liver
Spleen
Duodenum
Transverse
colon
Descending
colon
Ascending
colon
Small
intestine
LUQ
RUQ
Left kidney
and suprarenal gland
Liver
Right kidney and
suprarenal gland
Pancreas
Ascending
colon
Posterior view.
B
A
Anterior view.
Fig. 15.18 Relations of the liver
Lesser
omentum
Visceral (inferior) surface, inferior view.
Stomach
Pancreas
Omental bursa,
vestibule
Omental bursa,
splenic recess
Liver
Suprarenal
impression
Spleen
Renal
impression
Inferior
Abdominal
vena cava
aorta
Left
kidney
Transverse section, inferior view.
C
Gastric
impression
Fig. 15.19 Liver in situ
Diaphragmatic
pleura
Anterior view. The liver is intraperitoneal
except for its “bare area” (see Fig. 15.21); its
mesenteries include the falciform, coronary,
and triangular ligaments (see Fig. 15.22).
Diaphragm
Esophagus
Duodenal
impression
Aorta
Colic
impression
Fibrous
pericardium
Mediastinal
pleura
Falciform lig.
Liver,
right lobe
Liver,
left lobe
Stomach
Gallbladder
174
Round
lig. of
liver
Transversus
abdominis,
internal and
external oblique
Transverse
colon
Ascending
colon
Greater
omentum
Fig. 15.20 Liver in situ: Inferior surface
The liver is retracted to show the gallbladder on
its inferior surface.
Liver,
right lobe
Falciform lig.
of liver
Liver,
left lobe
Lesser
omentum
Hepatoduodenal
lig.
Stomach,
body
15 Internal Organs
Gallbladder
Hepatogastric
lig.
Right kidney
Right colic
flexure
Duodenum
Fig. 15.21 Attachment of liver to diaphragm
Left triangular lig.
Parietal
peritoneum
Bare area
Inferior
vena cava
Abdominal
aorta
Coronary lig.
Hepatic surface
of diaphragm
(no parietal
peritoneum)
Right
suprarenal gland
Right
triangular lig.
A
Diaphragmatic surface of
the liver, ­posterior view.
Right kidney
Stomach
Spleen
Hepatoduodenal
lig.
Pancreas
Duodenum
B
Hepatic surface of the
diaphragm, anterior view.
Clinical box 15.6
Hepatic cirrhosis
Hepatic cirrhosis is a condition leading to irreversible fibrosis of the liver
parenchyma. Alcohol abuse is the leading cause (70% of cases) followed by
hepatitis B. Portal hypertension with the development of collateral vessels
is a common result arising in approximately 30% of cases.
AT2W sequence. (Reproduced from
Krombach GA, Mahnken AH. Body
­Imaging: Thorax and Abdomen. New
York, NY: Thieme; 2018.)
Changes associated with advanced hepatic cirrhosis. All three sequences
show multiple regenerating nodules in the liver, creating a nodular surface
contour. Only the caudate lobe (B, arrow) is less affected by the changes and
still shows a relatively normal signal.
B
T1W sequence. (Reproduced from
Krombach GA, Mahnken AH. Body
­Imaging: Thorax and Abdomen. New
York, NY: Thieme; 2018.)
C
Fat-suppressed T1W sequence. (Reproduced
from Krombach GA, Mahnken AH. Body
­Imaging: Thorax and Abdomen. New York,
NY: Thieme; 2018.)
175
Abdomen
Liver: Lobes & Segments
Fig. 15.22 Surfaces of the liver
divides the liver into right and left anatomical lobes. The round
ligament of the liver is found in the free edge of the falciform ligament
and is the obliterated umbilical vein, which once extended from the
umbilicus to the liver.
The liver is divided into four lobes by its ligaments: right, left, caudate,
and quadrate. The falciform ligament, a double layer of parietal
peritoneum that reflects off the anterior abdominal wall and extends
to the liver, spreading out over its surface as visceral peritoneum,
Bare area
(diaphragmatic
surface of liver)
Coronary lig.
Right triangular lig.
Left triangular lig.
Fibrous
appendix
of liver
Left lobe,
diaphragmatic
surface
Right lobe,
diaphragmatic
surface
Falciform lig.
Round lig. of liver
(ligamentum
teres hepatis)
Inferior border
Gallbladder,
fundus
A
Anterior view.
Caudate
lobe
Fibrous
appendix of liver
Inferior
vena cava
Lig. of
vena cava
Bare
area
Caudate
process
Coronary lig.
Right lobe,
visceral surface
Left lobe,
visceral surface
Portal v.
Left hepatic duct
Right hepatic a.
Left hepatic a.
Right hepatic
duct
Proper hepatic a.
Round lig. of
liver (ligamentum
teres hepatis)
B
Inferior view.
176
Cystic a.
Quadrate
lobe
Bile duct
Cystic duct
Gallbladder
Left and intermediate
Groove for
hepatic vv.
inferior vena cava
Left triangular lig.
Right hepatic v.
15 Internal Organs
Coronary lig.
Fibrous
appendix of liver
Caudate lobe
Bare area
Ligamentum
venosum
Left lobe,
visceral surface
Caudate process
Portal v.
Right hepatic duct
Left hepatic a.
Right triangular lig.
Round lig. of liver
Branch of cystic a.
Cystic
duct
Proper
hepatic a.
Bile duct
Quadrate lobe
Right hepatic a.
Gallbladder
C
Posterior view.
Right lobe, visceral surface
IV
II
VIII
Fig. 15.23 Segmentation of the liver
The liver is divided into functional divisions, which are further
divided into segments (see Table 15.1). Each segment is served
by tertiary branches of the hepatic artery, the portal vein, and the
common hepatic duct, which together make up the portal triad.
VII
III
VI
Round lig.
of liver
V
Fibrous
appendix
A
Diaphragmatic
surface, anterior view.
I
VII
Inferior
vena cava
II
VI
III
V
B
Visceral surface, inferior
view.
Table 15.1
Branches of hepatic vv.
Branches of portal v.
Branches of proper hepatic a.
Branches of hepatic duct
Part
Left part
Round lig.
of liver
IV
Gallbladder
Hepatic segments
Division
Segment
Posterior part
I
Caudate lobe
II
Left posterolateral
III
Left anterolateral
IV
Left medial
V
Right anteromedial
Left lateral division
Left medial division
Right medial division
Right part
Right lateral division
VI
Right anterolateral
VII
Right posterolateral
VIII
Right posteromedial
177
Abdomen
Gallbladder & Bile Ducts
Fig. 15.24 Gallbladder:
Location
Fig. 15.25 Hepatic bile ducts: Location
Projection onto surface of the liver, anterior view.
Right duct of
caudate lobe
RUQ
Right
hepatic duct
Cystic duct
Gallbladder
Left hepatic
duct
Right
hepatic duct
Common
hepatic duct
Common
hepatic duct
Bile duct
Left duct of
caudate lobe
Liver,
left lobe
Cystic duct
Liver,
right lobe
Left hepatic
duct
A
Anterior view.
Bile duct
Bare area
Liver, caudate lobe
Inferior vena cava
Portal v.
Liver, left lobe
Right hepatic
duct
Left hepatic duct
Common
hepatic duct
Bile duct
Liver, quadrate lobe
Cystic duct
Gallbladder
B
Inferior view.
Fig. 15.26 Biliary sphincter system
Fig. 15.27 Extrahepatic bile ducts
Anterior view. Opened: Gallbladder and duodenum.
Sphincter
of bile duct
Duodenum
wall
Hepatopancreatic
ampulla
Gallbladder
Sphincter
of pancreatic
duct
Left
hepatic duct
Cystic duct
Common
hepatic duct
Neck
Sphincter of
hepatopancreatic
ampulla
A
Sphincters of the pancreatic
and bile ducts.
Right
hepatic duct
Infundibulum
Gallbladder
Duodenum,
superior part
Body
Bile duct
Bile duct
Fundus
Sphincter
of hepatopancreatic
ampulla
Longitudinal
slips of duodenal
muscle on bile
duct
Pancreatic
duct
B
Sphincter system in the duodenal wall.
178
Minor duodenal
papilla
Accessory
pancreatic duct
Pancreatic
duct
Major duodenal
papilla
Duodenum,
descending part
Duodenum,
horizontal part
Fig. 15.28 Biliary tract in situ
Inferior
vena cava
Hepatic
vv.
Esophagus
Abdominal
aorta
Spleen
Liver,
right lobe
Left
suprarenal
gland
Left hepatic
duct
Right hepatic
duct
15 Internal Organs
Anterior view. Removed: Stomach, small
intestine, transverse colon, and large
portions of the liver. The gallbladder
is intraperitoneal, covered by visceral
peritoneum where it is not attached to
the liver.
Celiac trunk
Common
hepatic duct
Splenic a.
Cystic duct
Common
hepatic a.
Proper
hepatic a.
Gallbladder
Left colic
flexure
Bile duct
Pancreas
Right colic
flexure
Left kidney
Hepatopancreatic
duct (opening
on major
duodenal
papilla)
Jejunum
Duodenum,
descending part
Pancreatic
duct
Duodenum,
ascending part
Superior mesenteric
a. and v.
Clinical box 15.7
Obstruction of the bile duct
Fig. 15.29 MR Cholangiopancreatography
(Reproduced from Moeller TB, Reif E. Pocket Atlas of Sectional
­Anatomy, Vol 2, 3rd ed. New York, NY: Thieme; 2007.)
Right
hepatic duct
Left hepatic
duct
Cystic duct
(spiral fold)
Common
hepatic duct
Body of
gallbladder
Pancreatic
duct
Neck of
gallbladder
Common bile
duct
Duodenum
As bile is stored and concentrated in the gallbladder, certain substances,
such as cholesterol, may crystallize, resulting in the formation of
gallstones. Migration of gallstones into the bile duct causes severe pain
(colic). Gallstones may also block the pancreatic duct in the papillary
regions, causing highly acute or even life-threatening pancreatitis.
Gallstones
Duodenal
papilla
Ultrasound appearance of two gallstones. Black arrows mark the echo-free
area behind the stones.
179
Abdomen
Pancreas & Spleen
Fig. 15.30 Pancreas and spleen: Location
RUQ
Stomach
LUQ
Omental bursa,
splenic recess
Pancreas
10th rib
Splenorenal
lig.
Spleen
Liver
Spleen
Pancreas
Gastrosplenic
lig.
Lesser
omentum
(hepatogastric
lig.)
Inferior
vena cava
B
Left lateral view.
A
Anterior view.
Duodenum,
superior part
Accessory
pancreatic duct
Pancreas,
neck Pancreatic
duct
Abdominal
aorta
Left
kidney
C
Transverse section through L1 vertebra, inferior view.
Fig. 15.31 Pancreas
Anterior view with dissection of the
pancreatic duct.
Pancreas,
body
Duodenum,
descending
part
Pancreas,
tail
Superior
mesenteric
a. and v.
Jejunum
Pancreatic duct
Duodenum,
Pancreas,
horizontal part
head
Pancreas,
uncinate process
Fig. 15.32 Spleen
Duodenum,
ascending part
Posterior
extremity
Posterior
extremity
Superior
border
Gastric
surface
Hilum
Superior
border
Splenic a.
Splenic v.
Renal
surface
Inferior
border
A
Costal surface.
180
Anterior
extremity
Diaphragmatic
surface
Inferior
border
Colic
surface
B
Visceral surface.
Anterior
extremity
Fig. 15.33 Pancreas and spleen in situ
Parietal
peritoneum
Inferior
vena cava
Hepatic
vv.
Left
Common
Celiac
hepatic a. gastric a. trunk
Diaphragm
Left suprarenal gland Superior
border
Gastric
surface
Spleen
Hepatic surface
of diaphragm
Right suprarenal
gland
15 Internal Organs
Anterior view. Removed: Liver, stomach, small
intestine, and large intestine. The pancreas
is retroperitoneal, whereas the spleen is
intraperitoneal.
Splenic
a. and v.
Hepatoduodenal
lig.
Pancreas, tail
Right kidney
Left colic
flexure
Pancreas,
body
Transverse
mesocolon,
root
Duodenum,
superior part
Pancreas,
head
Left kidney
Jejunum
Duodenum,
descending part
Descending
colon
Left colic
a. and v.
Duodenum,
horizontal part
Fig. 15.34 Pancreas and spleen:
Transverse section
Superior view. Section through
L1 vertebra.
Inferior
vena cava
Pancreas,
head
Mesentery
(root)
Pancreas,
uncinate
process
Spinal cord
(in vertebral
L1
canal)
vertebra
Duodenum, Superior mesenteric
ascending part
a. and v.
Abdominal
aorta
Splenic
a. and v.
Right kidney
Left kidney
and perirenal fat
Spleen
Parietal peritoneum
cut edge
Pancreas, tail
Right (hepatic)
colic flexure
Gastrosplenic
lig.
Omental
(epiploic)
foramen
Duodenum
Transverse
colon
Stomach
Portal
vein
Bile
duct
Proper
hepatic a.
Portal triad
Lesser omentum
(hepatoduodenal
and hepatogastric
ligs.)
Omental
bursa
(lesser sac)
Greater
omentum
Visceral
peritoneum
(cut edge)
181
Abdomen
Kidneys & Suprarenal Glands (I)
Fig. 15.35 Kidneys and suprarenal glands: Location
RUQ
LUQ
12th rib
Right
suprarenal
gland
Subcostal n.
Right kidney
Iliohypogastric n.
Right kidney
Left ureter
Ilioinguinal n.
Iliac crest
Urinary
bladder
B
Posterior view. Right side windowed.
A
Anterior view.
Right suprarenal
gland
Left suprarenal
gland
Fig. 15.36 Relations of the kidneys:
areas of organ contact.
Gastric
surface
Anterior view.
Splenic
surface
Hepatic surface
Pancreatic
surface
Right renal
hilum
Descending
colic surface
Right colic flexure
surface
Fig. 15.37 Right kidney in the renal bed
Duodenal
surface
Right lung
Right
ureter
Left
ureter
Left renal
hilum
Diaphragm
Perirenal fat capsule
Right suprarenal
gland
Right kidney
Renal hilum
Renal
fibrous capsule
Liver
Hepatorenal
recess
Abdominal Inferior
aorta
vena cava
Parietal
peritoneum
Renal fascia,
anterior layer
Renal fascia,
anterior layer
Parietal
peritoneum
Liver
Duodenum
Right kidney
Fat capsule
Renal fascia,
posterior layer
Iliac crest
Renal fascia,
posterior layer
Transverse
colon
L 1 vertebra
ASagittal section at approximately the level of the
renal hilum, viewed from the right side.
182
BTransverse section through the abdomen at approximately the L1/L2 level, viewed from above.
Fig. 15.38 Kidneys and
suprarenal glands in the
retroperitoneum
Inferior
Proper
Portal v. Hepatic vv. vena cava Esophagus hepatic a.
Splenic
fossa
Costodiaphragmatic recess
Hepatoduodenal
lig.
Left gastric a.
Right suprarenal
gland
Left suprarenal
gland
Hepatic ducts
15 Internal Organs
Anterior view. Both the kidneys
and ­suprarenal glands are retroperitoneal.
Diaphragm,
hepatic surface
Splenic a.
Right kidney
Pancreas
Duodenum,
superior part
Transverse
mesocolon,
root
Parietal
peritoneum
Left renal
a. and v.
Left kidney
Attachment
of descending
colon
Superior mesenteric
a. and v.
Attachment
of ascending
colon
Duodenum,
horizontal part
Mesentery,
root
Abdominal
aorta
Duodenum,
ascending part
Left colic
a. and v.
A
Removed: Intraperitoneal organs, along
with portions of the ascending and
descending colon.
Diaphragm
Inferior
vena cava
Esophagus
Right superior
suprarenal a.
Left superior
suprarenal a.
Abdominal
aorta
Left suprarenal
gland
Right suprarenal
gland
Celiac trunk
Left middle
and inferior
suprarenal aa.
Right suprarenal v.
Superior
mesenteric a.
Left suprarenal v.
Right inferior
suprarenal a.
Left renal a. and v.
Right renal
a. and v.
Left ovarian/testicular
a. and v.
Right kidney
Left ureter
Perirenal fat capsule
Right ureter
Iliohypogastric n.
Right ovarian/
testicular a. and v.
Ilioinguinal n.
Inferior mesenteric a.
B
Removed: Peritoneum, spleen and gastro­intestinal organs, along with fat capsule
(left side) Retracted: Esophagus
183
Abdomen
Kidneys & Suprarenal Glands (II)
Fig. 15.39 Kidney: Structure
Right kidney with suprarenal gland.
Pararenal
fat pad
Right suprarenal
gland
Right suprarenal gland
Superior suprarenal aa.
Superior pole
Middle suprarenal a.
Right suprarenal v.
Anterior
surface
Inferior suprarenal a.
Renal
cortex
Medial border
Fibrous
capsule
Right renal a. and v.
Lateral
border
Renal
hilum
Renal
hilum
Renal pelvis
Posterior
surface
Right ureter
Inferior pole
B
Posterior view.
Anterior view.
A
Renal cortex
Renal pyramid
Renal papilla
Minor calyx
Major calyx
Renal
a. and v.
Renal pelvis
Ureter
C
Posterior view with upper half partially removed.
184
Renal medulla
Medullary rays
Arcuate
a. and v.
Interlobar
a. and v.
Renal column
Fibrous
capsule
Renal papilla
Renal cortex
Major calyx
Segmental
aa. and v v.
Renal sinus
Renal
a. and v.
Renal pelvis
Ureter
DPosterior view, midsagittal section.
Medullary rays
Renal pyramid
Fibrous
capsule
Renal column
Minor calyx
Fig. 15.40 Right kidney and suprarenal gland
Anterior view. Removed: Perirenal fat capsule.
Retracted: Inferior vena cava.
Inferior vena cava
Inferior phrenic
a. and v.
Suprarenal v.
Superior
suprarenal aa.
Middle suprarenal a.
15 Internal Organs
Diaphragm
Celiac trunk
Right
suprarenal gland
Abdominal aorta
Inferior suprarenal a.
Superior mesenteric a.
Subcostal n.
(12th intercostal n.)
Left renal v.
Right kidney
Right renal a. and v.
Right ureter
Iliohypogastric n.
Right testicular/
ovarian a. and v.
Ilioinguinal n.
Fig. 15.41 Left kidney and suprarenal gland
Anterior view. Removed: Perirenal fat capsule.
Retracted: Pancreas.
Esophagus
Superior
suprarenal aa.
Left suprarenal
gland
Inferior
phrenic v.
Inferior vena cava
Diaphragm
Inferior phrenic a.
Anastomosis between
inferior phrenic v. and
suprarenal v.
Abdominal aorta
Portal v.
Left gastric a.
Middle suprarenal a.
Proper hepatic a.
Left suprarenal v.
Common hepatic a.
Subcostal n.
Bile duct
Pancreas, tail
Splenic a. and v.
Inferior suprarenal a.
Left renal a. and v.
Pancreas, neck
Superior mesenteric
a. and v.
Left kidney
Transversus abdominis,
internal and external
oblique
Duodenum
Left testicular/
ovarian a. and v.
Genitofemoral n.
Left
ureter
Ilioinguinal n.
Iliohypogastric n.
185
16
Neurovasculature
Abdomen
Arteries of the Abdominal Wall & Organs
Fig 16.1 Arteries of the
­abdominal wall
In addition to thoracic and
abdominal aortic branches, the
abdominal wall is supplied by
branches of the subclavian, external
iliac and femoral arteries. Numerous
potential anastomoses exist
between these vessels, which
allows the potential for blood to
bypass the abdominal aorta.
Superior
thoracic a.
Subclavian a.
Axillary a.
Lateral
thoracic a.
Subclavian
artery
Internal
thoracic a.
Aortic arch
Internal
thoracic a.
Posterior
intercostal aa.
Anterior
intercostal aa.
Thoraco­
dorsal a.
Superior
epigastric a.
Inferior
epigastric a.
Superficial
epigastric a.
Thoracic
aorta
Musculophrenic a.
Deep circumflex
iliac a.
External
iliac a.
Abdominal
aorta
Superficial
circumflex
iliac a.
Femoral a.
A Anterior view.
Superior
epigastric a.
Subcostal a.
1st–4th
lumbar aa.
Fig. 16.2 Abdominal aorta
and major branches
Inferior
epigastric a.
Anterior view. The abdominal aorta
extends from T12 to its bifurcation
at L4. It gives off visceral branches
to the kidneys, suprarenal glands,
gonads, and organs of the gas­
trointestinal system, and parietal
branches to the body wall.
External iliac a.
Femoral a.
Superior mesenteric a.
(L1)
Renal aa.
(L1/L2)
Inferior mesenteric a.
(L3)
Left common
iliac a.
Aortic bifurcation
(L4)
Right inferior
phrenic a.
Celiac
trunk
Left inferior
phrenic a.
Right superior
suprarenal a.
Left superior
suprarenal a.
Common hepatic a.
Left gastric a.
Table 16.1
Branches of the abdominal aorta
The abdominal aorta gives rise to three major unpaired trunks (bold)
and the unpaired median sacral artery, as well as six paired branches.
Branch from abdominal aorta
Branches
Inferior phrenic aa. (paired)
Superior suprarenal aa.
Splenic a.
Right gastric a.
Left middle
suprarenal a.
Proper hepatic a.
Gastroduodenal a.
Left inferior
suprarenal a.
Superior
mesenteric a.
Left gastric a.
Splenic a.
Celiac trunk
Left renal a.
Common
hepatic a.
Proper hepatic a.
Right gastric a.
Gastroduodenal a.
Middle suprarenal aa. (paired)
Right lumbar a.
Left testicular/
ovarian a.
Inferior
mesenteric a.
Superior mesenteric a.
Renal aa. (paired)
Inferior suprarenal aa.
Lumbar aa. (1st through 4th, paired)
Left common
iliac a.
Right common
illiac a.
Testicular/ovarian aa. (paired)
Inferior mesenteric a.
Common iliac aa. (paired)
Median sacral a.
186
B Lateral view.
Celiac trunk
(T12)
Median sacral a.
External iliac a.
Internal iliac a.
Common
hepatic a.
Fig. 16.3 Celiac trunk
Abdominal
aorta
Celiac trunk
Splenic a.
Splenic a. with
pancreatic brs.
Left
gastric a.
Common
hepatic a.
Proper
hepatic a.
Left
gastric a.
Gastroduodenal a.
A. of pan­
creatic tail
Gastro­
duodenal a.
Great pancreatic a.
Left gastro­ Posterior superior
pancreatico­
omental a.
duodenal a.
Pancreatic
Anterior superior
brs.
pancreatico­
Right gastro­
duodenal a.
omental a.
Right gastric a.
Anterior/posterior
superior pancreatico­
duodenal a.
Duodenal br.
Inferior pancreatico­
duodenal a.
Superior mesenteric a.
A
Celiac trunk distribution.
Inferior pancreatic a.
Dorsal pancreatic a.
Inferior pancreatico­
duodenal a.,
anterior br.
Superior
mesenteric a.
Arterial supply to the pancreas
B
Fig. 16.5 Inferior
mesenteric artery
Fig. 16.4 Superior mesenteric artery
Inferior pancreatico­
duodenal a.
16 Neurovasculature
Abdominal
aorta
Celiac
trunk
Inferior
mesenteric a.
Left
colic aa.
Left colic
flexure
Superior
mesenteric a.
Left colic
flexure
Middle colic a.
Right colic a.
Ileocolic a.
Jejunal and
ileal aa.
Appendicular a.
Fig. 16.6 Abdominal arterial anastomoses
Three major anastomoses provide overlap in the arterial supply to
abdominal areas to ensure adequate blood flow. Between the:
1–celiac trunk and the superior mesenteric artery via the pan­
creaticoduodenal arteries.
2–superior and inferior mesenteric arteries via the middle and left
colic arteries.
3–inferior mesenteric and the internal iliac arteries via the superior
and middle or inferior rectal arteries.
Superior
rectal a.
Celiac trunk
supplies:
Esophagus
Stomach
Duodenum
Liver
Spleen
Gallbladder
Pancreas
Superior mesenteric
a. supplies:
Pancreas
Duodenum
Jejunum
Ileum
Cecum
Ascending and
transverse colon
Inferior mesenteric
a. supplies:
Transverse,
descending and
sigmoid colon
Rectum
Anal canal
Sigmoid aa.
Pancreatico­
duodenal aa.
1
Middle colic a.
2
Left colic a.
3
Superior
rectal a.
Middle/inferior
rectal a.
Internal iliac a.
supplies: reproductive
organs
187
Abdomen
Abdominal Aorta & Renal Arteries
Fig. 16.7 Abdominal aorta
Anterior view of the female abdomen. Removed: All organs except the
left kidney and suprarenal gland. The abdominal aorta is the distal
continuation of the thoracic aorta (see p. 80). It enters the abdomen
at the T12 level through the aortic hiatus and courses anterior to the
vertebral bodies to the left of the midline before bifurcating into the
common iliac arteries at L4.
Esophagus
Inferior
vena cava
Left superior
suprarenal aa.
Left inferior
phrenic a.
Aortic hiatus
(median arcuate lig.)
Left middle
suprarenal a.
Celiac trunk
Left inferior
suprarenal a.
Superior
mesenteric a.
Left renal a.
Left 1st
lumbar a.
Abdominal aorta
Inferior
mesenteric a.
Left ovarian a.
(testicular a.
in males)
Right common
iliac a.
Left ureter
Median
sacral a.
Left iliolumbar a.
Right internal
iliac a.
Left superior
gluteal a.
Right external
iliac a.
Left lateral
sacral a.
Right
umbilical a.
Sacral
plexus
Right
obturator a.
Left deep
circumflex
iliac a.
Right inferior
vesical a.
Left inferior
epigastric a.
Right superior
vesical a.
Femoral a. and v.
Uterine a.
Obturator branch of right
inferior epigastric a.
188
Right middle
rectal a.
Right inferior
gluteal a.
Right internal
pudendal a.
Fig. 16.8 Renal arteries
Medullary (renal) pyramid
Arcuate a.
(at base of medullary
pyramids)
Minor calyx
Major calyx
Superior segmental a.
Anterior superior
segmental a.
Capsular brs.
16 Neurovasculature
Left kidney, anterior view. The renal
arteries arise at approximately L1/L2.
Each artery divides into an anterior
and a posterior branch. The anterior
Interlobar a.
branch further divides into four seg­
(between the
mental arteries (circled).
medullary pyramids)
Interlobular a.
Inferior suprarenal a.
Fibrous capsule
Left renal a.,
main trunk
Branch of posterior
segmental a.
Left renal a.,
anterior br.
Anterior inferior
segmental a.
Left renal a.,
posterior br.
Renal pelvis
Inferior segmental a.
Ureteral brs.
Left ureter
Clinical box 16.1
Clinical box 16.2
Variants of the renal artery
Anterior view of the right kidney. As the kidneys ascend from their site of
origin in the pelvis to the lumbar region, new renal arteries are formed as
older ones regress. Commonly some fail to regress, resulting in multiple
arteries to one or both kidneys.
Abdominal
aorta
Aberrant
right renal a.
Abdominal
aorta
Renal hypertension
The kidney is an important blood pressure sensor and regulator. Stenosis
(narrowing) of the renal artery reduces blood flow through the kidney
and stimulates increased production of renin, an enzyme that cleaves
angiotensinogen to form angiotensin I. Subsequent cleavage yields
angiotensin II, which induces vasoconstriction and an increase in blood
pressure. Renal hypertension should be excluded (or confirmed) when
diagnosing high blood pressure.
Accessory
renal a.
behind inferior
vena cava
Accessory
renal a. in
front of inferior
vena cava
Inferior vena cava
A
Accessory renal arteries pass
from the aorta to the renal
h
­ ilum. Note: one of the ­accessory
arteries is passing anterior to the
inferior vena cava.
Inferior vena cava
B
Aberrant renal arteries do
not enter the kidney at
the hilum.
Stenosis of the right renal artery (arrow),
visible via arteriography.
189
Abdomen
Celiac Trunk
Fig. 16.9 Celiac trunk: Stomach, liver, and gallbladder
Anterior view. Opened: Lesser omentum. Incised: Greater omentum.
The celiac trunk arises from the abdominal aorta at about the level
of T12. It supplies the structures of the foregut, the proximal part
of the alimentary canal and the spleen. The foregut consists of the
esophagus (distal 1.25 cm), stomach, duodenum (proximal half), liver,
gallbladder, and pancreas (superior portion).
Abdominal
aorta
Left hepatic a.
Right hepatic a.
Inferior
vena cava
Left gastric a.
Lesser
omentum
Liver
Stomach
Spleen
Gallbladder
Cystic a.
Proper
hepatic a.
Portal v.
Celiac trunk
Common
hepatic a.
Bile duct
Gastro­
duodenal a.
Right
gastric a.
Posterior
superior
pancreatico­
duodenal a.
Gastro­
duodenal a.
Duodenum
Anterior superior
pancreaticoduodenal a.
190
Right gastro­
omental a.
Splenic a.
Pancreas
Left gastro­
omental a.
Greater
omentum
16 Neurovasculature
Fig. 16.10 Celiac trunk: Pancreas, duodenum, and spleen
Anterior view. Removed: Stomach (body) and lesser omentum.
Inferior
vena cava
Common
hepatic a.
Left gastric a.
Celiac
trunk
Splenic a.
Posterior
gastric a.
Short
gastric aa.
Cystic a.
Proper
hepatic a.
Portal v.
Right gastric a.
Gastro­
duodenal a.
Splenic v.
Left gastro­
omental a.
A. of pancre­
atic tail
Supra­
duodenal a.
(variant)
Splenic a.,
pancreatic brs.
Posterior superior
pancreatico­
duodenal a.
Great
pancreatic a.
Anterior superior
pancreatico­
duodenal a.
Inferior
pancreatic a.
Duodenal br.
Right gastro­
omental a.
Inferior
pancreatico­
duodenal a.
Posterior br.
Anterior br.
Superior
mesenteric a.
and v.
Inferior pancreatico­
duodenal a.
Dorsal
pancreatic a.
Transverse
mesocolon, root
Anastomosis between
superior mesenteric a.
and inferior pancreatic a.
191
Abdomen
Superior & Inferior Mesenteric Arteries
Fig. 16.11 Superior mesenteric artery
Anterior view. Partially removed: Stomach, duodenum, and peritoneum.
Reflected: Liver and gallbladder. Note: The middle colic artery has been
truncated (see Fig. 16.12). The superior mesenteric artery arises from
the aorta opposite L1. It supplies the structures of the midgut: the
duodenum (distal half), jejunum and ileum, cecum and appendix,
ascending colon, right colic flexure, and the proximal two thirds of the
transverse colon.
Portal v.
Inferior vena cava
Proper hepatic a.
Right gastric a.
Gastroduodenal a.
Left
gastric a.
Common
hepatic a.
Splenic a.
Left renal v.
Right gastro­
omental a.
Anterior superior
pancreatico­
duodenal a.
Inferior pancreatico­
duodenal a., anterior
and posterior brs.
Left
renal a.
Superior
mesenteric a.
Middle
colic a. (cut)
Jejunal aa.
Right colic a.
Marginal a.
Ileocolic a.
Ileal aa.
Ileocolic a.,
colic br.
Ileocolic a.,
ileal br.
Posterior
cecal a.
Vasa recta
Anterior
cecal a.
Clinical box 16.3
Mesenteric ischemia
A decrease in blood flow to the intestine (ischemia) can result from occlusion
of the superior mesenteric artery (SMA) by a thrombus or embolus (acute) or
may be secondary to severe atherosclerosis (chronic). In the acute condition,
the embolus can obstruct the SMA at its origin or, if small enough, may
travel further to obstruct a more peripheral branch. Acute ischemia results
in necrosis of the affected part of the intestine. Chronic ischemia is less
192
threatening since obstruction of the vessels occurs gradually, allowing the
formation of collateral vessels that will supply the affected intestine. Because
of the extensive anastomoses between intestinal arteries, chronic vascular
ischemia is rare. Symptoms occur only if two of the three major vessels (celiac
trunk or superior or inferior mesenteric arteries) are compromised.
Fig. 16.12 Inferior mesenteric artery
Anterior view. Removed: Jejunum and ileum.
Reflected: Transverse colon.
Greater
omentum
Transverse
colon
Marginal a.
16 Neurovasculature
The inferior mesenteric artery arises from the
aorta opposite L3. It supplies structures of the
hindgut: the transverse colon (distal third), left
colic flexure, descending and sigmoid colons,
rectum, and anal canal (upper part).
Left colic (splenic)
flexure
Middle
colic a.
Superior
mesenteric a. (cut)
Duodenum
Right colic a.
Abdominal aorta
Descending colon
Inferior vena cava
Inferior
mesenteric a.
Ascending colon
Marginal a.
Left colic a.
Right common
iliac a.
Aortic bifurcation
Sigmoid aa.
Ileocolic a. (cut)
Ileocolic a.,
colic br.
Superior
rectal a.
Ileocolic a.,
ileal br.
Sigmoid colon
Posterior
cecal a.
Anterior
cecal a.
Clinical box 16.4
Anatomoses between arteries of the large intestine
Anastomoses between branches of the superior mesenteric and inferior
mesenteric arteries can compensate for abnormally low blood flow in
either of the arteries. Two of these anastomoses, although variable, are of
significant value:
Riolan’s arcade (arc of Riolan) – a connection between the middle colic artery
and the left colic artery that arises close to their origins from the superior and
inferior mesenteric arteries, respectively.
Middle colic a.
Superior
mesenteric a.
Left colic
flexure
Marginal a.
(of Drummond)
Arc of Riolan
Inferior
mesenteric a.
Left colic a.
Marginal artery (of Drummond) – a connection between all arteries of the
colon that runs along the periphery of the mesentery close to the intestinal
tube.
193
Abdomen
Veins of the Abdominal Wall & Organs
Fig 16.13 Veins of the
abdominal wall
Subclavian v.
The abdominal wall is drained
by veins that accompany the
arteries and are tributaries of
the azygos system and inferior
vena cava. Additionally, a large
thoracoepigastric vein connects
the femoral and axillary veins.
Axillary v.
Cephalic v.
Azygos v.
Superior vena cava
Areolar
venous plexus
Internal thoracic v.
Posterior
intercostal vv.
Anterior
intercostal vv.
Superior
epigastric v.
Musculophrenic v.
Thoracoepigastric v.
Periumbilical vv.
Superficial
epigastric v.
A Anterior view.
External pu­
dendal vv.
Great saphe­
nous v.
Superficial
circumflex iliac v.
Inferior vena cava
Subcostal v.
Femoral v.
Lumbar vv.
Fig. 16.14 Inferior vena cava
Anterior view. The inferior vena cava
arises at L5 with the convergence of
the common iliac veins. It ascends
along the right side of the vertebral
column, passes through the caval
opening in the diaphragm at T8 and
terminates in the thorax in the right
atrium of the heart.
Inferior epigastric v.
External iliac v.
Femoral v.
B Lateral view.
Inferior vena cava
L4 vertebra
Abdominal aorta
Common iliac vv.
Table 16.2
1R
1L
②
3R
Tributaries of the inferior vena cava
Inferior phrenic vv. (paired)
Hepatic vv. (3)
3L
Azygos v.
Suprarenal vv. (the right vein is a direct tributary)
1R
4R
4L
Renal vv. (paired)
5R
5L
Testicular/ovarian vv. (the right vein is a direct tributary)
6R
6L
Ascending lumbar vv. (paired), not direct tributaries
3R
7R
7L
Lumbar vv.
4R
8R
8L
Common iliac vv. (paired)
⑨
Median sacral v.
Inferior
vena cava
Hemiazygos v.
1L
②
3L
4L
5L
7R
6L
5R
7L
6R
8R
194
8L
⑨
Fig. 16.15 Portal vein
From hepatic vv.
within the liver to IVC
Left gastric v. (with
esophageal vv.)
Right
gastric v.
Short
gastric vv.
Splenic v.
Cystic v.
Pancreatic vv.
Portal v.
Splenic v.
Portal v.
Posterior superior
pancreatico­
duodenal v.
Inferior
mesen­
teric v.
L4
Superior
mesen­
teric v.
Left gastro­
omental v.
16 Neurovasculature
The portal vein (see p. 198) drains venous
blood from the abdominopelvic organs sup­
plied by the celiac trunk and superior and
inferior mesenteric arteries.
Right gastro­
omental v.
Inferior
pancreatico­
duodenal v.
Inferior
mesenteric v.
Superior
mesenteric v.
A
Location, anterior view.
Middle colic v.
Left colic v.
Right colic v.
Ileocolic v.
Sigmoid vv.
Appendicular v.
Subclavian v.
Right
Left
Esophageal
gastric v. gastric v.
vv.
Azygos/
hemi­
azygos v.
Superior
vena cava
A
Ileal Jejunal
vv.
vv.
Superior
rectal v.
B
Portal vein distribution.
Clinical box 16.5
Internal
thoracic v.
Portal v.
Inferior
vena cava
Paraumbilical vv.
Superior
epigastric v.
S
Common
iliac v.
Superior
mesenteric v.
Periumbilical vv.
S
Inferior
mesenteric v.
D
Colic vv.
F
Superior
rectal v.
Inferior
epigastric v.
Ascending
lumbar v.
D
Colic vv.
Middle/inferior
rectal v.
Cancer metastases
Tumors in the region drained by the superior
rectal vein may spread through the portal
venous system to the capillary bed of the
liver (hepatic metastasis). Tumors drained
by the middle or inferior rectal veins may
metastasize to the capillary bed of the lung
(pulmonary metastasis) via the inferior vena
cava and right heart.
C
Portocaval anastomotic collateral pathways
between the portal and systemic systems. When
the portal system is compromised, the portal
vein can divert blood away from the liver back
to its supplying veins, which return this nutrientrich blood to the heart via the venae cavae.
The red arrows indicate the flow reversal in the
(1) esophageal veins, (2) paraumbilical veins,
(3) the colic veins, and (4) the middle and infe­
rior rectal veins.
195
Abdomen
Inferior Vena Cava & Renal Veins
Fig. 16.16 Inferior vena cava
Anterior view of the female abdomen. Removed: All organs except the
left kidney and suprarenal gland. The inferior vena cava courses along
the right side of the vertebral bodies from its origin at L5 to the caval
opening in the diaphragm at T8. Unlike the branches of the aorta, vis­
ceral and parietal drainages to the inferior vena cava are asymmetrical
(note drainages of the suprarenal glands, gonads and azgygos veins).
It communicates with the azygos system through lumbar veins and
receives blood from the portal venous system via the hepatic veins.
Hepatic vv.
Left inferior
phrenic v.
Esophagus
Inferior vena cava
Celiac trunk
Right suprarenal v.
Left suprarenal v.
Superior
mesenteric a.
Left renal a. and v.
Left ovarian
a. and v.
Right renal v.
Ureter
Right ovarian
a. and v.
Abdominal aorta
Left ascending
lumbar v.
Left 3rd
lumbar v.
Inferior
mesenteric a.
Left common
iliac a. and v.
Right common
iliac v.
Deep circumflex
iliac a. and v.
Left lateral
sacral v.
Right internal
iliac v.
Left superior
gluteal v.
Right external
iliac v.
Right
obturator v.
Median sacral
a. and v.
Right middle
rectal v.
Right inferior
epigastric a.
and v.
Right internal
pudendal v.
Rectum
(and rectal
venous plexus)
Uterine venous
plexus
Right inferior
gluteal v.
Vesical venous
plexus
Right uterine v.
Right inferior
vesical v.
Femoral a. and v.
196
Vagina
Urethra
Fig. 16.17 Renal veins
Anterior view. See p. 189 for the renal arteries in isolation.
Removed: All organs except kidneys and suprarenal glands.
Right inferior
phrenic a. and v.
Left superior
suprarenal aa.
Inferior vena cava
16 Neurovasculature
Left inferior
phrenic v.
(anastomosis with
left suprarenal v.)
Left inferior
phrenic a.
Right superior
suprarenal a.
Celiac trunk
Right suprarenal v.
(typically opens
directly into inferior
vena cava)
Left middle
suprarenal a.
Left suprarenal v.
(typically opens
into left renal v.)
Right middle
suprarenal a.
Left inferior
suprarenal a.
Right inferior
suprarenal a.
Left renal
a. and v.
Right renal
a. and v.
Superior
mesenteric a.
Right testicular/
ovarian a. and v.
Left testicular/
ovarian a. and v.
Right ureter
Abdominal aorta
Ureteral branches
(from testicular/
ovarian a. or
common iliac a.)
Inferior
mesenteric a.
Clinical box 16.6
Tributaries of the left renal vein
On the right side, the suprarenal and testicular/ovarian veins drain
directly into the inferior vena cava. The corresponding veins on the
left side, however, drain into the left renal vein. (This is a remnant
from early development when there were both right and left sided
venae cave.) It is believed that this asymmetrical drainage pattern is
the cause of the varicose dilations of the veins in the spermatic cord
(varicoceles) that occur more commonly on the left side.
Right inferior
phrenic v.
Inferior
vena cava
Right
suprarenal v.
Right
renal v.
Right testicular/
ovarian v.
Left inferior
phrenic v.
Anastomosis
Left suprarenal v.
Left renal v.
Left testicular/
ovarian v.
197
Abdomen
Portal Vein
Fig. 16.18 Portal vein: Stomach and duodenum
Anterior view. Removed: Liver, lesser omentum, and peritoneum.
Opened: Greater omentum. The portal vein is typically formed by the
Common
hepatic a.
Inferior
vena cava
Hepatic
vv.
union of the superior mesenteric and the splenic veins posterior to
the neck of the pancreas.
Celiac
trunk
Esophageal
vv.
Left and right
hepatic aa.
Left gastric
a. and v.
Proper
hepatic a.
Short
gastric vv.
Portal v.
Spleen
Right kidney
and supra­
renal gland
Splenic
a. and v.
Gastro­
duodenal a.
Posterior
superior
pancreatico­
duodenal a.
Left gastro­
omental
a. and v.
Anterior
superior
pancreatico­
duodenal a.
Splenic a.
Pancreatico­
duodenal v.
Greater
omentum
Inferior pancreatico­
duodenal a.
198
Middle
colic v.
Superior
mesenteric a. and v.
Right gastro­
omental a. and v.
Right gastric
a. and v.
Fig. 16.19 Portal vein: Pancreas and spleen
Anterior view. Partially removed: Liver, stomach, pancreas, and
peritoneum.
Short
gastric vv.
Inferior vena
cava
Left gastric
a. and v.
Left and right
hepatic aa.
16 Neurovasculature
Hepatic vv.
Celiac trunk
Proper
hepatic a.
Splenic
a. and v.
Portal v.
Splenic v.
Right
gastric a.
Inferior
pancreatic a.
Gastro­
duodenal a.
Left gastro­
omental a. and v.
Right
gastric v.
Left supra­
renal v.
Posterior and
anterior
superior
pancreatico­
duodenal aa.
Left renal
a. and v.
Left ureter
Pancreatico­
duodenal v.
Inferior pancreatico­
duodenal a., anterior
and posterior brs.
Middle
colic v.
Superior
mesenteric
a. and v.
Right
gastro­
omental
a. and v.
Left ovarian/
testicular
Inferior
a. and v.
Left
ascending mesenteric v.
lumbar v.
Clinical box 16.7
Esophageal varices
Upper esophageal veins drain into the azygos system, but
the lower esophagus drains into the portal system via the
left gastric veins. As a result of this portocaval anastomosis,
venous varices (dilations, arrows) of the esophageal wall may
develop in patients with portal hypertension. Severe acute
hemorrhage is the greatest risk associated with this condition.
199
Abdomen
Superior & Inferior Mesenteric Veins
Fig. 16.20 Superior mesenteric vein
Anterior view. Partially removed: Stomach, duodenum, and peritoneum.
Removed: Pancreas, greater omentum, and transverse colon. Reflected:
Liver and gallbladder. Displaced: Small intestine. The superior mesen­
teric vein receives tributaries from the entire small intestine as well as
the cecum, appendix, ascending colon, and two thirds of the transverse
colon. It normally lies to the right of the superior mesenteric artery
then joins with the splenic vein posterior to the neck of the pancreas
to form the portal vein.
Left gastric
a. and v.
Proper
hepatic a.
Inferior vena cava
Portal v.
Splenic a. and v.
Right gastric
a. and v.
Left renal a.
Inferior mesenteric v.
Gastro­
duodenal a.
Right gastro­
omental a. and v.
Middle colic
a. and v.
Pancreatico­
duodenal
a. and vv.
Superior mesenteric
a. and v.
Right colic
a. and v.
Inferior
vena cava
Jejunal aa.
and vv.
Ileocolic
a. and v.
Ileocolic a.,
colic br.
Ileal aa.
and vv.
Cecal vv.
Posterior cecal a.,
appendicular v.
200
Anterior
cecal a.
Ileocolic a.,
ileal br.
Fig. 16.21 Inferior mesenteric vein
Portal v.
from the artery, and generally joins with the splenic vein posterior to
the stomach and pancreas. Note that the ascending and descending
colons may also be drained by lumbar veins in the retroperitoneum,
which empty into the inferior vena cava, constituting a portocaval
collateral pathway.
Inferior vena cava
Left gastric
a. and v.
16 Neurovasculature
Anterior view. Partially removed: Stomach, duodenum, and peritoneum.
Removed: Pancreas, greater omentum, transverse colon, and small
intestine. Reflected: Liver and gallbladder. The inferior mesenteric vein
drains a smaller territory than the superior mesenteric vein. It receives
tributaries from the distal transverse colon, descending and sigmoid
colons and upper rectum. It ascends in the retroperitoneum, separate
Proper hepatic a.
Splenic a. and v.
Right gastric
a. and v.
Left renal a.
Gastro­
duodenal a.
Inferior
mesenteric v.
Right gastro­
omental a. and v.
Middle colic
a. and v.
Superior
mesenteric
a. and v.
Right colic
a. and v.
Left colic
a. and v.
Ileocolic
a. and v.
Jejunal/ileal
aa. and vv. (cut)
Inferior mesenteric
a. and v.
Left common
iliac a. and v.
Sigmoid
aa. and vv.
Cecal vv.
Posterior cecal a.
Anterior cecal a.
Superior rectal a. and v.
201
Abdomen
Lymphatics of the Abdominal Wall & Organs
Fig. 16.22 Lymphatic drainage of the anterior trunk wall
Lymph from the skin of the trunk wall is collected mainly by the axil­
lary and superficial inguinal lymph nodes (arrows indicate direction of
lymph flow). A curved line that lies between the umbilicus and costal
arch defines the “watershed” zone between the two drainages. Lymph
from the right upper quadrant (green) is drained by the right lymphatic
duct. Lymph from the remainder of the body (blue) is drained by the
thoracic duct.
Cervical l.n.
Axillary l.n.
Parasternal l.n.
“Watershed”
Superficial
inguinal l.n.
Fig. 16.23 Lymphatic drainage of the internal organs
See Table 16.3 for numbering. Lymph drainage from the abdomen,
pelvis, and lower limb ultimately passes through the lumbar lymph
nodes (clinically, the aortic nodes), which consist of the right lateral
aortic (caval) and left lateral aortic nodes, the preaortic nodes, and
the retroaortic nodes.
Efferent lymph vessels from the lateral aortic, retroaortic, and inferior
mesenteric nodes form the lumbar trunks. Those from the remaining
preaortic nodes form the intestinal trunks. The lumbar and intestinal
trunks terminate in the cisterna chyli.
① Inferior phrenic l.n.
② Celiac l.n.
Preaortic l.n.
Lumbar l.n.
③ Superior mesenteric l.n.
④ Inferior mesenteric l.n.
⑤ Left lateral aortic l.n.
⑥ Right lateral aortic (caval) l.n.
Cisterna chyli
Thoracic duct
Parietal lymph nodes
of the abdomen
Table 16.3
⑦ Retroaortic l.n.
Intestinal trunk
⑧ Common iliac l.n.
Right lumbar
trunk
③
⑥
Left lumbar
trunk
②
②
⑤
④
⑧
Right common
iliac l.n.
①
⑧
③
Cisterna
chyli
Lumbar
l.n.
⑦
⑤
⑥
④
Left common
iliac l.n.
⑧
202
Lateral aortic l.n.
Preaortic l.n.
16 Neurovasculature
Splenic l.n.
Left lumbar l.n.
Hepatic l.n.
Superior mesenteric l.n.
Cystic l.n.
Foraminal l.n.
Juxta­intestinal l.n.
Prececal l.n.
Retrocecal l.n.
Celiac l.n.
Ileocolic l.n.
Appendicular l.n.
Right/left
gastric l.n.
Mesocolic l.n.
Pyloric l.n.
Right colic l.n.
Supra­, sub­, and
retropyloric l.n.
Middle colic l.n.
Right left gastroomental l.n.
Superior/inferior
pancreatic l.n.
Superior/inferior
pancreaticoduodenal
l.n.
Mesocolic l.n.
Left colic l.n.
Inferior mesenteric l.n.
Sigmoid l.n.
Superior rectal l.n.
Fig. 16.24 Principal lymphatic pathways draining the
digestive organs and spleen
Lymph from the spleen and most digestive organs drains directly from
regional lymph nodes or through intervening collecting nodes to the
intestinal trunks, except for the descending and sigmoid colon and the
upper part of the rectum, which are drained by the left lumbar trunk.
The three large collecting nodes are:
• Celiac lymph nodes collect lymph from the stomach, duodenum,
pancreas, spleen, and liver. Topographically and at dissection they
are often indistinguishable from the regional lymph nodes of the
nearby upper abdominal organs.
• Superior mesenteric lymph nodes collect lymph from the jejunum,
ileum, ascending and transverse colon.
• Inferior mesenteric lymph nodes collect lymph from the descending
and sigmoid colon and rectum.
These nodes drain principally through the intestinal trunks to the
cisterna chyli, but there is an accessory drainage route by way of the
left lumbar lymph nodes. Lymph from the pelvis also drains up into the
inferior mesenteric and lateral aortic lymph nodes. A complete drainage
pathway for lymph from the pelvis can be found on p. 276.
203
Abdomen
Lymph Nodes of the Posterior Abdominal Wall
Lymph nodes in the abdomen and pelvis may be classified as either pa­
rietal or visceral. The majority of the parietal lymph nodes are located
on the posterior abdominal wall.
Fig. 16.25 Parietal lymph nodes in the abdomen and pelvis
Anterior view. Removed: All visceral structures except vessels.
Inferior vena cava
Esophagus
Diaphragm
Celiac l.n.
Inferior
phrenic l.n.
Abdominal aorta
Superior
mesenteric l.n.
Cisterna chyli
Right lumbar
trunk
Retrocaval l.n.
Intermediate
lumbar l.n.
Right lateral
caval l.n.
Common
iliac a.
Sacral l.n.
Intestinal trunk
Left lumbar trunk
Retroaortic l.n.
Left lateral aortic l.n.
Inferior mesenteric l.n.
Common
iliac l.n.
Internal
iliac l.n.
External
iliac l.n.
Inguinal
lig.
Intermediate
lacunar l.n.
Deep
inguinal l.n.
204
Superficial inguinal
l.n. (horizontal
and vertical groups)
16 Neurovasculature
Fig. 16.26 Lymph nodes of the kidneys, ureters, and
­suprarenal glands
Anterior view.
Inferior phrenic l.n.
Retrocaval l.n.
Left lateral aortic l.n.
Right lateral caval l.n.
Preaortic l.n.
Intermediate lumbar l.n.
Common iliac l.n.
Promontory l.n.
Fig. 16.27 Lymphatic drainage of the kidneys and gonads
(with pelvic organs)
Thoracic duct
Right lumbar trunk
Cisterna chyli
Left lumbar trunk
Right lumbar l.n.
Left lumbar l.n.
Lateral caval l.n.
Lateral aortic l.n.
Intermediate lumbar l.n.
Precaval l.n.
Preaortic l.n.
Retrocaval l.n.
Lacunar l.n. (lateral,
medial, and intermediate)
Deep inguinal l.n.
Retroaortic l.n.
External iliac l.n.
Common iliac l.n.
Internal iliac l.n.
Obturator l.n.
Subaortic l.n.
Sacral l.n.
Lateral, medial, and
intermediate external
iliac l.n.
Promontory l.n.
Superior and inferior
gluteal l.n.
Interiliac l.n.
Lateral, medial, and
intermediate common
iliac l.n.
Superficial inguinal l.n.
Lower limb, uterus,
and vagina
205
Abdomen
Lymph Nodes of the Supracolic Organs
Fig. 16.28 Lymph nodes
of the stomach and liver
Anterior view. Removed: Lesser omentum.
Opened: Greater omentum. Arrows show
direction of lymphatic drainage.
Inferior vena cava
Celiac l.n.
Cardiac
lymphatic ring
Left gastric
l.n.
Splenic l.n.
Hepatic l.n.
Portal v.
Left gastro­
omental l.n.
Pancreatic l.n.
Suprapyloric l.n.
Subpyloric l.n.
Right gastro­
omental l.n.
Fig. 16.29 Lymphatic drainage of the liver
and biliary tract
Anterior view. In the region of the liver, the major lymph-producing
organ, the important pathways are:
• Liver and intrahepatic bile ducts: Most lymph drains inferiorly through
the hepatic nodes to the celiac nodes and then to the
intestinal trunk and cisterna chyli, but it may take a more direct
route bypassing the celiac nodes. A small amount drains cranially
through the inferior phrenic nodes to the lumbar trunk. It also can
drain through the diaphragm to the superior phrenic nodes and on
to the bronchomediastinal trunk.
• Gallbladder: Lymph drains initially to the cystic node, then follows
one of the pathways described above.
• Common bile duct: Lymph drains through the pyloric nodes
(supra-, sub-, and retropyloric) and the foraminal node to the
celiac nodes, then to the intestinal trunk.
206
Diaphragm
Inferior
phrenic l.n.
Superior
phrenic l.n.
Liver
Hepatic l.n.
Inferior
vena cava
Stomach
Cystic l.n.
Celiac trunk
with celiac l.n.
Gallbladder
Pancreas
Duodenum
Pyloric l.n.
Bile duct
Fig. 16.30 Lymph nodes of the spleen, pancreas,
and duodenum
Anterior view. Removed: Stomach and colon.
16 Neurovasculature
Left gastric l.n.
Cystic l.n.
Splenic l.n.
Hepatic l.n.
Celiac l.n.
Suprapyloric l.n.
Pancreatic l.n.
(superior)
Retropyloric l.n.
Subpyloric l.n.
Pancreatic l.n.
(inferior)
Superior
mesenteric l.n.
Pancreaticoduodenal
l.n.
Fig. 16.31 Lymphatic drainage of the stomach, liver,
spleen, pancreas, and duodenum
Thoracic duct
Cisterna chyli
Hepatic l.n.
Intestinal trunks
Splenic l.n.
Cystic l.n.
Foraminal l.n.
Celiac l.n.
Superior mesenteric l.n.
Pancreatic l.n.
(superior and inferior)
Pancreaticoduodenal l.n.
(superior and inferior)
Gastric l.n. (right and left)
Pyloric l.n.
Supra­, sub­, and
retropyloric l.n.
Gastro­omental l.n.
(right and left)
207
Abdomen
Lymph Nodes of the Infracolic Organs
Fig. 16.32 Lymph nodes of the jejunum and ileum
Anterior view. Removed: Stomach, liver, pancreas, and colon.
Abdominal aorta
Celiac l.n.
Thoracic duct with
cisterna chyli
Superior
mesenteric l.n.
Transverse colon
Duodenum
Ascending colon
Jejunum
Intermediate
mesenteric l.n.
Ileocolic l.n.
Juxta­intestinal l.n.
Ileum
Fig. 16.33 Lymphatic drainage of the intestines
Thoracic duct
Left lumbar l.n.
Left lumbar trunk
Cisterna chyli
Intestinal trunks
Lateral aortic l.n.
Preaortic l.n.
Superior mesenteric l.n.
Juxta­intestinal l.n.
Inferior mesenteric l.n.
Mesocolic l.n.
Sigmoid l.n.
Left colic l.n.
Superior rectal l.n.
Middle colic l.n.
Right colic l.n.
208
Prececal l.n.
Retrocecal l.n.
Ileocolic l.n.
Appendicular l.n.
16 Neurovasculature
Fig. 16.34 Lymph nodes of the large intestine
Anterior view. Reflected: Transverse colon and greater omentum.
Epicolic l.n.
Middle colic l.n.
Right colic l.n.
Superior
mesenteric l.n.
Left colic l.n.
Paracolic l.n.
Inferior
mesenteric l.n.
Ileocolic l.n.
Intermediate
colic l.n.
Sigmoid l.n.
Prececal l.n.
Superior
rectal l.n.
Clinical box 16.8
Lymphatic drainage of the large intestine
Regional lymphatic pathways in the large intestine have important clinical
affects.
• Upper rectum: Lymph drains initially to the superior rectal nodes then fol­
lows the pathway described above for the sigmoid colon.
• Ascending colon, cecum, and transverse colon: Lymph drains initially to
the right and middle colic nodes, then to the superior mesenteric nodes, and
finally to the intestinal trunk.
• Descending colon: Lymph drains initially to the regional left colic nodes,
then to the inferior mesenteric nodes, then via the left lumbar nodes into the
left lumbar trunk.
• Sigmoid colon: Lymph drains initially to sigmoid nodes then follows the
pathway described above for the descending colon.
Thus, a malignant tumor undergoing lymphogenous spread must negotiate
several lymph node groups (all of which should be removed in tumor resections) before the malignant cells can reach the intestinal trunk and thoracic
duct and finally enter the bloodstream. This long route of lymphogenous
spread improves the prospects for a cure.
209
Abdomen
Nerves of the Abdominal Wall
Fig. 16.35 Somatic nerves of
the abdomen and pelvis
Anterior view. The abdominal wall is
innervated by somatic nerves that
include the lower intercostal nerves
and branches of the lumbar plexus.
Intercostal nn.
Intercostal nn.
Subcostal n.
Lumbar plexus
Iliohypogastric n.
Ilioinguinal n.
Genitofemoral n.
Obturator n.
Sacral plexus
Femoral n.
Sciatic n.
Fig. 16.36 Cutaneous innervation of the anterior trunk
Anterior view.
Fig. 16.37 Dermatomes of the anterior trunk
Anterior view.
C3
Supraclavicular nn.
C4
T2
T3
C5
Intercostal nn.,
lateral cutaneous brs.
Iliohypogastric n.,
lateral cutaneous br.
Lateral femoral
cutaneous n.
Femoral n., anterior
cutaneous brs.
210
Intercostal nn.,
anterior cutaneous brs.
Iliohypogastric n.,
anterior cutaneous br.
Genitofemoral n.,
femoral br.
Ilioinguinal n.
T4
C6
T1
T 10
L2
T 12
L3
L1
C8
S2
C7
L4
Fig. 16.38 Nerves of the lumbar plexus
Anterior view.
16 Neurovasculature
Inferior vena cava
Lateral
arcuate lig.
Diaphragm,
lumbar part
Median arcuate
lig.
Subcostal n.
Medial arcuate
lig.
Quadratus
lumborum
Sympathetic
trunk
Transversus
abdominis
Abdominal
aorta
Iliohypogastric n.
Ilioinguinal n.
Psoas major
and minor
Genital br.
Iliacus
Genitofe­
moral n.
Femoral br.
Iliohypogastric
n., lateral
cutaneous br.
Femoral n.
Lateral femoral
cutaneous n.
Iliohypogastric n.,
anterior cutaneous br.
Ilioinguinal n.
Genitofemoral
n., femoral br.
Genitofemoral n.,
genital br.
Femoral n.,
anterior
cutaneous br.
Abdominal
aorta
Subcostal n.
Genitofemoral
n.
Iliohypogastric
n.
A
Lumbar plexus in situ. Removed:
All visceral structures except vessels.
Lumbar
plexus
Ilioinguinal n.
Lateral femoral
cutaneous n.
Obturator n.
Femoral n.
Sympathetic
trunk
Inferior
vena cava
Common
iliac a.
Internal
iliac a.
External iliac a.
Genitofe­
moral n.
Femoral br.
Genital br.
Lumbar plexus, dissection.
B
Windowed: Psoas major and minor muscles.
211
Autonomic Innervation: Overview
Sympathetic
Parasympathetic
Sympathetic
Abdomen
Head and neck
Fig. 16.39 Sympathetic and parasympathetic
nervous systems in the abdomen and pelvis
Superior
cervical
ganglion
Superior
cervical
ganglion
Sympathetic trunk
C8
T1
Superior
cervical
ganglion
C8
Head and neck
Sympathetic trunk
Vagus n.
T1
Sympathetic
(prevertebral)
ganglia
T5
Celiac ganglionSympathetic trunk
T1
Thoracic
splanchnic nn.
Dorsal
Vagus
n.
vagal
nucleus
Sympathetic
(prevertebral)
ganglia
Celiac ganglion
Dorsal
vagal
nucleus
Vagus n.
Sympathetic
Thoracic
(prevertebral)
splanchnic
nn.
ganglia
T5
L1
Lumbar
splanchnic nn.
Dorsal
vagal
nucleus
Parasympathetic
Sympathetic
C8
T5
Head and neck
Parasympathetic
Celiac ganglion
L1
Lumbar
splanchnic nn.
Thoracic
splanchnic nn.
Sacral
splanchnic nn.
S2
Sacral
splanchnic nn.
L1
Lumbar
**Inferior
Superior and inferior
splanchnic nn.
hypogastric
mesenteric ganglia
{with intermesenteric plexus) plexus
S2
S4
**Inferior
Superior and inferior
Pelvic splanchnic nn.
hypogastric
mesenteric ganglia
{with intermesenteric plexus) Sympathetic
plexus
preganglionic fibers
S4
Pelvic splanchnic nn.
Sympathetic preganglionic fibers
S2
Sympathetic
postganglionic fibers
Sympathetic postganglionic fibers
Sacral
**Minimal
sympathetic preganglionic fibers traveling
sympathetic preganglionic
fibers traveling
Parasympathetic
preganglionic fibers
splanchnic
nn. the sacral splanchnic nerves will synapse**Minimal
through
in
Parasympathetic
preganglionic fibers
through the sacral splanchnic nerves
will synapsepostganglionic
in
S4
the ganglia located in the inferior hypogastric plexus
Parasympathetic
fibers
the ganglia located in the inferior hypogastric plexus
Parasympathetic postganglionic fibers
**Inferior
Superior and inferior
hypogastric
mesenteric ganglia
Pelvic splanchnic nn.
{with intermesenteric plexus) plexus
Sympathetic preganglionic fibers
Sympathetic postganglionic fibers
**Minimal sympathetic preganglionic fibers traveling
Parasympathetic preganglionic fibers
through the sacral splanchnic nerves will synapse in
the ganglia located in the inferior hypogastric plexus
Parasympathetic postganglionic fibers
Table 16.4
Effects of the autonomic nervous system in the abdomen and pelvis
Organ (organ system)
Gastrointestinal
tract
Parasympathetic effect
Longitudinal and circular muscle fibers
↓ motility
↑ motility
Sphincter muscles
Contraction
Relaxation
Glands
↓ secretions
↑ secretions
Splenic capsule
Contraction
Liver
↑ glycogenolysis/gluconeogenesis
Pancreas
Urinary bladder
212
Sympathetic effect
No effect
Endocrine pancreas
↓ insulin secretion
Exocrine pancreas
↓ secretion
↑ secretion
Detrusor vesicae
Relaxation
Contraction
Functional bladder sphincter
Contraction
Inhibits contraction
Seminal glands and ductus deferens
Contraction (ejaculation)
Uterus
Contraction or relaxation, depending on
hormonal status
Arteries
Vasoconstriction
Vasodilation of the arteries of the penis and
clitoris (erection)
Suprarenal glands (medulla)
Release of adrenalin
No effect
Urinary tract
Vasoconstriction (↓ urine formation)
Vasodilation
Kidney
No effect
Ganglia
Subplexus
Distribution
Celiac plexus
Sympathetic trunk
with lumbar ganglia
Celiac ganglia
Hepatic plexus
• Liver, gallbladder
Gastric plexus
• Stomach
Splenic plexus
• Spleen
Pancreatic plexus
• Pancreas
16 Neurovasculature
Autonomic plexuses in the abdomen
and pelvis
Table 16.5
Superior mesenteric plexus
Superior
mesenteric
ganglion
—
• Pancreas (head)
• Duodenum
• Jejunum
• Ileum
• Cecum
• Colon (to left
colic flexure)
• Ovary
Suprarenal and renal plexus
Aorticorenal
ganglion
Intermesenteric plexus
Ureteral plexus
• Suprarenal gland
• Kidney
• Proximal ureter
Ovarian/testicular plexus
—
Lumbar splanchnics
—
• Ovary/testis
Inferior mesenteric plexus
Iliac plexus
Inferior
mesenteric
ganglion
Left colic plexus
• Left colic flexure
Superior rectal
plexus
• Descending and sigmoid colon
• Upper rectum
Superior hypogastric plexus
—
Hypogastric nn.
• Pelvic viscera
Inferior hypogastric plexus
Sacral splanchnic
Middle and inferior
rectal plexus
• Middle and lower rectum
Prostatic plexus
• Prostate
• Seminal gland
•B
ulbourethral
gland
Deferential plexus
• Ductus deferens
• Epididymis
Uterovaginal plexus
• Uterus
• Uterine tube
Vesical plexus
• Urinary bladder
Ureteral plexus
• Ureter (ascending from pelvis)
Sacral ganglia
Hypogastric nn.
Pelvic ganglia
Ganglion
impar
• Ejaculatory
duct
• Penis
• Urethra
• Vagina
• Ovary
Note: The two sacral sympathetic trunks converge and terminate in front of
the coccyx in a small ganglion, the ganglion impar.
213
Abdomen
Autonomic Innervation & Referred Pain
Pain afferents from the viscera (visceral pain) and dermatomes (somatic
pain) terminate at the same processing neurons in the posterior horn
of the spinal cord. The convergence of these visceral and somatic affer­
ent fibers confuses the relationship between the pain’s origin and its
Fig. 16.40 Autonomic
innervation of the
liver, gallbladder,
and stomach
perception. This phenomenon is called referred pain. The pain impulses
from a particular internal organ are consistently projected to the same
well-defined skin area. Thus,Posterior
the area of skin that the pain is projected
vagal trunk
to provides crucial information
regarding what organ is affected.
Sympathetic
trunk
Posterior
vagal trunk
Anterior
vagal trunk
Right greater
splanchnic n.
Anterior
vagal trunk
Right greater
splanchnic
n.
Gallbladder
Left greater
splanchnic n
Hepatic br.
of posterior
vagal trunk
Liver and
gallbladder
Celiac ganglia Stomach
Celiac br.
of anterior
vagal trunk
Left greater
splanchnic n.
Hepatic br.
of posterior
vagal trunk
Sympathetic
trunk
Celiac ganglia
Celiac br.
of anterior
vagal trunk
BZones of referred pain from the liver,
gallbladder, and stomach.
Posterior
gastric plexu
Pyloric br.
of anterior
vagal trunk
Posterior
gastric plexus
ASchematic of celiac
plexus distribution to
the liver, gallbladder,
and stomach.
Pyloric br.
of anterior
vagal trunk
Hepatic
plexus
Hepatic br. of
anterior vagal trunk
Hepatic
plexus
Pyloric br.
of posterior
vagal trunk
Hepatic br. of
anterior vagal trunk
Sympathetic preganglionic fibers
Sympathetic postganglionic fibers
Pyloric br.
of posterior
vagal trunk
Parasympathetic preganglionic fibers
Parasympathetic postganglionic fibers
Symp
trunk
Posterior
vagal trunk
Sympathetic preganglionic fibers
Sympathetic postganglionic fibers
Fig. 16.41 Autonomic
innervation of the
pancreas, duodenum,
and spleen
Parasympathetic preganglionic fibers
Parasympathetic postganglionic fibers
Posterior
vagal trunk
Sympathetic
trunk
Anterior
vagal trunk
Celiac ganglia
Anter
vagal
Left greater
splanchnic n.
Celiac ganglia
Splenic
plexus
Brs. of
celiac plexus
to duodenum
Splenic
plexus
Brs. of
celiac plexus
to duodenum
BZones of referred pain from the pan­
creas. There are no zones associated
with the duodenum and spleen.
Brs. of superior mesenteric
plexus to pancreas and duodenum
Superior
mesenteric
ganglion
Brs. of superior mesenteric
plexus to pancreas and duodenum
Sympathetic preganglionic fibers
214
Sympathetic postganglionic fibers
Parasympathetic preganglionic fibers
Parasympathetic postganglionic fibers
Pancr
plexu
Superior
mesente
ganglion
Pancreatic
plexus
ASchematic of celiac
plexus distribution
to the pancreas,
­duodenum, and
spleen.
Left g
splan
Sympathetic preganglionic fibers
Sympathetic postganglionic fibers
Parasympathetic preganglionic fibers
Parasympathetic postganglionic fibers
Fig. 16.42 Autonomic innervation
of the midgut and hindgut
Sympathetic
Sympathetic
trunk
trunk
Posterior
Posterior
vagal trunk
vagal trunk
Celiac
Celiac
ganglia
ganglia
Superior
Superior
mesenteric
mesenteric
Small
ganglion
ganglion
intestine
Greater splanchnic n.
Greater splanchnic n.
(T5-T9)
(T5-T9)
Posterior
vagal trunk
Celiac
ganglia
Lesser splanchnic n.
(T10-T11)
Superior
mesenteric
ganglion
Superior
mesenteric
plexus
Least splanchnic n.
(T12)
Sacral splanchnic nn.
Sacral splanchnic nn.
(S1-S3)
(S1-S3)
Intermesenteric
plexus
Lumbar splanchnic n.
(L1-L2)
Inferior
mesenteric ganglion
Lumbar splanchnic n.
(L3-L5)
Inferior mesenteric
plexus
Superior rectal
plexus
Inferior
rectal plexus
Inferior hypogas
Inferior hypogas
plexus and
plexus and
pelvic ganglia*
pelvic ganglia*
Sympathetic preganglionic fibers
Sympathetic preganglionic fibers
Sympathetic postganglionic fibers
Sympathetic postganglionic fibers
Parasympathetic preganglionic fibers
Parasympathetic preganglionic fibers
Parasympathetic postganglionic fibers
Parasympathetic postganglionic fibers
Sacral splanchnic nn.
(S1-S3)
Inferior hypogastric
plexus and
pelvic ganglia**
Inferior
Inferior
p
p
intestine.
Pelvic splanchnic nn.
Pelvic splanchnic nn.
(S2-S4)
(S2-S4)
Superior
hypogastric plexus
Pelvic splanchnic nn.
(S2-S4)
Interm
Interm
p
p
Large
intestine
Lumbar splanchnic n.
Inferior
Lumbar splanchnic n.
Inferior
(L1-L2)
mesenteric
ganglion
(L1-L2)
mesenteric ganglion
Lumbar splanchnic n.
Lumbar splanchnic n.
(L3-L5)
BZones of referred pain Superior
Superior
(L3-L5)
hypogastric plexus
plexus
from the small andhypogastric
large
Sympathetic
trunk
Greater splanchnic n.
(T5-T9)
16 Neurovasculature
Lesser splanchnic n.
Lesser splanchnic n.
(T10-T11)
(T10-T11)
Least splanchnic n.
Least splanchnic n.
(T12)
(T12)
Su
Su
me
me
p
p
Middle rectal
plexus
**Minimal sympathetic preganglionic fibers traveling
**Minimal sympathetic preganglionic fibers traveling
through the sacral splanchnic nerves will synapse in
through the sacral splanchnic nerves will synapse in
the ganglia located in the inferior hypogastric plexus.
the ganglia located in the inferior hypogastric plexus.
ASchematic
of superior mesenteric,
Sympathetic preganglionic fibers
inferior mesenteric, and inferior
Sympathetic postganglionic fibers
hypogastric ­plexuses distribution.
Parasympathetic preganglionic fibers
Parasympathetic postganglionic fibers
**Minimal sympathetic preganglionic fibers traveling
through the sacral splanchnic nerves will synapse in
Fig.the16.43
innervation
ganglia Autonomic
located in the inferior
hypogastric plexus.
Sympathetic
trunk
of the kidneys and upper ureters
Posterior
vagal trunk
Sympathetic
trunk
Lesser splanchnic n.
(T10-T11)
Posterior
vagal trunk
Aorticoren
ganglion
Lesser splanchnic n.
(T10-T11)
Kidney
Least splanchnic n.
(T12)
Aorticorenal
ganglion
First lumbar
splanchnic n.
Least splanchnic n.
(T12)
BZones of referred pain from
Renal
the left kidney and bladder.
First lumbar
splanchnic n.
ganglia
Renal
plexus
ASchematic of renal
and ureteral plexuses
distribution.
Urinary
bladder
Renal
ganglia
Sympathetic preganglionic fibers
Sympathetic postganglionic fibers
Parasympathetic preganglionic fibers
Parasympathetic postganglionic fibers
Ureteral
plexus
Renal
plexus
Ureteral
plexus
Sympathetic preganglionic fibers
Upper ureter
Sympathetic postganglionic fibers
Parasympathetic preganglionic fibers
Parasympathetic postganglionic fibers
215
Abdomen
Innervation of the Foregut & Urinary Organs
Fig. 16.44 Innervation of the foregut and spleen
Anterior view. Removed: Lesser omentum, ascending colon, and parts of
the transverse colon. Opened: Omental bursa. The anterior and poste­
rior vagal trunks each produce a celiac, hepatic, and pyloric branch, and
a gastric plexus. See p. 214 for schematic.
Posterior vagal trunk,
celiac br.
Anterior vagal trunk
Anterior
gastric plexus
Anterior
vagal trunk,
hepatic br.
Gastric plexus
(on left
gastric a.)
Posterior
vagal trunk,
hepatic br.
Splenic plexus
Anterior
vagal trunk,
pyloric br.
Left greater
splanchnic n.
Left lesser
splanchnic n.
Margin of
hepatoduodenal
lig.
Celiac ganglia
Hepatic plexus (on
common hepatic a.)
Brs. of
gastric plexus
(on gastro­
omental aa.)
Pancreatic
plexus
(on pancreatico­
duodenal aa.)
Superior
mesenteric
plexus
(on superior
mesenteric a.)
Clinical box 16.9
Organization of the enteric plexus
The enteric plexus is the portion of the autonomic nervous system that
specifically serves all the organs of the gastrointestinal tract. Located within
the wall of the digestive tube (intramural nervous system), it is subject to
both sympathetic and parasympathetic influences. Congenital absence of the
enteric plexus leads to severe disturbances of gastrointestinal transit (e.g.,
Hirschsprung disease). The enteric plexus has basically the same organization
throughout the gastrointestinal tract, although there is an area in the wall
of the lower rectum that is devoid of ganglion cells. Three subsystems are
distinguished in the enteric plexus:
• Submucosal plexus (Meissner’s plexus)
• Myenteric plexus (Auerbach’s plexus)
• Subserosal plexus
216
Muscularis externa,
longitudinal layer
Muscularis externa,
circular layer
Submucosa
Serosa
Mucosa
Subserosal
plexus
Myenteric
plexus
Submucosal
plexus
16 Neurovasculature
Fig. 16.45 Innervation of the urinary organs
Anterior view of the male abdomen and pelvis. Removed: Peritoneum,
majority of stomach, and abdominal organs except kidneys, suprarenal
glands, and bladder. See pp. 215 and 282 for schematic.
Right greater
splanchnic n.
Posterior
vagal trunk
Right lesser
splanchnic n.
Anterior
vagal trunk
Celiac ganglion
Suprarenal plexus
Renal plexus
Aorticorenal
ganglia
Superior mesen­
teric ganglion
Intermesenteric
plexus
Sympathetic trunk,
lumbar ganglia
Ureteral plexus
Inferior mesen­
teric ganglion
Testicular plexus
Inferior mesen­
teric plexus
Iliac plexus
Sympathetic trunk,
sacral ganglia
Right hypo­
gastric nn.
Pelvic splanchnic nn.
Vesical plexus
Superior hypo­
gastric plexus
Left hypo­
gastric n.
1st sacral n.,
anterior ramus
Inferior hypo­
gastric plexus
Middle rectal
plexus
Prostatic plexus
217
Abdomen
Innervation of the Intestines
Fig. 16.46 Innervation of the small intestine
Anterior view. Partially removed: Stomach, pancreas,
and transverse colon (distal part). See p. 215 for schematic.
Anterior vagal trunk,
hepatic br.
Right greater
splanchnic n.
Posterior
vagal trunk
Anterior
vagal trunk
Posterior vagal
trunk, celiac br.
Left greater
splanchnic n.
Hepatic plexus
Anterior
vagal trunk,
pyloric br.
Aorticorenal
ganglion
Superior mesen­
teric ganglion
Testicular
(ovarian) plexus
Right colic a.
(with autonomic
plexus)
Ileocolic a.
(with autonomic
plexus)
218
Celiac ganglia
Splenic plexus
Left lesser
splanchnic n.
Renal plexus
Superior
mesenteric
plexus
Jejunal and ileal aa.
(with autonomic
plexuses)
16 Neurovasculature
Fig. 16.47 Innervation of the large intestine
Anterior view. Removed: Small intestine.
Reflected: Transverse and sigmoid colons. See p. 215 for schematic.
Transverse
colon
Middle and right
colic aa. (with
autonomic
plexuses)
Intermesenteric
plexus
Ileocolic a. (with
autonomic plexus)
Left colic a.
(with autonomic
plexus)
Descending
colon
Inferior mesen­
teric ganglion
Inferior mesen­
teric plexus
Ascending colon
Superior hypo­
gastric plexus
Right hypo­
gastric nn.
Superior
rectal a. (with
autonomic plexus)
Sigmoid aa.
(with autonomic
plexus)
Inferior hypo­
gastric plexus,
brs. to
descending
colon and
sigmoid colon
219
17
Sectional & Radiographic Anatomy
Abdomen
Sectional Anatomy of the Abdomen
Fig. 17.1 Transverse sections
of the abdomen
Inferior view.
Parietal
peritoneum
Falciform lig. of liver
Common
hepatic a.
Visceral
peritoneum
Liver,
left lobe
Liver,
right lobe
Diaphragm,
costal part
Gallbladder
Splenic a.
Portal v.
Stomach
Lumbar l.n.
(preaortic)
Inferior
vena cava
Abdominal
aorta
Left suprarenal
gland
Right suprarenal gland
Left kidney
Left colic
flexure
Diaphragm,
costal part
T12 vertebra
Spleen
Vertebral canal
with spinal cord
A
Section through T12 vertebra.
Internal
thoracic
Transverse
a. and v. Duodenum
colon
Common
bile duct
Greater
omentum
Pyloric part
Superior
mesenteric
a. and v.
Anterior
wall
Gallbladder
Liver,
right lobe
Posterior
wall
Inferior
vena cava
Intercostal
v., a., and n.
Omental
bursa
Intermediate
lumbar l.n.
Splenic v.
Pancreas
Right suprarenal
gland
Spleen
Kidney
(with right
renal a.)
Transverse
colon
Descending colon
Abdominal
L1 vertebra
aorta
220
BSection through L1 vertebra.
Stomach
Spinal cord
(in vertebral canal)
Vertebral
venous plexus
Lateral
lumbar l.n.
Perirenal
fat capsule
Left kidney
Left
colic
flexure
Pancreas, Superior mesenteric
a. and v.
head
Stomach,
body
Jejunal a.
Celiac l.n.
Duodenum,
descending part
Transverse
mesocolon
Gallbladder
Jejunum
17 Sectional & Radiographic Anatomy
Transverse
colon
Descending
colon
Duodenojejunal
flexure
Liver
Right kidney
C
Section through L2 vertebra.
Psoas
major
Inferior
vena cava
Spinal
cord
Abdominal
aorta
Ureter
221
Abdomen
Radiographic Anatomy of the Abdomen (I)
Fig. 17.2 CT of the abdomen:
Transverse sections
(Reproduced from Moeller TB,
Reif E. Pocket Atlas of Sectional
Anatomy, Vol 2, 4th ed. New
York, NY: Thieme; 2014.)
Jejunum
Gallbladder
Stomach (pylorus)
Portal vein (right br.)
Liver (right lobe)
A
B
C
Portal v.
Inferior vena cava
Right suprarenal
gland
A
Transverse section through
T12 vertebral level
Abdominal aorta
in aortic hiatus
Descending colon
Pancreas (body)
Splenic a.
Common hepatic a.
Spleen
Splenic a. and v.
Diaphragm (lumbar
part, left crus)
Transverse colon
Duodenum
Pancreas (head)
Portal v. (confluence)
Jejunum
Splenic v.
Pancreas (tail)
Right hepatic v.
Inferior vena cava
Celiac trunk
Abdominal aorta
Right suprarenal gland and
(superior) suprarenal a.
Left lung (costodiaphragmatic recess)
B
Transverse section through
L1 vertebral level
Liver (right lobe)
Duodenum
(descending part)
Right renal a. and v.
Abdominal aorta
Right kidney (renal
pyramid, medulla)
Psoas major muscle
C
Transverse section through
L2 vertebral level
222
Left kidney (superior pole)
Superior mesenteric
a. and v.
Pancreas (head)
Descending colon
Duodenum (ascending part)
Inferior mesenteric v.
Left renal v.
Left kidney (hilum)
Inferior vena cava
Ileocolic a. and v.
D
E
F
Liver (right lobe)
Duodenum
(horizontal part)
Right kidney (pelvis)
Inferior vena cava
Root of mesentery
Superior mesenteric
a. and v.
Jejunum
Posterior paracolic
space
Abdominal aorta
Psoas major muscle
Quadratus lumborum
muscle
DTransverse section through
L3 vertebral level
Posterior pararenal
space
Spinal canal with
cauda equina
17 Sectional & Radiographic Anatomy
Small intestine
Umbilicus
Right testicular
a. and v.
Rectus abdominis
muscle
External oblique muscle
Internal oblique muscle
Transverse abdominis muscle
Right kidney (renal
pyramid, medulla)
Abdominal aorta
Inferior vena cava
Right ureter
E
Transverse section through
L4 vertebral level
Small intestine
Ascending colon
Anterior superior
iliac crest
Iliacus muscle
Wing of ilium
(superior border)
Gluteus medius muscle
F
Transverse section through
L5 vertebral level
Lumbar plexus
Descending colon
Common iliac arteries
Psoas major muscle
Inferior vena cava
(confluence)
223
Abdomen
Radiographic Anatomy of the Abdomen (II)
Fig. 17.3 CT of the abdomen:
Sagittal section through the aorta
(Reproduced from Moeller TB, Reif E. Pocket
Atlas of Sectional Anatomy, Vol 2, 4th ed.
New York, NY: Thieme; 2014.)
Heart
Liver (left lobe)
Stomach
Pancreas
Celiac trunk
Transverse colon
Superior
mesenteric a.
Jejunum
Right renal v.
Lumbar vertebral
body (L2)
Abdominal aorta
Duodenum
(horizontal part)
Promontory
of sacrum
Rectum
Urinary bladder
Fig. 17.4 CT of the Abdomen:
Coronal section through the kidneys
(Reproduced from Moeller TB, Reif E. Pocket
Atlas of Sectional Anatomy, Vol 2, 4th ed. New
York, NY: Thieme; 2014.)
Stomach (fundus)
Liver (right lobe)
Inferior vena cava
Right kidney, superior
pole, and right renal a.
Renal pelvis
Psoas muscle
Spleen with splenic
a. and v.
Pancreas (tail)
Left renal v. and a.
Left kidney (renal cortex)
Inferior mesenteric v.
Iliacus muscle
Gluteus medius
muscle
Fig. 17.5 Radiograph of intravenous
pylegram
12th rib
Anterior view.
Common iliac
a. and v. (left)
Major calyces
Renal pelvis
Right
ureter
Inferior pole
of left kidney
Distal ureter
Urinary
bladder
224
Fig. 17.6 Radiographs of double contrast
barium enema.
Anterior view.
Jejunum
Left
colic
flexure
Right colic
flexure
Transverse
colon
Colonic
haustra
Ascending
colon
Descending
colon
17 Sectional & Radiographic Anatomy
Circular folds
Sacrum
Cecum
Ilium
Sigmoid
colon
Ileum
A
Small intestine. (Reproduced courtesy of Universitätsmedizin
Mainz, Klinik und Poliklinik für Diagnostische und Interventionelle Radiologie.)
B
Large intestine. (Reproduced courtesy of Klinik für Diagnostische Radiologie, Universitätsklinikum Schleswig Holstein, Campus Kiel: Prof. Dr. Med. S. Müller-Huelsbeck.)
Fig. 17.7 MRI of the intestines
Coronal view. Sectional imaging modalities like CT and MR have mostly
replaced conventional radiographs in the evaluation of gastrointestinal
disease. (Reproduced from Krombach GA, Mahnken AH. Body Imaging:
Thorax and Abdomen. New York, NY: Thieme; 2018.)
TC
TC
TC
*
AC
DC
BB
A Jejunum (arrow)
B
Ileum (arrow), transverse colon (TC),
urinary bladder (B)
C
Ascending colon (AC), descending colon
(DC), transverse colon (TC), * small bowel
and mesenteric structures.
225
Pelvis & Perineum
22 Neurovasculature
18 Surface Anatomy
Surface Anatomy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 228
19 Bones, Ligaments & Muscles
Pelvic Girdle. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Female & Male Pelvis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Female & Male Pelvic Measurements . . . . . . . . . . . . . . . . . . .
Pelvic Ligaments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Muscles of the Pelvic Floor & Perineum . . . . . . . . . . . . . . . . .
Pelvic Floor & Perineal Muscle Facts. . . . . . . . . . . . . . . . . . . .
230
232
234
236
238
240
20 Spaces
268
270
272
274
276
278
280
282
284
23 Sectional & Radiographic Anatomy
Contents of the Pelvis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 242
Peritoneal Relationships . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 244
Pelvis & Perineum . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 246
21 Internal Organs
Rectum & Anal Canal. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Ureters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Urinary Bladder & Urethra . . . . . . . . . . . . . . . . . . . . . . . . . . .
Overview of the Genital Organs . . . . . . . . . . . . . . . . . . . . . . .
Uterus & Ovaries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Ligaments & Fascia of the Deep Pelvis . . . . . . . . . . . . . . . . . .
Vagina . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Female External Genitalia . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Penis, Testis & Epididymis . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Male Accessory Sex Glands. . . . . . . . . . . . . . . . . . . . . . . . . . .
Overview of the Blood Supply to Pelvic Organs & Wall . . . . .
Arteries & Veins of the Male Pelvis . . . . . . . . . . . . . . . . . . . . .
Arteries & Veins of the Female Pelvis . . . . . . . . . . . . . . . . . . .
Arteries & Veins of the Rectum & External Genitalia . . . . . . .
Lymphatics of the Pelvis . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Lymph Nodes of the Genitalia. . . . . . . . . . . . . . . . . . . . . . . . .
Autonomic Innervation of the Genital Organs. . . . . . . . . . . .
Autonomic Innervation of the Urinary Organs
& Rectum. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Neurovasculature of the Male & Female Perineum . . . . . . . .
248
250
252
254
256
258
260
262
264
266
Sectional Anatomy of the Pelvis & Perineum. . . . . . . . . . . . . 286
Radiographic Anatomy of the Female Pelvis. . . . . . . . . . . . . 288
Radiographic Anatomy of the Male Pelvis . . . . . . . . . . . . . . . 290
18
Surface Anatomy
Pelvis & Perineum
Surface Anatomy
Fig. 18.1 Palpable structures of the pelvis
Anterior view. The structures are common to both male
and female. See pp. 2–3 for structures of the back.
Transumbilical
plane
(L3–4 disk)
Anterior superior
iliac spine (ASIS)
Inguinal lig.
Pubic symphysis
Pubic tubercle
A
Bony prominences, female pelvis.
Anterior superior
iliac spine (ASIS)
Superficial
inguinal ring
Sartorius
Quadriceps
femoris
B
Musculature, male pelvis.
228
The perineum is the inferiormost portion of the trunk, between the
thighs and buttocks, extending from the pubis to the coccyx and
superiorly to the inferior fascia of the pelvic diaphragm, including all
of the structures of the anal and urogenital triangles (Fig. 18.2A). The
bilateral boundaries of the perineum are the pubic symphysis, ischio­
pubic ramus, ischial tuberosity, sacrotuberous ligament, and coccyx.
18 Surface Anatomy
Fig. 18.2 Regions of the female perineum
Lithotomy position.
Prepuce
of clitoris
Mons
pubis
Glans of clitoris
Labium minus
External urethral
orifice
Vagina
(vaginal orifice)
Ischiopubic ramus
Posterior labial
commissure
Labium majus
Urogenital
triangle
Ischial
tuberosity
Anal triangle
Perineal
region
Perineal
raphe
Coccyx
Ischial
spine
Anus
Posterior
commissure
of vagina
Sacrum
A
Perineal region.
B
Surgical
gynecological
perineum.
Lateral crease
of thigh
Surgical
gynecological
perineum
Anterior
border of
anus
Fig. 18.3 Regions of the male perineum
Lithotomy position.
Pubic
symphysis
Scrotum
Penis
Glans of penis
Perineal raphe
Ischiopubic
ramus
Urogenital
triangle
Ischial
tuberosity
Anal triangle
Perineal
region
Anus
Coccyx
Ischial
spine
A
Perineal region.
Surgical
perineum
Sacrum
B
Surgical perineum.
Posterior
border of
root of
scrotum
Lateral crease
of thigh
Anterior
border
of anus
229
19
Bones, Ligaments & Muscles
Pelvis & Perineum
Pelvic Girdle
The pelvis is the region of the body inferior to the abdomen and
surrounded by the pelvic girdle, which is the two coxal (hip) bones and
the sacrum that connect the vertebral column to the femur. The two
coxal bones are connected to each other at the cartilaginous pubic
symphysis and to the sacrum via the sacroiliac joints, creating the pelvic
brim (red, Fig. 19.1). The stability of the pelvic girdle is necessary for
the transfer of trunk loads to the lower limb, which occurs in normal
gait.
Fig. 19.1 Pelvic girdle
Fig. 19.2 Coxal bone
Anterosuperior view. The pelvic girdle consists of the two coxal bones and the sacrum.
Sacroiliac
joint
Right side (male).
Coxal bone
Iliac crest
Pubic
symphysis
Iliac fossa
Iliac
tuberosity
Anterior
superior
iliac spine
Auricular
surface of
ilium
Arcuate
line
Sacrum
Anterior
inferior
iliac spine
Ischial
spine
Acetabular
rim
Pectineal
line
Acetabulum
Iliac crest
Iliac
tuberosity
Iliac fossa
Posterior
superior
iliac spine
Anterior
superior
iliac spine
Auricular
surface
of ilium
Posterior inferior
iliac spine
Anterior
inferior
iliac spine
Arcuate line
Ilium,
body
Superior
pubic ramus
Ischial spine
Pectineal
line
Ischial
tuberosity
A
Anterior view.
Pubis,
body
Pubic
tubercle
Ischium,
body
Symphyseal
surface
Inferior
pubic ramus
230
Obturator
foramen
Obturator
foramen
Ischial
ramus
Ischial
tuberosity
B
Medial view.
Symphyseal
surface
Fig. 19.3 Triradiate cartilage of the coxal bone
Right coxal bone, lateral view. The coxal bone consists of the ilium,
ischium, and pubis.
Iliac crest
Ilium
Ilium,
body
Acetabulum
Pubis,
body
Superior
pubic ramus
Ischial spine
Ischium
Triradiate
cartilage
Acetabulum
Pubis
Inferior
pubic ramus
Ischium,
body
19 Bones, Ligaments & Muscles
Iliac wing
Ischial
ramus
Ischial
tuberosity
Obturator
foramen
A
Junction of the triradiate cartilage.
B
Radiograph of a child’s acetabulum.
Fig. 19.4 Coxal bone
Right side (male), lateral view.
Anterior
gluteal line
Iliac crest
Posterior
gluteal line
Gluteal surface
Anterior superior
iliac spine
Posterior
superior
iliac spine
Inferior
gluteal line
Anterior inferior
iliac spine
Posterior
inferior
iliac spine
Acetabular rim
Greater
sciatic notch
Lunate surface
Acetabular fossa
Acetabulum
Acetabular notch
Ischial spine
Lesser
sciatic notch
Pubic
tubercle
Obturator
foramen
Ischial
tuberosity
231
Pelvis & Perineum
Female & Male Pelvis
Fig. 19.5 Female pelvis
Pubic
tubercle
Sacroiliac
joint
Iliac crest
Iliac fossa
Sacrum
Anterior superior
iliac spine
Anterior inferior
iliac spine
Superior
and inferior
pubic rami
Acetabular
margin
Ischial spine
Pubic symphysis
Obturator
foramen
Coccyx
Pubic arch
A
Anterior view.
Ischial ramus
Iliac
crest
Sacral canal
Iliac wing
Posterior
superior
iliac spine
Median
sacral crest
Greater
sciatic notch
Posterior
inferior
iliac spine
Superior
pubic ramus
Lesser
sciatic notch
Ischial
tuberosity
Ischial spine
Inferior
pubic ramus
Sacroiliac
joint
Iliac
tuberosity
Sacral
hiatus
B
Posterior view.
Sacral
canal
Promontory
Ala of sacrum
Iliac crest
Inner lip
Iliac
tubercle
Intermediate
line
Outer lip
Arcuate
line
Iliac fossa
Coccyx
Anterior
superior
and inferior
iliac spines
Ischial
spine
Pubic crest
C
Superior view.
232
Pubic
tubercle
Pectineal line
(pecten pubis)
Clinical box 19.1
Childbirth
A non-optimal relation between the maternal pelvis
and the fetal head may lead to complications during
childbirth, potentially necessitating a caesarean
section. Maternal causes include earlier pelvic trauma
and innate malformations. Fetal causes include
hydrocephalus (disturbed circulation of cerebrospinal
fluid, leading to brain dilation and cranial expansion).
Fig. 19.6 Male pelvis
Sacrum
Superior
articular
process
Pelvic
surface
19 Bones, Ligaments & Muscles
Iliac crest
Ala
Promontory
Anterior
superior
and inferior
iliac spines
Posterior inferior
iliac spine
Anterior sacral
foramina
Pectineal line
(pecten pubis)
Pubic tubercle
Acetabulum
Ischial spine
Pubic symphysis
Obturator foramen
Pubic
arch
A
Anterior view.
Iliac crest
Illiac
tuberosity
Superior
articular process
Gluteal surface
Sacral
canal
Iliac
tubercle
Posterior
superior
and inferior
iliac spines
Median
sacral crest
Sacral hiatus
Posterior
sacral foramina
Acetabular
margin
Ischial spine
Pubis
B
Posterior view.
Inner lip
Iliac
crest
Intermediate
line
Median
sacral crest
Coccyx
Ischial tuberosity
Superior
articular process
Ala of
sacrum
Outer lip
Iliac fossa
Base of
sacrum
Arcuate
line
Ischial
spine
C
Superior view.
Anterior
superior
and inferior
iliac spines
Pectineal line
Pubic (pecten pubis)
symphysis
Iliopubic
eminence
233
Pelvis & Perineum
Female & Male Pelvic Measurements
The pelvic inlet, the superior aperture of the pelvis, is the boundary
between the abdominal and pelvic cavities. It is defined by the plane
that passes through its edge, the pelvic brim, which is the prominence
of the sacrum, the arcuate and pectineal lines, and the upper margin of
the pubic symphysis. Occasionally, the terms pelvic inlet and pelvic brim
are used interchangeably. The pelvic outlet is the plane of the inferior
aperture, passing through the pubic arch, the ischial tuberosities, the
inferior margin of the sacrotuberous ligament, and the tip of the coccyx.
Female
Male
Table 19.1
Gender-specific features of the pelvis
Structure
♀
♂
False pelvis
Wide and shallow
Narrow and deep
Pelvic inlet
Transversely oval
Heart-shaped
Pelvic outlet
Roomy and round
Narrow and oblong
Ischial tuberosities
Everted
Inverted
Pelvic cavity
Roomy and shallow
Narrow and deep
Sacrum
Short, wide, and flat
Long, narrow, and convex
Subpubic angle
90–100 degrees
70 degrees
Pubic
symphysis
Subpubic
angle
A
Male vs. female pelvis.
B Female.
C
Male.
Fig. 19.7 True and false pelvis
The pelvis is the region of the body inferior to the abdomen, surrounded
by the pelvic girdle. The false pelvis is immediately inferior to the abdominal cavity, between the iliac alae, and superior to the pelvic inlet.
The true pelvis is the bony-walled space between the pelvic inlet and the
pelvic outlet. It is bounded inferiorly by the pelvic diaphragm, also called
the pelvic floor.
Plane of
pelvic inlet
Plane of
pelvic inlet
Symphyseal
surface
Plane of
pelvic outlet
A
Female. Midsagittal section,
viewed from left side.
234
Coccyx
Symphyseal
surface
Plane of
pelvic outlet
B
Male. Midsagittal section,
viewed from left side.
Coccyx
The true conjugate, the distance between the promontory and the
most posterosuperior point of the pubic symphysis, is the narrowest AP
(anteroposterior) diameter of the pelvic (birth) canal. This diameter is
difficult to measure due to the viscera, so the diagonal conjugate, the
distance between the promontory and the inferior border of the pubic
symphysis, is used to estimate it. The linea terminalis is part of the
border defining the pelvic inlet (pelvic brim).
Diagonal
conjugate
True
conjugate
Linea
terminalis
Plane of
pelvic inlet
Plane of
pelvic outlet
~60°
19 Bones, Ligaments & Muscles
Fig. 19.8 Narrowest diameter of female pelvic canal
~15°
Fig. 19.9 Pelvic inlet and outlet
The measurements shown are applicable to both male and female.
The transverse and oblique diameters of the female pelvic inlet are
obstetrically important, as they are the measure of the diameter of
the pelvic (birth) canal. The interspinous distance is the narrowest
diameter of the pelvic outlet.
Interspinous
diameter
Right
oblique
diameter
Transtubercular
distance
Left
oblique
diameter
Transverse
diameter of
pelvic inlet plane
Interspinous
distance
Linea
terminalis
Pelvic inlet plane
Pelvic inlet plane
A
Female pelvis, superior view.
Pelvic inlet outlined in red.
Pubic
symphysis
B
Male pelvis, superior view.
Pelvic inlet outlined in red.
Superior
pubic
ramus
Superior
pubic
ramus
Inferior
pubic
ramus
Pubic
symphysis
Ischial
ramus
Ischial
tuberosity
Coccyx
Coccyx
C
Female pelvis, inferior view.
Pelvic outlet outlined in red.
DMale pelvis, inferior view.
Pelvic outlet outlined in red.
235
Pelvis & Perineum
Pelvic Ligaments
Fig. 19.10 Ligaments of the pelvis
Sacral
promontory
Male pelvis.
Anterior longitudinal
lig.
Iliolumbar lig.
Anterior
sacroiliac
ligs.
Sacrotuberous
lig.
Anterior
superior iliac
spine
Inguinal lig.
Anterior inferior
iliac spine
Sacrospinous lig.
Coccyx
Ischial spine
Pectineal lig.
Pubic symphysis
Pubic
tubercle
Obturator
membrane
A
Anterosuperior view.
L4 spinous process
Iliac crest
Iliolumbar lig.
Iliac tubercle
Ilium, gluteal
surface
Posterior superior
iliac spine
Short posterior
sacroliac ligs.
Posterior
sacroiliac ligs.
B
Posterior view.
On the right, the
superficial part
of the posterior
sacroiliac ligament
has been removed
to reveal long and
short posterior
sacroiliac ligaments
which blend with the
deeper interosseous
sacroiliac ligament.
236
Posterior inferior
iliac spine
Greater sciatic
foramen
Long posterior
sacroiliac lig.
Sacrospinous
lig.
Lesser sciatic
foramen
Sacrotuberous
lig.
Ischial spine
Obturator
membrane
Coccyx
Ischial
tuberosity
Fig. 19.11 Ligaments of the sacroiliac joint
Fig. 19.12 Pelvic ligament attachment
sites on the coxal bone
Male pelvis, midsagittal section.
Intervertebral
disk L4/5
L5 spinous
process
Interosseous
sacroiliac
lig.
Sacrum
Promontory
Anterior superior
iliac spine
Sacral canal
Sacrospinous
lig.
Anterior
sacroiliac
lig.
Greater sciatic
foramen
Arcuate line
Sacrospinous
lig.
Pectineal line
Sacral hiatus
19 Bones, Ligaments & Muscles
Left coxal bone, medial view. Ligament attachments are shown in green.
Sacrotuberous
lig.
Pubic
symphysis
Ischial spine
Coccyx
Sacrotuberous
lig.
Obturator
canal
Lesser sciatic
foramen
Symphyseal
surface
Obturator
membrane
Ischial
tuberosity
A
Right half of pelvis, medial view.
Posterior superior
iliac spine
Sacrum
Sacral
canal
Iliac tuberosity
Posterior
sacroiliac
lig.
Interosseous
sacroiliac lig.
Anterior sacral
foramina
Sacral
tuberosity
Anterior
sacroiliac
lig.
Sacroiliac joint
Sacrospinous
lig.
Ischial
spine
Sacrotuberous
lig.
Ilium
Greater sciatic foramen
Coccyx
Anterior
sacrococcygeal
lig.
Lesser sciatic foramen
Acetabulum
Pubic
symphysis
B
Oblique section, superior view.
237
Pelvis & Perineum
Muscles of the Pelvic Floor & Perineum
Fig. 19.13 Muscles of the pelvic floor
Rectal hiatus
Urogenital hiatus
Prerectal fibers
Puborectalis
Obturator canal
Levator
ani
Pubococcygeus
Obturator fascia
(obturator internus)
Iliococcygeus
Ischial spine
Tendinous arch
of levator ani
Coccygeus
Piriformis
Anococcygeal
raphe
A
Superior view.
Pubic
symphysis
Inferior pubic
lig.
Sacrum
Prerectal fibers
Obturator
internus
Urogenital
hiatus
Puborectalis
Pubococcygeus
Iliococcygeus
Acetabulum
Ischial
tuberosity
Levator
ani
Piriformis
Rectal hiatus
Coccyx
Coccygeus
B
Inferior view.
Anterior sacroiliac lig.
Arcuate line
Piriformis
Coccygeus
Obturator
internus fascia
Posterior
superior
iliac spine
Ischial spine
Tendinous arch
of levator ani
Anococcygeal lig.
Pubic symphysis
Piriformis
Coccygeus
Sacrospinous lig.
Pubic tubercle
Sacrotuberous lig.
Obturator
foramen
Coccyx
Ischial spine
DRight lateral view.
238
Levator ani
Deep transverse
perineal
C
Medial view of right hemipelvis.
Iliococcygeus
Pubococcygeus
Puborectalis
Levator
ani
Fig. 19.14 Muscles and fascia of the pelvic
floor and perineum, in situ
Bulbospongiosus
Ischiocavernosus
Superficial
perineal
(Colles’) fascia
Perineal membrane
Perineal body
Superficial transverse
perineal
Ischial
tuberosity
Obturator internus
Obturator
fascia
Gluteus maximus
Inferior fascia
of pelvic
diaphragm
Levator ani
Anococcygeal
lig.
A
Female.
19 Bones, Ligaments & Muscles
Lithotomy position. Removed on left side: Superficial
perineal (Colles’) fascia, inferior fascia of the pelvic
diaphragm, and obturator fascia.
Note: The green arrows are pointing forward to the
anterior recess of the ischioanal fossa.
Coccyx
External anal
sphincter
Anal cleft
Bulbospongiosus
Ischiocavernosus
Superficial
perineal
(Colles’) fascia
Perineal membrane
Ischial
tuberosity
Superficial transverse
perineal
Obturator
fascia
Obturator internus
Gluteus maximus
Inferior fascia
of pelvic
diaphragm
Levator ani
Anococcygeal
lig.
B
Male.
External anal
sphincter
Anococcygeal
lig.
Fig. 19.15 Genderrelated differences
in structure of the
levator ani
Posterior view. Note the
connective tissue gaps
­between muscular parts of
the levator ani in the female.
Levator
ani
A
Male.
B Female.
External
anal sphincter
Connective
tissue gaps
239
Pelvis & Perineum
Pelvic Floor & Perineal Muscle Facts
Fig. 19.16 Muscles of
the pelvic floor
Superior view.
Iliococcygeus
②
①
Obturator
internus
Anococcygeal
lig.
③
④
A
Muscles of the
pelvic diaphragm.
Coccygeus
Piriformis
B
Outermost layer
of the pelvic floor.
Muscles of the pelvic floor
Table 19.2
Muscle
Origin
Insertion
Innervation
Action
Superior pubic ramus (both
sides of pubic symphysis)
Anococcygeal lig.
Nerve to levator ani
(S4), inferior rectal n.
Pelvic diaphragm: Supports pelvic viscera
Ischial spine
Direct branches from
sacral plexus (S4–S5)
Supports pelvic viscera, flexes coccyx
Muscles of the pelvic diaphragm
① Puborectalis
Levator ani
Pubis (lateral to origin of
② Pubococcygeus puborectalis)
③ Iliococcygeus
Anococcygeal lig., coccyx
Internal obturator fascia of
levator ani (tendinous arch)
Lateral surface of coccyx and
S5 segment
④ Coccygeus
Muscles of the pelvic wall (parietal muscles)
Piriformis*
Sacrum (pelvic surface)
Femur (apex of greater
trochanter)
Direct branches from
sacral plexus (S1–S2)
Hip joint: External rotation, stabilization,
and abduction of flexed hip
Obturator internus*
Obturator membrane and bony
boundaries (inner surface)
Femur (greater trochanter,
medial surface)
Direct branches from
sacral plexus (L5–S1)
Hip joint: External rotation and abduction
of flexed hip
*The piriformis and obturator internus are considered muscles of the hip (see p. 426).
The female and male external genitalia are shown on pp. 262–265.
Fig. 19.17 Muscles of the perineum
Inferior view.
Bulbospongiosus
Bulbospongiosus
Ischiocavernosus
Ischiocavernosus
Perineal
membrane
Urethrovaginal
sphincter
Superficial
transverse
perineal
Perineal
membrane
Deep transverse
perineal
Deep transverse
perineal
Superficial
transverse
perineal
External anal
sphincter
A
Superficial and deep perineal
muscles in the male.
240
External urethral
sphincter
Compressor
urethrae
B
Superficial and deep perineal
muscles in the female.
Table 19.3
Muscles of the perineum
Origin
Insertion
① Ischiocavernosus
Ischial ramus
Crus of clitoris or penis
② Bulbospongiosus
Runs anteriorly from perineal body to clitoris (females) or
penile raphe (males)
③ Superficial transverse
Innervation
Action
Maintains erection by squeezing blood
into corpus cavernosum of clitoris or
penis
Females: Compresses greater vestibular
gland
Males: Assists in erection
Helps hold perineal body in median
plane, holds the pelvic organs in place,
and supports visceral canals through the
muscles of the perineum
Ischiopubic ramus
Perineal body
④ Deep transverse perineal*
Ishiopubic ramus
Perineal body and external
anal sphincter
⑤ External urethral sphincter
Encircles urethra (division of deep transverse perineal muscle),
in males ascends anteriorly to neck of the bladder; in females,
some fibers surround the vagina as the urethrovaginal
sphincter, others extend laterally as the compressor urethrae
(See Figs. 21.9 and 21.11)
Closes urethra
⑥ External anal sphincter
Encircles anus (runs posteriorly from perineal body to
anococcygeal lig.)
Closes anus
perineal
Pudendal n. (S2–S4)
19 Bones, Ligaments & Muscles
Muscle
* Typically, this muscle is not developed in females and is replaced by smooth muscle tissue. When developed, it provides dynamic support to the pelvic organs.
Fig. 19.19 Muscles of the
female perineum
Fig. 19.18 Muscles of the
male perineum
②
①
①
③
③
⑥
A
Muscles of the superficial pouch in
the male.
②
⑥
A
Muscles of the superficial pouch in
the female.
Compressor
urethrae
⑤
⑤
④
④
Urethrovaginal
sphincter
B
Muscles of the deep pouch in the male.
B Muscles of the deep pouch in the female.
241
20
Spaces
Pelvis & Perineum
Contents of the Pelvis
Fig. 20.1 Male pelvis
Parasagittal section, viewed from the right side.
Right common
iliac a. and v.
Sigmoid
mesocolon
Tenia coli
L5 vertebra
Sigmoid colon
Parietal
peritoneum
Right ductus
deferens
Rectus
abdominis
Rectovesical
pouch
Visceral
peritoneum
on bladder
Visceral
peritoneum
on rectum
Rectum
Visceral
pelvic fascia
on bladder
Visceral
pelvic fascia
on rectum
Superior
pubic ramus
Right
ureter
Urinary bladder
Inferior pubic
ramus
Levator ani
Ischiocavernosus
Right seminal
gland
Prostate
External anal
sphincter
Bulbospongiosus
Anus
242
Perineal
body
Rectoprostatic
fascia
20 Spaces
Fig. 20.2 Female pelvis
Parasagittal section, viewed from the right side.
Right common iliac
a. and v.
Sigmoid
mesocolon
Tenia coli
L5 vertebra
Sigmoid colon
Uterine tube
Lig. of ovary
Round lig.
of uterus
Uterus
Vesicouterine
pouch
Rectouterine
pouch
Visceral
peritoneum
on rectum
Visceral
peritoneum
on bladder
Rectum
Visceral
pelvic fascia
on bladder
Visceral
pelvic fascia
on rectum
Superior
pubic ramus
Right ureter
Urinary bladder
Levator
ani
Inferior
pubic ramus
External
anal sphincter
Anus
Perineal
body
Vagina
Ischiocavernosus
243
Pelvis & Perineum
Peritoneal Relationships
Fig. 20.3 Peritoneal relationships
in the pelvis: Female
Broad lig.
of uterus
Rectum
Rectouterine Rectouterine
pouch
fold
Suspensory
lig. of ovary
Superior view.
Uterine
tube
Left ovary
Cecum
Sigmoid
colon
Fundus of
uterus
Lig. of
ovary
Parietal
peritoneum
Paravesical
fossa
Round lig.
of uterus
Deep inguinal
ring
Vesicouterine
pouch
Transverse
vesical fold
A
Lesser pelvis, anterosuperior view.
Retracted: Small intestine loops and
colon (portions).
Fundus of uterus
Rectum
Lateral umbilical
fold (with inferior
epigastric a. and v.)
Urinary
bladder
Rectus
abdominis
Median umbilical
fold (with obliterated
urachus)
Supravesical
fossa
Medial umbilical fold
(with obliterated
umbilical a.)
External iliac a. and v.
Peritoneum,
parietal layer
Cardinal lig.
Obturator
internus
Obturator
fascia
Levator ani
Superior and
inferior fascia
of pelvic
diaphragm
Ischioanal fossa,
anterior recess
Perineal
membrane
Deep transverse
perineal
Vagina
Superficial
perineal fascia
B
Muscles (red) of the pelvic floor.
Coronal section, anterior view.
Vesicouterine
pouch
Urinary bladder
Rectovaginal
septum
Retropubic
space
Peritoneal and subperitoneal spaces
C
(green) in the pelvis. Midsagittal
section, viewed from the left side.
244
Perineal
body
Sigmoid
colon
Uterus
Rectouterine
pouch
Retrorectal
(presacral)
space
Rectum
Ileum
Rectum
Rectovesical
pouch
20 Spaces
Fig. 20.4 Peritoneal relationships
in the pelvis: Male
Transverse
vesical fold
Superior view.
Cecum
Parietal
peritoneum
Ductus
deferens
Vermiform
appendix
Sigmoid
colon
Lateral inguinal
fossa
Lateral umbilical fold
(with inferior epigastric
a. and v.)
Urinary bladder
A
Lesser pelvis, anterosuperior view.
Retracted: Small intestine and
colon (portions).
Median umbilical fold
(with obliterated
urachus)
Urinary bladder
Rectus
abdominis
Medial umbilical fold
(with obliterated
umbilical a.)
Peritoneum,
parietal layer
Paravesical
space
Obturator
internus
Superior
and inferior
fascia
of pelvic
diaphragm
Levator ani
Ischioanal fossa,
anterior recess
External urethral
sphincter
Perineal
membrane
Prostate
Bulb of penis
Crus of penis
Inferior
pubic
ramus
B
Muscles (red) of the pelvic floor.
Coronal section, anterior view.
Peritoneal and subperitoneal spaces
C
(green) in the pelvis. Midsagittal section,
viewed from the left side.
Urinary
bladder
Rectovesical
septum
Retropubic
space
Perineal
body
Sigmoid
colon
Rectovesical
pouch
Retrorectal
(presacral)
space
Rectum
245
Pelvis & Perineum
Pelvis & Perineum
The pelvis is the region of the body inferior to the abdomen, surrounded
by the pelvic girdle. The false, or greater, pelvis is immediately inferior to
the abdominal cavity, between the iliac alae, and superior to the pelvic
inlet. The true, or lesser, pelvis is found between the pelvic inlet and the
pelvic outlet and extends inferiorly to the pelvic diaphragm (levator ani
and coccygeus ), a muscular sling attached to the boundaries of the
Table 20.1
Divisions of the pelvis and perineum
The levels of the pelvis are determined by bony landmarks (iliac alae and pelvic
inlet/brim). The contents of the perineum are separated from the true pelvis
by the pelvic diaphragm and two fascial layers.
pelvic outlet. The perineum is the inferior most portion of the trunk, between the thighs and buttocks, extending from the pubis to the coccyx
and superiorly to the pelvic diaphragm. The superficial perineal pouch
lies between the membranous layer of the subcutaneous tissue (Colles’
­fascia) and the perineal membrane. The deep perineal pouch lies between
the perineal membrane and the inferior fascia of the pelvic diaphragm.
Fig. 20.5 Pelvis and urogenital triangle
Peritoneum
Uterus Vagina
Iliac crest
• Ileum (coils)
• Cecum and appendix
False pelvis
• Sigmoid colon
• Common and external iliac aa. and vv.
• Lumbar plexus (brs.)
Pelvic inlet
• Distal ureters
Pelvis
• Urinary bladder
• Rectum
♀: Vagina, uterus, uterine tubes, and ovaries
True pelvis
♂: Ductus deferens, seminal gland, and
prostate
• Internal iliac a. and v. and brs.
Obturator
internus
Pelvic
diaphragm
(with fascia)
Deep pouch
Internal
pudendal
a. and v.,
pudendal n.
Inferior
pubic
ramus
Crus
of clitoris
and ischiocavernosus
Perineal
membrane
Vestibular
bulb and
bulbospongiosus
Vestibule
of vagina
Superficial
Skin
perineal
(Colles’) fascia
Superficial
pouch
A
Female. Oblique section.
• Sacral plexus
• Inferior hypogastric plexus
Pelvic diaphragm (levator ani & coccygeus)
• Sphincter urethrae and deep transverse
perineal mm.
Urinary
Peritoneum bladder Prostate
• Urethra (membranous)
• Vagina
Deep pouch
Superior
fascia
of pelvic
diaphragm
• Rectum
• Bulbourethral gland
• Ischioanal fossa
• Internal pudendal a. and v., pudendal n.
and brs.
Perineum
Perineal membrane
• Ischiocavernosus, bulbospongiosus, and
superficial transverse perineal mm.
Superficial
pouch
• Urethra (penile)
• Clitoris and penis
• Internal pudendal a. and v., pudendal n. and
branches
Superficial perineal (Colles’) fascia
Subcutaneous
perineal space
• Fat
Obturator
internus
Levator ani
Inferior
fascia
of pelvic
diaphragm
Perineal
membrane
Superficial
perineal
(Colles’)
fascia
Deep pouch
Crus of penis
and ischiocavernosus
Urethra,
spongy
part
B
Male. Coronal section.
Peritoneal cavity
Visceral pelvic fascia
Subperitoneal space
Parietal pelvic fascia
Skin
Ischioanal fossa
246
BulboBulb of
penis spongiosus
Superficial
pouch
Fig. 20.6 Pelvis: Oblique
section
Suspensory lig.
of ovary
Anterior view.
Right
ureter
Rectum
Fundus of
uterus
External iliac
a. and v.
20 Spaces
Iliacus
Ovary
Round lig.
of uterus
Uterine tube
Cardinal (transverse
cervical) lig.
Cervix of
uterus
Right ureter
Paravaginal
tissue (fascia)
Obturator
internus
Vagina
Ischioanal fossa,
anterior recess
Inferior pubic
ramus
Levator ani
Deep
transverse
perineal
A
Female. Oblique section.
Crus of clitoris (with
ischiocavernosus)
Superficial
perineal (Colles’) fascia
Urinary
bladder
Vestibule
of vagina
Internal urethral
orifice
Vestibular bulb (with
bulbospongiosus)
Ureteral
orifice
Paravesical
fossa
Gluteus
minimus
Femur, head
Venous
plexus
Obturator
internus
Seminal
colliculus
Prostate
Levator ani
Urethra,
membranous
part
Obturator
externus
Deep
transverse
perineal
Quadratus
femoris
Inferior
pubic ramus
Crus of penis
(with ischiocavernosus)
Adductor mm.
B
Male. Coronal section.
Superficial
perineal
(Colles’) fascia
Bulb of penis
(with bulbospongiosus)
Subcutaneous
perineal space
247
21
Internal Organs
Pelvis & Perineum
Rectum & Anal Canal
Fig. 21.1 Rectum: Location
Fig. 21.2 Closure of the rectum
Left lateral view. The puborectalis acts as a
muscular sling that kinks the anorectal junction. It functions in the maintenance of fecal
continence.
Sigmoid
colon
RLQ
Rectum
LLQ
Coccyx
A
Anterior view.
Pubococcygeus
Pubis
Ilium
Puborectalis
Sacrum
Pubis
Sacral
flexure
Ischium
Perineal
flexure
Rectum
Perineal
flexure
Left anterolateral view.
B
Fig. 21.3 Rectum in situ
Coronal section, anterior view of the female pelvis. The upper third
of the rectum is covered with visceral peritoneum on its anterior and
lateral sides. The middle third is covered only anteriorly and the lower
third is inferior to the parietal peritoneum.
External
iliac a. and v.
Rectum
Tenia
coli
Sigmoid
mesocolon
Sigmoid
colon
Ureter
Parietal
peritoneum
Rectouterine
(uterosacral) fold
Superior and
inferior fascia of
pelvic diaphragm
Obturator
internus
Pudendal n.
Levator ani
(pelvic
diaphragm)
Internal pudendal
a. and v.
External anal
sphincter
Perineal n.
Ischioanal
fossa
Internal anal
sphincter
248
Anal
canal
Transverse
rectal fold
Fig. 21.4 Rectum and anal canal
Coronal section, anterior view with the
anterior wall removed.
21 Internal Organs
Peritoneal covering
of rectum
Superior transverse
rectal fold
Middle transverse
rectal fold
Circular layer
Longitudinal
layer
Muscularis
externa
Parietal
peritoneum
Rectal ampulla
Superior fascia of
pelvic diaphragm
Inferior transverse
rectal fold
Levator ani
Anorectal junction
Inferior fascia of
pelvic diaphragm
Hemorrhoidal
plexus
Anal canal
Internal anal
sphincter
Deep part
Anal columns
External anal
sphincter
Superficial
part
Anal sinuses
Anal valves
Subcutaneous
part
Anal pecten
(white zone)
Corrugator
cutis ani
Anocutaneous
line
Anus
Table 21.1
Anocutaneous line
②
③
④
⑤
Regions of the rectum and anal canal
Region
Epithelium
① Rectum
Colon-like with crypts; simple
columnar with goblet cells
①
Anorectal
junction
Pectinate line
Subcutaneous
venous plexus
Perianal skin
② Columnar zone
Anal canal
Anal
canal
③ Anal pecten
④ Cutaneous zone
⑤ Perianal skin (pigmented)
Stratified squamous,
nonkeratinized
Stratified squamous,
keratinized with sebaceous
glands
Stratified squamous,
keratinized with sebaceous
glands, hairs, and
sweat glands
249
Pelvis & Perineum
Ureters
Fig. 21.5 Ureters in situ
Anterior view, male abdomen. Removed: Nonurinary organs and rectal
stump. The ureters descend along the posterior abdominal wall in the
retroperitoneal space. On each side, they enter the pelvis after crossing
the common iliac artery at its bifurcation into the external and internal
arteries.
Celiac trunk
Abdominal
aorta
Left middle
suprarenal a.
Left inferior phrenic
a. and v.
Left superior
suprarenal a.
Left suprarenal
gland and v.
Inferior vena cava
Right suprarenal
gland and v.
Left inferior
suprarenal a.
Left renal a. and v.
Right kidney
Superior
mesenteric a.
Left testicular
a. and v.
Perirenal
fat capsule
Left kidney
Ureteropelvic
junction
Ureter,
abdominal part
Inferior
mesenteric a.
Right testicular
a. and v.
Psoas major
Right common
iliac a.
Iliacus
Median sacral
a. and v.
Left internal
iliac a. and v.
Right internal
iliac a. and v.
Left superior
gluteal a.
Sacral plexus
Anterior trunk
of internal iliac
a. and v.
Left external iliac
a. and v.
Inferior epigastric
a. and v.
Right ductus
deferens
Rectum
Ureterovesical
junction
Urinary
bladder
250
Pubic
symphysis
Median umbilical
lig.
Ureter,
pelvic part
Fig. 21.6 Ureter in the male pelvis
Pubic symphysis
Superior view with peritoneum removed.
Pubis
Tendinous arch of levator ani
Pelvic diaphragm,
superior fascia
Pubovesical muscles
Bladder, body
Bladder, apex
Median
umbilical lig.
Right ductus deferens
Left ductus deferens
Tendinous arch
of pelvic fascia
Left ureter
Rectum with peritoneal
covering on anterior wall
Fig. 21.7 Ureter in
the female pelvis
Superior view.
The pelvic ureters pass
under the uterine artery
­approximately 2 cm
lateral to the cervix.
Transverse
vesical fold
Pubis
21 Internal Organs
Inferior (arcuate)
pubic lig.
Right
ureter
Pubis symphysis
Median
umbilical lig.
Medial umbilical fold (occluded
part of umbilical a.)
Vesicouterine
pouch
Parietal
peritoneum
Bladder, body
Left external iliac
a. and v.
Uterus, fundus
Round lig. of
uterus
Passage of left ureter
through broad
lig. of uterus
Uterus, posterior
surface
Left broad
lig. of uterus
Passage of right
ureter through broad
lig. of uterus
Left uterine
tube
Uterosacral fold (with
uterosacral lig.)
Left ovary
Left ovarian a.
and v. in ovarian
suspensory lig.
Right ureter
Left
ureter
Rectum
Sacral promontory
Rectouterine
pouch
Clinical box 21.1
Anatomical constrictions of the ureter
There are three normal anatomical constrictions where a pain-causing kidney
stone from the renal pelvis is apt to become lodged:
First constriction: narrowing of
the ureter as it passes over inferior
renal pole (abdominal part)
•Narrowing at the origin of the ureter from the renal pelvis (ureteropelvic
junction)
•Site where the ureter crosses over the external or common iliac vessels
•Passage of the ureter through the bladder wall (ureterovesical junction).
Possible constriction where
the testicular or ovarian vessels
pass anterior to the ureter
Occasionally a fourth constriction can be identified where the testicular or
ovarian artery and vein pass anterior to the ureter.
Second constriction:
ureter crosses over external
iliac vessels (pelvic part)
Third constriction:
ureter traverses the bladder
wall (intramural part)
251
Pelvis & Perineum
Urinary Bladder & Urethra
Fig. 21.8 Female urinary
bladder and urethra
Left common iliac
a. and v.
Suspensory lig. of ovary
(with ovarian a. and v.)
L5 vertebra
Right uterine
tube
Right ureter
Right external
iliac a. and v.
Right ovary and
lig. of ovary
Rectus abdominis
Fundus of uterus
Body of uterus
Round lig.
of uterus
Rectum
Cervix of uterus
Urinary bladder
Posterior
vaginal fornix
Anterior
vaginal fornix
Levator ani
Pubic
symphysis
Vagina
Clitoris
Urethra
External anal
sphincter
External urethral
orifice
Perineal membrane
A
Midsagittal section of pelvis, viewed
from the left side. Right hemipelvis.
Median
umbilical
lig.
Interureteral
fold
Urogenital
peritoneum
Left
ureter
Apex of
bladder
Fundus
of bladder
Visceral
pelvic fascia
Right ureter,
intramural part
Ureteral orifice
Neck of
bladder
Body of
bladder
Female
urethra
Bladder and urethra, left lateral view.
B
Urinary
bladder,
trigone
Mucosa
Detrusor m.
Adventitia
with visceral
pelvic fascia
Urinary
bladder, neck
Internal urethral
orifice with
bladder uvula
Orifices of
urethral glands
Fig. 21.9 Urethral sphincter
­mechanism in the female
External urethral
sphincter
Muscularis
CTrigone and urethra, coronal section,
­anterior view.
Vagina
Compressor
urethrae
Urethra
Urethrovaginal
sphincter
252
Mucosa with
longitudinal folds
Submucosa
Left ureter
Anterolateral view.
Urinary
bladder
Urinary bladder,
body
Urethra
Fig. 21.10 Male urinary bladder and urethra
Urinary
bladder
Rectovesical
pouch
Rectum
Rectovesical
septum
Retropubic space
Suspensory
lig. of penis
Ductus deferens,
ampulla
Penile fascia
Ejaculatory duct
21 Internal Organs
Pubic symphysis
Prostate
Penis, corpus
cavernosum
Bulbourethral
gland
External urethral
sphincter
Bulbospongiosus
Penis, corpus
spongiosum
Urethra, spongy
part
Scrotal septum
Prepuce
A
Midsagittal section of pelvis, viewed
from left side. Right hemipelvis.
Median
umbilical lig.
Urogenital
peritoneum
Ureteral
orifice
Interureteric
crest
Detrusor muscle
Left
ureter
Apex of
bladder
Fundus
of bladder
Visceral
pelvic fascia
Body of
bladder
Ampulla of
ductus deferens
Prostate
Male urethra
B
Bladder, urethra and prostate, left lateral
view.
Prostatic
utricle
Prostatic
urethra
Prostate
Ejaculatory
ducts
Openings of
ejaculatory ducts
Prostate
External urethral
sphincter
Seminal
colliculus
Neck of bladder,
internal urethral
orifice
Internal urethral
sphincter
Dilator
urethrae
Internal urethral
sphincter
Fundus of bladder,
trigone
C
Trigone, urethra and prostate, coronal
­section, anterior view.
Prostatic
urethra
Bulb of penis
Fig. 21.11 Urethral sphincter
­mechanism in the male
Lateral view.
253
Pelvis & Perineum
Overview of the Genital Organs
The genital organs can be classified topographically (external versus
internal) and functionally (Tables 21.2 and 21.3).
Table 21.2
Internal
genitalia
Female genital organs
Organ
Function
Ovary
Germ cell and hormone production
Uterine tube
Site of conception and transport organ for zygote
Uterus
Organ of incubation and parturition
Vagina (upper portion)
Organ of copulation and parturition
Vagina (vestibule)
Labia majora and minora
External
genitalia
Vulva
Clitoris
Right kidney
Accessory copulatory organ
Greater and lesser
vestibular glands
Production of mucoid secretions
Mons pubis
Protection of the pubic bone
Right ureter
Fig. 21.12 Female genital organs
Suspensory
lig. of ovary
Ovary
Right uterine tube
Uterine
tube
Right ovary
Uterus
Round lig.
of uterus
Vagina
Labia minora
Vestibule
A
Internal and external genitalia.
Glans and crus
of clitoris
Vestibular bulb
Greater vestibular
(Bartholin’s) gland
Uterus
Cervix of
uterus
Median umbilical
lig.
Vagina
Urinary
bladder
Ureteral
orifice
Clitoris
Urethra
Greater
vestibular
(Bartholin's)
gland
Labium majus
Labium minus
B
Urogenital system. Note: The female urinary and genital tracts are
functionally separate, though topographically close.
254
Male genital organs
Table 21.3
Function
Testis
Germ cell and hormone production
Epididymis
Storage reservoir for sperm
Ductus deferens
Accessory
sex glands
External
genitalia
21 Internal Organs
Internal
genitalia
Organ
Transport organ for sperm
Prostate
Seminal glands
Production of secretions (semen)
Bulbourethral gland
Penis
Copulatory and urinary organ
Urethra
Conduit for urine and semen
Scrotum
Coverings of the testis
Protection of testis
Right kidney
Fig. 21.13 Male genital organs
Inguinal
canal
Ureter
Urinary
bladder
Ductus
deferens
Ductus deferens,
ampulla
Seminal gland
Right ureter
Excretory
duct
Ejaculatory
duct
Bulbourethral
gland
Ductus deferens
Penis
Prostate
Median
umbilical lig.
Deep transverse
perineal
Ductus
deferens
Urethra
Epididymis
Ureteral orifice
Urinary
bladder
Seminal gland
Testis
Ejaculatory duct
Penis, corpus
cavernosum
A
Seminiferous structures.
Prostate
Penis, corpus
spongiosum
Bulbourethral
gland
Urethra,
spongy part
Bulb of penis,
corpus spongiosum
Glans of penis,
corpus spongiosum
Scrotum
Testis
Epididymis
B
Urogenital system. Note: The male urethra serves as a common
urinary and genital passage.
255
Pelvis & Perineum
Uterus & Ovaries
Fig. 21.14 The broad ligament
Peritoneal
covering
Regions of the broad ligament, sagittal ­section. The
uterus and ovaries are suspended by the broad ligament
of the uterus, which is composed of a double layer of
peritoneum, arranged as a combination of mesenteries:
the mesosalpinx, meso­varium, and mesometrium.
Uterine
tube
Mesosalpinx
Mesovarium
Ovary
Mesometrium
Germinal
epithelial
covering
Fig. 21.15 Ovary
Right ovary, posterior view.
Mesovarium
Mesovarial
margin
Uterine tube
Uterus,
posterior surface
Proper ovarian lig.
Uterine pole
Vascular pole
Ovarian suspensory lig.
Follicular stigma (bulge
from Graafian follicle)
Ovarian a. and v.
Mesometrium
Medial surface
Free margin
Fig. 21.16 Normal curvature and position of the uterus
Midsagittal section, left lateral view. The position
of the uterus can be described in terms of:
① Flexion, the angle between the longitudinal
cervical axis and the longitudinal uterine axis; the
normal position is anteflexion.
② Version, the angle between the l­ongitudinal
cervical axis and longitudinal vaginal axis; the
normal position is anteversion.
Endometrium
Longitudinal
uterine axis
(in uterine cavity)
Longitudinal cervical axis
(in cervical canal )
Myometrium
Visceral
peritoneum
Fundus of
uterus
Rectouterine pouch
A
Body of
uterus
S
Vesicouterine
pouch
Posterior
vaginal fornix
Uterine isthmus
Supravaginal part
Vaginal part
256
Uterine cervix
Anterior vaginal
fornix
Longitudinal
vaginal axis
Longitudinal
body axis
Left uterine tube
Ampulla
Isthmus
Fundus
of uterus
Lig. of
ovary
Mesosalpinx (with
tubal brs. of
uterine a. and v.)
Infundibulum,
uterine tube
Left ovary
21 Internal Organs
Fig. 21.17 Uterus and uterine tube
Fimbriae at
abdominal ostium
Ovarian a. and v.
(in suspensory
lig. of ovary)
Vesicular
appendices
Epoöphoron
Body of
uterus
Embryonic
remnants
Mesometrium
Right ureter
Cervix of
uterus
Uterosacral lig.
(in rectouterine fold)
Vagina
A
Posterosuperior view.
Left uterine tube
Isthmus
Ampulla
Uterine
part
Uterine
ostium
Fundus of
uterus
Cavity
of uterus
Lig. of
ovary
Mesosalpinx
Infundibulum
Mesovarium
Fimbriae at
abdominal ostium
Uterine
pole
Endometrium
Vascular pole
Right ovary
Myometrium
Cervix
of uterus
Internal os
(at uterine isthmus)
Supravaginal
part
Cervical canal
Vaginal part
Vaginal fornix, lateral part
External os
B
Coronal section, posterior view with
uterus straightened. Removed: Mesometrium.
Vagina, anterior wall
Clinical box 21.2
Ectopic pregnancy
After fertilization in the ampulla of the uterine tube, the ovum usually
implants in the wall of the uterine cavity. However, it may become implanted
at other sites (e.g., the uterine tube or even the peritoneal cavity). Tubal
pregnancies, the most common type of ectopic pregnancy, pose the risk
of tubal wall rupture and potentially life-threatening bleeding into the
peritoneal cavity. Tubal pregnancies are promoted by adhesion of the tubal
mucosa, mostly due to inflammation.
257
Pelvis & Perineum
Ligaments & Fascia of the Deep Pelvis
Fig. 21.18 Ligaments of the
female pelvis
Superior view. Removed: Peritoneum, neurovasculature, and
superior portion of the bladder to
demonstrate only the fascial condensations (ligaments). Deep pelvic
ligaments support the uterus within
the pelvic cavity and prevent uterine
prolapse, the downward displacement of the uterus into the vagina.
Ilium
Sacrum
Uterosacral lig.
Rectum
Rectouterine lig.
Cardinal (transverse
cervical) lig.
Uterus
Round lig.
of uterus
Uterine
tube
Vesicouterine lig.
Lig. of ovary
Urinary
bladder
Pubovesical lig.
Pubic
symphysis
Pubis
Fig. 21.19 Ligaments of the
deep pelvis in the female
Superior view. Removed: peritoneum, neurovasculature, uterus
and bladder. Uterosacral ligaments
and the paracolpium support and
help maintain the positions of the
cervix and vagina in the pelvis.
Piriformis
Uterosacral lig.
Rectum
Cardinal (transverse
cervical) lig.
Fascia over
obturator internus
Cervix
Tendinous arch
of levator ani
Paracolpium
Tendinous arch
of pelvic fascia
Fascia over
anterior vagina
Levator ani
Lateral lig. of
the bladder
Pubovesical lig.
Obturator canal
Urethra
Pubic symphysis
258
Fig. 21.20 Fascia and ligaments of
the female pelvis
21 Internal Organs
are extensions of the tendinous arches that support the bladder
and prostate. Endopelvic fascia, a loose areolar (fatty) tissue that fills
the spaces between pelvic viscera, condenses to form “ligaments”
(cardinal, lateral visceral, and lateral rectal ligaments; see Fig. 21.20)
that provide passage for the ureters and neurovascular elements within
the pelvis.
Fascia of the pelvis plays an important role in the support of pelvic
viscera. On either side of the pelvic floor, where the visceral fascia of
the pelvic organs is continuous with the parietal fascia of the muscular
walls, thickenings called tendinous arches of the pelvic fascia are
formed. In females, the paracolpium—lateral connections between the
visceral fascia and the tendinous arches—suspends and supports the
vagina. Pubovesical ligaments (and puboprostatic ligaments in the male)
Transverse section, through cervix,
superior view.
Pubovesical
lig.
Retropubic
Vesicovaginal
space
Tendinous arch
of pelvic fascia
space
Medial
umbilical lig.
Urinary
bladder
Inferior
epigastric
a. and v.
Cervix
Superior vesical a. in
lateral vesicular lig.
Ureter
Inferior
vesical a.
Rectovaginal
space
Tendinous arch
of levator ani
Neurovascular
bundle of the
rectum (with the
middle rectal a.)
Cardinal
(transverse
cervical) lig.
Uterosacral lig.
Ovarian a.
and v.
Obturator a.
Uterine a.
Internal iliac
a. and v.
Mesorectal
space
Psoas major
muscle
Presacral Retrorectal
space
space
Rectum
Retroperitoneal
space
Parietal pelvic
fascia
Visceral
pelvic fascia
259
Pelvis & Perineum
Vagina
Fig. 21.21 Location of vagina
Vesicouterine
pouch
Midsagittal section, left lateral view.
Visceral peritoneum
on uterus
Rectouterine
pouch
Body of
uterus
Cervix of uterus,
supravaginal part
Cervix of uterus,
vaginal part
Posterior part
Urinary bladder
Anterior part
Vaginal
fornix
Vagina, posterior wall
Vagina,
anterior wall
Rectum
Urethra
Rectovaginal septum
Vesicovaginal septum
(clinical term)
Deep transverse
perineal
Vaginal orifice
External
urethral orifice
Urethrovaginal
sphincter
Vaginal vestibule
with labium minus
Fig 21.22 Relationship of the vagina to the peritoneum
and pelvic organs
Midsagittal section, left lateral view. The vagina lies almost completely
in the subperitoneal space. However, drainage of peritoneal fluid or pus
from an abcess in the rectouterine space, a procedure known as culdocentecis, can be achieved through an incision in the posterior fornix.
Fig. 21.23 Structure of vagina
Posteriorly angled coronal section, posterior view.
Posterior lip
of uterine os
Anterior lip
of uterine os
Pelvic peritoneal
cavity
Uterine
fundus
Uterine
body
Rectum
Parietal
peritoneum
Peritoneum on anterior
wall of rectum
Visceral
peritoneum on
the uterus
Uterine cervix
Anterior
vaginal
column
Vagina
260
Bladder
Vesicouterine
pouch
Vaginal rugae
Urethral carina
Vaginal
orifice
External
urethral orifice
Symphysis
Uterine os
Vagina,
anterior
wall
Rectouterine
pouch
Visceral
peritoneum on
the bladder
Cervix of uterus,
supravaginal part
Clitoris
Labium minor
Vaginal vestibule
Fig. 21.24 Female genital organs: Coronal section
Anterior view. The vagina is both pelvic and perineal in location.
It is also retroperitoneal.
Internal iliac
a. and v.
Fundus of
the uterus
Rectum
Sigmoid
colon
21 Internal Organs
Suspensory
lig. of ovary
Parietal
peritoneum
Ilium
Right external
iliac a. and v.
Iliacus
Left ovary
Cardinal (transverse
cervical) lig.
(with sections of
the uterine a. and
uterine venous plexus)
Left uterine
tube
Round lig.
of uterus
Pelvic retroperitoneal space
Cervix with
uterine os
Vaginal arterial
branches and
venous plexus
Obturator internus
(with obturator fascia)
Levator ani
(with superior and inferior
fascia of pelvic diaphragm)
Vagina, posterior
wall with vaginal
rugae
Deep transverse perineal
Ischiopubic ramus
Perineal membrane
Crus of clitoris with
ischiocavernosus
Superficial
perineal (Colles’) fascia
Urethovaginal sphincter
Perineal a.
Labium majus
Fig. 21.25 Vagina: Location
in the perineum
Transverse
perineal lig.
Inferior view.
Labium minus
Round lig.
of uterus
Vestibule of vagina
(with vaginal orifice)
Pubic
symphysis
A. of
vestibular bulb
Vestibular bulb with
bulbospongiosus
Deep dorsal
clitoral v.
Dorsal clitoral
a. and n.
Female
urethra
Inferior
pubic ramus
Perineal membrane
Vagina
Ischiocavernosus
261
Pelvis & Perineum
Female External Genitalia
Fig. 21.26 Female external genitalia
Lithotomy position with labia minora separated.
Anterior labial
commissure
Mons pubis
Prepuce of clitoris
Clitoris, glans
Frenulum of clitoris
External
urethral
orifice
Labia minora
Labia majora
Vaginal orifice
Opening of
greater vestibular
(Bartholin’s)
glands
Posterior
labial
commissure
Perineal
raphe
Fig. 21.27 Vestibule and vestibular glands
Lithotomy position with labia minora separated.
Anus
External
urethral orifice
Labia minora
Bulbospongiosus
Vaginal orifice
Vestibule of
vagina (space
between
labia minora)
Bulb of vestibule
Greater vestibular
(Bartholin’s) gland
Fig. 21.28 Erectile tissue
in the female perineum
Pubic tubercle
Pars intermedia
Body of clitoris
(corpora cavernosa)
Crus of clitoris
Glans clitoris
Urethral orifice
Corpus cavernosum
Pubic ramus
Vaginal orifice
262
Symphysis
Bulb of vestibule
Greater vestibular gland
Fig. 21.29 Erectile tissue and muscles of the female
Lithotomy position. Removed: Labia and skin. Removed from left side:
Ischiocavernosus and bulbospongiosus muscles.
Body of
clitoris
Glans of
clitoris
Crus of
clitoris
21 Internal Organs
Prepuce of
clitoris
Perineal
membrane
Ischiocavernosus
Ischial
tuberosity
Superficial
transverse
perineal
Levator ani
Bulbospongiosus
Greater vestibular gland
Bulb of
vestibule
Ischiocavernosus
Clinical box 21.3
Episiotomy
Episiotomy is a common obstetric procedure used to enlarge the birth
canal during the expulsive stage of labor. The procedure is generally used to
expedite the delivery of a baby at risk for hypoxia during the expulsive stage.
Alternately, if the perineal skin turns white (indicating diminished blood flow),
there is imminent danger of perineal laceration, and an episiotomy is often
performed. More lateral incisions gain more room, but they are more difficult
to repair.
Bulbospongiosus
Midline
episiotomy
Lateral
episiotomy
Perineum
Ischiocavernosus
Anus
Mediolateral
episiotomy
Superficial
transverse
perineal
A
Types of episiotomy.
Posterior
commissure
Levator ani
External anal
sphincter
B
Mediolateral episiotomy at height of contraction.
C
Pelvic floor with crowning of fetal head.
263
Pelvis & Perineum
Penis, Testis & Epididymis
Fig. 21.30 Penis
Corona
of glans
Glans of
penis
Corpus
cavernosum
Corpus
spongiosum
Plane of
section in D
Superior
pubic ramus
Body
of penis
Crus of penis
Obturator foramen
Bulbospongiosus
Ischiocavernosus
Plane of
section
in C
Ischiopubic ramus
Root
of penis
Bulb of penis
A
Inferior view.
Deep transverse
perineal
Perineal membrane
Urinary
bladder
Urethra,
prostatic part
Prostatic ductules
Seminal colliculus
Urethra,
preprostatic
part
Prostate
Bulbourethral
gland
Corpus
spongiosum
Pubic
symphysis
Dorsal penile
a. and n.
Urethra,
membranous
part
Deep
dorsal
penile v.
Urethral
ampulla
Crus of penis
Deep
penile a.
Corpus
cavernosum
Urethra,
spongy part
Urethra,
spongy
part
Orifices of
urethral glands
Corpus
cavernosum
Brs. of deep
penile a.
Glans of penis
264
Bulbospongiosus
C
Cross section through the root of the penis.
Navicular
fossa
External
urethral orifice,
urethral crest
Longitudinal section.
B
Bulb of penis,
corpus spongiosum
Urethral a.
Superficial dorsal
penile v.
Penile skin
21 Internal Organs
Superficial
penile fascia
Dorsal
penile
a. and n.
Deep
penile fascia
Deep
dorsal
penile v.
Tunica albuginea
of corpus
cavernosum
Deep penile a.
Penile septum
Corpus
cavernosum
Tunica albuginea
of corpus
spongiosum
Urethra,
spongy part
DCross section through
the body of the penis.
Urethral a.
Corpus
spongiosum
Fig. 21.31 Testis and epididymis
Superficial fascia, deep layer
Left lateral view.
External spermatic fascia
Internal spermatic
fascia
Cremaster m. and
cremasteric fascia
Testicular a.
Pampiniform plexus
(testicular vv.)
Tunica dartos
Tunica vaginalis,
parietal layer
Epididymis, body
Epididymis,
head
Tunica vaginalis,
visceral layer (on testis)
Glans of penis
Scrotum
A
Testis and epididymis in situ.
Epididymis,
head
Epididymis,
appendix
Testis,
appendix
Epididymis,
head
Epididymis,
body
Efferent
ductules
Testicular a.
Pampiniform
plexus (testicular vv.)
Tunica
albuginea
Epididymis,
body
Septum
Rete testis in
mediastinum
testis
Ductus
deferens
Ductus deferens
Epididymis,
tail
Epididymis,
tail
Lobule
B
Surface anatomy of the testis and epididymis.
CSagittal section of the testis and epididymis.
265
Pelvis & Perineum
Male Accessory Sex Glands
The accessory male sex glands consist of the seminal, prostate, and
bulbourethral glands, which contribute fluid to the ejaculate that
­provides nourishment for the spermatozoa as well as neutralizes the pH
of the male urethra and the vaginal environment.
Fig. 21.32 Accessory sex glands
Fig. 21.33 Anatomic divisions of
the prostate
Posterior view.
The ducts of the seminal gland and ductus deferens
combine to form the ejaculatory duct.
Neck of bladder
Prostate
Urinary
bladder
Prostatic part
Seminal colliculus
Prostatic capsule
Membranous
part
Bulbourethral gland
Ureter
Urethra
Deep transverse
perineal
Spongy part
Ductus
deferens,
ampulla
A Coronal section, anterior view.
Seminal
gland
Base
Prostatic
capsule
Prostate
Urethra
Prostatic
isthmus
Bulbourethral
glands
Left
lobe
Urethra
Ejaculatory
duct orifices
Apex
B
Sagittal section, left
lateral view.
Fig. 21.34 Clinical divisions of the
prostate
Seminal
glands
Right
lobe
C Transverse section, superior view.
Ductus
deferens
Neck of bladder
Ejaculatory
duct
Seminal
colliculus
Bladder
neck
Urethra
A Prostate and seminal glands.
Anterior zone
Peripheral zone
Periurethral zone
266
Urethra
B
Coronal section,
anterior view.
Plane of
section
in D
Prostatic
urethra
Central zone
Transition zone
Bulbourethral
gland
C
Sagittal section,
left lateral view.
Deep transverse
perineal
DTransverse section,
superior view.
Ejaculatory
ducts
Fig. 21.35 Prostate in situ
Sagittal section through the male pelvis, left lateral view.
Visceral
peritoneum
Urinary
bladder, body
Urinary
bladder, neck
Rectovesical
pouch
Superficial abdominal
fascia, deep layer
Urinary bladder, fundus
Pubic symphysis
Retropubic space
21 Internal Organs
Urinary
bladder, apex
Seminal gland
Superficial dorsal
penile v.
Rectum
Superficial and
deep penile fascia
Ejaculatory duct
Prostate
Penis, corpus cavernosum
Urethra, spongy part
Rectoprostatic fascia
Deep transverse
perineal
Penis, corpus spongiosum
Bulbourethral gland
Glans of penis
Bulbospongiosus
Prepuce
Urethra,
navicular fossa
Scrotal septum
Scrotum
Clinical box 21.4
Prostatic carcinoma and hypertrophy
Prostatic carcinoma is one of the most common malignant tumors in older
men, often growing at a subcapsular location (deep to the prostatic capsule)
in the peripheral zone of the prostate. Unlike benign prostatic hyperplasia,
which begins in the central part of the gland, prostatic carcinoma does not
cause urinary outflow obstruction in its early stages. Being in the peripheral
Urinary
bladder
zone, the tumor is palpable as a firm mass through the anterior wall of the
rectum during rectal examination. In certain prostate diseases, especially
cancer, increased amounts of a protein, prostate-specific antigen or PSA,
appear in the blood. This protein can be measured by a simple blood test.
Rectovesical
pouch
Rectum
Prostatic
carcinoma,
subcapsular
A
Most common site of prostatic carcinoma.
B
Prostatic carcinoma
(arrows) with bladder
infiltration.
267
22
Neurovasculature
Pelvis & Perineum
Overview of the Blood Supply to Pelvic Organs & Wall
Fig 22.1 Branches of the
right internal iliac artery
Side wall of the male pelvis, left
lateral view. The internal iliac
artery arises from the common
iliac artery. Its anterior trunk gives
off visceral branches to pelvic
organs and parietal branches to
the pelvic wall. The posterior
trunk gives off only parietal
branches. Branches to the uterus
and vagina in the female are the
principal differences from the
male vasculature.
Abdominal aorta
L 5 vertebra
Right common
iliac a.
Median sacral a.
Right internal
iliac a.
Iliolumbar a.
Right external
iliac a.
Internal iliac a.,
posterior trunk
Umbilical a.,
patent part
Lateral sacral a.
Superior gluteal a.
Internal iliac a.,
anterior trunk
Inferior gluteal a.
Sacral plexus
Obturator n.
Inferior vesical a.
Obturator a.
Middle rectal a.
Umbilical a.,
occluded part
Coccygeus
Inferior epigastric a.
Obturator
internus
Superior vesical a.
Internal
pudendal a.
Obturator br. of
inferior epigastric a.
Pudendal n.
A. of ductus deferens
Table 22.1
Neurovascular pathways in the pelvis
There are six major neurovascular tracts on the pelvic walls, four of
which (*) contain branches from the internal iliac artery.
Tract
Posterior
① Greater sciatic foramen, suprapiriform
part* (above the piriformis)
reater sciatic foramen, infrapiriform
② G
part* (below the piriformis)
On pelvic floor
③ Lesser sciatic foramen through
pudendal canal*
Superior gluteal a. and v.,
superior gluteal n.
Inferior gluteal a. and v., inferior
gluteal n., sciatic n., internal
pudendal a. and v., pudendal n.,
posterior femoral cutaneous n.
Internal pudendal a. and v.,
pudendal n.
Lateral
④ Obturator canal*
Obturator a. and v., obturator n.
Anterior
⑤ Muscular lacuna (posterior to inguinal
lig., lateral to iliopectineal arch)
Femoral n., lateral femoral
cutaneous n.
⑥ V
ascular lacuna (posterior to inguinal
lig., medial to iliopectineal arch)
268
Neurovascular structures
transmitted
Femoral a. and v., lymphatic
vessels (the femoral a. is a
branch of the external iliac a.),
femoral branch of genitofemoral n.
①
⑤
Piriformis
②
Inguinal
lig.
⑥
Iliopectineal
arch
④
Obturator
membrane
Sacrospinous
lig.
Sacrotuberous
lig.
③
External
iliac a.
Internal
iliac a.
Right common iliac v.
Inferior vena cava
Right internal iliac v.
②
①
③
④
A. of
ductus
deferens
Superior
vesical a.
③
⑨
⑥
Right external
iliac v.
④
Dorsal
penile a.
⑨
⑧
⑥
⑦
Deep dorsal
penile v.
Inferior rectal a.
Posterior
scrotal brs.
A
Male pelvis.
⑧
⑤
⑦
⑤
②
Vv. of
penile bulb
Deep penile vv.
Inferior
rectal vv.
Posterior
scrotal vv.
A
Male pelvis.
Abdominal
aorta
Left common
iliac a.
Left external
iliac a.
Left internal
iliac a.
Right internal
iliac a.
Inferior
vena cava
Right
internal
iliac v.
②
Left
ureter
Piriformis
⑨
⑤
Coccygeus
④
①
Uterine
vv.
⑥
Inferior rectal a.
B
Female pelvis.
Table 22.2
②
Uterine a.
Vaginal a.
⑧
⑦
⑦
⑧
③
Right
external
iliac v.
④
⑤
⑥
⑩
Branches of the internal iliac artery
The internal iliac artery gives off five parietal (pelvic wall) and four visceral
(pelvic organs) branches.* Parietal branches are shown in italics.
Branches
①
liolumbar a.
②
Superior gluteal a.
③
Lateral sacral a.
④
Umbilical a.
⑤
B
Female pelvis.
Table 22.3
Venous drainage of the pelvis
Tributaries
①
Superior gluteal v.
②
Lateral sacral v.
③
Obturator vv.
Obturator a.
④
Vesical vv.
⑥
Inferior vesical a.
⑤
Vesical venous plexus
⑦
Middle rectal a.
⑥
Middle rectal vv. (rectal venous plexus) (also superior and inferior
rectal vv., not shown)
⑧
Internal pudendal a.
⑦
Internal pudendal v.
⑧
Inferior gluteal vv.
⑨
Prostatic venous plexus
⑩
Uterine and vaginal venous plexus
A. of ductus deferens
Superior vesical a.
Inferior rectal a.
Dorsal penile a.
Posterior scrotal aa.
⑨
22 Neurovasculature
①
Inferior gluteal a.
* In the female pelvis, the origin of the uterine and vaginal arteries is highly
variable.
The male pelvis also contains veins draining the penis and scrotum.
269
Pelvis & Perineum
Arteries & Veins of the Male Pelvis
Fig 22.2 Blood vessels of the male pelvis
Right hemipelvis, left lateral view.
Abdominal aorta
Inferior mesenteric a.
Left common
iliac a. and v.
Median sacral a.
Right internal iliac a. and v.
Umbilical a.
Right iliolumbar a.
Right ureter
Right lateral sacral v.
Right external
iliac a. and v.
Right inferior gluteal a. and v.
Superior rectal a.
and v. (from/to inferior
mesenteric a. and v.)
Right obturator
a. and v.
Internal pudendal
a. and v.
Right superior
vesical a. and v.
Right inferior vesical
a. and v.
Right ductus
deferens and a.
Right middle rectal
a. and v.
Left ureter
Seminal gland
Left superior and
inferior vesical
a. and v.
Left middle rectal
a. and v.
Dorsal penile a.,
deep dorsal penile v.
Prostate
Left inferior rectal
a. and v.
Spermatic cord
Left internal pudendal
a. and v.
Perineal a. and v.
Posterior scrotal a. and v.
270
Fig 22.3 Blood vessels of the male genitalia
Opened: Inguinal canal and coverings of the spermatic cord
Iliacus
Psoas major
Right ureter
Testicular a. and v.
Internal iliac
a. and v.
External iliac
a. and v.
Sacral plexus
Umbilical a.
Inguinal lig.
Inferior epigastric
a. and v.
Rectum
Saphenous opening
Urinary
bladder
External pudendal
a. and v.
Femoral a. and v.
Suspensory
lig. of penis
Pampiniform plexus
(testicular vv.)
Left ductus
deferens
Dorsum of penis
Right ductus
deferens
Dorsal penile a.,
deep dorsal penile v.
Internal
spermatic fascia
Testis
Epididymis
Glans of penis
Clinical box 22.1
Fig 22.4 Blood vessels of the testis
Left lateral view.
Pampiniform
plexus
(testicular vv.)
22 Neurovasculature
Deep circumflex
iliac a. and v.
Asymmetric venous drainage of the testes
Testicular a.
The pampiniform plexus has an important cooling affect on the testis.
Because drainage of the left testicular vein into the left renal vein is at
a right angle, a physiological constriction may occur that can obstruct
outflow from the testicular vein. This can result in enlargements, or
“varicoceles,” of the left testicular vein and pampiniform plexus, which
can disrupt the cooling function of the plexus and the fertility of the testis.
A. of
ductus deferens
Left renal v.
Vv. of ductus
deferens
Cremasteric a. and v.
Inferior
vena cava
Left testicular v.
Inguinal canal
Testicular vv.
(pampiniform
plexus)
271
Pelvis & Perineum
Arteries & Veins of the Female Pelvis
Fig 22.5 Blood vessels of the female pelvis
Right hemipelvis, left lateral view.
Right common
iliac a.
Right ovarian a. and v.
(in ovarian suspensory lig.)
Right umbilical a.
Right ureter
Right superior
vesical a.
Right ovary and
uterine tube
Right internal
iliac a.
Median sacral a.
Right iliolumbar a.
Internal iliac a. and v.,
anterior division
Right uterine a. and v.
Right inferior
vesical a., vesical v.
Superior rectal
a. and v.
Right vaginal a.
Right obturator
a. and v.
Right external iliac
a. and v.
Right round
lig. of uterus
Left superior
vesical a., vesical v.
Left ureter
Deep dorsal
clitoral v.
Right middle rectal
a. and v.
Uterine venous
plexus
Left uterine
a. and v.
Vaginal venous
plexus
Left middle rectal
a. and v.
Left inferior vesical
a., vesical v.
Left inferior rectal
a. and v.
Left internal pudendal
a. and v.
Perineal a. and v.
272
Fig 22.6 Blood vessels
of the female genitalia
Left ureter
Left ovarian a. and v.
Abdominal
aorta
Inferior mesenteric a.
Inferior vena cava
Left common
iliac a. and v.
Median sacral
a. and v.
Left internal
iliac a. and v.
Left external
iliac a. and v.
Rectum
Uterine a.,
tubal br.
Uterine tube
22 Neurovasculature
Removed: peritoneum on left
side; Retracted: uterus.
Ovary
Fundus of uterus
Umbilical a.,
patent part
Middle rectal a.
Obturator a., v.,
and n.
Uterine a. and v.
Round lig.
of uterus
Inferior
vesical a.
Vaginal a.
Superior vesical
a., vesical v.
Mesometrium
(of broad lig.
of uterus)
Umbilical a.,
obliterated part
Urinary bladder
Visceral peritoneum
on urinary bladder
Urinary bladder
Uterus, fundus
Visceral peritonium
on posterior surface
of uterus
Obturator a.
Round lig.
of uterus
Superior vesical a.
Fig 22.7 Relationship of
the uterine artery and
ureter
The uterine artery runs in the
broad ligament to the uterus.
The ureter passes inferior to the
artery lateral to the cervix. Thus
the ureter is at risk for injury
during uterine surgery.
Broad lig.
External iliac
a. and v.
Uterine tube
Ovary
Uterine a.
Inferior vescial a.
Left ureter
Right ureter
Internal iliac
a. and v.
Rectouterine
fold
Rectum
Common
iliac a.
Uterus
Rectum
Left
ureter
A
Superior view of the pelvis.
Bladder
B Left lateral view of left ureter
and left uterine artery.
Left
uterine a.
Vaginal br.
273
Pelvis & Perineum
Arteries & Veins of the Rectum & External Genitalia
Fig. 22.8 Blood vessels of the rectum
Posterior view. The superior rectal arteries are the main blood supply to
the rectum; the middle rectal arteries serve as an anastomosis between
the superior and inferior rectal arteries. Similarly, the middle rectal
To portal v.
Inferior
mesenteric
a. and v.
veins provide an important portocaval collateral pathway between the
superior and inferior rectal veins.
Abdominal
aorta
Inferior
vena cava
Median sacral
a. and v.
Right common
iliac a. and v.
Sigmoid
aa. and vv.
Superior rectal
a. and v.
Right superior
gluteal a. and v.
Left external
iliac a. and v.
Right internal iliac a. and v.
Left obturator a.
Right obturator v.
Left inferior
gluteal a.
Right inferior
gluteal v.
Left middle
rectal a.
Right middle
rectal v.
Left internal
pudendal a.
Left inferior
rectal a.
Rectal
venous
plexus
Levator ani
Right inferior
rectal v.
Right internal
pudendal v.
Fig. 22.9 The hemorrhoidal plexus
Longitudinal section of the anal canal with the
hemorrhoidal plexus windowed.
The hemorrhoidal plexus, supplied by branches
of the superior rectal artery, is a permanently
distended cavernous body that forms circular
cushions in the area of the anal columns. When
filled with blood, these cushions serve as an
effective continence mechanism that ensures
liquid and gas-tight closure. The sustained
contraction of the muscular sphincter apparatus inhibits venous drainage, but when the
sphincter relaxes during defecation, blood is
allowed to drain via arteriovenous anatomoses
to the inferior mesenteric vein and middle and
inferior rectal veins.
274
Muscularis mucosae
of the anal canal
Hemorrhoidal
plexus
Superior
rectal a. and v.
Puborectalis
Transsphincteric vv.
Pectinate
line
External anal
sphincter
Anal pecten
Rectal vv. of external
venous plexus
Proctodeal gland
Femoral
a. and v.
External pudendal
a. and v.
22 Neurovasculature
Fig. 22.10 Neurovasculature of the penis and scrotum
Superficial
inguinal ring
Ilioinguinal n.
External
spermatic fascia
External
pudendal a. and v.
Deep dorsal
penile v.
Suspensory
lig. of penis
Dorsal penile
a. and n.
Anterior scrotal
a. and v.
Deep penile fascia
Tunica
albuginea
Superficial dorsal
penile vv.
Superficial dorsal
penile vv.
Deep dorsal
penile v.
Deep penile
fascia
Dorsal penile
a. and n.
Corona of
glans
Superficial
penile fascia
Glans, penis
B
Dorsal vasculature of the penis.
Removed from left side: Deep penile fascia.
A
Anterior view. Partially removed: Skin and fascia.
Fig. 22.11 Blood vessels of the female external genitalia
Inferior view.
Dorsal
clitoral a.
Deep
clitoral a.
A. of
vestibular
bulb
Posterior
labial brs.
Crus of
clitoris
Vestibular
bulb
Superficial
transverse
perineal
Perineal a.
Internal
pudendal a.
A
Arterial supply.
Inferior
rectal a.
Deep dorsal
clitoral v.
Deep
clitoral vv.
Venous plexus
of vestibular
bulb
V. of
vestibular
bulb
Posterior
labial vv.
Perineal vv.
Internal
pudendal v.
Inferior
rectal vv.
B
Venous drainage.
275
Pelvis & Perineum
Lymphatics of the Pelvis
Table 22.4
Lymph nodes of the pelvis are distributed along major blood vessels and
anterior to the sacrum. Lymph from pelvic organs can drain to one or more of
several groups of lymph nodes (inguinal, internal iliac, external iliac, sacral or
common iliac) before passing to the preaortic or lateral aortic nodes. Lymph
from the perineum may drain first to superficial or deep inguinal nodes before
draining to the external iliac nodes. Note that the testes and ovaries drain
directly to lateral aortic nodes.
①
④
Lymph nodes of the pelvis
③
②
⑤
Preaortic l.n.
① Superior mesenteric l.n.
② Inferior mesenteric l.n.
③ Left lateral aortic l.n.
④ Right lateral aortic (caval) l.n.
⑩
⑥
⑦
⑤ Common iliac l.n.
⑥ Internal iliac l.n.
Horizontal
group
Vertical
group
⑨
⑦ External iliac l.n.
⑧
⑧ Superficial inguinal l.n.
Horizontal group
Vertical group
⑨ Deep inguinal l.n.
⑩ Sacral l.n.
Fig 22.12 Lymphatic drainage of the rectum
Anterior view. Three zones of the rectum drain to different
groups of lymph nodes. The upper zone drains to inferior
mesenteric nodes. The middle zone and columnar part of
the lower zone drains to internal iliac nodes. The cutaneous
part of the lower zone drains to superficial inguinal nodes.
Abdominal aorta
Fig 22.13 Lymphatic drainage of the bladder
and urethra
Anterior view. Different parts of the bladder drain to internal iliac or ­external iliac nodes or directly to the common
iliac nodes. The urethra, as well as the penis in the male, is
drained by superficial and deep inguinal nodes.
Inferior mesenteric a.
and l.n.
Superior rectal a.
Common iliac a.
Internal iliac a.
and l.n.
Superficial
inguinal l.n.
276
Common
iliac l.n.
Internal
iliac l.n.
Superficial and
deep inguinal l.n.
External
iliac l.n.
Fig 22.14 Lymphatic drainage of the male genitalia
Prostate – drain along multiple pathways including to external iliac,
internal iliac, and sacral nodes
Testis and epididymis – drain via a direct pathway along the testicular
vessels to the right and left lumbar lymph nodes. Some lymph from the
epididymis may drain first to internal iliac nodes.
Scrotum and coverings of the testes – drain to superficial inguinal
nodes
Ductus deferens and seminal glands – drain to external iliac
­(primarily) and internal iliac nodes.
Abdominal
aorta
Lateral aortic l.n.
Lumbar l.n.
22 Neurovasculature
Male pelvis, anterior view. Male genitalia drain to the lumbar lymph
nodes via several pathways:
Testicular a.
Internal iliac l.n.
Sacral l.n.
External iliac l.n.
A
Lymphatic drainage of the prostate, epididymis,
ductus deferens and testes.
Lymphatic drainage
from the testis
and epididymis
Superficial
inguinal l.n.
Lymphatic drainage
from the scrotum
and coverings
of the testis
Femoral a.
B
Lymphatic drainage of the testes and scrotum.
Fig 22.15 Lymphatic drainage of the female genitalia
Female pelvis, anterior view. Female genitalia drain to the lumbar
lymph nodes via several pathways:
Uterine cervix, middle and upper part of vagina – drain to deep
inguinal nodes
Ovary, uterine fundus and distal part of uterine tube – drain via a
direct pathway along the ovarian vessels to right and left lumbar lymph
nodes.
External genitalia (except anterior clitoris) – drain to superficial
i­ nguinal nodes
Uterine fundus and body, and proximal part of uterine tube – drain
to internal iliac, external iliac, and sacral nodes.
Body and glans of the clitoris – drain to deep inguinal and internal
iliac nodes
Lymphatic drainage of
the anterior clitoris
Inferior vena cava
Right lateral aortic
(caval) l.n.
Right
common
iliac a.
Abdominal aorta
Internal iliac
lymph nodes
Left lateral aortic l.n.
Common
iliac l.n.
Internal
iliac l.n.
Sacral l.n.
Superficial
inguinal l.n.
(horizontal
group)
External
iliac l.n.
Deep
inguinal l.n.
Superficial
inguinal l.n.
Deep
inguinal l.n.
Superficial inguinal l.n.
(vertical group)
A
Lymphatic drainage of the ovary, uterus, uterine tube, vagina, and
labia.
B
Lymphatic drainage of the clitoris.
277
Pelvis & Perineum
Lymph Nodes of the Genitalia
Fig. 22.16 Lymph nodes of the male genitalia
Anterior view. Removed: Gastrointestinal tract (except rectal
stump) and peritoneum.
Left lumbar l.n.
Right lumbar l.n.
Inferior mesenteric l.n.
Intermediate
lumbar l.n.
Common iliac l.n.
Abdominal
aorta
Promontory l.n.
Sacral l.n.
External iliac l.n.
External
iliac a.
Rectum
Urinary bladder
Superficial inguinal
l.n., horizontal group
Deep inguinal l.n.
Superficial inguinal
l.n., vertical group
Epididymis
Testis
Penis
Scrotum
278
Fig. 22.17 Lymph nodes of the female genitalia
Anterior view. Removed: Gastrointestinal tract (except rectal stump) and
peritoneum. Retracted: Uterus.
Inferior mesenteric l.n.
Common iliac l.n.
Promontory l.n.
Rectum
Sacral l.n.
Uterine tube
22 Neurovasculature
Intermediate
lumbar l.n.
Internal iliac l.n.
Ovary
External iliac l.n.
Uterus
Obturator l.n.
Mesometrium
Superficial inguinal
l.n., horizontal group
Intermediate
lacunar l.n.
Urinary bladder
Superficial inguinal
l.n., vertical group
Deep inguinal l.n.
Fig. 22.18 Lymphatic drainage of the pelvic organs
Thoracic duct
Right lumbar trunk
Cisterna chyli
Left lumbar trunk
Right lumbar l.n.
Left lumbar l.n.
Lateral caval l.n.
Lateral aortic l.n.
Intermediate lumbar l.n.
Precaval l.n.
Preaortic l.n.
Retrocaval l.n.
Lacunar l.n. (lateral,
medial, and intermediate)
Deep inguinal l.n.
Retroaortic l.n.
External iliac l.n.
Common iliac l.n.
Internal iliac l.n.
Obturator l.n.
Subaortic l.n.
Sacral l.n.
Lateral, medial, and
intermediate external
iliac l.n.
Promontory l.n.
Superior and inferior
gluteal l.n.
Interiliac l.n.
Lateral, medial, and
intermediate common
iliac l.n.
Visceral pelvic l.n.
Superficial inguinal l.n.
Pararectal l.n.
Parauterine l.n.
Paravaginal l.n.
Lateral vesical l.n.
Pre- and retrovesical l.n.
279
Pelvis & Perineum
Autonomic Innervation of the Genital Organs
Fig 22.19 Innervation of the male pelvis
Intermesenteric plexus
Inferior mesenteric plexus
Sympathetic trunk,
lumbar ganglia
Lumbar
splanchnic nn.
Gray ramus
communicans
Ureteral plexus
Lumbar nn.,
anterior rami
L5 vertebra
Superior hypogastric plexus
Lumbosacral
trunk
Right hypogastric n.
Left hypogastric n.
Iliac plexus
Pelvic splanchnic nn.
Obturator n.
Middle
rectal plexus
Pudendal n.
Deferential
plexus
Seminal gland
Inferior rectal
plexus
Vesical plexus
Inferior rectal nn.
Prostatic plexus
Cavernous
nn. of penis
Sympathetic
trunk
Lesser splanchnic n.
(T10-T11)
Least splanchnic n.
(T12)
Lumbar splanchnic n.
(L1-L2)
Superior mesenteric ganglion
Renal
ganglion
Dorsal n.
of the penis
Posterior
scrotal nn.
A
Right pelvis, left lateral view.
Intermesenteric
plexus
Inferior mesenteric ganglion
Superior hypogastric
plexus
Pelvic splanchnic nn.
(S2-S4)
Inferior hypogastric
plexus **
Sacral splanchnic nn.
(S1-S4)
Parasympathetic postganglionic fibers
Seminal vesicle
Prostate with
prostatic plexus
Ductus deferens
with deferential
plexus
280
Sympathetic postganglionic fibers
Parasympathetic preganglionic fibers
Bladder with
vesical plexus
Testicular
plexus
Sympathetic preganglionic fibers
Epididymis,
testes
**Minimal sympathetic
preganglionic fibers traveling
through the sacral splanchnic
nerves will synapse in the ganglia
located in the inferior hypogastric
plexus
B
Schematic of innervation of male
genitalia.
Fig 22.20 Innervation of the female pelvis
Intermesenteric plexus
Sympathetic trunk,
lumbar ganglia
Lumbar
splanchnic nn.
Gray ramus
communicans
Ureteral plexus
Lumbar nn.,
anterior rami
L5 vertebra
Left hypogastric n.
Superior hypogastric plexus
1st sacral n.,
anterior ramus
Right hypogastric n.
22 Neurovasculature
Inferior mesenteric plexus
Lumbosacral
trunk
Ovarian plexus
Obturator n.
Sacral plexus
Right inferior
hypogastric
plexus
Pelvic splanchnic nn.
Vesical plexus
Pudendal n.
Right uterovaginal plexus
Right middle
rectal plexus
Sympathetic
trunk
A
Right pelvis, left lateral view.
Lesser splanchnic n.
(T10-T11)
Least splanchnic n.
(T12)
Celiac
ganglion
Renal
ganglion
Superior
mesenteric
ganglion
Lumbar splanchnic n.
(L1-L2)
Intermesenteric
plexus
Inferior
mesenteric
ganglion
Pelvic splanchnic nn.
(S2-S4)
Superior
hypogastric
plexus
Sacral splanchnic nn.
(S1-S4)
Hypogastric nn.
**Inferior hypogastric plexus
Uterovaginal
plexus
Ovarian
plexus
Uterus
Uterine
tube
Vagina
Sympathetic preganglionic fibers
Sympathetic postganglionic fibers
Parasympathetic preganglionic fibers
Parasympathetic postganglionic fibers
**Minimal sympathetic preganglionic
fibers traveling through the sacral
splanchnic nerves will synapse in
the ganglia located in the inferior
hypogastric plexus.
Ovary
Schematic of innervation of female
B
genitalia.
281
Pelvis & Perineum
Autonomic Innervation of the Urinary Organs & Rectum
Fig 22.21 Innervation of the pelvic urinary organs
See pp. 215 and 217 for innervation of the kidneys and upper ureters.
Intermesenteric plexus
Inferior mesenteric ganglion
Sympathetic trunk,
lumbar ganglia
Ureteral plexus
Testicular plexus
Inferior mesenteric plexus
Superior hypogastric plexus
Iliac plexus
Left hypogastric n.
Sympathetic trunk,
sacral ganglia
Right hypogastric n.
1st sacral n.,
anterior ramus
Sympathetic
trunk
Inferior hypogastric plexus
Pelvic splanchnic nn.
Middle rectal
plexus
Vesical plexus
Lumbar splanchnic n.
(L1-L2)
Sympathetic
trunk
Prostatic plexus
Inferior
mesenteric
ganglion
Sacral
Lumbar splanchnic n.
splanchnic nn.
(L1-L2)
A
Anterior view of male pelvis (S1-S4)
and
lower abdomen.
Inferior
mesenteric
ganglion
Sacral
splanchnic nn.
(S1-S4)
Sympathetic
trunk
Superior
hypogastric
plexus
Lumbar splanchnic n.
(L1-L2)
Superior
hypogastric
plexus
Sympathetic preganglionic fibers
Seminal
Pelvic splanchnic
Sympathetic postganglionic fibers
vesicle
nn. (S2-S4)
Parasympathetic preganglionic fibers
**Inferior hypoParasympathetic postganglionic fibers
gastric plexus
Ureter (abdominal
and pelvic parts)
Vesical plexus
Prostate
Sympathetic preganglionic fibers
Ureteral plexus
Sympathetic postganglionic fibers
Parasympathetic preganglionic fibers
Parasympathetic postganglionic fibers
Bladder
Vesical plexus
Sympathetic preganglionic fibers
282
Sympathetic postganglionic fibers
Parasympathetic preganglionic fibers
Parasympathetic postganglionic fibers
Prostate
**Minimal sympathetic preganglionic fibers
traveling through the sacral splanchnic nerves
will synapse in the ganglia located in the
inferior hypogastric plexus.
Ureteral plexus
Prostate
**Minimal sympathetic preganglionic
traveling through the sacral splanchn
will synapse in the ganglia located in
inferior hypogastric plexus.
**Minimal sympathetic preganglionic fibers
traveling through the sacral splanchnic nerves
will synapse in the ganglia located in the
inferior hypogastric plexus.
Seminal
vesicle
Pelvic splanchnic
nn. (S2-S4)
**Inferior hypogastric plexus
Ureter (abdominal
and pelvic parts)
Ureter (abdominal
and pelvic parts)
Pelvic splanchnic
nn. (S2-S4)
Ureteral
plexus
**Inferior hypogastric plexus
Bladder Vesical plexus
Inferior
mesenteric
ganglion
Sacral
splanchnic nn.
(S1-S4)
Superior
hypogastric
plexus
B
Schematic of the urinary bladder
and ureter.
Fig 22.22 Innervation of the anal
sphincter mechanism
22 Neurovasculature
Sympathetic
trunk
L 5 vertebra
Lumbar
splanchnic nn.
Superior hypogastric plexus
Sacral plexus
Branches
from S2– S4
L 5 vertebra
Pudendal n.
Sacral
splanchnic nn.
Rectum
Levator ani muscle
Superficial
and deep
parts
Inferior
rectal nn.
Subcutaneous
part
Cutaneous
zone
Inferior hypogastric plexus
External anal
sphincter
Internal anal
sphincter
A
Somatomotor and somatosensory innervation:
The pudendal nerves and inferior rectal branches
provide active, partly voluntary innervation of the
external anal sphincter and levator ani muscles,
and sensation for the anus and perianal skin.
Sacral
plexus
Pelvic
splanchnic nn.
Rectal plexus
Rectum
Internal anal
sphincter
Visceromotor and viscerosensory innervation: Pelvic
B
splanchnic nerves (S2-4) innervate the internal anal
sphincter, which helps to maintain closure of the
anal canal. They also supply sensation to the wall
of the rectum, particularly the stretch receptors in
the rectal ampulla, which when stretched trigger an
awareness of the need to defecate.
Clinical box 22.2
Mechanism of defecation (after Wedel)
Both defecation and continence are under central nervous system control
involving such diverse structures as the cerebral cortex, muscles of the
abdomen and pelvis and perianal skin.
Filling of the rectal ampulla and stimulation of local stretch receptors
in the ampullary wall. When the fecal bolus is propelled into the ampulla,
mechanoreceptors detect distension and transmit the information to the
sensory cortex, which perceives the urge to defecate.
Rectoanal inhibitory reflex and relaxation of the voluntary innervated
sphincters. When the ampulla fills, the intrarectal pressure increases and
the internal anal sphincter relaxes. This is followed by voluntary relaxation
of the puborectalis sling and the external anal sphincter, which results in the
straightening of the anorectal angle and widening of the anal canal.
Propulsion of the fecal column. Rectal evacuation is assisted by a direct
involuntary increase in pressure in the rectal area and by simultaneous
increase in pressure by the contraction of voluntarily innervated muscles in
the abdomen wall, pelvic floor, and diaphragm. With propulsion of the fecal
column, the hemorrhoidal cushions are drained and pushed out.
Completion of defecation. After the sphincter apparatus allows the fecal
column to pass through, it comes in contact with the highly sensitive
anoderm, which perceives the volume, consistency and location of the stool.
This perception initiates the voluntary process of completing defecation,
which is marked by the contraction of the sphincter apparatus and filling of
the hemorrhoidal plexus.
283
Neurovasculature of the Male & Female Perineum
Pelvis & Perineum
Fig. 22.23 Nerves of the male
perineum and genitalia
Scrotum
Bulbospongiosus
Lithotomy position.
Ilioinguinal n. and
genitofemoral n.,
genital br.
Posterior scrotal nn.
(brs. of pudendal n.)
Pudendal n.
Posterior femoral
cutaneous n.
Dorsal n. of penis
(br. of pudendal n.)
Superficial
transverse
perineal
Gracilis
Inferior clunial nn.
Adductor
magnus
Posterior femoral
cutaneous n.
Pudendal n.
Ilioinguinal n. and
genitofemoral n.,
genital br.
Ischial
tuberosity
Pudendal n.
Perineal nn.
(brs. of
pudendal n.)
Posterior femoral
cutaneous n.
Anococcygeal nn.
of penis
endal n.)
Middle clunial nn.
Anus
Superior clunial nn.
ioernosus
External anal
sphincter
Inferior clunial nn.
Adductor
magnus
Fig. 22.24 Neurovasculature
male perineum
Posterior femoral
of the
cutaneous n.
Lithotomy position.
from left side:
PudendalRemoved
n.
Perineal membrane,
Ischial bulbospongiosus, and
tuberosity
root of penis.
Perineal nn.
(brs. of
pudendal n.)
Corpus
spongiosum
Corpora
cavernosa
Levator
ani
Gluteus
maximus
Deep dorsal
penile v.
Arcuate
pubic lig.
Transverse
perineal lig.
Spermatic
cord
Bulbospongiosus
Dorsal penile a.
Dorsal
penile n.
Posterior
scrotal nn.
Muscular brs.
Perineal nn.
Bulbourethral
gland
Anus
Inferior
rectal nn.
External anal
sphincter
Gluteus
maximus
284
Inferior rectal nn.
(br. of pudendal n.)
Middle clunial nn.
Superior clunial nn
Ischiocavernosus
Perineal
body
Anococcygeal nn.
Ischial
tuberosity
Internal
pudendal a. and v.
Pudendal n.
Inferior rectal
a. and v.
Posterior femoral
cutaneous n.
Middle clunial nn.
clunial nn.
Fig. 22.25 Nerves ofSuperior
the female
perineum and genitalia
Inferior clunial nn.
External
urethral orifice
Glans of
clitoris
Bulbospongiosus
Dorsal clitoral n.
(br. of pudendal n.)
Posterior labial nn.
(br. of pudendal n.)
Gracilis
Labium minus
Ischiocavernosus
Vaginal orifice
Perineal membrane
Superficial
transverse
perineal
Adductor
magnus
Perineal body
22 Neurovasculature
Sensory innervation of the female
perineum. Lithotomy position.
Anococcygeal nn.
Posterior femoral
cutaneous n.,
perineal brs.
Perineal nn.
(brs. of
Ilioinguinal n. and
pudendal n.)
genitofemoral n.,
genital br. and labial br.
Posterior femoral
cutaneous n.
Ischial
tuberosity
Pudendal n.
Posterior femoral
cutaneous n.
Pudendal n.
Middle clunial nn.
Superior clunial nn.
Inferior clunial nn.
External
urethral orifice
Anus
Glans of
clitoris
Bulbospongiosus
External anal
sphincter
Anococcygeal nn.
Dorsal clitoral n.
(br. of pudendal n.)
Inferior rectal nn.
(brs. of pudendal n.)
Levator
ani
Gluteus
Inferior
Posterior labial nn.
maximus
clunial nn.
(br. of pudendal n.)
Gracilis
Labium minus
Fig. 22.26 Neurovasculature
of the female
perineum
Vaginal orifice
Lithotomy position.
Removed fromSuperficial
left side:
transverse
Bulbospongiosus
and
perineal
­ischiocavernosus.
Bulbospongiosus
Vestibular bulb
Ischiocavernosus
Crus of clitoris
Perineal membrane
Ischiocavernosus
Dorsal clitoral a. and n.
Adductor
magnus
Anterior labial nn.
Posterior femoral
cutaneous n.,
perineal brs.
Deep clitoral a.
Posterior femoral
cutaneous n.
A. of vestibular bulb
Ischial
tuberosity
Perineal body
Perineal a.
Perineal nn.
(brs. of
pudendal n.)
Superficial
transverse perineal
Pudendal n.
Posterior labial nn.
Ischial tuberosity
Inferior rectal
a. and v.
Anus
External anal
sphincter
Inferior rectal nn.
(brs. of pudendal n.)
Levator
ani
Gluteus
maximus
Inferior
clunial nn.
Pudendal n.
Internal
pudendal
a. and v.
Greater vestibular
gland
Perineal
membrane
Perineal nn.
Inferior
rectal nn.
Levator ani
285
Pelvis & Perineum
23 Sectional & Radiographic Anatomy
Sectional Anatomy of the Pelvis & Perineum
Femoral a., v., and n.
Pubis
Urinary
bladder
Fig. 23.1 Female pelvis
Pectineus
Transverse section through
the bladder and cervix of the
uterus. Inferior view.
Iliopsoas
Obturator canal
(inlet)
Head of femur
Lig. of head
of femur
Obturator
internus
Left ureter
(cut obliquely)
Cervix
of uterus
Uterovaginal
venous plexus
Sciatic n.
Ischial spine
Rectum
Gluteus
maximus
Sacrospinous
lig.
Fig. 23.2 Male pelvis
Transverse section through the bladder
and seminal glands. Inferior view.
Coccyx
Rectouterine
pouch
Rectus abdominis
Ductus
deferens
Uterosacral
lig.
Urinary
bladder
Orifice of
right ureter
Femoral a., v., and n.
Iliopsoas
Head of femur
Obturator a., v., and n.
Seminal gland
Rectovesical
septum
Rectum
Sciatic n.
Gluteus maximus
Inferior vesical a.
Vesicoprostatic
venous plexus
Inferior
hypogastric plexus
Obturator
internus
Ischial spine
Sacrospinous lig.
Coccyx
286
Transverse section through the prostate
gland and anal canal. Inferior view.
Corpora cavernosa
of penis
Femoral a.,
v. and n.
Spermatic
cord
Adductor
mm.
Inferior pubic
ramus
Prostatic
urethra
Pubic
symphysis
Levator ani
23 Sectional & Radiographic Anatomy
Fig. 23.3 Male pelvis
Obturator
externus
Prostate
Obturator
membrane
Seminal
gland
Rectoprostatic
fascia
Rectum
Ischial
tuberosity
Sciatic n.
Obturator
internus
Gluteus
maximus
Ischioanal
fossa
Pudendal n., internal
pudendal a. and v.
287
Pelvis & Perineum
Radiographic Anatomy of the Female Pelvis
Fig 23.4 MRI of the female pelvis
Symphysis
Transverse section, inferior view.
Femoral a.
Femoral v.
Uterine body
Bladder
Round lig.
Follicle
Follicle
A
B
C
Ovary
Acetabulum
Proper
ovarian lig.
Ovary
Sigmoid colon
Iliac vessels
A
Section through the body of the uterus.
(Reproduced from Krombach GA,
Mahnken AH. Body Imaging: Thorax
and Abdomen. New York, NY: Thieme;
2018.)
Sacrum
Bladder
Cervix
Head of femur
Rectouterine pouch
Obturator internus
Gluteus maximus
Rectum
Coccyx
Sartorius
Femoral a.,
v., and n.
Urethra
B
Section through the cervical canal.
The image shows the low-signal
intensity cervical stroma (arrows),
which surrounds the narrow highsignal intensity cervical canal. (Reproduced from Hamm B. et al. MRT
von Abdomen und Becken, 2nd ed.
Stuttgart: Thieme; 2006.)
Pubic
symphysis
Pubis
(body)
Pectineus
Rectus femoris
Levator ani
Iliopsoas
Femur
Obturator
externus
Sciatic n.
C
Section through the lower vagina.
(Reproduced from Moeller TB, Reif E.
Pocket Atlas of Sectional Anatomy,
Vol 2, 4th ed. New York, NY: Thieme;
2014.)
288
Ischial
tuberosity
Gluteus
maximus
Vagina
Rectum
Obturator
internus
Fig. 23.5 MRI of the female pelvis
Cervical canal
Sagittal section, left lateral view
Myometrium
Coccyx
Bladder
A
Position of the uterus with a near empty bladder.
The image shows the uterus in the first half of
the menstrual cycle (proliferative phase) with
narrow endometrium and relatively low-signal
intensity of the mymoetrium. (Reproduced from
Hamm B. et al. MRT von Abdomen und Becken,
2nd ed. Stuttgart: Thieme; 2006.)
Urethra
Levator ani
Pubic
symphysis
External anal
sphincter
Vagina
23 Sectional & Radiographic Anatomy
Rectum
Endometrium
Body of uterus
(myometrium)
Uterus (junctional
zone)
Uterus (cavity)
Uterus
(endometrium)
Rectum
Rectouterine pouch
(of Douglas)
Urinary bladder
Urethra
Vagina (wall)
B
Position of the uterus with a
full bladder. (Reproduced from
Moeller TB, Reif E. Pocket Atlas of
Sectional Anatomy, Vol 2, 4th ed.
New York, NY: Thieme; 2014.)
Pubis
Fig. 23.6 MRI of the female pelvis
Coronal section, anterior view. (Reproduced from Moeller TB, Reif E. Pocket
Atlas of Sectional Anatomy, Vol 2, 4th ed.
New York, NY: Thieme; 2014.)
Psoas major
L4 vertebra
Iliac crest
Sigmoid colon
Iliacus
Internal iliac a. and v.
Gluteus medius
Uterus
Head of femur
Urinary bladder
Obturator internus
Levator ani
Ischium, ramus
Labium minus
289
Pelvis & Perineum
Radiographic Anatomy of the Male Pelvis
Fig. 23.7 MRI of the male pelvis
Sagittal section, left lateral view.
(Reproduced from Hamm B. et al.
MRT von Abdomen und Becken,
2nd ed. Stuttgart: Thieme; 2006.)
Rectus
abdominis
Prostate
Seminal
gland
Sacrum
Rectovesical
(Denonvillier) fascia
Bladder
Ampulla of rectum
Pubic symphysis
Corpus cavernosum
of penis
Anal canal
Corpus spongiosum
of penis
Bulb of penis
Fig. 23.8 MRI of the testes
Pubis
Pubic
symphysis
Spermatic
cord
Mediastinum
testis with rete testis
Spermatic
cord
Corpus
cavernosum
of penis
Urethra
Mediastinum
of testis
Tunica
albuginea
Corpus spongiosum
of penis
Testes
A
Coronal section, anterior view. (Reproduced from Moeller TB,
Reif E. Pocket Atlas of Sectional Anatomy, Vol 2, 4th ed. New
York, NY: Thieme; 2014.)
290
Head of the
epididymis
Tunica
albuginea
Tail of the
epididymis
B
Parasagittal section, T2 W image. (Reproduced from
Krombach GA, Mahnken AH. Body Imaging: Thorax
and Abdomen. New York, NY: Thieme; 2018.)
Fig. 23.9 MRI of the prostate
(Reproduced from Krombach GA, Mahnken AH. Body Imaging: Thorax and Abdomen. New York, NY: Thieme; 2018.)
Pubis
23 Sectional & Radiographic Anatomy
Anterior
fibromuscular
connective
tissue
Transitional
zone
Prostatic
urethra
Ductus
deferens
Seminal
glands
Transitional
zone
Peripheral
zone
Coil inside
rectum
A
Transverse section, T2W image.
Obturator
internus muscle
Urethra
Peripheral
zone
B
Coronal section, T2W image.
Fig. 23.10 MRI of the male pelvis
Coronal section. (Reproduced from
Moeller TB, Reif E. Pocket Atlas of
Sectional Anatomy, Vol 2, 4th ed.
New York, NY: Thieme; 2014.)
Common iliac
a. and v.
Sigmoid colon
Urinary bladder
Head of femur
Obturator externus
muscle
Pubis
Corpus
spongiosum
Bulbospongiosus
muscle
Prostate (central
zone)
Prostate (peripheral
zone)
Prostate (transition
zone)
Ureter
Corpus cavernosum
Ischiocavernosus
muscle
291
Upper Limb
24 Surface Anatomy
28 Neurovasculature
Surface Anatomy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 294
25 Shoulder & Arm
Bones of the Upper Limb . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Clavicle & Scapula . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Humerus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Joints of the Shoulder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Joints of the Shoulder: Glenohumeral Joint . . . . . . . . . . . . . .
Subacromial Space & Bursae . . . . . . . . . . . . . . . . . . . . . . . . .
Anterior Muscles of the Shoulder & Arm (I) . . . . . . . . . . . . . .
Anterior Muscles of the Shoulder & Arm (II) . . . . . . . . . . . . .
Posterior Muscles of the Shoulder & Arm (I) . . . . . . . . . . . . .
Posterior Muscles of the Shoulder & Arm (II) . . . . . . . . . . . . .
Muscle Facts (I) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Muscle Facts (II) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Muscle Facts (III) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Muscle Facts (IV) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
296
298
300
302
304
306
308
310
312
314
316
318
320
322
26 Elbow & Forearm
Radius & Ulna . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Elbow Joint . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Ligaments of the Elbow Joint . . . . . . . . . . . . . . . . . . . . . . . . .
Radioulnar Joints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Muscles of the Forearm: Anterior Compartment . . . . . . . . .
Muscles of the Forearm: Posterior Compartment . . . . . . . . .
Muscle Facts (I) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Muscle Facts (II) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Muscle Facts (III) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
324
326
328
330
332
334
336
338
340
27 Wrist & Hand
Bones of the Wrist & Hand . . . . . . . . . . . . . . . . . . . . . . . . . . .
Carpal Bones . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Joints of the Wrist & Hand . . . . . . . . . . . . . . . . . . . . . . . . . . .
Ligaments of the Hand . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Ligaments & Compartments of the Wrist . . . . . . . . . . . . . . .
Ligaments of the Fingers . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Muscles of the Hand: Superficial & Middle Layers . . . . . . . . .
Muscles of the Hand: Middle & Deep Layers . . . . . . . . . . . . .
Dorsum of the Hand . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Muscle Facts (I) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Muscle Facts (II) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
342
344
346
348
350
352
354
356
358
360
362
Arteries of the Upper Limb . . . . . . . . . . . . . . . . . . . . . . . . . . .
Veins & Lymphatics of the Upper Limb . . . . . . . . . . . . . . . . .
Nerves of the Upper Limb: Brachial Plexus . . . . . . . . . . . . . .
Supraclavicular Branches & Posterior Cord . . . . . . . . . . . . . .
Posterior Cord: Axillary & Radial Nerves . . . . . . . . . . . . . . . .
Medial & Lateral Cords . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Median & Ulnar Nerves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Superficial Veins & Nerves of the Upper Limb . . . . . . . . . . . .
Posterior Shoulder & Arm . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Anterior Shoulder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Axilla . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Anterior Arm & Cubital Region . . . . . . . . . . . . . . . . . . . . . . . .
Anterior & Posterior Forearm . . . . . . . . . . . . . . . . . . . . . . . . .
Carpal Region . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Palm of the Hand . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Dorsum of the Hand . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
364
366
368
370
372
374
376
378
380
382
384
386
388
390
392
394
29 Sectional & Radiographic Anatomy
Sectional Anatomy of the Upper Limb. . . . . . . . . . . . . . . . . .
Radiographic Anatomy of the Upper Limb (I). . . . . . . . . . . . .
Radiographic Anatomy of the Upper Limb (II). . . . . . . . . . . .
Radiographic Anatomy of the Upper Limb (III). . . . . . . . . . . .
Radiographic Anatomy of the Upper Limb (IV) . . . . . . . . . . .
396
398
400
402
404
24
Surface Anatomy
Upper Limb
Surface Anatomy
Fig. 24.1 Regions of the upper limb
Clavipectoral
triangle
Deltoid region
Deltoid region
Infraclavicular
fossa
Clavipectoral
triangle
Axillary region
Infraclavicular
fossa
Anterior
arm region
Scapular region
Posterior
arm region
Axillary region
(axillary fossa)
Anterior
cubital region
Posterior
cubital region
Anterior
forearm
region
B Right axilla, anterior view.
Posterior
forearm
region
Anterior
carpal region
Posterior
carpal region
Palm of
the hand
Dorsum
of the hand
A
Right limb, anterior view.
CRight limb, posterior view.
Fig. 24.2 Palpable musculature
of the upper limb
Clavicle
Scapular
spine
Deltoid
Cephalic v.
(in deltopectoral
groove)
Pectoralis
major
Biceps
brachii
Deltoid
Teres major
Basilic v.
Triceps
brachii
Cephalic v.
Olecranon
Median
cubital v.
Extensor carpi
radialis longus
Brachioradialis
Flexor carpi
radialis
Flexor carpi
ulnaris
Hypothenar
eminence
A
Left limb, anterior view.
294
Long head
Lateral head
Latissimus
dorsi
Palmaris longus
tendon
Thenar eminence
Basilic v.
Extensor carpi
ulnaris
Flexor carpi
ulnaris
Extensor digitorum
tendons, dorsal
venous network
BRight limb, posterior view.
Extensor carpi
radialis longus
Cephalic v.
Extensor
digitorum
Fig. 24.3 Palpable bony prominences
of the upper limb
Coracoid process
Acromion
Greater
tubercle
Greater and lesser
tubercles
Scapular
spine
Inferior
angle
Medial
epicondyle
Lateral
epicondyle
Olecranon
24 Surface Anatomy
Except for the lunate and trapezoid bones,
all of the bones in the upper limb are
palpable to some degree through the
skin and soft tissues.
Superior angle
Clavicle
Acromion
Head of
radius
Shaft
of ulna
Tubercle of
scaphoid
DIP, distal interphalangeal;
IP, interphalangeal;
MCP, metacarpophalangeal;
PIP, proximal interphalangeal.
Styloid
process
of radius
Triquetrum bone
Hook of hamate
Tubercle of
trapezium
Fig. 24.4 Surface
anatomy of the
wrist and hand
Styloid process
of ulna
Pisiform bone
Capitate bone
Metacarpophalangeal joints
Metacarpals
Phalanges
Interphalangeal
joints
B
Right limb,
posterior view.
A
Right limb,
anterior view.
DIP joint
crease
PIP joint
crease
MCP joint
crease
Distal transverse
crease
Proximal transverse crease
IP joint
crease
Middle crease
MCP joint
crease
Hypothenar
eminence
Pisiform
Thenar
eminence
Thenar
crease
(“life line”)
A
Left palm and wrist.
Distal wrist crease
Proximal wrist
crease
Ulnar tunnel
(with ulnar a. and n.)
Palmar
carpal lig.
BPalm and wrist showing
the carpal and ulnar tunnels.
Flexor retinaculum
(roof of carpal tunnel)
Palmar
aponeurosis (cut)
Median n.
295
25
Shoulder & Arm
Upper Limb
Bones of the Upper Limb
Fig. 25.1 Bones of the upper limb
Right limb. The upper limb is subdivided into three regions: arm,
forearm, and hand. The shoulder girdle (clavicle and scapula) joins the
upper limb to the thorax at the sternoclavicular joint.
Clavicle
Clavicle
Acromioclavicular joint
Shoulder joint
Shoulder
girdle
Scapula
Arm
Scapula
Scapular
spine
Humerus
Humerus
Elbow
joint
Olecranon
Head of radius
Forearm
Radius
Radius
Ulna
Ulna
1st
metacarpal
Carpals
Carpal bones
Metacarpals
Hand
4th proximal phalanx
Phalanges
4th middle phalanx
4th distal phalanx
A
Anterior view.
296
B
Posterior view.
Fig. 25.2 Bones of the shoulder girdle in normal
relation to those of the trunk
Acromion
Acromion
Clavicle
Coracoid
process
Clavicle
Sternoclavicular
joint
Glenoid
cavity
Coracoid
process
Manubrium
Scapula,
costal surface
25 Shoulder & Arm
First rib
Body of
sternum
Scapula
Inferior
angle
Superior
angle
Humerus
Clavicle
A
Anterior view.
Acromion
Scapula,
posterior surface
Medial border
Inferior angle
Ulna
Acromioclavicular joint
Radius
First rib
Clavicle
Acromion
Coracoid process
1st
metacarpal
2nd
metacarpal
1st proximal
phalanx
1st distal
phalanx
B
Posterior view.
Glenoid cavity
Scapula,
posterior
surface
Lateral
border
Phalanges
C
Lateral view.
C
Lateral view.
297
Upper Limb
Clavicle & Scapula
The shoulder girdle (clavicle and scapula) connects the bones of the
upper limb to the thoracic cage. Whereas the pelvic girdle (paired hip
bones) is firmly integrated into the axial skeleton (see p. 230), the
shoulder girdle is extremely mobile.
Fig. 25.3 Shoulder girdle in situ
Right shoulder, superior view.
Suprascapular
fossa
Acromion
Acromioclavicular
joint
Coracoid
process
Clavicle
Fig. 25.4 Clavicle
Right clavicle. The S-shaped clavicle is visible and
palpable along its entire length (generally 12 to
15 cm). Its medial end articulates with the sternum
at the sternoclavicular joint. Its lateral end articulates with the scapula at the acromio­clavicular joint
(see Fig. 25.3).
Sternoclavicular
joint
Manubrium
Conoid
tubercle
Acromial
end
Sternal
articular surface
Shaft of
clavicle
Sternal
end
Superior view.
A
Sternal
end
Acromial
articular surface
Impression for
costoclavicular lig.
Acromial
end
B
Inferior view.
298
Groove for
subclavius muscle
Conoid
tubercle
Acromion
Coracoid
process
Scapular
notch
Superior
border
Fig. 25.5 Scapula
Superior
angle
Right scapula. In its normal anatomical position,
the scapula extends from the 2nd to the 7th rib.
25 Shoulder & Arm
Subscapular
fossa
Supraglenoid
tubercle
Acromion
Lateral
angle
Superior angle
Glenoid
cavity
Coracoid
process
Infraglenoid
tubercle
Supraglenoid
tubercle
Glenoid
cavity
Neck
Medial
border
Lateral
border
Infraglenoid
tubercle
Lateral
border
Posterior
surface
A
Anterior view.
Costal
surface
Inferior angle
Superior
angle
Superior
border
Scapular
notch
Scapular
spine
Coracoid
process
Acromion
Inferior angle
B
Right lateral view.
Supraspinous
fossa
Acromial
angle
Glenoid
cavity
Infraglenoid
tubercle
Medial
border
Infraspinous
fossa
Lateral
border
Clinical box 25.1
Scapular foramen
The superior transverse ligament of the
scapula (see Fig. 25.14) may become ossified,
transforming the scapular notch into an anomalous
bony canal, the scapular foramen. This can lead to
compression of the suprascapular nerve as it passes
through the canal (see p. 381).
Scapular foramen
Inferior angle
Posterior view.
C
299
Upper Limb
Humerus
Fig. 25.6 Humerus
Right humerus. The head of the humerus articulates with the scapula at
the glenohumeral joint (see p. 302). The capitulum and trochlea of the
Greater Intertubercular Lesser
groove
tubercle
tubercle
Anatomical
neck
humerus articulate with the radius and ulna, respectively, at the elbow
(cubital) joint (see p. 326).
Greater
tubercle
Intertubercular
groove
Head of
humerus
Lesser
tubercle
Anatomical neck
Greater
tubercle
Head of
humerus
Anatomical neck
Surgical
neck
Surgical
neck
Crest of
lesser
tubercle
Crest of
greater
tubercle
Radial
groove
(for radial n.)
Deltoid
tuberosity
Shaft of
humerus,
posterior
surface
Anterolateral
surface
Shaft of humerus,
anterolateral
surface
Anteromedial
surface
Lateral
supracondylar
ridge
Medial
supracondylar
ridge
Lateral
border
Lateral
supracondylar
ridge
Medial
supracondylar
ridge
Lateral
border
Coronoid
fossa
Radial
fossa
Medial
epicondyle
Lateral
Capitulum Trochlea
epicondyle
Condyle of humerus
A
Anterior view.
300
Medial
border
Lateral
supracondylar
ridge
Radial fossa
Medial
epicondyle
Capitulum
Lateral epicondyle
B
Lateral view.
Ulnar groove
(for ulnar n.)
Olecranon Trochlea
fossa
C
Posterior view.
Lateral
epicondyle
Fractures of the humerus
Anterior view. Fractures of the proximal
humerus are very common and occur
predominantly in older patients who sustain
a fall onto the outstretched arm or directly
onto the shoulder. Three main types are
distinguished.
Anatomical Head of
neck
humerus
Lesser
tubercle
Crest of
lesser
tubercle
Head of
humerus
Anatomical
neck
Greater
tubercle
Lesser
tubercle
Intertubercular
groove
Surgical
neck
25 Shoulder & Arm
Clinical box 25.2
Greater
tubercle
A
Extra-articular fracture.
Intertubercular
groove
Lesser
tubercle
Head of
humerus
E
Proximal (superior) view.
Anatomical
neck
Shaft of
humerus,
anteromedial
surface
Capitulum
Lateral
epicondyle
Medial
border
Olecranon fossa
Ulnar
groove
B
Intra-articular fracture.
Medial epicondyle
F
Distal (inferior) view.
Comminuted fracture.
C
Medial
supracondylar
ridge
Olecranon
fossa
Trochlea
of humerus
Medial epicondyle
DMedial view.
Capitulotrochlear
Trochlea
groove
Extra-articular fractures and intra-articular
fractures are often accompanied by injuries
of the blood vessels that supply the humeral
head (anterior and posterior circumflex
humeral arteries), with an associated risk of
post-traumatic avascular necrosis.
Fractures of the surgical neck can damage
the axillary nerve and fractures of the
humeral shaft and distal humerus are
frequently associated with damage to the
radial nerve.
301
Upper Limb
Joints of the Shoulder
Fig. 25.7 Joints of the shoulder: Overview
Right shoulder, anterior view.
Acromioclavicular
joint
Subacromial
space
Scapulothoracic
joint
Sternoclavicular
joint
Glenohumeral
joint
Fig. 25.8 Joints of the shoulder girdle
Right side, superior view.
Acromioclavicular
joint (with acromioclavicular lig.)
Coracoacromial lig.
Fig. 25.9 Scapulothoracic joint
Right side, superior view. In all movements
of the shoulder girdle, the scapula glides on a
curved surface of loose connective tissue between the serratus anterior and the subscapularis muscles. This surface can be considered a
scapulothoracic joint.
Scapulothoracic
joint
Subscapularis
Acromion
Head of
humerus
Coracoid
process
Serratus
anterior
Clavicle
302
Glenohumeral
joint
Superior posterior
serratus
Scapulothoracic
joint
Posterior
sternoclavicular lig.
Sternoclavicular joint
(with anterior
sternoclavicular lig.)
Fig. 25.10 Sternoclavicular joint
Anterior
sternoclavicular lig.
Clavicle
Costal
cartilage
Fig. 25.11 Acromioclavicular joint
Anterior view. The acromioclavicular joint is a
plane joint. Because the articulating surfaces
are flat, they must be held in place by strong
ligaments, greatly limiting the mobility of the
joint.
Acromioclavicular lig.
Interclavicular
lig.
Articular
disk
Costoclavicular lig.
1st rib
25 Shoulder & Arm
Anterior view with sternum coronally sectioned
(left). Note: A fibrocartilaginous articular disk
compensates for the mismatch of surfaces between the two saddle-shaped articular facets of
the clavicle and the manubrium.
Clavicle,
acromial
end
Manubrium
Coracoclavicular lig.
Trapezoid
lig.
Conoid
lig.
Sternocostal
joint
Clavicle,
sternal end
Acromion
Coracoacromial
arch
Coracoacromial lig.
Superior angle
Coracoid process
Superior transverse
lig. of scapula
Head of humerus
Scapular notch
Greater tubercle
Lesser tubercle
Intertubercular groove
Scapula, costal
(anterior) surface
Glenoid
cavity
Medial
border
Humerus
Clinical box 25.3
Injuries of the acromioclavicular joint
A fall onto the outstretched arm or shoulder frequently causes dislocation of the acromioclavicular joint (often known as a “shoulder separation”) and damage to
the coracoclavicular ligaments.
A
Stretching of acromio­
clavicular ligaments.
B
Rupture of acromioclavicular ligament.
C
Complete dislocation of acromioclavicular joint. Note rupture of acromioclavicular and coracoclavicular ligaments.
303
Upper Limb
Joints of the Shoulder: Glenohumeral Joint
Fig. 25.12 Glenohumeral joint: Bony elements
Right shoulder.
Coracoid
process
Supraglenoid
tubercle
Clavicle
Scapular
notch
Scapular
notch
Scapular
spine
Clavicle
Acromion
Acromion
Head of humerus
Lesser
tubercle
Head of
humerus
Greater
tubercle
Greater
tubercle
Glenoid
cavity
Intertubercular
groove
Anatomical
neck
Infraglenoid
tubercle
Infraspinous
fossa
Lateral
border of
scapula
A
Anterior view.
Humerus
B
Posterior view.
Fig. 25.13 Glenohumeral joint cavity
AcromioCoracoclavicular
acromial lig.
lig.
Acromion
Acromion
Coracoid
process
Scapular
spine
Greater
tubercle
Coracoclavicular
lig.
Coracoid
process
Superior
transverse
lig. of
Clavicle scapula
Subcoracoid
bursa
Synovial
membrane
Lesser
tubercle
Transverse
lig. of
humerus
Humerus
C
Lateral view.
304
Axillary
recess
IntertuberTendon of
Subtendinous
biceps brachii, Intertubercular cular synovial
bursa of
groove
sheath
long head
subscapularis
Fig. 25.14 Glenohumeral joint: Capsule and ligaments
Right shoulder.
Superior transverse
lig. of scapula
Clavicle
Coracoacromial
lig.
Acromion
Coracoacromial
arch
Scapular
notch
Coracoclavicular lig. Clavicle
Acromioclavicular lig.
Scapular
notch
Coracoid
process
Acromion
Coracohumeral
lig.
Greater
tubercle
25 Shoulder & Arm
Acromioclavicular Coracoclavicular
lig.
lig.
Intertubercular
synovial sheath
Intertubercular
groove
Axillary
recess
Neck of
scapula
Lateral
border
Joint capsule,
glenohumeral ligs.
A
Anterior view.
Humerus
Axillary
recess
Scapula,
costal surface
Infraspinous
fossa
Scapular
spine
Joint
capsule
B
Posterior view.
Fig. 25.15 Ligaments reinforcing capsule
Schematic representation of the ligaments reinforcing the capsule after removal of the humeral head.
Right shoulder.
Glenoid
cavity
Acromion
Coracoacromial
lig.
Supraspinatus
Tendon of biceps
brachii, long head
Tendon of biceps
brachii, long head
Coracohumeral
lig.
Coracohumeral
lig.
Superior glenohumeral lig.
Superior
glenohumeral
lig.
Subscapularis
Middle glenohumeral lig.
Middle
glenohumeral
lig.
Posterior
band
Axillary
recess
Anterior
band
Inferior glenohumeral lig.
Lateral view.
A
Anatomic neck
of humerus
Inferior
glenohumeral
lig.
Triceps brachii,
long head
Posterior view.
B
305
Upper Limb
Subacromial Space & Bursae
Fig. 25.16 Subacromial space
Fig. 25.17 Subacromial bursa and glenoid cavity
Right shoulder.
Right shoulder, lateral view of sagittal section with humerus removed.
Coracoacromial arch
Coracoacromial arch
Acromion
Coracoacromial
lig.
Acromion
Coracoid
process
Coracoacromial Coracoid
lig.
process
Supraspinatus
Subacromial
bursa
Subtendinous bursa
of subscapularis
Subdeltoid
bursa
Subacromial
bursa
Infraspinatus
Subtendinous
bursa of
subscapularis
Greater tubercle
Transverse lig.
of humerus
Intertubercular
tendon sheath
Infraspinatus
Subtendinous
bursa of
infraspinatus
Tendon of
biceps brachii,
long head
Glenoid cavity
Subscapularis
Glenoid labrum
Joint capsule
Teres minor
Axillary recess
Teres minor
Biceps brachii,
short head
Humerus
Infraspinatus
Subscapularis
Biceps brachii,
long head
Lateral border
of scapula
A
Lateral view.
Supraspinatus
Scapula
Superior transverse
lig. of scapula
Acromial articular
surface
Acromion
Subacromial
bursa
Coracoacromial
lig.
Subdeltoid
bursa
Coracoid
process
Coracoacromial arch
Greater tubercle
306
Intertubercular
groove
Joint capsule
Lesser tubercle
Humerus
B
Superior view. Note the position of the subacromial bursa between the supraspinatus
muscle and the coracoacromial arch.
Fig. 25.18 Subacromial and subdeltoid bursae
Right shoulder, anterior view.
Acromioclavicular
lig.
25 Shoulder & Arm
Subcutaneous acromial
Coracoacromial
Coracoacromial
bursa
arch
lig.
Trapezius
Acromion
Coracoclavicular lig.
Coracoid
process
Clavicle
Subacromial
bursa
Superior transverse
lig. of scapula
Subdeltoid
bursa
1st rib
Glenohumeral
joint capsule
Subtendinous bursa
of subscapularis
Deltoid
Tendon sheath
in intertubercular
groove
Subscapularis
Humerus
A
Location of bursae.
Biceps brachii, Biceps brachii, Coraco- Teres
long head
short head
brachialis major
Skin
Subcutaneous tissue
Trapezius
Acromion
Supraspinatus
tendon
Head of humerus
Subdeltoid
bursa
Subacromial
bursa
Supraspinatus
Glenoid
cavity
Scapula
Subscapularis
Glenoid labrum
Deltoid
Axillary recess
Teres major
Latissimus dorsi
B
Coronal section. The arrows are
pointing at the supraspinatus
tendon, which is frequently
injured in a “rotator cuff tear”
(for rotator cuff, see p. 317).
Humerus
307
Upper Limb
Anterior Muscles of the Shoulder & Arm (I)
Fig. 25.19 Anterior muscles of the shoulder and arm
Right side, anterior view. Muscle origins are shown in red,
insertions in blue.
1st rib
Clavicle
Trapezius
Vertebra prominens
(C7)
Sternocleidomastoid
Deltoid
Manubrium
Clavicular
part
Coracobrachialis
Sternocostal
part
Teres major
Latissimus dorsi
Abdominal
part
Long
head
Biceps
brachii
Short
head
Body of
sternum
Serratus
anterior
Rectus sheath
Biceps brachii
Brachialis
Medial
epicondyle
A
Superficial dissection.
308
External oblique
Pectoralis
major
Clavicular part
Deltoid
25 Shoulder & Arm
Supraspinatus
Pectoralis
minor
Trapezius
Subclavius
Clavicle
Acromial part
Sternocleidomastoid
Coracoid process
Greater tubercle
Pectoralis major,
clavicular part
Subscapularis
Sternum,
manubrium
Pectoralis major
Coracobrachialis
Costal
cartilage
Deltoid
Teres major
Biceps
brachii
Sternum, body
Serratus
anterior
Long
head
Pectoralis major,
sternocostal part
Short
head
Latissimus
dorsi
Sternum, xiphoid
process
T12 vertebral
body
Lateral
epicondyle
Costal arch
(margin)
Brachialis
Medial
epicondyle
B
Deep dissection. Removed: Sternocleidomastoid, trapezius, pectoralis
major, deltoid, and external oblique muscles.
309
Upper Limb
Anterior Muscles of the Shoulder & Arm (II)
Fig. 25.20 Anterior muscles of the shoulder and arm:
Dissection
Right arm, anterior view. Muscle origins are shown in red, insertions
in blue.
Subclavius
Deltoid
Trapezius
Supraspinatus
Supraspinatus
Serratus
anterior
Serratus
anterior
Pectoralis
minor
Coracobrachialis
Coracobrachialis
Pectoralis
major
Pectoralis
major
Latissimus
dorsi
Biceps
brachii,
short head
Biceps
brachii,
short head
Biceps
brachii,
long
head
Biceps
brachii,
long
head
Teres
major
Subscapularis
Teres
major
Pronator teres
Common head of
superficial flexors
Brachialis
Brachialis
Biceps
brachii
tendon
Bicipital
aponeurosis
A
Removed: Thoracic skeleton. Partially removed: Latissimus dorsi and
serratus anterior.
310
Biceps
brachii
tendon
Bicipital
aponeurosis
B
Removed: Latissimus dorsi and serratus anterior.
Subscapularis
Biceps brachii,
short head,
and coracobrachialis
Biceps brachii,
short head
Supraspinatus
Supraspinatus
Subscapularis
Subscapularis
Subclavius
Trapezius
Serratus
anterior
25 Shoulder & Arm
Pectoralis
minor
Deltoid
Intertubercular groove
Latissimus
dorsi
Latissimus
dorsi
Biceps
brachii,
long head
Teres major
Pectoralis
major
Pectoralis
major
Biceps
brachii,
long head
Deltoid
Deltoid
Coracobrachialis
Teres major
Coracobrachialis
Subscapularis
Subscapularis
Brachialis
Brachialis
Brachioradialis
Extensor carpi
radialis longus
Extensor carpi
radialis brevis
Common head
of extensors
Pronator teres
Common head of
superficial flexors
Brachialis
Biceps brachii,
radial tuberosity
Supinator
Biceps brachii
Flexor digitorum
profundus
C
Removed: Subscapularis and supraspinatus. Partially removed: Biceps
brachii.
DRemoved: Biceps brachii, coracobrachialis, and teres major.
311
Upper Limb
Posterior Muscles of the Shoulder & Arm (I)
Fig. 25.21 Posterior muscles of
the shoulder and arm
Right side, posterior view.
Semispinalis
capitis
Sternocleidomastoid
Splenius
capitis
Descending
part
Trapezius
Transverse
part
Scapular spine
Deltoid
Ascending
part
Teres major
Long
head
Triceps
brachii
Lateral
head
Latissimus
dorsi
Extensor carpi
radialis brevis
Extensor carpi
radialis longus
Olecranon
Anconeus
External
oblique
Thoracolumbar
fascia
Flexor
carpi ulnaris
Extensor
carpi ulnaris
Extensor
digitorum
A
Superficial dissection.
312
Iliac
crest
Internal
oblique
25 Shoulder & Arm
Superior
nuchal line
Sternocleidomastoid
Semispinalis
capitis
Splenius capitis
Splenius cervicis
Rhomboid minor
Levator scapulae
Rhomboid major
Clavicle
Acromion
Supraspinatus
Trapezius
(cut )
Scapular spine
Scapula, medial border
Infraspinatus
Teres minor
Teres major
Intrinsic back muscles,
thoracolumbar fascia,
posterior layer
Latissimus
dorsi (cut)
Serratus
anterior
Serratus
posterior inferior
Latissimus dorsi
(cut)
B
Deep dissection. Partially removed: Trapezius and latissimus dorsi.
External oblique
Thoracolumbar fascia,
posterior layer
Internal
oblique
313
Upper Limb
Posterior Muscles of the Shoulder & Arm (II)
Fig. 25.22 Posterior muscles of the shoulder
and arm: Dissection
Right arm, posterior view. Muscle origins are shown in red,
insertions in blue.
Rhomboid
minor
Levator
scapulae
Supraspinatus
Supraspinatus
Trapezius
Deltoid
(clavicular part)
Deltoid
Deltoid
(acromial
part)
Deltoid
(spinal part)
Teres minor
Infraspinatus
Infraspinatus
Teres
minor
Teres major
Rhomboid
major
Triceps
brachii,
medial head
Teres major
Triceps
brachii,
lateral head
Latissimus dorsi
(scapular part)
Triceps brachii,
long head
Triceps
brachii,
lateral head
Triceps brachii,
long head
Brachioradialis
Extensor
carpi radialis longus
Extensor
carpi radialis brevis
Olecranon
Anconeus
Flexor
carpi ulnaris
Extensor
carpi ulnaris
Extensor carpi
radialis brevis
Common head
of extensors
Common head of
superficial flexors
Anconeus
Flexor
carpi ulnaris
Flexor digitorum
profundus
Extensor
digitorum
A
Removed: Rhomboids major and minor,
serratus anterior, and levator scapulae.
314
B
Removed: Deltoid and forearm muscles.
Supinator
Rhomboid
minor
Levator
scapulae
Supraspinatus
Trapezius
Deltoid
(clavicular part)
25 Shoulder & Arm
Supraspinatus
Deltoid
(acromial part)
Supraspinatus
Supraspinatus
Infraspinatus
Infraspinatus
Teres
minor
Teres
minor
Deltoid
(spinal part)
Triceps
brachii,
lateral head
Triceps
brachii,
long head
Teres minor
Teres minor
Infraspinatus
Teres major
Triceps brachii,
long head
Infraspinatus
Teres major
Deltoid
Brachialis
Triceps
brachii,
lateral head
Rhomboid
major
Latissimus dorsi
(scapular part)
Triceps
brachii,
medial head
Radial
groove
Deltoid
Brachialis
Triceps
brachii,
medial head
Triceps
brachii,
lateral head
(cut edge)
Extensor carpi
radialis longus
Brachioradialis
Extensor carpi
radialis brevis
Common head
of extensors
Common head of
superficial flexors
Triceps brachii
Anconeus
C
Removed: Supraspinatus, infraspinatus, and teres minor. Partially
removed: Triceps brachii.
DRemoved: Triceps brachii and teres major.
315
Upper Limb
Muscle Facts (I)
The actions of the three parts of the deltoid muscle depend on their
relationship to the position of the humerus and its axis of motion. At
less than 60 degrees, the muscles act as adductors, but at greater than
60 degrees, they act as abductors. As a result, the parts of the deltoid
can act antagonistically as well as synergistically.
Acromion
Fig. 25.23 Deltoid
Right shoulder.
Clavicle
Scapular
spine
DS
Deltoid,
clavicular
part
Deltoid,
acromial part
A
Deltoid,
spinal part
Scapula
A
Parts of the deltoid, right lateral view, schematic.
Acromion
B
Right lateral view.
Deltoid,
clavicular part
Shaft of Deltoid
humerus tuberosity
Clavicle
Coracoid
Deltoid,
process clavicular part
Deltoid,
acromial part
Acromion
Clavicle
Scapula,
costal
surface
Deltoid,
acromial
part
Scapular
spine
Deltoid,
spinal
part
Scapula,
posterior
surface
Deltoid
tuberosity
Deltoid
tuberosity
Shaft of
humerus
Shaft of
humerus
C
Anterior view.
Table 25.1
DPosterior view.
Parts of the deltoid
Muscle
Deltoid
Origin
① Clavicular (anterior) part
Lateral one third of clavicle
② Acromial (lateral) part
Acromion
③ Spinal (posterior) part
Scapular spine
Insertion
Innervation
Humerus (deltoid
tuberosity)
Axillary n. (C5, C6)
Flexion, internal rotation, adduction
* Between 60 and 90 degrees of abduction, the clavicular and spinal parts assist the acromial part with abduction.
316
Action*
Abduction
Extension, external rotation, adduction
A
Fig. 25.24 Rotator cuff
Right shoulder. The rotator cuff consists of four muscles: supraspinatus,
infraspinatus, teres minor, and subscapularis.
F
Acromion
Supraspinatus
Coracoid
process
Greater
tuberosity
A
Posterior view, schematic.
Acromion
Coracoid
process
Subscapularis
Infraspinatus
B
Anterior view, schematic.
25 Shoulder & Arm
S
D
Teres
minor
Scapular Supra- Superior
notch spinatus border
Shaft of
humerus
Superior angle
Scapula,
lateral
border
Greater
tubercle
Lesser
tubercle
Intertubercular groove
Scapula,
inferior
angle
Medial border
Crest of greater
tubercle
DLateral view.
Subscapularis
Crest of lesser
tubercle
Supraspinatus
Scapular
spine
Coracoid
process
Acromion
Superior
angle
Greater
tubercle
Shaft of humerus
Inferior angle
C
Anterior view.
Medial
border
Infraspinatus
Teres
minor
Shaft of
humerus
Lateral border
E
Posterior view.
Table 25.2
Muscle
Muscles of the rotator cuff
Origin
Insertion
① Supraspinatus
Supraspinous fossa
② Infraspinatus
Infraspinous fossa
③ Teres minor
④ Subscapularis
Inferior angle
Scapula
Lateral border
Subscapular fossa
Humerus
Innervation
Action
Initiates abduction
Humerus (greater
tubercle)
Suprascapular n. (C4–C6)
Axillary n. (C5, C6)
External rotation, weak adduction
Humerus (lesser
tubercle)
Upper and lower
subscapular nn. (C5, C6)
Internal rotation
External rotation
317
Upper Limb
Muscle Facts (II)
Fig. 25.25 Pectoralis major and
coracobrachialis
Anterior view.
Acromion
F
A
Pectoralis major,
clavicular part Clavicle
Coracoid
process
S
Lesser
tubercle
D
Intertubercular
groove
Pectoralis
major,
sternocostal
part
Crest of greater
tubercle
Sternum
Coracobrachialis
A
Schematic.
Pectoralis major,
abdominal part
Humerus
Clavicular
part
Sternocostal
part
Abdominal
part
C
Pectoralis major and coracobrachialis.
B
Pectoralis major in neutral position (left)
and elevation (right).
Table 25.3
Pectoralis major and coracobrachialis
Muscle
Pectoralis major
④ Coracobrachialis
318
Origin
① Clavicular part
Clavicle (medial half)
② Sternocostal part
Sternum and costal cartilages 1–6
③ Abdominal part
Rectus sheath (anterior layer)
Scapula (coracoid process)
Insertion
Innervation
Action
Humerus (crest of greater
tubercle)
Medial and lateral
pectoral nn.
(C5–T1)
Entire muscle: adduction, internal
rotation
Clavicular and sternocostal parts:
flexion; assist in respiration when
shoulder is fixed
Humerus (in line with
crest of lesser tubercle)
Musculocutaneous
n. (C5–C7)
Flexion, adduction, internal
rotation
Fig. 25.26 Subclavius and
pectoralis minor
Clavicle
Right side, anterior view.
1st rib
A
25 Shoulder & Arm
S
Acromion
Coracoid
process
Subclavius
A
Schematic.
Pectoralis
minor
Fig. 25.27 Serratus anterior
Right lateral view.
3rd
through
5th ribs
Coracoid
process
Acromion
1st rib
Glenoid
cavity
Medial
border
B
Subclavius and
pectoralis minor.
Scapula
Serratus
anterior
Inferior
angle
D
F
G
9th rib
A
Serratus anterior.
Table 25.4
B
Schematic.
Subclavius, pectoralis minor, and serratus anterior
Muscle
Origin
Insertion
Innervation
Action
① Subclavius
1st rib
Clavicle (inferior surface)
N. to subclavius (C5, C6)
Steadies the clavicle in the sternoclavicular joint
② Pectoralis minor
3rd to 5th ribs
Coracoid process
Medial pectoral n. (C8, T1)
Draws scapula downward, causing inferior
angle to move posteromedially; rotates glenoid
inferiorly; assists in respiration
Scapula (costal and dorsal surfaces of
superior angle)
③ Superior part
Serratus
anterior
④ Intermediate
part
⑤ Inferior part
1st to 9th ribs
Scapula (costal surface of medial
border)
Scapula (costal surface of medial
border and costal and dorsal surfaces
of inferior angle)
Superior part: lowers the raised arm
Long thoracic n. (C5–C7)
Entire muscle: draws scapula laterally forward;
elevates ribs when shoulder is fixed
Inferior part: rotates inferior angle of scapula
laterally forward (allows elevation of arm above
90°)
319
Muscle Facts (III)
Upper Limb
Fig. 25.28 Trapezius
Posterior view.
External occipital
protuberance
Superior
nuchal line
A
Nuchal lig.
S
Trapezius
(descending part)
C7 spinous process
Trapezius
(transverse part)
D
Acromion
Scapular spine
B
Schematic.
Trapezius
(ascending
part)
C1 (atlas)
C1–C4
transverse processes
C2 (axis)
A
Trapezius.
Levator scapulae
Rhomboid minor
T12 spinous
process
Fig. 25.29 Levator scapulae
with rhomboids major
and minor
Superior
Clavicle
angle
C7 spinous
process
Acromion
T1–T4
spinous
processes
Right side, posterior view.
Scapular
spine
Medial
border
Rhomboid
major
F
G
Scapula,
posterior
surface
Inferior
angle
H
A
Schematic.
Table 25.5
Trapezius, levator scapulae, and rhomboids major and minor
Muscle
Origin
Insertion
① Descending
part
Occipital bone; spinous
processes of C1–C7
Clavicle (lateral one
third)
②T
ransverse
part
Aponeurosis at T1–T4
spinous processes
Acromion
③ Ascending
part
Spinous processes of
T5–T12
Scapular spine
④ Levator scapulae
Transverse processes of
C1–C4
Scapula (superior
angle)
Dorsal scapular n. and
cervical spinal nn. (C3–C4)
Draws scapula medially upward while moving inferior
angle medially; inclines neck to same side
⑤ Rhomboid minor
Spinous processes of
C6, C7
Spinous processes of
T1–T4 vertebrae
Dorsal scapular n. (C4–C5)
Steadies scapula; draws scapula medially upward
⑥ Rhomboid major
Medial border of
scapula above (minor)
and below (major)
scapular spine
Trapezius
CN, cranial nerve.
320
B
Levator scapulae with rhomboids
major and minor.
Innervation
Action
Draws scapula obliquely upward; rotates glenoid cavity
superiorly; tilts head to same side and rotates it to
opposite
Accessory n. (CN XI);
C3–C4 of cervical plexus
Draws scapula medially
Draws scapula medially downward
Entire muscle: steadies scapula on thorax
Fig. 25.30 Latissimus dorsi and teres major
Posterior view.
Latissimus dorsi
(scapular part)
Humerus
T7 spinous
processes
25 Shoulder & Arm
Scapula
Teres major
Latissimus dorsi
(vertebral part)
S
A
D
Latissimus dorsi
(iliac part)
Thoracolumbar
fascia
F
Iliac crest
Ilium
Sacrum
A
Latissimus dorsi, schematic.
B
Latissimus dorsi and
teres major.
Acromion
Coracoid
process
Clavicle
Intertubercular groove
DInsertion of the latisCrest of lesser
simus dorsi on the
tubercle
floor of the intertubercular groove
Teres major
and the teres major
on the crest of the
Latissimus
lesser tubercle of the
dorsi
humerus.
G
C
Teres major, schematic.
Table 25.6
Origin
①V
ertebral
part
Spinous processes of T7–T12
vertebrae; thoracolumbar fascia
② Scapular part
Scapula (inferior angle)
③ Costal part
9th to 12th ribs
④ Iliac part
Iliac crest (posterior one third)
⑤ Teres major
Inferior
angle
Latissimus dorsi and teres major
Muscle
Latissimus
dorsi
Scapula,
costal surface
Scapula (inferior angle)
Insertion
Innervation
Action
Floor of the intertubercular
groove of the humerus
Thoracodorsal n.
(C6–C8)
Internal rotation, adduction,
extension, respiration
(“cough muscle”)
Crest of lesser tubercle of the
humerus (anterior angle)
Lower subscapular n.
(C5, C6)
Internal rotation, adduction,
extension
321
Upper Limb
Muscle Facts (IV)
The anterior and posterior muscles of the arm may be classified
respectively as flexors and extensors relative to the movement of the
elbow joint. Although the coracobrachialis is topographically part of the
anterior compartment, it is functionally grouped with the muscles of
the shoulder (see p. 318).
Fig. 25.31 Biceps brachii
and brachialis
Scapula,
anterior surface
Supraglenoid
tubercle
Coracoid
process
Right arm, anterior view.
Greater
tubercle
Lesser
tubercle
A
S
Intertubercular groove
D
Biceps brachii,
long head
Shaft of
humerus
Biceps
brachii,
short head
A
Schematic.
Brachialis
Biceps
brachii
Medial
epicondyle
Brachialis
Lateral
epicondyle
Bicipital aponeurosis
Radial tuberosity,
biceps brachii
tendon
B
Biceps brachii and brachialis.
Table 25.7
C
Brachialis.
Origin
Insertion
① Long
head
Supraglenoid tubercle of scapula
②S
hort
head
Coracoid process of scapula
③ Brachialis
Ulnar
tuberosity
Anterior muscles: Biceps brachii and brachialis
Muscle
Biceps
brachii
Radial
tuberosity
Ulnar tuberosity,
brachialis tendon
Humerus (distal half of anterior
surface)
Innervation
Action
Radial tuberosity
and bicipital
aponeurosis
Musculocutaneous n. (C5–C6)
Elbow joint: flexion; supination*
Shoulder joint: flexion; stabilization of humeral
head during deltoid contraction; abduction and
internal rotation of the humerus
Ulnar tuberosity
Musculocutaneous n. (C5–C6)
and radial n. (C7, minor)
Flexion at the elbow joint
* Note: When the elbow is flexed, the biceps brachii acts as a powerful supinator because the lever arm is almost perpendicular to the axis of pronation/supination.
322
Fig. 25.32 Triceps brachii and anconeus
Right arm, posterior view.
Scapular
spine
Lateral head
tendon of origin
Acromion
Long
head
A
Radial groove
Greater
tubercle
Infraglenoid
tubercle
D
25 Shoulder & Arm
Scapula,
posterior surface
S
Medial head
F
Tendon of
insertion
Shaft of
humerus
Triceps brachii,
medial head
Lateral
border
Triceps brachii,
long head
Triceps brachii,
lateral head
DSchematic.
Anconeus
B
Partially removed:
Lateral head of
triceps brachii.
Shaft of
humerus
Long head
tendon of
origin
Lateral
head
Medial head
Medial
epicondyle
Lateral
epicondyle
Olecranon
Anconeus
Tendon of
insertion
Anconeus
Ulna
Radius
A
Triceps brachii and anconeus.
Table 25.8
Posterior muscles: Triceps brachii and anconeus
Muscle
Triceps
brachii
Origin
① Long head
Scapula (infraglenoid tubercle)
② Medial
head
Posterior humerus, distal to radial groove; medial intermuscular septum
③ Lateral
head
Posterior humerus, proximal to radial groove; lateral intermuscular septum
④ Anconeus
C
Partially removed:
Long head of
triceps brachii.
Lateral epicondyle of humerus (variance: posterior joint capsule)
Insertion
Olecranon of ulna
Olecranon of ulna
(radial surface)
Innervation
Radial n.
(C6–C8)
Action
Elbow joint: extension
Shoulder joint, long head:
extension and adduction
Extends the elbow and
tightens its joint
323
26
Elbow & Forearm
Upper Limb
Radius & Ulna
Fig. 26.1 Radius and ulna
Right forearm.
Olecranon
Trochlear notch
Articular
fovea
Head of radius,
articular
circumference
Head of radius,
articular
circumference
Coronoid
process
Neck of
radius
Radial
notch
Radial
notch
Radial
tuberosity
Coronoid
process
Ulnar
tuberosity
Anterior
border
Shaft of ulna,
anterior
surface
Neck of
radius
Radial
tuberosity
Posterior
border
Medial
surface
Interosseous
border
Interosseous
border
Posterior
border
Shaft of radius,
anterior surface
Posterior
surface
Lateral
surface
Articular
circumference
Styloid process
of radius
A
Anterior view.
324
Carpal articular
surface
Head of
ulna
Styloid process
of ulna
Dorsal
tubercle
Head of
ulna
Styloid process
of ulna
B
Posterior view.
Styloid process
of radius
Posterior
Proximal
radioulnar joint
Olecranon
Trochlear
notch
Trochlear
notch
Proximal
radioulnar joint
Cartilage-free
strip
Articular
fovea
Coronoid
process
Head of
radius
Head of radius,
Articular
articular
fovea
circumference
Radial
notch
26 Elbow & Forearm
Olecranon
Coronoid
process
DProximal (superior) view.
Ulnar
tuberosity
Radial
tuberosity
Posterior
Posterior
Radial
Ulnar
Posterior
surface interosseous interosseous surface
border
border
Shaft of ulna,
anterior surface
Anterior
border
Radius
Lateral
surface
Anterior
border
Anterior
surface
Ulna
Interosseous
membrane Anterior
surface
Medial
surface
E
Transverse section, proximal view.
Shaft of radius,
anterior surface
Interosseous
border
Interosseous
membrane
Carpal articular
surface
Distal radioulnar
joint
Anterior
Head of ulna
Head of ulna
Styloid process
of radius
C
Anterosuperior view.
Distal radioulnar
joint
Styloid process
of radius
Dorsal
tubercle
Ulnar notch
of radius
Styloid process
of ulna
F
Distal (inferior) view.
325
Upper Limb
Elbow Joint
Fig. 26.2 Elbow (cubital) joint
Right limb. The elbow consists of three articulations between the
humerus, ulna, and radius: the humeroulnar, humeroradial, and
proximal radioulnar joints.
Humerus
Humerus
Lateral border
Medial
supracondylar
ridge
Lateral
supracondylar
ridge
Coronoid
fossa
Radial fossa
Lateral
epicondyle
Medial
epicondyle
Capitulum
Trochlea
Coronoid
process
Head of radius
Neck of radius
Capitulotrochlear
groove
Medial
supracondylar
ridge
Lateral
supracondylar
ridge
Olecranon fossa
Lateral
epicondyle
Medial
epicondyle
Ulnar
groove
Head of radius,
articular
circumference
Olecranon
Ulnar
tuberosity
Radial
tuberosity
Radius
Radius
Ulna
Ulna
B
Posterior view.
A
Anterior view.
Humerus
Humerus
Radial
tuberosity
Radius
Head of
radius
Medial
supracondylar
ridge
Capitulum
Medial
epicondyle
Olecranon
Ulna
C
Medial view.
326
Coronoid
process
Lateral
supracondylar
ridge
Humeroradial
joint
Radius
Lateral
epicondyle
Capitulum
Humeroulnar
joint
Olecranon
Trochlea
DLateral view.
Proximal
radioulnar joint
Head of
radius
Ulna
Clinical box 26.1
Humerus
Brachioradialis
Triceps brachii
Medial epicondyle
Lateral epicondyle
Capitulotrochlear
groove
Extensor carpi
radialis longus
Ulnar collateral lig.
Radial collateral lig.
Humeroulnar joint
(humeral trochlea
and trochlear notch)
Proximal radioulnar
joint (articular circumference and radial
notch of ulna)
Forearm flexors
Ulna
Supinator
Humeroradial joint
(capitulum of humerus
and articular fovea)
Anular lig.
of radius
Head of radius
Sacciform recess
Biceps brachii
tendon
Plane of
Plane of
section in b section in c
A C
oronal section viewed from the front (note the planes of
section shown in B and C).
Brachialis Humerus Triceps brachii
The fat pads between the fibrous capsule and synovial
membrane are part of the normal anatomy of the elbow
joint. The anterior pad is most readily seen on a sagittal
MRI while the posterior pad is often hidden within the
bony fossa (see Figs. 26.3 and 29.11). With an effusion
of the joint space, the inferior edge of the anterior pad
appears concave as it gets pushed superiorly by the
intra-articular fluid. This causes the pad to resemble
the shape of a ship’s sail, thus creating a characteristic
“sail sign.” The alignment of the prominences in the
elbow also aids in the identification of fractures and
dislocations.
26 Elbow & Forearm
Assessing elbow injuries
Fig. 26.3 Skeletal and soft-tissue elements of the right
elbow joint
A
Posterior view of extended elbow: The
­epicondyles and olecranon lie in a
straight line.
B
Medial view of flexed e
­ lbow: The
epicondyles and olecranon lie in
a straight line.
C
Posterior view of flexed elbow:
The two epicondyles and the tip of
the olecranon form an equilateral
triangle. Fractures and dislocations
alter the shape of the triangle.
Brachialis Humerus Triceps brachii
Fat pad
Capitulum
Coronoid
fossa
Olecranon
fossa
Olecranon
bursa
Trochlea
Fat pad
Brachioradialis
Articular
circumference
Articular
fovea
Head of
radius
Radial notch
of ulna
Olecranon
Trochlear
notch
Anconeus
Supinator
Radius
Ulna
B
Sagittal section through the humeroradial joint and
proximal radioulnar joint, medial view.
Coronoid process
Ulna
CSagittal section through the humeroulnar joint,
­medial view.
327
Ligaments of the Elbow Joint
Upper Limb
Fig. 26.4 Ligaments of the elbow joint
Right elbow in flexion.
Humerus
Lateral
supracondylar
ridge
Olecranon
fossa
Lateral
epicondyle
Medial
epicondyle
Radial
collateral lig.
Ulnar groove
Ulnar collateral lig.
Humerus
Olecranon
Radial
tuberosity
Radius
A
Posterior view.
Anular lig.
of radius
Ulnar collateral lig.
(anterior part)
Medial
epicondyle
Ulnar collateral lig.
(posterior part)
Humerus
Ulnar collateral lig.
(transverse part)
Lesser tubercle,
supracondylar
ridge
Ulna
Sacciform
recess
Radius
Table 26.1
C
Lateral view.
328
Radial collateral
lig.
Olecranon
B
Medial view.
Lateral
epicondyle
Olecranon
Coronoid
process
Anular lig.
of radius
Neck of
radius
Ulna
Joints and ligaments of the elbow
Joint
Articulating surfaces
Ligament
Humeroulnar
joint
Trochlea
Ulna (trochlear
notch)
Ulnar collateral
ligament
Humeroradial
joint
Capitulum
Radius (articular
fovea)
Radial collateral
ligament
Proximal
radioulnar joint
Radius (articular
circumference)
Ulna (radial
notch)
Anular
ligament
Fig. 26.5 Joint capsule of the elbow
Right elbow in extension, anterior view.
26 Elbow & Forearm
Humerus
Medial
epicondyle
Joint
capsule
Lateral
epicondyle
Radial
collateral lig.
Ulnar
collateral lig.
Anular lig.
of radius
Radial
tuberosity
Radius
Ulnar
tuberosity
Ulna
A
Intact joint capsule.
Clinical box 26.2
Humerus
Subluxation of the radial head (nursemaid’s elbow)
A common and painful injury of small children occurs when the arm is
jerked upward with the forearm pronated, tearing the anular ligament
from its loose attachment on the radial neck. As the immature radial head
slips out of the socket, the ligament may become trapped between the
radial head and the capitulum of the humerus. Supinating the forearm and
flexing the elbow usually returns the radial head to the normal position.
Radial fossa
Coronoid
fossa
Capitulotrochlear groove
Medial
epicondyle
Lateral
epicondyle
Capitulum
Trochlea
Radial
collateral lig.
Ulnar
collateral lig.
Head of radius
Humerus
Anular lig.
of radius
Coronoid
process
Sacciform
recess
Capitulum
Radial
head
Ulna
Epiphyseal
plates
Radius
Ulna
Anular lig.
B
Windowed joint capsule.
329
Upper Limb
Radioulnar Joints
The proximal and distal radioulnar joints function together to enable
pronation and supination movements of the hand. The joints are functionally linked by the interosseous membrane. The axis for pronation
and supination runs obliquely from the center of the humeral capitulum
through the center of the radial articular fovea down to the styloid
process of the ulna.
Fig. 26.6 Supination
Fig. 26.7 Pronation
Right forearm, anterior view.
Right forearm, anterior view.
Axis of pronation/
supination
Axis of
pronation/
supination
Radial
collateral lig.
Radial
collateral
lig.
Olecranon
Trochlear
notch
Coronoid
process
Articular
fovea
Ulnar
collateral
lig.
Anular
lig.
Ulnar
tuberosity
Radial
tuberosity
Anular lig.
Proximal radioulnar joint
Neck of
radius
Ulnar
tuberosity
Radial
tuberosity
Oblique cord
Anterior
border
Shaft of ulna
Interosseous
border
of ulna
Interosseous
border
of ulna
Interosseous
border
of radius
Interosseous
border
Interosseous
membrane
Interosseous
membrane
Lateral
surface
Posterior
border
Posterior
surface
Styloid process
of radius
330
Head of ulna
Dorsal
radioulnar lig.
Palmar
radioulnar lig.
Head of ulna
Styloid process
of ulna
Styloid process
of ulna
Dorsal
tubercle
Distal
radioulnar joint
Radius
Fig. 26.9 Distal radioulnar joint rotation
Right elbow, proximal (superior) view.
Right forearm, distal view of articular surfaces of radius and ulna. The
dorsal and palmar radioulnar ligaments stabilize the distal radioulnar joint.
Olecranon
Head of radius, Articular
lunula
fovea
Radius, carpal
articular surface
Distal radioulnar
joint
Trochlear
notch
Palmar
radioulnar lig.
26 Elbow & Forearm
Fig. 26.8 Proximal radioulnar joint
Head of ulna
Anular
lig.
Proximal radioulnar Coronoid
joint
process
Dorsal radioulnar
lig.
Styloid
process
of radius
A
Proximal articular surfaces of radius
and ulna.
Dorsal
tubercle
Extensor
carpi ulnaris
tendon
Styloid process
of ulna
A
Supination.
Styloid process
of radius
Olecranon
Trochlear
notch
Ulnar
notch
Anular
lig.
Radial notch
of ulna
Articular
circumference
Coronoid
process
B Radius removed.
Styloid process
of ulna
B
Semipronation.
Clinical box 26.3
Radius fracture
Dorsal radioulnar
lig.
Falls onto the outstretched arm often result in fractures of the distal
radius. In a Colles’ fracture, the distal fragment is tilted dorsally.
Head of ulna
Dorsal
A
B
Styloid process of
radius
Styloid process
of ulna
Palmar
radioulnar lig.
C
Pronation.
331
Upper Limb
Muscles of the Forearm: Anterior Compartment
Fig. 26.10 Anterior muscles of the forearm: Dissection
Right forearm, anterior view. Muscle origins are shown in red,
insertions in blue.
Biceps brachii
Triceps brachii
Brachialis
Brachialis
Medial epicondyle,
common head
of flexors
Biceps brachii
tendon
Medial epicondyle,
common head
of flexors
Bicipital
aponeurosis
Brachioradialis
Biceps brachii
Extensor carpi
radialis longus
Pronator
teres
Extensor carpi
radialis brevis
Flexor
carpi radialis
Pronator
teres
Supinator
Palmaris
longus
Flexor
carpi ulnaris
Flexor digitorum
superficialis
Flexor digitorum
superficialis
Flexor
pollicis longus
Flexor
pollicis longus
Abductor
pollicis longus
Pronator
quadratus
Brachioradialis
Palmaris
longus
Abductor
pollicis
longus
Flexor digitorum
superficialis
tendons
Flexor digitorum
superficialis
tendons
Flexor pollicis
longus tendon
Flexor pollicis
longus tendon
Flexor digitorum
profundus tendons
A
Superficial flexors and radialis muscles.
332
Flexor
carpi ulnaris
Flexor digitorum
profundus
tendons
B
Removed: Radialis muscles (brachioradialis, extensor carpi radialis longus, and extensor carpi radialis brevis), flexor carpi radialis, flexor carpi
ulnaris, abductor pollicis longus, palmaris longus, and biceps brachii.
Pronator teres,
humeral head
Medial epicondyle,
common head
of flexors
Biceps brachii
Flexor digitorum
superficialis,
ulnar head
Brachioradialis
Brachialis
Extensor carpi
radialis longus
Pronator teres,
humeral head
Extensor carpi
radialis brevis
Medial epicondyle,
common
head of flexors
Lateral epicondyle,
common head of
extensors, supinator
Biceps brachii
Supinator
Supinator
Flexor digitorum
superficialis,
radial head
Flexor digitorum
superficialis,
radial head
Pronator
teres
Flexor digitorum
profundus
Pronator
teres
26 Elbow & Forearm
Brachialis
Flexor digitorum
superficialis,
ulnar head
Pronator teres,
ulnar head
Brachialis
Flexor digitorum
profundus
Flexor
pollicis longus
Flexor
pollicis longus
Pronator
quadratus
Pronator
quadratus
Brachioradialis
Abductor
pollicis longus
Flexor
pollicis longus
Flexor pollicis
longus tendon
Flexor digitorum
profundus
tendons
C
Removed: Pronator teres and flexor digitorum superficialis.
Flexor
carpi ulnaris
Flexor
carpi radialis
Flexor digitorum
superficialis
Flexor digitorum
profundus
DRemoved: Brachialis, supinator, pronator quadratus, and deep flexors.
333
Upper Limb
Muscles of the Forearm: Posterior Compartment
Fig. 26.11 Posterior muscles of the forearm: Dissection
Right forearm, posterior view. Muscle origins are shown in red,
insertions in blue.
Brachioradialis
Brachioradialis
Triceps brachii
Triceps brachii
Medial
epicondyle,
common
head of flexors
Olecranon
Extensor carpi
radialis brevis
Anconeus
Extensor carpi
radialis longus
Anconeus
Extensor carpi
radialis brevis
Extensor
digitorum
Flexor
digitorum
profundus
Supinator
Flexor
carpi ulnaris
Extensor
carpi ulnaris
Flexor
carpi ulnaris
Abductor
pollicis longus
Extensor carpi
radialis brevis
Extensor
digiti minimi
Extensor
pollicis longus
Abductor
pollicis longus
Brachioradialis
Brachioradialis
Extensor
pollicis brevis
Extensor carpi
radialis longus
Extensor
pollicis brevis
Extensor
carpi ulnaris
Extensor
indicis
Dorsal (“Lister’s”)
tubercle of radius
Intertendinous
connections
Extensor
digitorum
tendons,
dorsal digital
expansion
A
Superficial extensors and radialis group.
334
Extensor
pollicis
longus
tendon
Extensor carpi
radialis brevis
tendon
Extensor
digiti
minimi
Extensor carpi
radialis longus
tendon
Extensor
digitorum
B
Removed: Triceps brachii, anconeus, flexor carpi ulnaris, extensor
carpi ulnaris, and extensor digitorum.
Brachioradialis
Extensor carpi
radialis longus
Extensor carpi
radialis longus
Extensor carpi
radialis brevis
Lateral epicondyle,
common head of
extensors
Triceps brachii
Medial
epicondyle,
common head
of flexors
Anconeus
Flexor
digitorum
profundus
Supinator
Flexor
digitorum
profundus
Extensor carpi
radialis brevis
26 Elbow & Forearm
Brachioradialis
Supinator,
humeral head
Lateral epicondyle,
common head
of extensors
Supinator
Flexor
carpi ulnaris
Pronator teres
Pronator teres
Abductor
pollicis longus
Abductor
pollicis longus
Extensor
pollicis longus
Extensor
pollicis longus
Extensor
pollicis brevis
Extensor
pollicis brevis
Extensor
indicis
Extensor
indicis
Extensor
carpi ulnaris
Brachioradialis
Interosseous
membrane
Brachioradialis
Dorsal (“Lister’s”)
tubercle
Abductor
pollicis longus
Abductor
pollicis longus
Extensor carpi
radialis brevis
Extensor carpi
radialis longus
Extensor carpi
radialis brevis
Extensor carpi
radialis longus
Extensor
pollicis brevis
Extensor
pollicis longus
Extensor
pollicis longus
Extensor
digiti
minimi
Extensor
digitorum
Extensor
indicis
C
Removed: Abductor pollicis longus, extensor pollicis longus, and
radialis muscles.
DRemoved: Flexor digitorum profundus, supinator, extensor pollicis
brevis, and extensor indicis.
335
Upper Limb
Muscle Facts (I)
Fig. 26.12 Anterior compartment
of the forearm
Right forearm, anterior view.
Humeral-ulnar
head
①
Radial head
②
③
④
⑥
⑤
⑦
⑧
A
Superficial.
Table 26.2
B
Intermediate.
C
Deep.
Anterior compartment of the forearm
Muscle
Origin
Insertion
Humeral head: medial epicondyle
of humerus
Ulnar head: coronoid process
Lateral radius (distal to
supinator insertion)
Innervation
Action
Superficial muscles
① Pronator teres
② Flexor carpi radialis
Medial epicondyle of humerus
Median n. (C6, C7)
Wrist: flexion and abduction
(radial deviation) of hand
Palmar aponeurosis
Median n. (C7, C8)
Elbow: weak flexion
Wrist: flexion tightens palmar
aponeurosis
Humeral head: medial epicondyle
Ulnar head: olecranon
Pisiform; hook of hamate;
base of 5th metacarpal
Ulnar n. (C7–T1)
Wrist: flexion and adduction (ulnar
deviation) of hand
Humeral-ulnar head: medial
epicondyle of humerus and
coronoid process of ulna
Radial head: upper half of anterior
border of radius
Sides of middle phalanges of
2nd to 5th digits
Median n. (C8, T1)
Elbow: weak flexion
Wrist, MCP, and PIP joints of 2nd
to 5th digits: flexion
Ulna (proximal two thirds of
flexor surface) and interosseous
membrane
Distal phalanges of 2nd to
5th digits (palmar surface)
Median n. (C8, T1, radial
half of fingers 2 and 3)
Ulnar n. (C8, T1, ulnar
half of fingers 4 and 5)
Wrist, MCP, PIP, and DIP joints of
2nd to 5th digits: flexion
③ Palmaris longus
④ Flexor carpi ulnaris
Base of 2nd metacarpal
(variance: base of 3rd
metacarpal)
Elbow: weak flexion
Forearm: pronation
Intermediate muscles
⑤ Flexor digitorum superficialis
Deep muscles
⑥ Flexor digitorum profundus
⑦ Flexor pollicis longus
⑧ Pronator quadratus
Radius (midanterior surface) and
adjacent interosseous membrane
Distal phalanx of thumb
(palmar surface)
Distal quarter of ulna (anterior
surface)
Distal quarter of radius
(anterior surface)
Median n. (C8, T1)
DIP, distal interphalangeal; IP, interphalangeal; MCP, metacarpophalangeal; PIP, proximal interphalangeal.
336
Wrist: flexion and abduction (radial
deviation) of hand
Carpometacarpal joint of thumb:
flexion
MCP and IP joints of thumb: flexion
Hand: pronation
Distal radioulnar joint: stabilization
Right forearm, anterior view.
Medial
epicondyle
Medial
epicondyle,
common
head of
flexors
Radial
tuberosity
Pronator
teres
Flexor
carpi
radialis
Palmaris
longus
Flexor
carpi
ulnaris
Coronoid
process
Interosseous
membrane
Flexor
digitorum
superficialis,
radial head
Radial
tuberosity
Flexor digitorum
superficialis,
humeral-ulnar
head
26 Elbow & Forearm
Fig. 26.13 Anterior compartment of the forearm
Ulnar
tuberosity
Interosseous
membrane
Radius
Flexor
digitorum
profundus
Flexor pollicis
longus
Flexor
digitorum
superficialis
Base of 2nd
metacarpal
Pronator
quadratus
Tubercle of
trapezium
Trapezium
Pisiform bone
Hook of
hamate
Base of 5th
metacarpal
Palmar
aponeurosis
2nd
through
5th middle
phalanges
A
Superficial muscles.
Pisiform
bone
Hook of
hamate
Base of 1st
distal phalanx
4th distal
phalanx
B
Intermediate muscles.
C
Deep muscles.
337
Upper Limb
Muscle Facts (II)
Fig. 26.14 Posterior compartment
of the forearm: Radialis muscles
Right forearm, posterior view, schematic.
Clinical box 26.4
Lateral epicondylitis
Lateral epicondylitis, or tennis elbow, involves the extensor muscles and
tendons of the forearm that attach on the lateral epicondyle. The tendon
most commonly involved is that of the extensor carpi radialis brevis, a
muscle that helps stabilize the wrist when the elbow is extended. When
the extensor carpi radialis brevis is weakened from overuse, microscopic
tears form in the tendon where it attaches to the lateral epicondyle.
This leads to inflammation and pain. There is some evidence that the
inflammation can extend back along the tendon to the periosteum of the
lateral epicondyle.
A
S
D
Athletes are not the only people who get tennis elbow and are actually
in the minority — leading some to suggest the condition be referred to
as “lateral elbow syndrome”. Workers whose activities require repetitive
and vigorous use of the forearm muscles, such as common to painters,
plumbers, and carpenters, are particularly prone to developing this
pathology. Studies show a high incidence also among auto workers,
cooks, and butchers. Common signs and symptoms of tennis elbow
include pain with wrist extension against resistance, point tenderness or
burning on the lateral epicondyle, and weak grip strength. Symptoms are
intensified with forearm activity.
Table 26.3
338
Posterior compartment of the forearm: Radialis muscles
Muscle
Origin
Insertion
Innervation
Action
① Brachioradialis
Distal humerus (lateral surface), lateral
intermuscular septum
Styloid process of the radius
Radial n. (C5, C6)
Elbow: flexion
Forearm: semipronation
② Extensor carpi radialis longus
Lateral supracondylar ridge of distal
humerus, lateral intermuscular septum
2nd metacarpal (base)
Radial n. (C6, C7)
③ Extensor carpi radialis brevis
Lateral epicondyle of humerus
3rd metacarpal (base)
Radial n. (C7, C8)
Elbow: weak flexion
Wrist: extension and abduction
Fig. 26.15 Posterior compartment of the forearm:
Radialis muscles
Right forearm.
Brachioradialis
Humerus
Lateral supracondylar crest
Lateral
epicondyle
Medial
epicondyle
Lateral
epicondyle
26 Elbow & Forearm
Humerus
Olecranon
Olecranon
Extensor carpi
radialis longus
Brachioradialis
Ulna
Extensor carpi
radialis brevis
Extensor carpi
radialis longus
Ulna
Extensor carpi
radialis brevis
Radius
Interosseous
membrane
Radius
Brachioradialis
tendon
Styloid process
of radius
Styloid process
of radius
Base of 3rd
metacarpal
3rd
metacarpal
A
Lateral (radial) view.
Base of 3rd
metacarpal
Base of 2nd
metacarpal
Base of 2nd
metacarpal
2nd
metacarpal
Shaft of
2nd
metacarpal
B
Posterior view.
339
Upper Limb
Muscle Facts (III)
Fig. 26.16 Posterior compartment
of the forearm
Right forearm, posterior view.
④
⑤
③
②
①
⑥
⑦
⑧
A Superficial muscles.
Table 26.4
B Deep muscles.
Posterior compartment of the forearm
Muscle
Origin
Insertion
Innervation
Action
Superficial muscles
① Extensor digitorum
Common head (lateral epicondyle
of humerus)
② Extensor digiti minimi
Wrist: extension
MCP, PIP, and DIP joints of 2nd to 5th digits:
extension/abduction of fingers
Dorsal digital expansion of 2nd
to 5th digits
Dorsal digital expansion of 5th
digit
Radial n.
(C7, C8)
Wrist: extension, ulnar abduction of hand
MCP, PIP, and DIP joints of 5th digit: extension
and abduction of 5th digit
Common head (lateral epicondyle
of humerus)
Ulnar head (dorsal surface)
Base of 5th metacarpal
④ Supinator
Olecranon, lateral epicondyle of
humerus, radial collateral ligament,
annular ligament of radius
Radius (between radial tuberosity
and insertion of pronator teres)
⑤ Abductor pollicis longus
Radius and ulna (dorsal surfaces,
interosseous membrane)
Base of 1st metacarpal
Radiocarpal joint: abduction of the hand
Carpometacarpal joint of thumb: abduction
⑥ Extensor pollicis brevis
Radius (posterior surface) and
interosseous membrane
Base of proximal phalanx of
thumb
Radiocarpal joint: abduction (radial deviation)
of hand
Carpometacarpal and MCP joints of thumb:
extension
③ Extensor carpi ulnaris
Wrist: extension, adduction (ulnar deviation)
of hand
Deep muscles
Radial n.
(C6, C7)
Radial n.
(C7, C8)
⑦ Extensor pollicis longus
Ulna (posterior surface) and
interosseous membrane
Base of distal phalanx of thumb
Wrist: extension and abduction (radial
deviation) of hand
Carpometacarpal joint of thumb: adduction
MCP and IP joints of thumb: extension
⑧ Extensor indicis
Ulna (posterior surface) and
interosseous membrane
Posterior digital extension of
2nd digit
Wrist: extension
MCP, PIP, and DIP joints of 2nd digit: extension
DIP, distal interphalangeal; IP, interphalangeal; MCP, metacarpophalangeal; PIP, proximal interphalangeal.
340
Radioulnar joints: supination
Fig. 26.17 Posterior compartment of the forearm:
Superficial and deep muscles
Right forearm, posterior view.
Olecranon
Common head of
extensor digitorum,
extensor digiti
minimi, and extensor
carpi ulnaris
Medial
epicondyle
Lateral
epicondyle
Ulnar
groove
Olecranon
26 Elbow & Forearm
Lateral
epicondyle
Supinator
Ulna
Ulna
Extensor carpi
ulnaris
Posterior
border
of ulna
Extensor
digitorum
Radius
Abductor
pollicis longus
Extensor digiti
minimi
Extensor
pollicis longus
Extensor
pollicis brevis
Radius
Extensor
indicis
Dorsal
tubercle
Base of 1st
metacarpal
Base of 5th
metacarpal
5th proximal
phalanx,
base
Dorsal
digital
expansion,
intertendinous connections
A
Superficial extensors.
2nd
metacarpal
1st metacarpal
1st
proximal
phalanx,
base
1st distal
phalanx,
base
B
Deep extensors with supinator.
341
27
Wrist & Hand
Bones of the Wrist & Hand
Upper Limb
Fig. 27.1 Dorsal view
Right hand.
Phalanges
2nd distal phalanx
2nd middle phalanx
Metacarpals
2nd proximal phalanx
Carpal
bones
Table 27.1
Bones of the wrist
and hand
1st to 5th proximal phalanges
Phalanges
2nd to 5th middle phalanges*
1st to 5th distal phalanges
Metacarpal
bones
Carpal bones
1st to 5th metacarpals
Trapezium
Scaphoid
Trapezoid
Lunate
Capitate
Triquetrum
Hamate
Pisiform
*There are only four middle phalanges (the
thumb has only a proximal and a distal phalanx).
1st metacarpal
Capitate
Trapezoid
Hamate
Triquetrum
Trapezium
Scaphoid
Lunate
Styloid process
of radius
Radius
342
Styloid process
of ulna
Ulna
Fig. 27.3 Radiograph of the wrist
27 Wrist & Hand
Anteroposterior view of left limb.
Fig. 27.2 Palmar view
Right hand.
Tuberosity of
distal phalanx
Trapezoid
Head
Shaft
Hook of
hamate
Trapezium
Middle
phalanx
Capitate
Pisiform
Scaphoid
Triquetrum
Base
Lunate
Clinical box 27.1
Scaphoid Fractures
Head
Sesamoid
bones
Metacarpal
Shaft
Scaphoid fractures are the most common
carpal bone fractures, generally occurring at
the narrowed waist between the proximal
and distal poles (A, right scaphoid red line;
B, white arrow). Because blood supply
to the scaphoid is transmitted via the
distal segment, fractures at the waist can
compromise the supply to the proximal
segment, often resulting in nonunion and
avascular necrosis.
Base
Tubercle of
trapezium
Pisiform
Triquetrum
Capitate
Lunate
Ulna
Distal
Trapezoid
Hook of
hamate
Tubercle of
scaphoid
Styloid
process
Styloid process
of radius
Head
A
Proximal
Radius
B
343
Upper Limb
Carpal Bones
Fig. 27.4 Carpal bones of the right wrist
1st to 5th
metacarpals
Capitate
Hamate
Triquetrum
Scaphoid
Lunate
Styloid process
of ulna
Trapezoid
Trapezium
Styloid process of radius
Dorsal
tubercle
Radius
Ulna
A
Carpal bones of the right wrist with the wrist
in flexion, proximal view.
Tubercle of trapezium
B
Carpal and metacarpal bones of the right wrist
with radius and ulna removed, proximal view.
344
Carpal tunnel
Pisiform
27 Wrist & Hand
Scaphoid
Lunate
Triquetrum
Pisiform
Tubercle of
scaphoid
Articular disk
(ulnocarpal disk)
Styloid process
of radius
C
Articular surfaces of the radiocarpal joint of
the right wrist. The proximal row of carpal
bones is shown from the proximal view.
The articular surfaces of the radius and
ulna, and the articular disk (ulnocarpal
disk) are shown from the distal view.
Styloid process
of ulna
Dorsal
tubercle
Radius, carpal
articular surface
Articular
capsule
Ulnar collateral
ligament of wrist joint
1st to 5th
metacarpals
Capitate
Hamate
Distal row of
carpal bones
Trapezoid
Hook of
hamate
Trapezium
Pisiform
Tubercle of
trapezium
Proximal row of
carpal bones
Tubercle of
scaphoid
DArticular surfaces of the midcarpal joint of the
right wrist. The distal row of carpal bones is
shown from the proximal view. The proximal
row is shown from the distal view.
Scaphoid
Lunate
Triquetrum
345
Upper Limb
Joints of the Wrist & Hand
Fig. 27.5 Joints of
the wrist and hand
Clinical box 27.2
Abduction and adduction at the
metacarpophalangeal joint
Distal interphalangeal
joint
Proximal
interphalangeal
joint
Interphalangeal
joint of
thumb
Abduction and adduction movements are described
in relation to the middle finger: all movements away
from the middle finger are classified as abduction, all
movements toward the middle finger as adduction.
Adduction
Abduction
Metacarpophalangeal
joint
Metacarpophalangeal
joint of
thumb
Carpometacarpal
joints
Midcarpal
joint
Carpometacarpal
joint of thumb
Radiocarpal
joint
Distal
phalanx
Distal
radioulnar
joint
Middle
phalanx
Distal interphalangeal
joint
Proximal
interphalangeal
joint
Proximal
phalanx
A Right hand, posterior (dorsal) view.
Metacarpophalangeal
joint
Collateral ligaments
Interphalangeal joint
1st dorsal
interosseous
Metacarpophalangeal
joint
4th dorsal interosseous
5th metacarpal
Abductor digiti minimi
1st metacarpal
Opponens pollicis
Trapezoid
Carpometacarpal
joint of the thumb
Trapezium
Radial collateral lig.
of wrist joint
Scaphoid
Midcarpal joint
Radiocarpal joint
B
Coronal section. Right hand,
posterior (dorsal) view.
346
Carpometacarpal joint
Hamate
Capitate
Pisiform
Triquetrum
Ulnar collateral lig. of
wrist joint
Articular disk (ulnocarpal)
Lunate
Distal radioulnar
joint
Interosseous
membrane
Fig. 27.6 Carpometacarpal joint of the thumb
Fig. 27.7 Movements of the carpometacarpal
joint of the thumb
Right hand, radial view. The 1st metacarpal bone has
been moved slightly distally to expose the articular surface of the trapezium. Two cardinal axes of motion are
shown here: (a) abduction/adduction and (b) flexion/
extension.
Distal
phalanx
Head
Shaft
Trapezium
Middle
phalanx
Base
27 Wrist & Hand
Abduction/
adduction axis
Tuberosity of
distal phalanx
Phalanx
Right hand, Palmar view.
Flexion/
extension axis
A The neutral (0°) position.
B
Axes of motion in the carpometacarpal joint of the thumb.
Proximal
phalanx
1st
distal
phalanx
1st
proximal
phalanx
Head
Shaft
1st
metacarpal
Metacarpal
C Adduction.
D Abduction.
E Flexion.
F Extension.
Base
a
Trapezium
Trapezoid
Capitate
b
Styloid process
of radius
Lunate
Scaphoid
Styloid process
of ulna
Radius
Ulna
G Opposition.
347
Upper Limb
Ligaments of the Hand
Fig. 27.8 Ligaments of the hand
Right hand.
Distal interphalangeal
joint (collateral ligs.)
Proximal
interphalangeal
joint (collateral ligs.)
Metacarpophalangeal
joint (collateral ligs.)
Dorsal
metacarpal ligs.
Dorsal carpometacarpal
ligs.
Dorsal
intercarpal
ligs.
Ulnar collateral
lig. of wrist joint
Radial collateral
lig. of wrist joint
Dorsal
radiocarpal
lig.
Dorsal
radioulnar
lig.
A
Posterior (dorsal) view.
Clinical box 27.3
40–60°
Movements at the radiocarpal and
midcarpal joints
Radial deviation
Ulnar deviation
0°
30–40°
20°
Transverse
axis
Palmar flexion and dorsal extension occur
around a transverse axis (A) that runs
through the lunate bone (radiocarpal joint)
and capitate bone (midcarpal joint). Radial
and ulnar deviation (B) occur around a
dorsopalmar axis that runs through the
capitate bone.
0°
A
348
Dorsal extension
60–80°
Palmar flexion
B
Dorsopalmar axis
27 Wrist & Hand
Distal
interphalangeal
joint capsule
Palmar ligs.
Proximal
interphalangeal
joint capsule
Deep
transverse
metacarpal ligs.
Metacarpophalangeal
joint capsule
Palmar
metacarpal ligs.
Palmar
carpometacarpal ligs.
Palmar
intercarpal ligs.
Flexor carpi
ulnaris tendon
Radial collateral
lig. of wrist joint
Palmar
ulnocarpal lig.
Palmar
radiocarpal lig.
Palmar
radioulnar lig.
BAnterior (palmar) view.
Cut: Flexor retinaculum.
Clinical box 27.4
Functional position of the hand
The anatomic position of the hand, in which the palm is flat, the fingers
are extended, and the forearm is supinated (palm facing forward), differs
from the normal relaxed position of the hand. At rest, the forearm is in
mid-supination/pronation (palm facing the body), the wrist is slightly
extended, the fingers form an arcade of flexion, and the thumb is in the
neutral position. Postoperative immobilization of the hand (by a cast or
splint) fixes the fingers in flexion and the wrist in extension to prevent
shortening of the ligaments and to maintain the ability of the hand to
assume normal resting position.
30°
10°
50–60°
30°
349
Ligaments & Compartments of the Wrist
Upper Limb
Fig. 27.9 Ligaments and bony boundaries of the carpal
tunnel
Right hand, anterior (palmar) view.
Hook of
hamate
Flexor retinaculum
(transverse carpal lig.)
Pisiform
bone
Tubercle of
trapezium
Carpal
tunnel
entrance
Capitate
Trapezoid
Radius
Ulna
Ulnar
carpal
eminence
A
Carpal tunnel and flexor retinaculum.
Carpometacarpal joint
of the thumb
Hook of
hamate
Pisiform
Flexor retinaculum
(transverse carpal lig.)
Triquetrum
Tubercle of trapezium
Lunate
Tubercle of scaphoid
Radial
carpal
eminence
B
Bony boundaries of the carpal tunnel.
Fig. 27.10 Carpal tunnel
Right hand, transverse section. The contents of the carpal and ulnar tunnels
are discussed on p. 391.
Ulnar tunnel
B
A
Palmar
carpal lig.
Hook of
hamate
Flexor retinaculum (transverse carpal lig.)
Passage for
flexor carpi
radialis tendon
Pisiform
Scaphoid
Triquetrum
Hamate
Capitate
A
Proximal part of the carpal tunnel.
Tubercle of
trapezium
Passage
for
flexor
carpi
radialis
tendon
Carpal tunnel
Carpal tunnel
350
Flexor
retinaculum
Hamate
Trapezium
Capitate
Trapezoid
Distal part of the carpal tunnel.
B
Fig. 27.11 Ulnocarpal complex
Metacarpals
Hamate
Ulnar collateral
lig. of wrist joint
Midcarpal
joint
Hamate
Trapezoid
Capitate
Lunate
Scaphoid
Radiotriquetral lig.
Triquetrum
Ulnar collateral
lig. of wrist joint
Ulnocarpal
meniscus
homologue
Radius
Triquetrum
Interosseous
membrane
Ulnocarpal
meniscus
homologue
Ulnocarpal disk
Styloid process
of ulna
Dorsal
radioulnar
lig.
Ulna
Extensor carpi
ulnaris muscle
tendon sheath
Radiocarpal joint
Distal
radioulnar joint
Styloid process
of ulna
Radius
Ulnotriquetral lig.
Ulnolunate lig.
Dorsal
tubercle
Lunate
27 Wrist & Hand
Right hand. The ulnocarpal complex (triangular fibrocartilage complex) consists of ligaments and disks that connect the distal ulna,
distal radioulnar joint, and the proximal carpal row.
B
Schematic of a section through the triangular fibrocartilage
(ulnocarpal) complex.
Radius carpal
articular surface
Ulnolunate
lig.
Ulnotriquetral
lig.
A
Right wrist, posterior (dorsal) view.
Palmar
radioulnar lig.
Ulnocarpal disk
(triangular disk)
Radius
Ulnar carpal
collateral lig.
Ulnocarpal
meniscus
homologue
Fig. 27.12 Compartments of the wrist
Dorsal
tubercle
Right wrist, posterior view, schematic. Interosseous
ligaments and the ulnocarpal disk divide the interarticular space into compartments.
Radiotriquetral
lig.
Dorsal
radioulnar lig.
Styloid process
of ulna
C
Right wrist, distal view.
Interosseous
ligs.
Radial
collateral
lig.
Pisiform
Distal radioulnar
joint
Thumb saddle joint
Ulnar collateral
lig.
Radiocarpal
joint
Carpometacarpal
compartment
Ulnocarpal meniscus
homologue
Medial carpal
compartment
Intermetacarpal
joint
Ulnocarpal disk
351
Upper Limb
Ligaments of the Fingers
Fig. 27.13 Ligaments of the fingers: Lateral view
Right middle finger. Joint capsules, ligaments, and digital tendon
sheaths. The outer fibrous layer of the tendon sheaths (stratum fibrosum) is strengthened by the anular and cruciform ligaments, which
Cruciform
lig. (C3)
Phalangoglenoid
lig.
Collateral
ligs.
also bind the sheaths to the palmar surface of the phalanx and prevent
palmar deviation of the sheaths during flexion.
Cruciform
lig. (C1)
Phalangoglenoid
lig.
Collateral
lig.
Collateral
ligs.
Accessory
collateral lig.
3rd
metacarpal
Anular ligs.
(A1–A5)
Deep transverse
metacarpal lig.
Flexor digitorum
profundus
tendon
Flexor
digitorum
superficialis
tendon
Flexor
digitorum
superficialis
tendon
Flexor
digitorum
profundus
tendon
Fig. 27.14 Ligaments during extension and flexion of fingers: Lateral view
Proximal
interphalangeal
joint
Distal interphalangeal
joint
A5 C3
A4
C2
A3
Metacarpophalangeal joint
C1
A2
A
Extension. Note: Whereas the 1st through 5th anular ligaments
(A1–A5) have fixed positions, the cruciform ligaments (C1–C3) are
highly variable in their course.
A1
Phalangoglenoid
lig.
Collateral
lig.
Proximal
phalanx
Metacarpal
bone
A2
A1
B
Flexion.
352
Accessory
collateral
lig.
C
Extension of the metacarpophalangeal
joint. Note: The collateral ligament is lax.
DFlexion of the metacarpophalangeal joint. Note: The
collateral ligament is taut.
Fig. 27.15 Ligaments of the fingers: Anterior (palmar)
view
Right middle finger.
Flexor
digitorum
profundus
tendon
Fig. 27.16 Third metacarpal: Transverse section
Proximal view.
Cruciform lig. (C3)
Extensor
digitorum tendon
Middle phalanx
27 Wrist & Hand
Distal interphalangeal
joints (collateral ligs.)
Dorsal
Proximal interphalangeal
joints
(collateral ligs.)
3rd metacarpal
bone
Flexor
digitorum
superficialis
tendon
Anular
ligs.
(A1–A5)
Collateral lig.
Cruciform lig. (C1)
Deep
transverse
metacarpal
lig.
Palmar lig.
Proximal
phalanx
Deep transverse
metacarpal lig.
Plane of
section in
Fig. 27.16
Flexor
digitorum
profundus tendon
Metacarpophalangeal
joint (collateral ligs.)
Metacarpal
bone
Flexor
digitorum
superficialis
tendon
Anular lig.
(A1)
Flexor
digitorum
superficialis
tendon
Flexor digitorum
profundus tendon
A
Superficial ligaments.
B
Deep ligaments with digital
tendon sheath removed.
Fig. 27.17 Fingertip: Longitudinal section
The palmar articular surfaces of the phalanges are enlarged proximally
at the joints by the palmar ligament. This fibrocartilaginous plate, also
known as the volar plate, forms the floor of the digital tendon sheaths.
Nail
Tuberosity
of distal
phalanx
Distal
phalanx
Distal interphalangeal
joint
Extensor digitorum
tendon (dorsal
digital expansion)
Middle phalanx
Palmar lig.
Flexor digitorum
profundus tendon
353
Upper Limb
Muscles of the Hand: Superficial & Middle Layers
Fig. 27.18 Intrinsic muscles of the hand:
Superficial and middle layers
Clinical box 27.5
Right hand, palmar surface.
Dupuytren’s contracture
Cruciform ligs.
Anular ligs. (A1–A5)
Deep
transverse
metacarpal lig.
Superficial
transverse
metacarpal lig.
Transverse fascicles
Gradual atrophy of the palmar aponeurosis
leads to progressive shortening of the palmar
fascia, chiefly affecting the 4th and 5th digits.
Over a period of years, the contracture may
become so severe that the fingers assume a
flexed position (with fingertips touching the
palms), severely compromising the grasping
ability of the hand. The causes of Dupuytren’s
contracture are poorly understood, but it is a
relatively common condition, most prevalent
in men over 40 and associated with chronic
liver disease (i.e., cirrhosis). Treatment
generally consists of complete surgical
removal of the palmar aponeurosis.
Adductor pollicis
Longitudinal
fascicles
Abductor digiti
minimi
Flexor pollicis
brevis
Flexor digiti
minimi brevis
Abductor
pollicis brevis
Palmaris brevis
Palmar
aponeurosis
Flexor
carpi ulnaris
Opponens
pollicis
Flexor
retinaculum*
Antebrachial
fascia
Flexor
pollicis
longus
tendon
Palmaris
longus
tendon
A
Palmar aponeurosis.
*Also known as transverse carpal ligament.
Flexor digitorum
superficialis tendons
Common flexor
tendon sheath
B
Carpal and digital tendon
sheaths. Removed: Palmar
aponeurosis, palmaris
longus, antebrachial fascia,
and palmaris brevis.
354
Flexor digitorum
profundus
tendons
Flexor retinaculum
Pronator quadratus
Flexor digitorum
superficialis
Flexor pollicis longus
Flexor carpi radialis
Clinical box 27.6
The digital tendon sheath of the thumb is
continuous with the carpal tendon sheath
of the flexor pollicis longus. The remaining
fingers show variable communication with the
carpal tendon sheaths (A is the most common
variation). Infections within the tendon
sheaths from puncture wounds of the fingers
can track proximally to communicating spaces
of the hand.
Deep
transverse
metacarpal lig.
1st dorsal
interosseus
Adductor pollicis
(transverse head)
Lumbricals
Adductor pollicis
(oblique head)
Flexor pollicis
brevis (superficial head)
Opponens
digiti minimi
Flexor
digiti minimi
brevis
Abductor
digiti minimi
27 Wrist & Hand
Tendon sheath communication
A
B
C
Abductor
pollicis brevis
Opponens pollicis
Flexor
retinaculum
Flexor digitorum
profundus tendons
Abductor
pollicis
longus
Flexor pollicis
longus tendon
C
Superficial layer of muscles.
Removed: Tendon sheaths.
Flexor digitorum
superficialis
tendons
Flexor digitorum
profundus tendons
Flexor pollicis
brevis (superficial head)
Abductor
digiti
minimi
Lumbricals
Abductor pollicis
brevis
Opponens pollicis
Flexor digiti minimi
brevis
Flexor carpi
ulnaris tendon
Flexor pollicis brevis
(superficial head)
Flexor retinaculum
Abductor pollicis
longus tendon
DMiddle layer of muscles.
Removed: Flexor digitorum
superficialis, flexors carpi
radialis and ulnaris, and
pronator quadratus.
Flexor digitorum
profundus
Extensor pollicis brevis
Flexor carpi radialis
tendon
Flexor pollicis longus
355
Upper Limb
Muscles of the Hand: Middle & Deep Layers
Fig. 27.19 Intrinsic muscles of the hand:
Middle and deep layers
Right hand, palmar surface.
Flexor digitorum
profundus tendons
Flexor pollicis
longus tendon
Flexor
digitorum
superficialis
tendons
Adductor pollicis
(transverse head)
Adductor pollicis
(oblique head)
Lumbricals
Flexor pollicis brevis
(superficial head)
Abductor
digiti minimi
Abductor pollicis
brevis
Flexor digiti
minimi brevis
2nd and 3rd
palmar interossei
Opponens
pollicis
Opponens digiti minimi
Flexor digiti minimi brevis
Abductor digiti minimi
Flexor
retinaculum
Palmar ligs.
A
Middle layer of muscles. Cut: Flexor digitorum
profundus, lumbricals, flexor pollicis longus,
and flexor digiti minimi brevis.
Adductor pollicis
1st through
4th dorsal
interossei
Flexor pollicis brevis
(superficial head)
Flexor pollicis brevis
(deep head)
Opponens digiti minimi
1st through 3rd
palmar interossei
Opponens pollicis
Flexor carpi
ulnaris tendon
Abductor pollicis
longus tendon
Extensor pollicis brevis
B
Deep layer of muscles. Cut: Opponens digiti
minimi, opponens pollicis, flexor pollicis
brevis, and adductor pollicis (transverse
and oblique heads).
356
Flexor carpi
radialis tendon
Fig. 27.20 Origins and insertions
of muscles of the hand
Extensor
digiti minimi
Extensor
indicis
Extensor
digitorum
Palmar and
dorsal
interossei
Extensor
pollicis longus
27 Wrist & Hand
Right hand. Muscle origins shown in red,
insertions in blue.
Abductor
digiti minimi
Extensor
pollicis brevis
Opponens
digiti minimi
Adductor
pollicis
Dorsal interossei
Abductor
pollicis longus
Extensor
carpi ulnaris
Extensor carpi
radialis brevis
Extensor carpi
radialis longus
Flexor digitorum
profundus
Dorsal (posterior) view.
A
Flexor digitorum
superficialis
Interossei
Flexor pollicis longus
Adductor pollicis
Abductor
digiti minimi
HG
Flexor
digiti minimi
brevis
Flexor pollicis brevis
and abductor
pollicis brevis
FD S
A
1st dorsal interosseus
Flexor carpi radialis
Opponens digiti minimi
Opponens pollicis
Extensor carpi ulnaris
Abductor pollicis longus
Abductor digiti minimi
Abductor pollicis brevis
Flexor carpi ulnaris
Flexor pollicis brevis
Ulna
1 1st palmar interosseus
Radius
2
2nd dorsal interosseus
3
3rd dorsal interosseus
4
2nd palmar interosseus
5
4th dorsal interosseus
6
3rd palmar interosseus
B
Palmar (anterior) view.
357
Upper Limb
Dorsum of the Hand
Fig. 27.21 Extensor retinaculum and dorsal carpal
tendon sheaths
Fig. 27.22 Muscles and tendons of the dorsum
Right hand, posterior (dorsal) view.
Intertendinous
connections
1st dorsal
interosseus
Abductor
digiti minimi
2nd dorsal
interosseus
Dorsal carpal
tendon
sheaths
④
①
⑤
Extensor
carpi ulnaris
Extensor
digiti minimi
Extensor carpi
radialis longus
tendon
③
Extensor
pollicis
longus
tendon
④
Extensor
pollicis brevis
⑤
Extensor
Extensor
digiti
indicis
minimi
tendon tendon
Extensor carpi radialis
brevis tendon
Extensor carpi radialis
longus tendon
Table 27.2
Extensor retinaculum
①
Extensor carpi
⑥
ulnaris tendon
②
③
⎧ Extensor pollicis brevis tendon
①⎨
Ulna
⎩ Abductor pollicis longus tendon
Radius
Extensor digitorum tendon ④
B
Posterior (dorsal) compartments, proximal view of section in Fig. 27.21A.
358
Extensor
digitorum
Brachioradialis
tendon
A Right hand, posterior (dorsal) view.
⎧
②⎨
⎩
Extensor
retinaculum
Abductor pollicis
longus tendon
Dorsal
tubercle
Dorsal tubercle
Extensor
indicis tendon
Extensor pollicis
longus tendon
⑥
③
3rd dorsal
interosseus
Extensor carpi
radialis brevis
tendon
Plane of section
in Fig. 27.21B
②
4th dorsal
interosseus
Extensor carpi
radialis longus
tendon
④
Dorsal compartments
for extensor tendons
Abductor pollicis longus
Extensor pollicis brevis
Extensor carpi radialis longus
Extensor carpi radialis brevis
Extensor pollicis longus
Extensor digitorum
Extensor indicis
⑤
Extensor digiti minimi
⑥
Extensor carpi ulnaris
Fig. 27.23 Dorsal digital expansion
27 Wrist & Hand
Right hand, middle finger. The dorsal digital expansion permits the
long digital flexors and the short muscles of the hand to act on all three
finger joints.
Distal
phalanx
Extensor
digitorum tendon
Lateral
bands
Dorsal
Dorsal
digital
expansion
Central band
3rd metacarpal
3rd dorsal interosseus
(fibers attached to
extensor tendon)
Collateral ligs.
Lumbrical slip
Deep
transverse
metacarpal lig.
Interosseous
slip
2nd dorsal
interosseus
3rd dorsal interosseus
(fibers attached
to bone)
Palmar lig.
Deep transverse
metacarpal lig.
Plane of
section
in B
2nd lumbrical
2nd
lumbrical
Deep transverse
metacarpal lig.
Anular lig. (A1)
Flexor
digitorum
superficialis
tendon
Flexor
digitorum
profundus
tendon
B
Cross section through 3rd metacarpal head, proximal view.
3rd dorsal
interosseus
2nd dorsal
interosseus
3rd
metacarpal
Extensor
digitorum
tendon
A
Posterior view.
Distal
phalanx
Dorsal digital
expansion
2nd dorsal
interosseus
Interosseous
slip
3rd
metacarpal
Extensor
digitorum
tendon
Anular ligs.
C
Radial view.
2nd
Lumbrical
slip Flexor
Flexor lumbrical
digitorum digitorum
superficialis profundus
tendon
tendon
Distal
Proximal
interphalangeal interphalangeal Vinculum Deep transverse
metacarpal lig.
longum
joint
joint
Vincula
Flexor
brevia digitorum
profundus
tendon
Metacarpophalangeal
joint
Flexor digitorum
superficialis tendon
DRadial view with common tendon sheath of flexor digitorum super­
ficialis and profundus opened.
359
Upper Limb
Muscle Facts (I)
The intrinsic muscles of the hand are divided into three groups: the
thenar, hypothenar, and metacarpal muscles (see p. 362). The thenar
Table 27.3
muscles are responsible for movement of the thumb, while the
­hypothenar muscles move the 5th digit.
Thenar muscles
Muscle
① Adductor pollicis
Origin
Insertion
Transverse head: 3rd metacarpal
(palmar surface)
Thumb (base
of proximal
phalanx) via
the ulnar
sesamoid
Oblique head: capitate bone,
2nd and 3rd metacarpals (bases)
② Abductor pollicis brevis
③ Flexor pollicis brevis
④ Opponens pollicis
Scaphoid bone and trapezium,
flexor retinaculum
Thumb (base
of proximal
phalanx) via
the radial
sesamoid
Superficial head: flexor
retinaculum
Deep head: capitate bone,
trapezium
Trapezium
Via the ulnar
sesamoid
Innervation
Action
Ulnar n. (C8, T1)
CMC joint of thumb: adduction
MCP joint of thumb: flexion
Median n. (C8, T1)
Via the radial
sesamoid
C8, T1
Superficial head:
median n. (C8, T1)
Deep head: ulnar n.
(C8, T1)
1st metacarpal (radial border)
Median n. (C8, T1)
CMC joint of thumb: abduction
CMC joint of thumb: flexion
CMC joint of thumb: opposition
CMC, carpometacarpal; MCP, metacarpophalangeal.
Fig. 27.24 Thenar and hypothenar
muscles
Right hand, palmar (anterior) view, schematic.
①
⑤
⑥
③
⑦
Table 27.4
Hypothenar muscles
Muscle
⑤ Opponens digiti
minimi
⑥ Flexor digiti minimi
brevis
Origin
Insertion
Innervation
Action
5th metacarpal (ulnar border)
Draws metacarpal in palmar
direction (opposition)
5th proximal phalanx (base)
MCP joint of little finger: flexion
Hook of hamate, flexor retinaculum
⑦ Abductor digiti
minimi
Pisiform bone
5th proximal phalanx (ulnar base) and dorsal
digital expansion of 5th digit
Palmaris brevis
Palmar aponeurosis (ulnar border)
Skin of hypothenar eminence
DIP, distal interphalangeal; MCP, metacarpophalangeal; PIP, proximal interphalangeal.
360
②④
Ulnar n.
(C8, T1)
MCP joint of little finger: flexion
and abduction of little finger
PIP and DIP joints of little finger:
extension
Tightens the palmar aponeurosis
(protective function)
Fig. 27.25 Thenar and hypothenar muscles
Right hand, palmar (anterior) view.
27 Wrist & Hand
5th proximal
phalanx
1st proximal
phalanx
Transverse
head
Oblique
head
5th metacarpal
Abductor
digiti minimi
Adductor
pollicis
Abductor
pollicis brevis
Opponens
digiti minimi
Hook of hamate
(under tendon)
Capitate
(under tendon)
Pisiform
(under tendon)
Trapezium
(under tendon)
Scaphoid
A
Removed: Flexor pollicis brevis, opponens
pollicis, and flexor digiti minimi brevis.
5th
proximal
phalanx
Flexor
digiti
minimi
brevis
Hook of
hamate
(under tendon)
1st
proximal
phalanx
Flexor
pollicis
brevis
Opponens
pollicis
Capitate
(under tendon)
Trapezium
(under tendon)
B
Removed: Adductor pollicis, abductor
pollicis brevis, abductor digiti minimi,
and opponens digiti minimi.
361
Upper Limb
Muscle Facts (II)
The metacarpal muscles of the hand consist of the lumbricals and
­interossei. They are responsible for the movement of the digits (with
the hypothenars, which act on the 5th digit).
Fig. 27.26 Metacarpal muscles of the hand
Right hand, palmar view, schematic.
S
D
F
A
Muscle
group
B
Dorsal interossei.
Dorsal
interossei
Palmar
interossei
Muscle
② 2nd
③ 3rd
Origin
Tendons of flexor digitorum profundus (radial sides)
L
C
Palmar interossei.
Insertion
Innervation
2nd digit (dde)
Median n.
(C8, T1)
3rd digit (dde)
4th digit (dde)
④ 4th
Tendons of flexor digitorum profundus (bipennate
from medial and lateral sides)
⑤ 1st
1st and 2nd metacarpals (adjacent sides, two heads)
2nd digit (dde)
2nd proximal phalanx (radial side)
⑥ 2nd
2nd and 3rd metacarpals (adjacent sides, two
heads)
3rd digit (dde)
3rd proximal phalanx (radial side)
⑦ 3rd
3rd and 4th metacarpals (adjacent sides, two heads)
3rd digit (dde)
3rd proximal phalanx (ulnar side)
⑧ 4th
4th and 5th metacarpals (adjacent sides, two heads)
4th digit (dde)
4th proximal phalanx (ulnar side)
⑨ 1st
2nd metacarpal (ulnar side)
2nd digit (dde)
2nd proximal phalanx (base)
⑩ 2nd
4th metacarpal (radial side)
4th digit (dde)
4th proximal phalanx (base)
⑪ 3rd
5th metacarpal (radial side)
5th digit (dde)
5th proximal phalanx (base)
dde, dorsal digital expansion; IP, interphalangeal; MCP, metacarpophalangeal.
362
Ö
Metacarpal muscles
① 1st
Lumbricals
G
Ä
A
Lumbricals.
Table 27.5
K
J H
5th digit (dde)
Ulnar n.
(C8, T1)
Action
2nd to 5th digits:
• MCP joints: flexion
• Proximal and distal IP joints:
extension
2nd to 4th digits:
• MCP joints: flexion
• Proximal and distal IP joints:
extension and abduction
from 3rd digit
2nd, 4th, and 5th digits:
• MCP joints: flexion
• Proximal and distal IP joints:
extension and adduction
toward 3rd digit
Fig. 27.27 Metacarpal muscles
Right hand, palmar (anterior) view.
27 Wrist & Hand
2nd distal phalanx, base
2nd proximal phalanx
2nd metacarpal
1st lumbrical
2nd lumbrical
3rd lumbrical
(often arises by
two heads)
4th lumbrical
(often arises
by two heads)
Hook of
hamate
Trapezoid
Pisiform
Radius
Ulna
Flexor digitorum
profundus tendons
2nd
through
5th
proximal
phalanges
3rd dorsal
interosseus
2nd dorsal
interosseus
4th dorsal
interosseus
1st dorsal
interosseus
2nd through
5th metacarpals
1st
metacarpal
A
Lumbrical muscles.
B
Dorsal interosseus muscles.
1st palmar
interosseus
2nd palmar
interosseus
3rd palmar
interosseus
2nd through
5th metacarpals
C
Palmar interosseus muscles.
363
28
Neurovasculature
Upper Limb
Arteries of the Upper Limb
Fig. 28.1 Arteries of the upper limb
Right limb with the forearm supinated, anterior view.
Vertebral a.
Subclavian a.
Brachiocephalic
trunk
Subclavian a.
Axillary a.
Acromial
br.
Thoracoacromial a.
Brachial a.
Thyrocervical
trunk
Left common carotid a.
Suprascapular a.
Left subclavian a.
Brachiocephalic trunk
Deltoid
br.
Pectoral
br.
Superior thoracic a.
Axillary a.
Thoracic aorta
Internal thoracic a.
Anterior and
posterior circumflex
humeral aa.
Radial a.
Ulnar a.
Subscapular a.
Circumflex
scapular a.
Deep a. of arm
Thoracodorsal a.
Brachial a.
Lateral
thoracic a.
Radial
collateral a.
Middle
collateral a.
Radial
recurrent a.
A
Main arterial segments.
Superior and inferior
ulnar collateral aa.
Ulnar recurrent a.
Common interosseous a.
Posterior
interosseous a.
Radial a.
Anterior
interosseous a.
Ulnar a.
Superficial
palmar br.
(radial a.)
Deep palmar arch
Superficial palmar arch
Common palmar
digital aa.
Palmar digital aa.
B
Course of the arteries.
364
Fig. 28.2 Branches of the subclavian artery
Fig. 28.3 Scapular arcade
Right side, anterior view.
Right side, posterior view.
Superficial cervical a.
(superficial br.)
Vertebral a.
Dorsal scapular a.
(deep br.)
Anterior
scalene
Transverse
cervical a.
Inferior
thyroid a.
Middle scalene
Posterior
scalene
Common
carotid a.
Suprascapular a.
Thyrocervical
trunk
Axillary a.
Subclavian a.
Thyrocervical
trunk
Suprascapular a.
Transverse
cervical a.
Acromial
brs.
Circumflex
scapular a.
Axillary a.
Anterior
circumflex
humeral a.
Posterior
circumflex
humeral a.
Dorsal
scapular a.
Subscapular a.
Deep a. of arm
Costocervical
trunk
Subclavian a.
Thoracodorsal a.
Clavicle
Deep cervical a.
28 Neurovasculature
Vertebral a.
Ascending
cervical a.
Brachial a.
1st rib
Supreme intercostal a.
Internal
thoracic a.
Fig. 28.4 Arteries of the forearm and hand
Right limb. The ulnar and radial arteries are interconnected
by the super­ficial and deep palmar arches, the perforating
branches, and the dorsal carpal network.
Recurrent interosseous a.
Posterior interosseous a.
Common
Common
interosseous a.
interosseous a.
Anterior interosseous a.
Dorsal
Posterior
interosseous a.
Radial a.
Dorsal carpal
network
Palmar
carpal
network
Dorsal
carpal a.
Perforating
br.
Dorsal
metacarpal a.
Dorsal and
palmar
digital aa.
Ulnar a.
Palmar
Deep
palmar arch
Radial a.
Deep palmar
arch
Anterior
interosseous a.
Interosseous
Interosseous
membrane
membrane
Palmar carpal
brs. (to palmar
carpal network)
Superficial palmar
arch
Metacarpal
Princeps
palmar a.
pollicis a.
Superficial
palmar
arch
Proper
palmar
digital aa.
Anterior
interosseous a.
(posterior br.)
Ulnar a. (dorsal
carpal br.)
Dorsal carpal
network
Radial a.
Dorsal carpal a.
Dorsal
metacarpal aa.
Perforating brs.
Common palmar
digital aa.
Radialis
indicis a.
Palmar
digital aa.
Right middle finger, lateral view.
A
Posterior
interosseous a.
Anterior (palmar) view.
B
Dorsal
digital aa.
Posterior (dorsal) view.
C
365
Upper Limb
Veins & Lymphatics of the Upper Limb
Fig. 28.5 Veins of the upper limb
Fig. 28.6 Veins of the dorsum
Right limb, anterior view.
Deltopectoral
groove
Right hand, posterior view.
Axillary v.
Cephalic v.
Subscapular v.
Cephalic v.
Basilic v.
Basilic v.
Basilic hiatus
Dorsal venous
network
Brachial vv.
Basilic v.
Intercapitular vv.
Dorsal digital vv.
Median
cubital v.
Median antebrachial v.
Basilic v.
Cephalic v.
Perforator vv.
Anterior interosseous vv.
Ulnar vv.
Radial vv.
Superficial
palmar venous
arch
Deep palmar
venous arch
Palmar
metacarpal vv.
Intercapitular vv.
Palmar digital vv.
A
Superficial veins.
B
Deep veins.
Clinical box 28.1
Venipuncture
The veins of the cubital fossa are frequently
used when drawing blood. In preparation,
a tourniquet is applied above the cubital
fossa. This allows arterial blood to flow,
but blocks the return of venous blood. The
resulting swelling makes the veins more
visible and palpable.
Fig. 28.7 Cubital fossa
Right limb, anterior view. The subcutaneous veins of the cubital fossa
have a highly variable course.
Cephalic v.
Median
antebrachial v.
Basilic v.
Median
cephalic v.
Median
cubital v.
Deep
median
cubital v.
Basilic v.
A
M -shaped.
366
Cephalic v.
Accessory
cephalic v.
Median
cephalic v.
Cephalic v.
B
Accessory cephalic vein.
Median
cubital v.
Perforator v.
Median
basilic v.
Median
basilic v.
Basilic v.
Basilic v.
Median
antebrachial v.
Median
antebrachial v.
C
Absent median cubital vein.
Lymph from the upper limb and breast drains to the axillary lymph nodes.
The superficial lymphatics of the upper limb lie in the subcutaneous
t­ issue, while the deep lymphatics accompany the arteries and deep
veins. Numerous anastomoses exist between the two systems.
28 Neurovasculature
Fig. 28.8 Lymph vessels of the upper limb
Right limb.
Axillary
lymph
nodes
Dorsolateral
arm territory
Dorsolateral
arm territory
Dorsomedial
arm territory
Middle
arm territory
Cubital l.n.
Radial bundle
territory
Ulnar bundle
territory
Radial bundle
territory
Middle
forearm
territory
Radial group
of lymphatics
Ulnar group
of lymphatics
Dorsal
descending
lymphatics
Anterior view.
A
Fig. 28.9 Lymphatic drainage of the hand
Right hand, radial view. Most of the hand drains to the axillary nodes
via cubital nodes. However, the thumb, index finger, and dorsum of the
hand drain directly.
Lymph vessels ascending from
the palmar to dorsal side
Posterior view.
B
Fig. 28.10 Axillary lymph nodes
Right side, anterior view. For surgical purposes, the axillary lymph nodes
are divided into three levels with respect to their relationship with the
pectoralis minor: lateral (level I), posterior (level II), or medial (level III).
They have major clinical importance in breast cancer (see p. 76).
Level I
Level II
Right
lymphatic
duct
Radial
bundle
territory
Level III
Radial group of
lymphatics
Pectoralis
minor
367
Upper Limb
Nerves of the Upper Limb: Brachial Plexus
Almost all muscles in the upper limb are innervated by the brachial
plexus, which arises from spinal cord segments C5 to T1. The anterior
rami of the spinal nerves give off direct branches (supraclavicular part
of the brachial plexus) and merge to form three trunks, six divisions
(three anterior and three posterior), and three cords. The infraclavicular
part of the brachial plexus consists of short branches that arise directly
from the cords and long (terminal) branches that traverse the limb.
Dorsal scapular n.
Suprascapular n.
Table 28.1
C5
Supraclavicular part
Posterior
cord
Lateral cord
Direct branches from the anterior rami or plexus trunks
Medial cord
T1
Subscapular n.
Phrenic n.
Axillary a.
N. to the
subclavius
Axillary n.
C5, C6
N. to the subclavius
C5–C6
Long thoracic n.
C5–C7
Lateral pectoral n.
Medial brachial
cutaneous n.
Lateral
cord
Musculocutaneous n.
Median n.
Medial and
lateral
pectoral nn.
Median n.
Lateral
root
Medial
cord
Thoracodorsal n.
Posterior
cord
Anterior
interosseous n.
C6–C7
C8–T1
Medial antebrachial
cutaneous n.
Medial brachial
cutaneous n.
Ulnar n.
C5–C7
Medial
root
Medial pectoral n.
Radial n.
Superficial
br.
C4–C5
Suprascapular n.
Short and long branches from the plexus cords
Musculocutaneous n.
Deep
br.
Dorsal scapular n.
Infraclavicular part
Long
thoracic n.
Radial n.
Nerves of the brachial plexus
T1
Ulnar n.
C7–T1
Upper subscapular n.
C5–C6
Thoracodorsal n.
C6–C8
Lower subscapular n.
Axillary n.
Radial n.
C5–C6
C5–T1
Clinical box 28.2
Injuries to nerves of the brachial plexus
Injuries of the brachial plexus can be complicated to diagnose but an
understanding of the basic organization of the plexus is essential. The
location of the injury can be determined by careful examination of the
type and specificity of the deficit. Nerves of the upper plexus innervate
muscles of the proximal limb such as those of the shoulder girdle and
arm, while nerves of the lower plexus innervate muscles of the distal
limb, such as the forearm and hand. Symptoms from injuries at the
root and cord levels will demonstrate this anatomical arrangement.
Additionally, a proximal injury to a nerve will elicit more broad-ranging
symptoms than a distal injury to that nerve.
368
Fig. 28.11 Brachial plexus
Posterior
root
Anterior
root
Right side, anterior view.
28 Neurovasculature
Posterior
rami
C5
Anterior
rami
C6
Upper trunk (C5–C6)
C7
Middle trunk (C7)
C8
Lower trunk (C8–T1)
T1
Anterior divisions
of C5–C7
Posterior
divisions
of C5–T1
Lateral cord
Anterior divisions
of C8–T1
Posterior cord
Medial cord
Axillary a.
Axillary n.
Lateral
root
Musculocutaneous n.
Ulnar n.
Radial n.
Medial
root
C5 spinal n.
Median
n.
Middle scalene
Dorsal scapular n.
Phrenic n.
Anterior scalene
Upper trunk
Median n.
A
Structure of the brachial plexus.
Middle trunk
Suprascapular n.
Vertebra prominens (C7)
C8 spinal n.
Lower trunk
T1 spinal n.
Interscalene space
Common carotid a.
Posterior
cord
Subclavian a.
Lateral
cord
Brachiocephalic
trunk
Subscapular n.
N. to the subclavius
Medial
cord
1st rib
Long thoracic n.
Axillary a.
Axillary n.
Intercostobrachial n.
Posterior
circumflex
humeral a.
Musculocutaneous n.
Medial brachial
cutaneous n.
Medial pectoral n.
Radial n.
Median n.
B
Course of the brachial plexus,
stretched for clarity.
Medial antebrachial
cutaneous n.
Ulnar n. Thoracodorsal n.
Lateral
pectoral n.
369
Upper Limb
Supraclavicular Branches & Posterior Cord
Fig. 28.12 Supraclavicular branches
The supraclavicular branches of the brachial plexus arise directly from
the plexus roots (anterior rami of the spinal nerves) or from the plexus
trunks in the lateral cervical triangle.
Right shoulder.
Transverse process
of atlas (C1)
Dorsal scapular n.
Levator
scapulae
Vertebra
prominens
(C7)
Scapula,
superior angle
Rhomboid
minor
Rhomboid
major
Scapula,
medial
border
Suprascapular n.
C4 spinal n.
Superior transverse
lig. of scapular
Suprascapular n. in
the scapular notch
Acromion
A
Dorsal scapular nerve. Posterior view.
Supraspinatus
Greater
tubercle
Scapular
spine
Atlas (C1)
Infraspinatus
C5 spinal n.
N. to the subclavius
Vertebra
prominens
(C7)
B
Suprascapular nerve. Posterior view.
Clavicle
Subclavius
1st rib
Serratus
anterior
Long
thoracic n.
Table 28.2
9th rib
C
Long thoracic nerve and nerve to the subclavius. Right lateral view.
370
Supraclavicular branches
Nerve
Level
Innervated muscle
Dorsal scapular n.
C4–C5
Levator scapulae
Rhomboids major and minor
Suprascapular n.
C5, C6
Supraspinatus
Infraspinatus
N. to the subclavius
C5–C6
Subclavius
Long thoracic n.
C5–C7
Serratus anterior
The posterior cord gives off three short branches (arising
at the level of the plexus cords) and two long branches
(terminal nerves, see pp. 372–373).
Right shoulder.
C5 spinal n.
Subscapularis
28 Neurovasculature
Fig. 28.13 Posterior cord: Short branches
Posterior
cord
Teres major
2nd rib (cut)
Upper subscapular n.
C6 spinal n.
Lower subscapular n.
T7 spinous
process
Thoracodorsal n.
A
Subscapular nerves. Anterior view.
Latissimus
dorsi
T12 spinous
process
Thoracolumbar fascia
Table 28.3
Iliac crest
Branches of the posterior cord
Nerve
Level
Innervated muscle
Short branches
Upper subscapular n.
Subscapularis
C5–C6
Subscapularis
Teres major
C6–C8
Latissimus dorsi
Axillary n.
C5–C6
See p. 372
Radial n.
C5–T1
See p. 373
Lower subscapular n.
Thoracodorsal n.
Sacrum
B
Thoracodorsal nerve. Posterior view.
Long (terminal) branches
371
Upper Limb
Posterior Cord: Axillary & Radial Nerves
Fig. 28.14 Axillary nerve: Cutaneous distribution
Right limb.
Clinical box 28.3
The axillary nerve may be damaged in a fracture of the surgical neck of
the humerus. This results in limited ability to abduct the arm and may
cause a loss of profile of the shoulder.
Supraclavicular nn.
Superior
lateral
brachial
cutaneous n.
(axillary n.)
Fig. 28.15 Axillary nerve
Right side, anterior view, stretched for clarity.
Atlas (C1)
C5 spinal n.
Middle scalene
Phrenic n.
Anterior
scalene
A
Anterior view.
B
Posterior view.
Axillary a.
Deltoid
Superior lateral
brachial cutaneous n.
(terminal sensory
br. of axillary n.)
Axillary n.
Table 28.4
Axillary nerve
(C5–C6)
Motor branches
Innervated muscles
Muscular brs.
Deltoid
Teres minor
Sensory branch
Superior lateral brachial cutaneous n.
372
Teres
minor
Posterior
cord
Fig. 28.16 Radial nerve: Cutaneous distribution
Fig. 28.17 Radial nerve
Right limb, anterior view with forearm pronated.
Posterior
brachial
cutaneous n.
Posterior cord
Axillary a.
Radial n.
Inferior
lateral
brachial
cutaneous n.
28 Neurovasculature
Anterior scalene
Posterior brachial
cutaneous n.
Posterior
antebrachial
cutaneous n.
Radial n. (in radial groove)
Inferior lateral
brachial cutaneous n.
Triceps
brachii
Radial n.,
superficial
br.
Radial tunnel
Posterior
antebrachial
cutaneous n.
A
Anterior view.
Table 28.5
B
Posterior view.
Radial nerve (C5–T1)
Motor branches
Innervated muscles
Brachialis (partial)
Triceps brachii
Muscular brs.
Anconeus
Brachioradialis
Supinator
Brachialis
Radial n., deep br.
(in supinator canal)
Posterior
interosseous n.
Brachioradialis
Radialis
muscle group
Radial n.,
superficial br.
Abductor
pollicis
longus
Extensor
digitorum
Extensor
pollicis brevis
Extensor
pollicis longus
Extensors carpi radialis longus and brevis
Supinator
Dorsal digital nn.
Extensor digitorum
Deep br. (terminal
br.: posterior
interosseous n.)
Extensor digiti minimi
Extensor carpi ulnaris
Extensors pollicis brevis and longus
Extensor indicis
Abductor pollicis longus
Sensory branches
Articular brs. from radial n.: Capsule of the shoulder joint
Articular brs. from posterior interosseous n.: Joint capsule of the wrist
and four radial metacarpophalangeal joints
Posterior brachial cutaneous n.
Inferior lateral brachial cutaneous n.
Posterior antebrachial cutaneous n.
Superficial brs.
Dorsal digital nn.
Ulnar communicating br.
Clinical box 28.4
Chronic radial nerve compression in the axilla (e.g., due to extended/
improper crutch use) may cause loss of sensation or motor function in
the hand, forearm, and posterior arm. More distal injuries (e.g., during
anesthesia) affect fewer muscles, potentially resulting in wrist drop with
intact triceps brachii function.
373
Upper Limb
Medial & Lateral Cords
The medial and lateral cords give off four short branches. The inter­
costobrachial nerves are included with the short branches of the
Table 28.6
Branches of the medial and lateral cords
Nerve
Level
Cord
Innervated muscle
Lateral pectoral n.
C5–C7
Lateral cord
Pectoralis major
Medial pectoral n.
C8–T1
Medial brachial
cutaneous n.
T1
Medial antebrachial
cutaneous n.
C8–T1
Intercostobrachial nn.
T2–T3
brachial plexus, although they are actually the cutaneous branches of
the 2nd and 3rd intercostal nerves.
Fig. 28.18 Medial and lateral cords: Short branches
Right side, anterior view.
Short branches
Pectoralis major and minor
Medial cord
— (sensory brs., do not
innervate any muscles)
C5–C7
Median n.
C6–T1
Ulnar n.
C7–T1
C7 spinal n.
Medial
pectoral n.
Long (terminal) branches
Musculocutaneous n.
Brachial plexus
(C5–T1)
Lateral cord
Medial cord
Coracobrachialis
Biceps brachii
Brachialis
Pectoralis
minor
Lateral
pectoral n.
See p. 376
Medial cord
See p. 377
Pectoralis
major
Fig. 28.19 Short branches of medial and lateral cords:
Cutaneous distribution
Medial and lateral pectoral nerves.
A
Medial brachial
cutaneous n.,
intercostobrachial n.
Posterior
ramus
Medial antebrachial cutaneous n.
Intercostobrachial nn.
Anastomosis
with medial
brachial
cutaneous n.
Intercostobrachial nerves.
B
A
Anterior view.
374
B
Posterior view.
2nd and 3rd
intercostal nn.
T3
vertebral
body
Anterior
cutaneous
br. of 2nd
intercostal n.
Lateral
cutaneous
br. of 4th
intercostal n.
Fig. 28.20 Musculocutaneous nerve
Table 28.7
Right limb, anterior view.
Lateral
cord
Anterior
scalene
Motor branches
Coracobrachialis
Muscular brs.
Intertubercular
groove
Innervated muscles
Biceps brachii
Brachialis
Sensory branches
Lateral antebrachial cutaneous n.
Axillary a.
Articular brs.: Joint capsule of the elbow (anterior
part)
Musculocutaneous n.
28 Neurovasculature
Coracoid
process
Musculocutaneous
nerve (C5–C7)
Note: Musculocutaneous n. innervation of the
arm is purely motor; innervation of the forearm
is purely sensory.
Biceps brachii,
short head
Biceps brachii,
long head
Coracobrachialis
Brachialis
Biceps brachii
Musculocutaneous n.
Fig. 28.21 Musculocutaneous nerve:
Cutaneous distribution
Brachialis
Lateral
antebrachial
cutaneous n.
Lateral
antebrachial
cutaneous n.
Ulna
Radius
A
Anterior view.
B
Posterior view.
375
Upper Limb
Median & Ulnar Nerves
The median nerve is a terminal branch arising from both the medial
and the lateral cords. The ulnar nerve arises exclusively from the
medial cord.
Fig. 28.22 Median nerve
Lateral cord
Fig. 28.23 Median nerve: Cutaneous distribution
Anterior
scalene
Right limb, anterior view.
Medial cord
Axillary a.
Lateral root
Median n.
Medial root
Median n.,
palmar
branch
Median n.
Common and
proper palmar
digital nn.
Proper
palmar
digital nn.
A
Anterior view.
B
Posterior view.
Medial epicondyle
Table 28.8
Articular br.
Pronator teres,
humeral head
Median nerve (C6–T1)
Motor branches
Pronator teres
Flexor carpi radialis
Pronator teres,
ulnar head
Anterior
interosseous n.
Flexor pollicis
longus
Recurrent br.
Palmaris longus
Muscular brs.
from anterior
interosseous n.
Flexor digitorum
profundus
Recurrent br.
Median n., palmar br.
1st and 2nd
lumbricals
Proper palmar
digital nn.
Palmaris longus
Pronator quadratus
Flexor pollicis longus
Flexor digitorum
profundus (radial half)
Abductor pollicis brevis
Pronator quadratus
Flexor pollicis brevis
(superficial head)
Opponens pollicis
Flexor retinaculum
376
Flexor carpi radialis
Direct muscular brs.
Flexor digitorum
superficialis
Flexor digitorum
superficialis
Common
palmar digital
nn.
Innervated muscles
Muscular brs.
from common
palmar digital nn.
Clinical box 28.5
Median nerve injury caused by fracture/
dislocation of the elbow joint may result in
compromised grasping ability and sensory loss
in the fingertips (see Fig. 28.23 for territories).
See also carpal tunnel syndrome (p. 391).
1st and 2nd lumbricals
Sensory branches
Articular brs.: Capsules of the elbow and wrist
joints
Palmar br. of median n. (thenar eminence)
Communicating br. to ulnar n.
Common palmar digital nn.
Proper palmar digital nn.
Fig. 28.24 Ulnar nerve: Cutaneous distribution
Fig. 28.25 Ulnar nerve
Right limb, anterior view.
28 Neurovasculature
Medial cord
Axillary a.
Ulnar n.
Ulnar n.,
palmar br.
Ulnar n.,
dorsal br.
Common
and proper
Dorsal
palmar
digital nn. digital nn.
A
Anterior view.
Table 28.9
Medial
epicondyle
B
Posterior view.
Ulnar groove
Ulnar nerve (C7–T1)
Motor branches
Innervated muscles
Flexor carpi ulnaris
Direct muscular brs.
Muscular br. from
superior ulnar n.
Flexor
carpi ulnaris
Flexor digitorum
profundus (ulnar half)
Palmaris brevis
Abductor digiti minimi
Flexor digiti minimi
brevis
Muscular brs. from
deep ulnar n.
Flexor
digitorum
profundus
Flexor
retinaculum
Dorsal br.
Palmar br.
Opponens digiti minimi
Superficial br.
3rd and 4th lumbricals
Deep br.
Palmar and dorsal
interosseous muscles
4th common
palmar digital n.
Adductor pollicis
Interossei
Flexor pollicis brevis
(deep head)
Sensory branches
Articular brs.: Capsules of the elbow, carpal, and
metacarpophalangeal joints
Dorsal br. (terminal brs.: dorsal digital nn.)
Palmar br.
Proper palmar digital n. (from superficial br.)
Common palmar digital n. (from superficial br.;
terminal brs.: proper palmar digital nn.)
Proper palmar
digital nn.
Clinical box 28.6
Ulnar nerve palsy is the most common
peripheral nerve damage. The ulnar nerve
is most vulnerable to trauma or chronic
compression in the elbow joint and ulnar
tunnel (see p. 391). Nerve damage causes
“clawing” of the hand and atrophy of the
interossei. Sensory losses are often limited
to the 5th digit.
377
Upper Limb
Superficial Veins & Nerves of the Upper Limb
Fig. 28.26 Superficial cutaneous veins and nerves
of the upper limb
Supraclavicular nn.
Supraclavicular nn.
Superior lateral brachial
cutaneous n. (axillary n.)
Intercostal nn.,
anterior
cutaneous brs.
Intercostobrachial n.
Medial
brachial
cutaneous n.
Cephalic v.
Inferior lateral brachial
cutaneous n. (radial n.)
Superior
lateral brachial
cutaneous n.
(axillary n.)
Intercostobrachial n.
Medial
brachial
cutaneous n.
Posterior brachial
cutaneous n.
(radial n.)
Basilic
hiatus
Inferior
lateral brachial
cutaneous n.
(radial n.)
Basilic v.
Medial
antebrachial
cutaneous n.
Lateral antebrachial
cutaneous n.
(musculocutaneous n.)
Median
cubital v.
Cephalic v.
Median
antebrachial v.
Posterior
antebrachial
cutaneous n.
(radial n.)
Basilic v.
Medial
antebrachial
cutaneous n.
Lateral
antebrachial
cutaneous n.
(musculocutaneous n.)
Accessory
cephalic v.
Perforating brs.
Medial
antebrachial
cutaneous n.
Cephalic v.
Radial n.,
superficial br.
Radial n.,
superficial br.
Ulnar n.,
palmar br.
Ulnar n.,
dorsal br.
Median n.,
palmar br.
Dorsal venous
network
Palmar
aponeurosis
Intercapitular vv.
Dorsal digital vv.
A
Anterior view. See pp. 392–393 for nerves of the palm.
378
B
Posterior view. See pp. 394–395 for nerves of the dorsum.
Fig. 28.27 Cutaneous innervation of the upper limb
Axillary n.
Medial brachial
cutaneous n.,
intercostobrachial n.
Medial
antebrachial
cutaneous n.
Radial n.
Musculocutaneous n.
Axillary n.
Medial brachial
cutaneous n.,
intercostobrachial n.
Musculocutaneous n.
Dorsal br.
Ulnar n.
Common
and
proper
palmar
digital nn.
Radial n.
Medial
antebrachial
cutaneous n.
Palmar br.
Palmar
br.
Median n.
Supraclavicular nn.
28 Neurovasculature
Supraclavicular nn.
Anterior
cutaneous
brs.
Intercostal nn.
Lateral
cutaneous
brs.
Ulnar n.
Dorsal
digital nn.
Common and
proper palmar
digital nn.
A
Anterior view.
Proper palmar
digital nn.
(median n.)
B
Posterior view.
Fig. 28.28 Dermatomes of the upper limb
C4
T2
C5
T2
T3
T3
T4
T4
T5
C4
C5
T5
C6
T1
T1
C6
C7
C7
C8
C8
A
Anterior view.
B
Posterior view.
379
Upper Limb
Posterior Shoulder & Arm
Fig. 28.29 Posterior shoulder
Right shoulder, posterior view. Raised: Trapezius (transverse part).
Windowed: Supraspinatus. Revealed: Suprascapular region.
Trapezius,
descending part
Omohyoid
Supraclavicular nn.
Posterior rami
of spinal nn.,
medial brs.
Suprascapular a.
(with superior transverse
lig. of scapula)
Suprascapular n.
(in scapular notch)
Trapezius,
transverse part
Coracoclavicular
lig.
Supraspinatus
Accessory n.
and brs. of
cervical plexus
Scapular spine
Deltoid
Posterior rami
of spinal nn.,
lateral brs.
Teres minor
Superior lateral
brachial cutaneous n.
(axillary n.)
Trapezius
(ascending part)
Inferior lateral
brachial cutaneous n.
(radial n.)
Latissimus
dorsi
380
Infraspinatus
Teres
major
Posterior brachial
cutaneous n.
(radial n.)
Table 28.10
Superior transverse
lig. of scapula
①
Transmitted
structures
Boundaries
②
①
Scapular
notch
Superior transverse
lig. of scapula,
scapula
Suprascapular a., v. and n.
②
Medial border
Scapula
Dorsal scapular a., v. and n.
③
Triangular
space
Teres major and minor,
triceps brachii
Circumflex scapular
a. and v.
⑤
④
Triceps hiatus
Triceps brachii, humerus,
teres major
Deep a. and v. of arm
and radial n.
④
⑤
Quadrangular
space
Teres major and minor,
triceps brachii, humerus
Posterior circumflex
humeral a. and v. and
axillary n.
Inferior transverse
lig. of scapula
28 Neurovasculature
Passageway
Neurovascular tracts of the scapula
③
Fig. 28.30 Triangular and quadrangular spaces
Clavicle
ARight shoulder, posterior
view. Windowed: Deltoid.
Supraspinatus
Acromion
Scapular spine
Suprascapular a. and n.
in scapular notch
Shoulder joint
capsule
Infraspinatus
Teres minor
Deltoid
Medial border
scapula
Axillary n. and posterior circumflex
humeral a. in quadrangular space
Triceps brachii,
lateral head
Circumflex
scapular a. in
triangular space
Teres major
Radial n.,
muscular brs.
Deep a. of arm
and radial n.
(in radial groove)
Triceps
brachii
Long
head
Lateral
head
In triceps
hiatus
Lateral
intermuscular
septum
B
Right shoulder, posterior view.
Windowed: Infraspinatus,
triceps brachii (lateral head).
381
Upper Limb
Anterior Shoulder
Fig. 28.31 Anterior shoulder: Superficial dissection
Right shoulder.
Clavicle
Subclavius
Superficial
thoracic fascia
Subclavian v.
Pectoralis
minor
Clavipectoral
fascia
Pectoralis
major
Axillary
fascia
A
Sagittal section through anterior wall.
External
jugular v.
Great auricular n.
Middle scalene m.
Posterior scalene m.
Supraclavicular nn.
Infraclavicular
fossa
Trapezius
Deltoid
Transverse cervical n.
Sternocleidomastoid
Brachial plexus
Omohyoid, inferior belly
Subclavian v.
Pectoralis major
(clavicular part)
Cephalic v.
(in deltopectoral
groove)
Clavipectoral fascia
Thoracoacromial a.
Medial pectoral n.
Lateral pectoral n.
Pectoralis major
(sternocostal part)
Biceps brachii
Brachial fascia
Latissimus dorsi
B
Anterior view. Removed: Platysma, muscle fasciae, superficial
layer of cervical fascia, and pectoralis major (clavicular part).
Revealed: Clavipectoral triangle.
382
Fig. 28.32 Shoulder: Transverse section
Right shoulder, inferior view.
Subtendinous
Tendon of
bursa of
biceps brachii,
subscapularis
long head
Deltoid
Pectoralis
major
Pectoralis
minor
Coracobrachialis
Anterior
Axillary a. and v.,
cords of brachial plexus
Subscapularis
28 Neurovasculature
Subdeltoid
bursa
Head of
humerus
Deltoid
Ribs
Serratus
anterior
Posterior
Glenoid
labrum
Glenoid
cavity
Infraspinatus
Rhomboid
major
Scapula
Fig. 28.33 Anterior shoulder: Deep dissection
Right limb, anterior view. Removed: Sternocleidomastoid,
omohyoid, and pectoralis major. This dissection reveals the
neurovascular contents of the lateral cervical triangle (see
pp. 538–539) and axilla (see pp. 384–385).
Suprascapular a.
Axillary a.
Thoracoacromial a.
Trapezius
Omohyoid,
inferior
belly (cut)
Interscalene
space
Brachial
plexus
Internal jugular v.
Common carotid a.
Scalene mm.
Phrenic n.
Inferior thyroid a.
Ascending cervical a.
Transverse cervical a.
Deltoid
External jugular v.
Thyrocervical trunk
Cephalic v.
Subclavian v.
Musculocutaneous n.
Clavicle
Pectoralis major
(cut)
Subclavius
Superior thoracic a.
Median n.
Long thoracic n.
Ulnar n.
Axillary a.
and v.
Pectoralis major
Pectoralis minor
Circumflex
scapular a.
Thoracodorsal a.
Subscapular a.
Lateral
thoracic a.
Medial and lateral
pectoral nn.
383
Upper Limb
Axilla
Fig. 28.34 Axilla: Dissection
Right shoulder, anterior view.
Median n. roots
Musculocutaneous n.
Thoracoacromial a.
Lateral
cord
Axillary
a. and v.
Subclavius
Long
thoracic n.,
superior
thoracic a.
Deltoid
Cephalic v.
Pectoralis
major
Lateral
pectoral n.
Medial
pectoral n.
Lateral
thoracic a.
Biceps
brachii
Median n.
Ulnar n.
Brachial
a. and v.
Pectoralis
major
Circumflex
scapular a.
Lower
subscapular n.
Long thoracic n.
Thoracodorsal
a. and n.
A
Removed: Pectoralis major and clavipectoral fascia.
Table 28.11
Walls of the axilla
Anterior wall
Pectoralis major
Pectoralis minor
Clavipectoral fascia
Lateral wall
Intertubercular groove
of humerus
Posterior wall
Subscapularis
Teres major
Latissimus dorsi
Medial wall
Lateral thoracic wall
Serratus anterior
Medial and
lateral cords
Pectoralis
major
Coracobrachialis
Biceps brachii,
short head
Serratus
anterior
Biceps brachii,
long head
Subscapularis
Axillary a. and v.
Rib
Head of
humerus
Posterior cord
384
Pectoralis
minor
Scapula
Thoracoacromial a.
Medial and lateral
cord brs.
Lateral cord
Axillary a.
Radial n.
Medial cord
Axillary v.
Brachial a.
28 Neurovasculature
Subscapular a.
Long thoracic n.,
superior thoracic a.
Upper subscapular n.
Lateral thoracic a.
Lower subscapular n.
Median n.
Ulnar n.
Axillary n.
Brachial v.
Thoracodorsal
a. and n.
Radial n.,
motor brs.
B
Removed: Anterior wall (pectoralis major
and minor, and clavipectoral fascia).
Retracted: Medial and lateral cords of the
brachial plexus.
Circumflex
scapular a.
Posterior
cord
Deltoid
Biceps brachii
tendon of long head
Coracoid
process
Pectoralis
major
Pectoralis
minor
Deltoid
Lateral and medial cords
Coracobrachialis
Suprascapular n.
(in scapular notch)
Radial n.
Upper subscapular n.
Lower subscapular n.
Biceps
brachii
Subscapularis
Biceps
fascia
Thoracodorsal n.
Posterior brachial
cutaneous n.
Removed: Medial and
C
lateral cords, and axillary
vessels. Revealed: Posterior cord.
Radial n.,
motor brs.
Medial head
Long head
Triceps brachii
Axillary n.
Serratus
anterior
Latissimus
dorsi
Teres major
385
Upper Limb
Anterior Arm & Cubital Region
Fig. 28.35 Brachial region
Right arm, anterior view. Removed: Deltoid,
pectoralis major and minor. Revealed: Medial
bicipital groove.
Musculocutaneous n.
(piercing the
Coracoid
coracobrachialis)
process
Biceps brachii
tendon of long head
Lateral
cord
Pectoralis major
Axillary
a. and v.
Deltoid
Medial cord
Median n.
Medial
intermuscular
septum
Bicipital
aponeurosis
Pectoralis
minor
Medial brachial cutaneous n.
Biceps
brachii
Medial antebrachial cutaneous n.
Brachial a.
Subscapularis
Cubital
fossa
Ulnar n.
Superior ulnar
collateral a.
Posterior
brachial
cutaneous n.
Teres
major
Long head
Brachialis
Ulnar n. (in
ulnar groove)
386
Medial head
Inferior ulnar
collateral a.
Triceps brachii
Latissimus
dorsi
Serratus
anterior
Fig. 28.36 Cubital region
Right elbow, anterior view.
Skin
28 Neurovasculature
Subcutaneous
tissue
Basilic v.
Biceps
brachii
Cephalic v.
Medial
antebrachial
cutaneous n.
Medial
epicondyle
Median cubital v.
Lateral
antebrachial
cutaneous n.
Deep median
cubital v.
(perforator v.)
Median
basilic v.
Cephalic v.
Biceps brachii
Brachialis
Basilic v.
Median antebrachial v.
Radial tunnel
Brachial a.,
median n.
Triceps brachii
Musculocutaneous n.
Brachioradialis
A
Cutaneous neurovascular structures in the
cubital fossa.
Muscular
brs.
Deep
Radial n.
br.
Superficial
br.
Medial antebrachial
Superficial fascia
cutaneous n.
Biceps
brachii tendon
Radial
recurrent a.
Ulnar a.
Cephalic v.
Basilic v.
Biceps brachii
(and fascia)
Brachial a. and v.
Median n.
Brachialis
Lateral antebrachial cutaneous n.
(musculocutaneous n.)
Biceps brachii tendon
Supinator
Inferior ulnar
collateral a.
Superior ulnar
collateral a.,
ulnar n.
Pronator teres
Perforator v.
Radial a.
Extensor carpi
radialis longus
Radial a.
Pronator
teres
Superior ulnar
collateral a.,
ulnar n.
Median n.
Humeral
head
Ulnar
head
Pronator
teres
Flexor
carpi radialis
Palmaris
longus
Flexor
carpi ulnaris
C
Deep cubital fossa. Removed: Biceps brachii
(distal muscle belly). Retracted: Brachio­
radialis.
Bicipital
aponeurosis
Brachioradialis
Cephalic v.
Median antebrachial v.
B
Superficial cubital fossa. Removed: Fasciae
and epifascial neurovascular structures.
387
Upper Limb
Anterior & Posterior Forearm
Fig. 28.37 Anterior forearm
Right forearm, anterior view.
Median n.
Median n.
Triceps
brachii
Biceps
brachii
Inferior ulnar
collateral a.
Superior ulnar
collateral a.,
ulnar n.
Brachialis
Medial
epicondyle
Brachial a.
Biceps
brachii
tendon
Pronator
teres
Biceps
brachii
Superior ulnar
collateral a.,
ulnar n.
Brachialis
Inferior ulnar
collateral a.
Brachioradialis
Medial
epicondyle
Radial n.,
superficial br.
Radial a.
Flexor
carpi radialis
Biceps
brachii
tendon
Brachioradialis
Bicipital
aponeurosis
Common interosseous a.
Palmaris
longus
Posterior interosseous a.
Pronator teres,
humeral head
Flexor
carpi radialis
Palmaris
longus
Pronator teres,
ulnar head
Recurrent interosseous a.
Flexor
digitorum
superficialis
Anterior interosseous a.
Extensor
carpi radialis
brevis
Flexor
carpi ulnaris
Extensor
carpi radialis
longus
Pronator
teres
Flexor
carpi ulnaris
Flexor carpi
radialis
Radial a.
Abductor
pollicis longus
Flexor
digitorum
superficialis
Radial a.
Palmaris longus
tendon
Ulnar a.
Flexor pollicis
longus
Median n.
Flexor
pollicis longus
Abductor
pollicis longus
Median n.
Pronator
quadratus
Flexor digitorum
superficialis
tendons
Ulnar a. and n.
Flexor
retinaculum
Flexor carpi
radialis tendon
Ulnar n.
(in ulnar tunnel)
Hypothenar
muscles
Thenar
muscles
Palmar
aponeurosis
A
Superficial layer. Removed: Fasciae and superficial
neurovasculature.
388
Hypothenar
muscles
Thenar
muscles
Palmar br.
of median n.
B
Middle layer. Partially removed: Superficial flexors (pronator
teres, flexor digitorum superficialis, palmaris longus, and
flexor carpi radialis).
Fig. 28.38 Posterior forearm
Right forearm, anterior view during pronation. Reflected: Anconeus and
triceps brachii. Removed: Extensor carpi ulnaris and extensor digitorum.
Triceps brachii,
lateral head
Biceps brachii
Musculocutaneous n.
Muscular
brs.
Radial n.
Brachial a.
Radial
collateral a.
Olecranon
Brachialis
Superficial
br.
Deep
br.
Anconeus
Biceps
brachii tendon
Brachioradialis
Pronator
teres
Extensor
carpi ulnaris
Interosseous
recurrent a.
Radial a.
Flexor
digitorum
superficialis,
humeroulnar
head
Ulnar
a. and n.
Passage
through
interosseous
membrane
Arterial
network of
elbow and
lateral
epicondyle
Supinator
Extensor
digitorum
Posterior
interosseous n.
Posterior
interosseous a.
Extensor
carpi ulnaris
Anterior interosseous a.
(piercing the membrane)
Median n.
Flexor
pollicis longus
Extensor
indicis
Abductor
pollicis longus
Interosseous
membrane
Radial a.
Extensor carpi
radialis longus
Extensor carpi
radialis brevis
and longus
Flexor
digitorum
superficialis,
radial head
Pronator
quadratus
Brachioradialis
28 Neurovasculature
Median n.
Flexor
digitorum
profundus
tendons
Ulnar
a. and n.
Flexor
digitorum
superficialis
tendons
Ulnar a.,
dorsal carpal br.
Extensor
retinaculum
Radial a.,
dorsal carpal br.
Extensor carpi
radialis brevis
tendon
Extensor
pollicis longus
Abductor
pollicis longus
Extensor
pollicis brevis
Extensor carpi
radialis longus
tendon
Radial a.
Extensor
pollicis
longus
tendon
C
Deep layer. Removed: Deep flexors.
389
Upper Limb
Carpal Region
Fig. 28.39 Anterior carpal region
Superficial
palmar arch
Right hand, anterior (palmar) view.
Median n.,
recurrent br.
Flexor digiti
minimi brevis
Flexor pollicis brevis,
superficial head
Abductor
digiti minimi
Abductor pollicis brevis
Palmaris brevis
Opponens pollicis
Palmar aponeurosis
(cut)
Flexor retinaculum
(transverse carpal lig.)
Pisiform
Radial a., superficial
palmar br.
Ulnar tunnel
Median n.
Palmar carpal lig.
Pronator quadratus
Ulnar a. and n.
Flexor carpi radialis
Flexor carpi
ulnaris
Flexor pollicis longus
Palmaris longus
tendon
Radial a.
Flexor digitorum
superficialis
A
Ulnar tunnel and deep palm.
Superficial
palmar arch
Median n.,
recurrent br.
Flexor pollicis brevis,
superficial head
Flexor digiti
minimi brevis
Abductor pollicis brevis
Abductor digiti
minimi
Opponens pollicis
Superficial br.
Flexor retinaculum
(transverse carpal lig.)
Ulnar n.
Deep br.
Ulnar a., deep br.
Radial a., superficial
palmar br.
Median n.
Ulnar a. and n.
Flexor carpi radialis
Flexor pollicis longus
Flexor digitorum
superficialis
Flexor carpi
ulnaris
Carpal tunnel with flexor retinaculum
B
transparent. Removed: palmaris brevis,
palmaris longus, palmar aponeurosis,
and palmar carpal ligament.
390
Radial a.
Extensor carpi radialis
longus and brevis
Fig. 28.40 Ulnar tunnel
Right hand, anterior
(palmar) view.
Palmar
aponeurosis
Hook of
hamate
Ulnar a. and n.,
superficial brs.
Hypothenar
muscles
Ulnar a. and n.,
deep brs.
Deep
palmar
arch
Superficial
palmar arch
Ulnar n.
A
Bony landmarks.
Superficial
br.
Deep
br.
Hook of
hamate
Ulnar a.
and n.
Ulnar tunnel
(proximal hiatus)
Ulnar tunnel
(distal hiatus)
Palmar carpal
lig.
Pisiform
Pisiform
Flexor carpi
ulnaris
Radial a.
Ulnar a.
and n.
28 Neurovasculature
Palmaris
brevis
Palmaris
longus
Flexor digitorum
superficialis tendons
B
Apertures and walls of the ulnar tunnel.
Fig. 28.41 Carpal tunnel:
Cross section
Right hand, proximal view. The
tight fit of sensitive neurovascular
structures with closely apposed,
frequently moving tendons in the
carpal tunnel often causes problems (carpal tunnel syndrome)
when any of the structures swell
or degenerate.
Scaphoid
Median n.
Trapezium
Thenar eminence
Flexor retinaculum
(transverse
carpal lig.)
Abductor pollicis
longus tendon
Ulnar a.
and n.
Pisiform
Extensor pollicis
brevis tendon
Extensor pollicis
longus tendon
Close-up in B
Hypothenar
eminence
Radial n.,
superficial br.
Triquetrum
Extensor carpi
radialis longus tendon
Extensor carpi
ulnaris tendon
Extensor digiti
minimi tendon
A
Cross section through the right wrist.
Extensor carpi
radialis brevis tendon
Hamate
Extensor digitorum
and extensor indicis tendons
Capitate
Flexor retinaculum
(transverse carpal lig.)
Flexor digitorum
superficialis tendons
Superficial palmar
a. and v.
Flexor carpi
radialis tendon
Palmar carpal
lig.
Ulnar a. and n.
Median n.
Pisiform
Flexor pollicis
longus tendon
Synovial cavity
Scaphoid
Triquetrum
B
Structures in the ulnar tunnel (green)
and carpal tunnel (blue).
Hamate
Capitate
Flexor digitorum profundus tendons
391
Upper Limb
Palm of the Hand
Fig. 28.42 Superficial neurovascular
structures of the palm
Right hand, anterior view.
Palmar digital nn.
(exclusive area of
median n.)
Palmar
digital n.
(exclusive
area of
ulnar n.)
Median n.,
palmar br.
Palmar digital aa.
Palmar
digital nn.
Ulnar n.,
palmar br.
Radial n.,
dorsal
digital n.
Common
palmar digital aa.
A
Sensory territories. Extensive overlap exists
between adjacent areas. Exclusive nerve
territories indicated with darker shading.
Palmar
digital nn.
of thumb
Flexor digiti
minimi brevis
Adductor
pollicis
Abductor
digiti minimi
Flexor pollicis
brevis, superficial head
Palmar
aponeurosis
Abductor
pollicis brevis
Palmaris
brevis
Flexor retinaculum
(transverse
carpal lig.)
Radial a., superficial
palmar br.
Radial a.
Ulnar a. and n.
Palmaris longus
tendon
Ulnar tunnel
B
Superficial arteries
and nerves.
Antebrachial
fascia
Fig. 28.43 Neurovasculature
of the finger
Right middle finger, lateral view.
Palmar digital n.,
dorsal branch
Metacarpophalangeal joint
Dorsal digital
a. and n.
Palmar digital a.
Digitopalmar
branches
Metacarpal
Palmar digital n.
Proper palmar Common palmar
digital a. and n.
digital a.
Nerves and arteries.
A
392
Vincula
brevia
Vincula
longa
Blood supply to the flexor
B
tendons in the tendon sheath.
Flexor
digitorum
profundus
tendon
Flexor
digitorum
superficialis
tendon
Fig. 28.44 Deep neurovascular structures
of the palm
Fig. 28.45 Innervation
patterns in the palm
Right hand,
anterior view.
Median
communicating
br.
Ulnar
communicating
br.
Palmar
digital aa.
and nn.
28 Neurovasculature
Right hand,
anterior view.
Palmar
digital nn.
B
Median and ulnar
communicating
brs. (20%).
1st dorsal
interosseous
Lumbricals
Common palmar
digital aa.
Adductor
pollicis
Flexor pollicis
brevis, superficial head
Superficial
palmar arch
Flexor digiti
minimi brevis
Abductor
digiti minimi
Ulnar n.,
superficial br.
Radial a., superficial palmar br.
Abductor
pollicis brevis
Opponens pollicis
Ulnar a. and
n., deep brs.
A
Ulnar communicating br. (45% of
cases).
Flexor retinaculum
Palmaris longus
Palmar carpal lig.
Radial a., superficial
palmar br.
Median n.
Ulnar a. and n.
Flexor digitorum
superficialis
Pronator
quadratus
Radial a.
Flexor
carpi ulnaris
Flexor pollicis longus
Flexor carpi radialis
Brachioradialis
C
No communicating
brs. (20%).
Palmar
digital nn.
Palmar
digital aa.
Common palmar
digital aa.
A
Superficial palmar arch.
Lumbricals
Abductor
digiti minimi
Adductor pollicis,
transverse head
Flexor digiti
minimi brevis
Palmar metacarpal aa.
Abductor pollicis
brevis
Flexor pollicis
brevis
Adductor pollicis,
oblique head
Deep palmar arch
Opponens digiti minimi
Superficial palmar arch
Ulnar n., deep br.
Ulnar n., superficial br.
Opponens pollicis
Radial a., superficial palmar br.
Ulnar a., deep br.
Ulnar a. and n.
Pronator quadratus
Flexor carpi ulnaris
Sensitive terminal br. of the
anterior interosseous n.
Radial a.
Anterior interosseous a.
B
Deep palmar arch.
393
Upper Limb
Dorsum of the Hand
Fig. 28.46 Cutaneous innervation of the dorsum of the hand
Right hand, posterior view.
Palmar digital nn.,
dorsal brs.
(median n.)
Dorsal
digital nn.
(radial n.)
Median n.,
dorsal brs.
of palmar
digital nn.
Exclusive area
of median n.
Dorsal digital n.
(exclusive area
of ulnar n.)
Dorsal digital nn.
(ulnar n.)
Ulnar n.,
dorsal br.
Radial n.,
superficial br.
and dorsal
digital nn.
Ulnar n.,
dorsal br.
Radial n.,
superficial br.
Posterior antebrachial
cutaneous n. (radial n.)
A
Nerves of the dorsum.
B
Sensory territories. Extensive overlap exists between adjacent areas.
Exclusive nerve territories indicated with darker shading.
Fig. 28.47 Anatomic snuffbox
Right hand, radial view. The three-sided “anatomic snuffbox” (shaded
green) is bounded by the tendons of insertion of the abductor pollicis
longus and extensors pollicis brevis and longus.
Extensor carpi radialis
longus
Extensor digitorum
and extensor
indicis tendons
Trapezium
Extensor carpi
radialis brevis
tendon
Extensor pollicis
longus tendon
Extensor
retinaculum
Radial n.,
superficial br.
1st dorsal
interosseous
Scaphoid
Radial a.
1st
metacarpal
394
Extensor pollicis
brevis tendon
Abductor
pollicis longus
tendon
Radial a.
Fig. 28.48 Neurovascular structures of the dorsum
28 Neurovasculature
Dorsal
digital aa.
Dorsal
interossei
Extensor pollicis
longus tendon
Dorsal
metacarpal aa.
Extensor
digitorum
tendon
Extensor pollicis
brevis tendon
Extensor carpi
radialis brevis and
longus tendons
Radial a.
Dorsal carpal
network
A
Superficial structures.
Radial a., dorsal
carpal br.
Extensor digiti
minimi tendon
Ulnar a., dorsal
carpal br.
Extensor
retinaculum
Extensor
carpi ulnaris
tendon
Dorsal
digital aa.
Extensor pollicis
longus tendon
Dorsal
metacarpal aa.
Extensor carpi
radialis brevis tendon
Radial a.
Extensor carpi
radialis longus
tendon
Dorsal carpal a.
(radial a.)
Extensor
retinaculum
Ulnar a., dorsal
carpal br.
Dorsal carpal
network
B
Deep structures.
395
29
Sectional & Radiographic Anatomy
Upper Limb
Sectional Anatomy of the Upper Limb
Fig. 29.1 Windowed dissection of the arm
and forearm
Right limb, anterior view.
Biceps
brachii
Deltoid
Brachialis
Medial
epicondyle,
common head
of flexors
Biceps brachii,
tendon of
insertion
Pectoralis
major
Bicipital
aponeurosis
Brachioradialis
Extensor
carpi radialis
longus
Coracobrachialis
Teres major
Extensor
carpi radialis
brevis
Biceps brachii,
long head
Radius
Pronator
teres
Flexor
carpi radialis
Palmaris
longus
Ulna
Biceps brachii,
short head
Flexor
carpi ulnaris
Flexor digitorum
superficialis
Humerus
Flexor
pollicis longus
Abductor
pollicis longus
Biceps
brachii
Thenar
muscles
Flexor retinaculum
(transverse
carpal ligament)
Brachialis
Brachioradialis
Palmaris
brevis
Medial
epicondyle
A Dissection of the arm.
396
Palmaris
longus
Palmar
aponeurosis
B Right forearm
Right limb, proximal view.
Posterior
Triceps brachii,
lateral head
Triceps brachii,
long head
Triceps brachii,
medial head
Radial nerve
Lateral intermuscular septum
of the arm
Medial intermuscular septum
of the arm
Humerus
Ulnar nerve
Brachialis
Brachial vein
29 Sectional & Radiographic Anatomy
Fig. 29.2 Cross-section through the arm
and forearm
Brachial artery
Median nerve
Musculocutaneous nerve
Biceps brachii,
long head
Biceps brachii,
short head
Anterior
A
Arm (plane of section in Fig. 29.1A)
Posterior
(dorsal)
Posterior
Extensor
interosseous nerve
pollicis brevis
Interosseous
of forearm
membrane
Extensor
of forearm
digiti minimi
Extensor
carpi ulnaris
Extensor
pollicis longus
Abductor
pollicis longus
Extensor
digitorum
Ulna
Flexor digitorum
profundus
Radius
Extensor carpi
radialis longus
Ulnar nerve
Anterior interosseous
nerve of forearm
Ulnar artery
Extensor carpi
radialis brevis
Flexor
carpi ulnaris
Brachioradialis
Flexor digitorum
superficialis
Radial nerve
(superficial branch)
Anterior
(palmar)
Pronator
teres
Radial artery
Flexor
pollicis longus
Flexor
carpi radialis
Palmaris
longus
Median nerve
B
Forearm (plane of section in Fig. 29.1B)
397
Upper Limb
Radiographic Anatomy of the Upper Limb (I)
Fig. 29.3 MRI of the arm
Transverse section, distal (inferior) view.
A
Biceps brachii
(short head, tendon)
Pectoralis major
Humerus
Coracobrachialis
Deltoid
Axillary a. and v.,
brachial plexus
B
Anterior humeral
circumflex a. and v.
Axillary n.
Subscapularis
Posterior humeral
circumflex a. and v.
C
Scapula
Triceps brachii
(long head)
Teres minor
A
Proximal arm. (Reproduced
from Moeller TB, Reif E. Pocket Circumflex scapular
a. and v.
Atlas of ­Sectional Anatomy,
Vol 2, 4th ed. New York, NY:
Thieme; 2014.)
Infraspinatus
Cephalic v.
Biceps brachii,
long head
Biceps brachii,
short head
Musculocutaneous n.
Brachialis
Humerus (shaft)
Radial n.
Triceps brachii,
lateral head
Mid-arm. (Reproduced
B
from Moeller TB, Reif E.
Atlas of Sectional Anatomy: The Musculoskeletal
System. New York, NY:
Thieme; 2009.)
Deep brachial a. and v.
Median n.
Brachial a. and v.
Basilic v.
Ulnar n.
Triceps brachii,
medial head
Triceps brachii,
long head
Cephaic v.
Biceps brachii
(long and short heads)
Musculocutaneous n.
Brachioradialis
Radial n., deep
brachial a. and v.
Brachial a. and v.
Median n.
Brachialis
Basilic v.
Triceps brachii
C
Distal arm. (Reproduced from
Moeller TB, Reif E. Pocket Atlas
of Sectional Anatomy, Vol 2,
4th ed. New York, NY: Thieme;
2014.)
398
Humerus (shaft)
Ulnar n., a. and v.
Fig. 29.4 MRI of the forearm
Transverse section, distal view.
Brachioradialis
Median n.
Pronator teres
Radial n.
Brachialis
Extensor carpi
radialis brevis
B
Flexor digitorum
superficialis
Head of radius
C
Ulnar n.
Anular lig.
Flexor carpi ulnaris
A
Proximal forearm. (Reproduced
from Moeller TB, Reif E. Pocket
Atlas of Sectional Anatomy,
Vol 2, 4th ed. New York, NY:
Thieme; 2014.)
Ulna
Proximal radioulnar
joint
Anconeus
Flexor digitorum
profundus
Flexor carpi radialis
29 Sectional & Radiographic Anatomy
Brachial a. and v.
Median cubital v.
A
Flexor digitorum
superficialis
Median n.
Ulnar a.,v., and n.
Radial a. and vv.
Flexor carpi ulnaris
Brachioradialis (tendon)
Flexor digitorum
profundus
Anterior interosseous a., v., and n.
Ulna
Cephalic v.
Basilic v.
Flexor pollicis longus
B
Mid-forearm. (Reproduced from Moeller
TB, Reif E. Atlas of
Sectional Anatomy:
The Musculoskeletal
System. New York,
NY: Thieme; 2009.)
Interosseous membrane
Extensor carpi radialis brevis
Extensor pollicis longus
Radius
Extensor indicis
Abductor pollicis longus
Extensor digitorum
Extensor carpi radialis
brevis (tendon)
Extensor carpi radialis
longus (tendon)
Radius
Radial a. and vv.
C
Distal forearm. (Reproduced
from Moeller TB, Reif E.
Pocket Atlas of Sectional
Anatomy, Vol 2, 4th ed.
New York, NY: Thieme;
2014.)
Flexor carpi radialis
Extensor carpi ulnaris
Extensor digitorum
Extensor carpi ulnaris
Ulna
Pronator quadratus
Flexor digitorum
profundus
Ulnar n.
Ulnar a. and vv.
Median n.
Flexor digitorum
superficialis
Flexor carpi ulnaris
399
Radiographic Anatomy of the Upper Limb (II)
Upper Limb
Fig. 29.5 Radiograph of the right shoulder
Anteroposterior view.
Head of
humerus
Glenoid
cavity
Fig. 29.6 Radiograph of the scapula
Infraglenoid
tubercle
Anteroposterior view. (Reproduced from Moeller TB, Reif E. Pocket
Atlas of Radiographic Anatomy, 3rd ed. New York, NY: Thieme; 2010.)
Acromioclavicular
joint
Clavicle
Acromion
Coracoid process
Greater
tubercle
Lesser
tubercle
Superior angle
Humerus, head
Articular surface
Scapular spine
Scapula, neck
Scapula, lateral margin
Scapula, medial
margin
Scapula, inferior
angle
Fig. 29.7 Diagnostic ultrasound of the
anterior region of the left shoulder
Transverse section at the level of the intertubercular
groove. (Reproduced from Konerman W, Gruber G.
Ultraschalldiagnostik der Bewegungsorgane, 2nd ed.
Stuttgart: Thieme; 2006.)
Subscapularis
tendon
Lesser
tubercle
Tendon of
biceps brachii,
long head
Deltoid
Tendon of
biceps brachii,
long head
Greater
tubercle
Lesser
tubercle
Greater
tubercle
A Sonogram.
400
Deltoid
B Schematic of the transverse section.
Fig. 29.8 MRI of the right shoulder
joint in three planes
Acromion
Acromioclavicular joint
Trapezius
Tendon of
supraspinatus
Supraspinatus
Head of humerus
Suprascapular
a., v., and n.
Deltoid
Glenoid
cavity
Biceps brachii,
long head
Subscapularis
Axillary n.,
posterior humeral
circumflex
a. and v.
Intercostal mm.
Latissimus
dorsi
Serratus
anterior
A Coronal section, anterior view.
Subacromial
bursa
29 Sectional & Radiographic Anatomy
Subacromial
bursa
Acromion
Deltoid,
clavicular part
Supraspinatus
Head of
humerus
Infraspinatus
Teres minor
Subscapularis
Axillary n.
Posterior humeral
circumflex
a. and v.
Pectoralis
major
Teres major
Deltoid,
scapular part
Biceps brachii,
short head
Biceps brachii,
long head
B Sagittal section, lateral view.
Lesser
tubercle
Tendon of
biceps brachii,
long head
Deltoid,
acromial part
Greater
tubercle
Head of
humerus
Glenoid
cavity
Deltoid,
scapular part
C Transverse section, inferior view.
Subscapular
a., v., and n.
Deltoid,
clavicular part
Glenoid
labrum
Pectoralis
minor
Pectoralis
major
Subclavius
Axillary
a. and v.
Brachial
plexus
Serratus
anterior
Subscapularis
Scapula
Infraspinatus
401
Upper Limb
Radiographic Anatomy of the Upper Limb (III)
Fig. 29.9 Radiograph of the elbow
Anteroposterior view. (Reproduced from Moeller TB, Reif E.
Pocket Atlas of Radiographic Anatomy, 3rd ed. New York,
NY: Thieme; 2010.)
Humerus
Olecranon fossa
Medial epicondyle
Lateral epicondyle
Olecranon
Capitulum
Trochlea
Humeroradial joint
Humeroulnar joint
Radial head
Coronoid process
Radial tuberosity
Proximal radioulnar joint
Fig. 29.10 Radiograph of the elbow
Lateral view. (Reproduced from Moeller TB,
Reif E. Pocket Atlas of Radiographic Anatomy,
3rd ed. New York, NY: Thieme; 2010.)
Humerus
Coronoid fossa
Coronoid process
Radial head
Olecranon fossa
Radial tuberosity
Lateral epicondyle
Humeroradial joint
Radius
Humeroulnar joint
Olecranon
402
Ulna
Fig. 29.11 MRI of
the elbow
Triceps brachii
Humerus
Brachialis
Posterior fat
body of elbow
Anterior fat body and
coronoid fossa
Olecranon
Humerus, trochlea
Biceps brachii, tendon
Coronoid
process
Brachioradialis
Ulnar a. and v.
Radial a. and v.
Pronator teres
A Sagittal section through
the humeroulnar joint.
Flexor digitorum
profundus
Radial n.
Median n.
29 Sectional & Radiographic Anatomy
(Reproduced from
Moeller TB, Reif E. Atlas
of Sectional Anatomy:
The Musculoskeletal
System. New York, NY:
Thieme; 2009.)
Biceps brachii
Brachialis
Trochlear notch
Humerus, capitulum
Radial n.
Radial head
Humeroradial joint
Proximal radioulnar
joint
Biceps brachii,
tendon
B Sagittal section through
the humeroulnar and
humeroradial joints.
Radial tuberosity
Supinator
Flexor digitorum
profundus
Flexor digitorum
superficialis
Pronator teres,
ulnar head
Brachioradialis
Brachioradialis
Brachialis
Extensor carpi
radialis longus
Lateral epicondyle
Pronator teres
Humeroradial joint
Medial collateral
lig.
Radial head
Supinator
Radial tuberosity
C Coronal section through the
humeroulnar and humeroradial
joints.
Medial
epicondyle
Extensor digitorum
Humeroulnar
joint
Ulna, coronoid
process
Brachialis
Flexor carpi radialis
403
Upper Limb
Radiographic Anatomy of the Upper Limb (IV)
Fig. 29.12 Radiograph of the hand
(Reproduced from Moeller TB, Reif E. Pocket Atlas of Radiographic
Anatomy, 3rd ed. New York, NY: Thieme; 2010.)
Distal phalanx
Distal
interphalangeal joint
Head of proximal phalanx
Proximal
interphalangeal joint
Middle
phalanx
Metacarpophalangeal
joint
Base of proximal phalanx
Proximal
phalanx
Metacarpal
Metacarpal
head
Metacarpal base
Metacarpal
base
Trapezoid
Capitate
Scaphoid
Triquetrum
Radius, styloid process
Lunate
Radius, styloid process
Pisiform
Lunate
Triquetrum
Trapezium
Hamate
Trapezium
Scaphoid
Capitate and
hamate
Trapezoid
Ulna, styloid
process
Ulna, styloid
process
A Anteroposterior view.
B Oblique view.
Fig. 29.13 MRI of the right wrist
Transverse section, distal view. (Reproduced from Moeller TB, Reif E.
Atlas of Sectional Anatomy: The Musculoskeletal System. New York,
NY: Thieme; 2009.)
Dorsal
Hamate
Capitate
Trapezoid
Flexor digitorum
profundus, tendon
Radial a. and vv.
Ulnar n.,
deep branch
Flexor digitorum
superficialis, tendon
Trapezium
Ulnar n.
Flexor carpi
radialis, tendon
Ulnar a. and vv.
Abductor pollicis
longus, tendon
404
Median n.
Flexor
retinaculum
Fig. 29.14 MRI of the hand
Adductor pollicis
Opponens
digiti minimi
Flexor pollicis brevis,
deep head
Flexor digiti minimi
Abductor pollicis
Abductor digiti minimi
Opponens pollicis
Flexor pollicis
longus, tendon
Hamate, hook
Metacarpal I, base
Pisiform
Trapezium
Palmar radiocarpal
lig.
Scaphoid
29 Sectional & Radiographic Anatomy
(Reproduced from Moeller TB,
Reif E. Atlas of Sectional
Anatomy: The Musculoskeletal
System. New York, NY: Thieme;
2009.)
Flexor digitorum
profundus, tendons
A Coronal section through the carpal tunnel.
Dorsal digital
aa. and nn.
Collateral lig.
Metacarpophalangeal
joint
Proximal phalanx,
base
Interosseous
muscles
Metacarpal,
head
Carpometacarpal
joint
Metacarpal II,
base
Trapezoid
Hamate
Capitate
Scaphoid
Ulna
Radius
B Coronal section through the palm.
Metacarpal II-IV,
shafts
Extensor digitorum,
tendons
Dorsal
Dorsal (extensor)
expansion
Dorsal
interosseous
mm.
Palmar interosseous
mm.
Collateral lig.
Metacarpal V, head
Lumbricals
Palmar digital
aa. and nn.
First proximal
phalanx
C Transverse section through
the palm, distal view.
Flexor pollicis
longus, tendon
Flexor digitorum
superficialis, tendon
Flexor digitorum
profundus, tendon
405
Lower Limb
30 Surface Anatomy
34 Neurovasculature
Surface Anatomy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 408
31 Hip & Thigh
Bones of the Lower Limb . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Femur . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Hip Joint: Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Hip Joint: Ligaments & Capsule . . . . . . . . . . . . . . . . . . . . . . .
Anterior Muscles of the Hip, Thigh & Gluteal Region (I) . . . .
Anterior Muscles of the Hip, Thigh & Gluteal Region (II) . . .
Posterior Muscles of the Hip, Thigh & Gluteal Region (I) . . .
Posterior Muscles of the Hip, Thigh & Gluteal Region (II) . . .
Muscle Facts (I) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Muscle Facts (II) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Muscle Facts (III) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
410
412
414
416
418
420
422
424
426
428
430
32 Knee & Leg
Tibia & Fibula . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Knee Joint: Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Knee Joint: Capsule, Ligaments & Bursae . . . . . . . . . . . . . . .
Knee Joint: Ligaments & Menisci . . . . . . . . . . . . . . . . . . . . . .
Cruciate Ligaments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Knee Joint Cavity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Muscles of the Leg: Anterior & Lateral Compartments . . . . .
Muscles of the Leg: Posterior Compartment . . . . . . . . . . . . .
Muscle Facts (I) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Muscle Facts (II) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
432
434
436
438
440
442
444
446
448
450
33 Ankle & Foot
Bones of the Foot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Joints of the Foot (I) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Joints of the Foot (II) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Joints of the Foot (III) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Ligaments of the Ankle & Foot . . . . . . . . . . . . . . . . . . . . . . . .
Plantar Vault & Arches of the Foot . . . . . . . . . . . . . . . . . . . . .
Muscles of the Sole of the Foot . . . . . . . . . . . . . . . . . . . . . . .
Muscles & Tendon Sheaths of the Foot . . . . . . . . . . . . . . . . .
Muscle Facts (I) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Muscle Facts (II) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
452
454
456
458
460
462
464
466
468
470
Arteries of the Lower Limb . . . . . . . . . . . . . . . . . . . . . . . . . . .
Veins & Lymphatics of the Lower Limb . . . . . . . . . . . . . . . . .
Lumbosacral Plexus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Nerves of the Lumbar Plexus . . . . . . . . . . . . . . . . . . . . . . . . .
Nerves of the Lumbar Plexus: Obturator & Femoral Nerves . .
Nerves of the Sacral Plexus . . . . . . . . . . . . . . . . . . . . . . . . . . .
Nerves of the Sacral Plexus: Sciatic Nerve . . . . . . . . . . . . . . .
Superficial Nerves & Veins of the Lower Limb . . . . . . . . . . . .
Topography of the Inguinal Region . . . . . . . . . . . . . . . . . . . .
Topography of the Gluteal Region . . . . . . . . . . . . . . . . . . . . .
Topography of the Anterior, Medial & Posterior Thigh . . . . .
Topography of the Posterior Compartment
of the Leg & Foot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Topography of the Lateral & Anterior Compartments
of the Leg & Dorsum of the Foot . . . . . . . . . . . . . . . . . . . .
Topography of the Sole of the Foot . . . . . . . . . . . . . . . . . . . .
472
474
476
478
480
482
484
486
488
490
492
494
496
498
35 Sectional & Radiographic Anatomy
Sectional Anatomy of the Lower Limb . . . . . . . . . . . . . . . . . .
Radiographic Anatomy of the Lower Limb (I) . . . . . . . . . . . .
Radiographic Anatomy of the Lower Limb (II) . . . . . . . . . . . .
Radiographic Anatomy of the Lower Limb (III). . . . . . . . . . . .
Radiographic Anatomy of the Lower Limb (IV). . . . . . . . . . . .
500
502
504
506
508
30
Surface Anatomy
Lower Limb
Surface Anatomy
Fig. 30.1 Palpable bony prominences of the lower limb
Right limb.
Iliac crest
Anterior
superior
iliac spine
Greater
trochanter
Iliac crest
Posterior
superior
iliac spine
Pubic
tubercle
Sacrum
Pubic
symphysis
Ischial
tuberosity
Fig. 30.2 Regions of the lower limb
Right leg.
Patella
Lateral tibial
condyle
Medial tibial
condyle
Medial
epicondyle
Lateral
epicondyle
Head of fibula
Tibial
tuberosity
Anterior thigh
region
Medial
surface
of tibia
Lateral
malleolus
Tuberosity
of 5th
metatarsal
Anterior genual
region
Medial
malleolus
Navicular
tuberosity
Metatarsophalangeal
joints
Navicular
tuberosity
Calcaneal
tuberosity
Tuberosity of
5th metatarsal
Posterior leg
region
Interphalangeal joints of the foot
A
Anterior view.
Femoral trigone
B
Posterior view.
Anterior leg
region
Dorsum
of the foot
A
Anterior view.
408
Iliac crest
Tensor fascia
lata
Gluteus
maximus
Gluteus
medius
Rectus
femoris
30 Surface Anatomy
Fig. 30.3 Palpable musculature of the lower limb
Iliotibial
tract
Sartorius
Semimembranosus,
semitendinosus
Vastus
medialis
Vastus
lateralis
Biceps
femoris
Gluteal region
Gastrocnemius
Posterior
thigh region
Fibularis
longus
Gastrocnemius
Tibialis
anterior
Tibia
Calcaneal
(Achilles’)
tendon
Popliteal
region
Posterior
leg region
Extensor
hallucis
longus
A
Anterior view, left limb.
Extensor
digitorum
tendons
B Posterior view, right limb.
Lateral retromalleolar region
Calcaneal region
Sole of the foot
B
Posterior view.
409
31
Hip & Thigh
Lower Limb
Bones of the Lower Limb
The skeleton of the lower limb consists of a coxal (hip) bone and a free
limb. The paired coxal bones attach to the trunk at the sacroiliac joint
to form the pelvic girdle (see p. 230), and the free limb, divided into a
thigh, leg, and foot, attaches to the pelvic girdle at the hip joint. Stability of the pelvic girdle is important in the distribution of weight from
the upper body to the lower limbs.
Fig. 31.1 Bones of the lower limb
Posterior superior
iliac spine
Coxal bone
Iliac
crest
Coxal
bone
Iliac crest
Pelvic
girdle
(right
side)
Coxal bone
Anterior superior
iliac spine
Neck of
femur
Hip joint
Ischial
spine
Pubic tubercle
Greater trochanter
Ischial
tuberosity
Lesser
trochanter
Thigh
Lesser
trochanter
Femur
Greater
trochanter
Femur
Medial
condyle
Patella
Patella
Tibial
plateau
Head of fibula
Lateral
condyle
Medial
epicondyle
Knee joint
Lateral tibial
condyle
Knee joint
Tibial
tuberosity
Medial
tibial
condyle
Head of fibula
Tibia
Tibia
Fibula
Fibula
Fibula
Leg
Medial
malleolus
Ankle
mortise
Talocrural
(ankle) joint
Lateral
malleolus
Lateral
malleolus
Calcaneus
Tarsals
Metatarsals
Foot
Tuberosity of
5th metatarsal
Calcaneus
Phalanges
A
Anterior view.
410
B
Right lateral view.
C
Posterior view.
Fig. 31.3 The coxal bones and their relation to the
­vertebral column.
Right lateral view. The line of gravity runs vertically from the whole-body center of gravity
to the ground with characteristic points of
intersection.
The paired coxal bones and sacrum form the pelvic girdle (see p. 230).
31 Hip & Thigh
Fig. 31.2 Line of gravity
L4
External auditory canal
Dens of axis (C2)
Sacroiliac
joint
Inflection points
of vertebral
column
Sacrum
Coxal bone
Coccyx
Hip joint
Center of gravity
Hip joint
Pubic
symphysis
Knee joint
A
Anterior view.
Ankle joint
L4
Coxal
bone
Neck of
femur
Sacrum
Greater
trochanter
Ischial
tuberosity
B
Posterior view.
411
Lower Limb
Femur
Fig. 31.4 Femur
Right femur. The femur articulates proximally with the acetabulum of
the pelvis at the hip joint and distally with the tibia at the knee joint.
Head
Fovea
Trochanteric
fossa
Neck
Greater
trochanter
Greater
trochanter
Intertrochanteric crest
Lesser
trochanter
Intertrochanteric line
Pectineal
line
Gluteal
tuberosity
Shaft
Lateral
lip
Medial
lip
Medial
supracondylar
line
Lateral
supracondylar
line
Adductor
tubercle
Popliteal surface
Medial
epicondyle
Intercondylar
line
Lateral
epicondyle
Lateral
epicondyle
Lateral
condyle
Lateral
condyle
A
Anterior view.
412
Linea
aspera
Patellar
surface
Medial
condyle
Intercondylar
notch
B
Posterior view.
Acetabular
labrum
Patella
31 Hip & Thigh
Patellar
surface
of femur
Acetabulum
Head of
femur
Fovea of
femoral
head
Fig. 31.5 Hip joint: Transverse section
Neck of
femur
Right hip joint, superior view.
Greater
trochanter
Medial
condyle
Iliopectineal
bursa
Lateral
condyle
C
Proximal view. The acetabulum has been
sectioned in the horizontal plane.
Head of
femur
Patellar surface of
femur (femoral trochlea)
Fibrous
membrane
Lig.
of head
of femur
Neck of
femur
Acetabulum
Patellar
surface
of femur
Lateral
condyle
Greater
trochanter
Trochanteric
bursa
Ischium
Medial
condyle
Intercondylar
notch
DDistal view.
Clinical box 31.1
Rotation of the femoral head
The acetabular rim is oriented anteroinferiorly relative to the sagittal plane.
At birth, the aperture angle measures approximately 7 degrees but increases
to 17 degrees by adulthood (A). This angle affects the stability and “seating”
of the femoral head in the hip joint. When the femoral head is centered in the
17°
acetabulum, the distal femur and thus the knee joint, point slightly inward.
Note how external (B) and internal (C) rotation of the femoral head affect the
orientation of the knee joint.
Acetabular
inlet plane
Sagittal (anterior)
aperture angle
Patella
A
Sagittal plane
B
C
413
Hip Joint: Overview
Lower Limb
Fig. 31.6 Right hip joint
The head of the femur articulates with the acetabulum of the pelvis at
the hip joint, a special type of spheroidal (ball-and-socket) joint. The
roughly spherical femoral head (with an average radius of curvature of
approximately 2.5 cm) is largely contained within the acetabulum.
Iliac crest
Anterior
superior
iliac spine
Iliac crest
Bony acetabular
rim
Head of femur
Posterior superior
iliac spine
Greater
trochanter
Intertrochanteric line
Pubic
tubercle
Neck
of femur
Lesser
trochanter
Posterior
inferior
iliac spine
Acetabular
rim
Head of femur
Greater
trochanter
Neck of
femur
Intertrochanteric crest
A
Anterior view.
Lesser
trochanter
Ischial
spine
Gluteal
tuberosity
Ischial
tuberosity
Pectineal
line
Linea
aspera
B
Posterior view.
414
31 Hip & Thigh
Fig. 31.7 Hip joint: Coronal section
Right hip joint, anterior view.
Epiphyseal
line
Clinical box 31.2
Ilium
Neck of
femur
Acetabulum
Head of
femur
Lig. of
head of
femur
Fractures of the femur
Femoral fractures caused by falls in patients with
osteoporosis are most frequently located in the
neck of the femur. Femoral shaft fractures are less
frequent and are usually caused by strong trauma
(e.g., a car accident).
Acetabular
fossa
Acetabular
labrum
Medial
femoral
neck fractures
Lateral femoral
neck fracture
Peritrochanteric
femoral fracture
Greater
trochanter
Subtrochanteric
femoral fracture
Shaft of
femur
Trochanteric
bursa
Clinical box 31.3
Diagnosing hip dysplasia and dislocation
Ultrasonography, the most important imaging method for screening
the infant hip, is used to identify morphological changes such as hip
dysplasia and dislocation. Clinically, hip dislocation presents with instability
and limited abduction of the hip joint, and leg shortening with asymmetry
of the gluteal folds.
Ilium
Bony
acetabular rim
Bony
acetabular rim
Acetabular
labrum
Acetabular
labrum
Ossification
center
Femur
A
Normal hip joint in a 5-month-old.
Inferior
margin
of ilium
Femur
Inferior
margin
of ilium
B
Hip dislocation and dysplasia in a 3-month-old.
415
Lower Limb
Hip Joint: Ligaments & Capsule
The hip joint has three major ligaments: iliofemoral, pubofemoral,
and ischiofemoral. The iliofemoral, the strongest of these, provides an
important constraint for the hip joint: it prevents the pelvis from tilting
posteriorly in the upright stance, without the need for muscular effort.
It also limits adduction of the extended limb and stabilizes the pelvis
on the stance side during gait. A fourth ligament, the zona orbicularis
(anular ligament) is not visible externally and encircles the femoral neck
like a buttonhole.
Fig. 31.8 Ligaments of the hip joint
Right hip joint.
L5 vertebra
Posterior superior
iliac spine
Iliac crest
Anterior superior
iliac spine
Posterior
sacroiliac
ligs.
Inguinal
lig.
Sacrum
Pubofemoral
lig.
Sacrospinous
lig.
Pubic tubercle
Ischial spine
Iliofemoral
lig.
Sacrotuberous
lig.
Greater trochanter
Ischiofemoral
lig.
A Lateral view
Femur
Iliolumbar lig.
Iliolumbar
lig.
Iliac crest
L5 vertebra
Anterior
sacroiliac ligs.
Posterior
sacroiliac
ligs.
Sacrotuberous
lig.
Ischial spine
Sacrospinous
lig.
Iliofemoral
lig.
Ischial spine
Greater
trochanter
416
Iliac crest
Sacral
promontory
Inguinal
lig.
B Anterior view
L4 vertebra
Anterior longitudinal lig.
L5 vertebra
Anterior
superior
iliac spine
Intertrochanteric line
L4 vertebra
Pubic
symphysis
Lesser
trochanter
Posterior
superior
iliac spine
Iliofemoral lig.
Greater
trochanter
Sacrospinous
lig.
Intertrochanteric
crest
Sacrotuberous
lig.
Lesser
trochanter
Ischial
tuberosity
Pubofemoral
lig.
C Posterior view
Ischiofemoral
lig.
Fig. 31.9 Weakness in the joint capsule
A Anterior view
31 Hip & Thigh
Right hip joint. Weak spots in the joint capsule
(color-shaded areas) are located between the
joint ligaments. External trauma may cause the
femoral head to dislocate from the acetabulum
at these sites.
Iliofemoral
lig.
Iliofemoral
lig.
Pubofemoral
lig.
B Posterior view
Ischiofemoral
lig.
Fig 31.10 Synovial membrane
of the joint capsule
Synovial membrane
Fibrous
membrane
Reflection of
synovial membrane
Neck of femur
Greater
trochanter
Intertrochanteric line
Synovial
membrane
Fibrous
membrane
Lesser
trochanter
A Anterior view
B Posterior view
Fig. 31.11 Ligament of the head of
the femur in the acetabulum
Right hip joint, lateral view.
Acetabular
labrum
Acetabular
roof
Joint
capsule
Acetabular fossa
Obturator
membrane
Acetabular
labrum
Lunate
surface
Fovea on
femoral
head
Lig. of
head of
femur
Greater
trochanter
Lig. of
head of femur
A
The joint capsule has been divided
and the femoral head dislocated
to expose the cut ligament of the
head of the femur.
Lesser
trochanter
Joint
capsule
Acetabular
fossa
Transverse
lig. of
acetabulum
B
Acetabulum of the hip joint. Note: The ligament
of the head of the femur (cut) has no mechanical
function, but transmits branches from the obturator
artery that nourish the femoral head (see p. 473).
417
Lower Limb
Anterior Muscles of the Hip, Thigh & Gluteal Region (I)
Fig. 31.12 Anterior muscles of the hip and thigh (I)
Right limb. Muscle origins are shown in red, insertions in blue.
Anterior
longitudinal
lig.
Iliac crest
Iliacus
Sacral
promontory
Anterior
superior
iliac spine
Psoas major
Piriformis
Sartorius
Inguinal
lig.
Rectus
femoris
Tensor
fasciae latae
Iliopsoas
Pubic
symphysis
Pectineus
Adductor
longus
Rectus
femoris
Sartorius
Gracilis
Vastus
intermedius
Adductor
magnus
Iliotibial
tract
Vastus
medialis
Vastus
lateralis
Sartorius
Quadriceps
femoris tendon
Gracilis
Patella
Head of
fibula
Patellar lig.
Semitendinosus
Pes anserinus
A
Removed: Fascia lata of thigh (to the lateral iliotibial tract).
418
Pes anserinus
(common
tendon of
insertion)
B
Removed: Inguinal ligament, sartorius and rectus femoris.
Iliacus
31 Hip & Thigh
Psoas
major
Psoas
major
Iliacus
Sartorius
Sartorius
Tensor
fasciae latae
Gluteus
medius
Piriformis
Rectus
femoris
Gluteus
minimus
Piriformis
Piriformis
Rectus
femoris
Gluteus
minimus
Piriformis
Iliofemoral
lig.
Obturator
externus
Iliopsoas
Pectineus
Vastus
lateralis
Vastus
medialis
Gluteus
medius
Pectineus
Obturator
externus
Vastus
lateralis
Adductor
brevis
Iliopsoas
Adductor
minimus
Adductor
brevis
Vastus
medialis
Adductor
longus
Adductor
longus
Gracilis
Gracilis
Vastus
intermedius
Vastus
intermedius
Adductor
magnus
Adductor
magnus
Adductor
hiatus
Vastus
lateralis
Articularis
genus
Adductor
hiatus
Articularis
genus
Vastus
medialis
Iliotibial
tract
Iliotibial
tract
Patellar lig.
Pes anserinus
C
Removed: Rectus femoris (completely), vastus lateralis, vastus
­medialis, iliopsoas, and tensor fasciae latae.
Biceps
femoris
Quadriceps
femoris
Semimembranosus
Gracilis
Sartorius
Semitendinosus
Pes anserinus
(common
tendon of
insertion)
DRemoved: Quadriceps femoris (rectus femoris, vastus lateralis, vastus
medialis, vastus intermedius), iliopsoas, tensor fasciae latae, pectineus,
and midportion of adductor longus.
419
Lower Limb
Anterior Muscles of the Hip, Thigh & Gluteal Region (II)
Fig. 31.13 Anterior muscles of the hip and thigh (II)
Right limb. Muscle origins are shown in red, insertions in blue.
Psoas major
Iliacus
Sartorius
Rectus
femoris
Piriformis
Pectineus
Piriformis
Obturator
externus
Gluteus
minimus
Vastus
lateralis
Gracilis
Iliopsoas
Adductor
longus
Adductor
minimus
Adductor
brevis
Quadratus
femoris
Adductor
magnus
Adductor
hiatus
Piriformis
Rectus
femoris
Piriformis
Pectineus
Gluteus
minimus
Gracilis
Adductor
longus
Vastus
lateralis
Adductor
brevis
Iliopsoas
Quadratus
femoris
Vastus
medialis
Adductor
magnus
Obturator
externus
Vastus
intermedius
Articularis
genus
Tendinous
insertion of
adductor magnus
Adductor
magnus
Adductor
tubercle
Semimembranosus
Iliotibial
tract
Semimembranosus
Gracilis
Biceps
femoris
Gracilis
Sartorius
Quadriceps
femoris
A
Removed: Gluteus medius and minimus, piriformis, obturator externus,
adductor brevis and longus, and gracilis.
420
Semitendinosus
B
Removed: All muscles.
Midsagittal section.
L5 vertebral body
Iliac crest
31 Hip & Thigh
Fig. 31.14 Medial muscles of the hip,
thigh, and gluteal region
Sacral promontory
Iliacus
Anterior superior
iliac spine
Sacrum
Psoas minor
Psoas major
Obturator
internus
Piriformis
Sacrospinous lig.
Pubic
symphysis
Gluteus
maximus
Sartorius
Adductor
magnus
Adductor
longus
Rectus
femoris
Semitendinosus
Gracilis
Semimembranosus
Vastus
medialis
Patella
Patellar lig.
Pes anserinus
(common tendon
of insertion)
Gastrocnemius
Tibialis
anterior
Tibia
421
Posterior Muscles of the Hip, Thigh & Gluteal Region (I)
Lower Limb
Fig. 31.15 Posterior muscles of the hip, thigh, and gluteal region (I)
Right limb. Muscle origins are shown in red, insertions in blue.
L5 spinous
process
Gluteus
medius
Iliac crest
Iliac crest
Anterior
superior
iliac spine
Anterior
superior
iliac spine
Gluteus
medius
Tensor
fasciae latae
Gluteus
maximus
Greater
trochanter
Gluteus
minimus
Gluteus
maximus
Tensor
fasciae latae
Gemellus
superior
Piriformis
Gluteus
medius
Gemellus
inferior
Obturator
internus
Quadratus
femoris
Gluteus
maximus
Sacrotuberous
lig.
Adductor
magnus
Ischial
tuberosity
Adductor
magnus
Semitendinosus
Iliotibial
tract
Biceps femoris,
long head
Gracilis
Semimembranosus
Iliotibial
tract
Semitendinosus
Gracilis
Popliteal fossa
Semimembranosus
Plantaris
Plantaris
Pes anserinus
Gastrocnemius, medial
and lateral heads
A
Removed: Fascia lata (to iliotibial tract).
422
Biceps
femoris,
long head
Gastrocnemius, medial
and lateral heads
B
Partially removed: Gluteus maximus and medius.
Tensor
fasciae
latae
Tensor
fasciae
latae
Gluteus
minimus
Gluteus
maximus
Gemellus
superior
Piriformis
Gemellus
inferior
Gluteus
medius
Obturator
internus
Quadratus
femoris
Sacrotuberous
lig.
Vastus
lateralis
Adductor
magnus
Gluteus
maximus
Gluteus
minimus
Gluteus
maximus
Gemellus
superior
Rectus
femoris
Gemellus
inferior
Piriformis
Gluteus
medius and
minimus
Obturator
internus
Quadratus
femoris
Semimembranosus
Biceps femoris
(long head) and
semitendinosus
(cut)
Gluteus
maximus
Adductor
magnus
Adductor
magnus
Vastus
intermedius
Vastus
intermedius
Semimembranosus
Semitendinosus (cut)
Gracilis
31 Hip & Thigh
Gluteus
medius
Gluteus
medius
Biceps
femoris,
short head
Biceps
femoris,
long head
Vastus
lateralis
Adductor
hiatus
Biceps
femoris,
short
head
Plantaris
Plantaris
Gastrocnemius,
medial and
lateral heads
Semimembranosus
Biceps
femoris
Popliteus
Soleus
Gastrocnemius,
medial and
lateral heads
Tibialis
posterior
Flexor digitorum
longus
C
Removed: Semitendinosus and biceps femoris (partially); gluteus
maximus and medius (completely).
DRemoved: Hamstrings (semitendinosus, semimembranosus, and biceps
femoris), gluteus minimus, gastrocnemius, and muscles of the leg.
423
Lower Limb
Posterior Muscles of the Hip, Thigh & Gluteal Region (II)
Fig. 31.16 Posterior muscles of the hip, thigh, and gluteal region (II)
Right limb. Muscle origins are shown in red, insertions in blue.
Gluteus medius
Tensor
fasciae latae
Gluteus
minimus
Gluteus
maximus
Gemellus
superior
Obturator
externus
Gemellus
inferior
Gluteus
medius and
minimus,
piriformis
Obturator
internus
Quadratus
femoris
Iliopsoas
Rectus femoris
Obturator internus
and externus,
gemellus superior
and inferior
Gemellus
superior
Gemellus
inferior
Gluteus
medius and
minimus,
piriformis
Obturator
internus
Quadratus
femoris
Semimembranosus
Biceps femoris,
long head and
semitendinosus
Iliopsoas
Adductor
magnus
Adductor
magnus
Gluteus
maximus
Pectineus
Vastus
lateralis
Adductor
brevis
Adductor
brevis
Vastus
medialis
Adductor
longus
Adductor
magnus
Vastus
intermedius
Adductor
magnus
Adductor
longus
Biceps
femoris,
short head
Vastus
medialis
Adductor
magnus
Adductor
magnus
Plantaris
Gastrocnemius,
medial and
lateral heads
Semimembranosus
Biceps
femoris
Popliteus
Soleus
Tibialis
posterior
Flexor
digitorum longus
A
Removed: Piriformis, obturator internus, quadratus femoris, and
adductor magnus.
424
B
Removed: All muscles.
31 Hip & Thigh
Fig. 31.17 Lateral muscles of the hip, thigh, and gluteal region
Note: The iliotibial tract (the thickened band of fascia lata) functions as a tension band
to reduce the bending loads on the proximal femur.
L4 spinous
process
Posterior superior
iliac spine
Iliac crest
Anterior superior
iliac spine
Gluteus
medius
Tensor
fasciae latae
Gluteus
maximus
Sartorius
Rectus
femoris
Iliotibial tract
Long head
Biceps
femoris
Short head
Vastus
lateralis
Patella
Fibula, head
Fibularis longus
Gastrocnemius
Patellar lig.
Tibial
tuberosity
Tibialis
anterior
425
Lower Limb
Muscle Facts (I)
Iliopsoas muscle
Table 31.1
Muscles
Origin
Insertion
① Psoas major*
Superficial: T12–L4 and associated
intervertebral disks (lateral surfaces)
Deep: L1–L5 vertebrae (costal
processes)
② Iliacus
Iliac fossa
③ Iliopsoas
Femur
(lesser trochanter)
Innervation
Action
Lumbar plexus L1, L2(L3)
Femoral n. (L2–L3)
• Hip joint: flexion and external rotation
• Lumbar spine: unilateral contraction
(with the femur fixed) flexes the trunk
laterally to the same side; bilateral
contraction raises the trunk from the
supine position
* The psoas minor, present in approximately 50% of the population, is often found on the superficial surface of the psoas major (see Fig. 31.19). It is not a muscle of
the lower limb. It originates, inserts, and exerts its action on the abdomen (see Table 13.1, p. 148).
Fig. 31.18 Muscles of the hip
Right side, schematic.
G
F
K
SA
H
J
Ö
Iliotibial
tract
L
Ä
D
A
Iliopsoas muscle,
anterior view.
Table 31.2
426
B
Vertically oriented
gluteal muscles,
posterior view.
C
Horizontally oriented gluteal
muscles, posterior view.
Gluteal muscles
Muscle
Origin
Insertion
Innervation
Action
④ Gluteus maximus
Sacrum (dorsal surface, lateral part),
ilium (gluteal surface, posterior
part), thoracolumbar fascia,
sacrotuberous lig.
• Upper fibers: iliotibial tract
• Lower fibers: gluteal tuberosity
Inferior gluteal
n. (L5–S2)
• Entire muscle: extends and externally
rotates the hip in sagittal and coronal planes
• Upper fibers: abduction
• Lower fibers: adduction
⑤ Gluteus medius
Ilium (gluteal surface below the
iliac crest between the anterior and
posterior gluteal line)
Greater trochanter of the femur
(lateral surface)
⑥ Gluteus minimus
Ilium (gluteal surface below the
origin of gluteus medius)
Greater trochanter of the femur
(anterolateral surface)
⑦ Tensor fasciae latae
Anterior superior iliac spine
Iliotibial tract
⑧ Piriformis
Pelvic surface of the sacrum
Apex of the greater trochanter of
the femur
⑨ Obturator internus
Inner surface of the obturator
membrane and its bony boundaries
Medial surface of the greater
trochanter
⑩ Gemelli
• Gemellus superior: ischial spine
• Gemellus inferior: ischial tuberosity
Jointly with obturator internus
tendon (medial surface, greater
trochanter)
⑪ Quadratus femoris
Lateral border of the ischial tuberosity
Intertrochanteric crest of the femur
Superior gluteal
n. (L4–S1)
• Entire muscle: abducts the hip, stabilizes
the pelvis in the coronal plane
• Anterior part: flexion and internal rotation
• Posterior part: extension and external
rotation
• Tenses the fascia lata
• Hip joint: abduction, flexion, and internal
rotation
Sacral plexus
(S1, S2)
Sacral plexus
(L5, S1)
• External rotation, abduction, and extension
of the hip joint
• Stabilizes the hip joint
External rotation and extension of the hip
joint (also active in abduction, depending on
the joint’s position)
External rotation of the hip joint
Fig. 31.19 Psoas and iliacus muscles
Fig. 31.20 Superficial muscles of the gluteal region
Right side, anterior view.
Right side, posterior view.
Gluteus
medius
Thoracolumbar
fascia
Tensor
fasciae
latae
Gluteus
maximus
Psoas minor
31 Hip & Thigh
Iliac crest
Psoas major
L5 vertebra
Sacral promontory
Axis of abduction/
adduction
Iliac crest
Iliotibial
tract
Iliacus
Anterior
superior
iliac spine
Inguinal lig.
Sacrospinous lig.
Greater
trochanter
Tibia
Fibula
Intertrochanteric
line
Interosseous
membrane
Iliopsoas
Lesser
trochanter
Fig. 31.21 Deep muscles of the gluteal region
Iliac crest
Iliac crest
Ilium, gluteal
surface
Anterior superior
iliac spine
Gluteus medius
Posterior gluteal line
Gluteus minimus
Piriformis
Piriformis
Obturator internus
Gemellus superior
and inferior
Quadratus femoris
Obturator internus
Gemellus superior
and inferior
Quadratus femoris
Ischial spine
Greater trochanter
Greater trochanter
Sacrotuberous lig.
Ischial
tuberosity
A
Deep layer with gluteus maximus removed.
Gluteal tuberosity
Lesser
trochanter
Intertrochanteric
crest
B
Deep layer with gluteus maximus and gluteus medius removed.
427
Lower Limb
Muscle Facts (II)
Functionally, the medial thigh muscles are considered the
adductors of the hip.
Promontory
Iliac crest
Fig. 31.22 Medial thigh muscles: Superficial layer
Right side, anterior view.
Superior
pubic ramus
Greater
trochanter
Lesser
trochanter
Pectineus
A
S
D
Adductor
brevis
Adductor
longus
Femur
Gracilis
F
Patella
A
Schematic.
Gracilis tendon
Tibia
B
Superficial adductor group.
Table 31.3
428
Fibula
Medial thigh muscles: Superficial layer
Muscle
Origin
Insertion
Innervation
Action
① Pectineus
Pecten pubis
Femur (pectineal line and the
proximal linea aspera)
Femoral n.,
obturator n.
(L2, L3)
• Hip joint: adduction, external rotation, and slight
flexion
• Stabilizes the pelvis in the coronal and sagittal planes
② Adductor longus
Superior pubic ramus and
anterior side of the pubic
symphysis
Obturator n.
(L2–L4)
③ Adductor brevis
Inferior pubic ramus
• Hip joint: adduction and flexion (up to 70 degrees);
extension (past 80 degrees of flexion)
• Stabilizes the pelvis in the coronal and sagittal planes
④ Gracilis
Inferior pubic ramus below
the pubic symphysis
Femur (linea aspera, medial lip in
the middle third of the femur)
Tibia (medial border of the
tuberosity, along with the tendons
of sartorius and semitendinosus)
Obturator n.
(L2, L3)
• Hip joint: adduction and flexion
• Knee joint: flexion and internal rotation
Fig. 31.23 Medial thigh muscles: Deep layer
Right side, anterior view.
31 Hip & Thigh
Iliac crest
Superior
pubic ramus
Obturator
externus
Greater
trochanter
A
Lesser
trochanter
S
Femur
S
Adductor
magnus
Adductor hiatus
Adductor
magnus,
tendinous
part
Adductor
tubercle
Patella
A
Schematic.
Tibial
tuberosity
Tibia
Fibula
B
Deep adductor group.
Table 31.4
Medial thigh muscles: Deep layer
Muscle
Origin
Insertion
Innervation
Action
① Obturator externus
Outer surface of the obturator
membrane and its bony
boundaries
Trochanteric fossa of the femur
Obturator n. (L3, L4)
•H
ip joint: adduction and external rotation
•S
tabilizes the pelvis in the sagittal plane
• Deep part (“fleshy insertion”):
medial lip of the linea aspera
• Deep part:
obturator n. (L2–L4)
• Superficial part (“tendinous
insertion”): adductor tubercle
of the femur
• Superficial part:
tibial n. (L4)
② Adductor magnus
Inferior pubic ramus, ischial ramus,
and ischial tuberosity
•H
ip joint: adduction, extension, and
slight flexion (the tendinous insertion is
also active in internal rotation)
•S
tabilizes the pelvis in the coronal and
sagittal planes
429
Lower Limb
Muscle Facts (III)
The anterior and posterior muscles of the thigh can be classified as
extensors and flexors, respectively, with regard to the knee joint.
Fig. 31.24 Anterior thigh muscles
Right side, anterior view.
Anterior superior
iliac spine
Sartorius
Anterior inferior
iliac spine
Acetabular roof
Greater
trochanter
Greater
trochanter
Intertrochanteric
line
S
A
Sartorius
Rectus
femoris
G
Vastus
medialis
Vastus
lateralis
Vastus
medialis
Quadriceps
femoris
tendon
Rectus
femoris
Sartorius
Patella
Lateral
patellar
retinaculum
Patellar lig.
Pes anserinus
Fibula
Medial patellar
retinaculum
Tibial
tuberosity
A
Schematic.
B
Superficial group.
C
Deep group. Removed: Sartorius and rectus femoris.
Anterior thigh muscles
Muscle
Origin
Insertion
Innervation
Action
① Sartorius
Anterior superior iliac spine
Medial to the tibial tuberosity
(together with gracilis and
semitendinosus)
Femoral n.
(L2, L3)
• Hip joint: flexion, abduction,
and external rotation
• Knee joint: flexion and internal
rotation
② Rectus femoris
Anterior inferior iliac spine,
acetabular roof of hip joint
Tibial tuberosity (via patellar lig.)
③ Vastus medialis
Linea aspera (medial lip),
intertrochanteric line (distal part)
④ Vastus lateralis
Linea aspera (lateral lip), greater
trochanter (lateral surface)
Tibial tuberosity via patellar lig.;
patella and tibial tuberosity via
respective medial and lateral
patellar retinacula
⑤ Vastus intermedius
Femoral shaft (anterior side)
Tibial tuberosity (via patellar lig.)
Articularis genus
(distal fibers of vastus
intermedius)
Anterior side of femoral shaft at
level of the suprapatellar recess
Suprapatellar recess of knee joint
capsule
Quadriceps
femoris*
*The entire muscle inserts on the tibial tuberosity via the patellar lig.
430
Quadriceps
femoris
D
F
Table 31.5
Rectus
femoris
Vastus
intermedius
Vastus
lateralis
Lesser
trochanter
• Hip joint: flexion
• Knee joint: extension
Femoral n.
(L2–L4)
Knee joint: extension
Knee joint: extension; retracts the
suprapatellar bursa to prevent
entrapment of capsule
Right side, posterior view.
Anterior superior
iliac spine
Posterior superior
iliac spine
Posterior inferior
iliac spine
Ischial spine
Sacrotuberous
lig.
Ischial
tuberosity
Gluteal tuberosity
Common
head
S
D
Biceps femoris,
short head
Semitendinosus
Biceps femoris,
long head
Linea aspera
Biceps femoris,
short head
Semitendinosus
A
Biceps femoris,
long head
Semimembranosus
Popliteus
A
Schematic.
Semimembranosus
Semimembranosus
tendon (part)
Fibula, head
Popliteus
Pes anserinus
Medial tibial
condyle
Popliteus
Interosseous
membrane
B
Superficial group.
Table 31.6
31 Hip & Thigh
Fig. 31.25 Posterior thigh muscles
C
Deep group. Removed: Biceps femoris
(long head) and semitendinosus.
Posterior thigh muscles
Muscle
Origin
① Biceps femoris
Long head: ischial tuberosity,
sacrotuberous lig. (common head with
semitendinosus)
Insertion
Innervation
Action
Tibial n. (L5–S2)
• Hip joint (long head): extends
the hip, stabilizes the pelvis in
the sagittal plane
• Knee joint: flexion and external
rotation
Common fibular n.
(L5–S2)
Knee joint: flexion and external
rotation
Tibial n. (L5–S2)
• Hip joint: extends the hip,
stabilizes the pelvis in the
sagittal plane
• Knee joint: flexion and internal
rotation
Head of fibula
Short head: lateral lip of the linea
aspera in the middle third of the femur
② Semimembranosus
Ischial tuberosity
Medial tibial condyle, oblique
popliteal lig., popliteus fascia
③ Semitendinosus
Ischial tuberosity and sacrotuberous
lig. (common head with long head of
biceps femoris)
Medial to the tibial tuberosity in
the pes anserinus (along with the
tendons of gracilis and sartorius)
See p. 451 for the popliteus.
431
32
Knee & Leg
Lower Limb
Tibia & Fibula
The tibia and fibula articulate at two joints, allowing limited motion
(rotation). The crural interosseous membrane is a sheet of tough
connective tissue that serves as an origin for several muscles in the leg.
It also acts with the tibiofibular syndesmosis to stabilize the ankle joint.
Fig. 32.1 Tibia and fibula
Right leg.
Lateral condyle
Tibial plateau
Tibial plateau
Tibiofibular
joint
Medial
condyle
Head of fibula
Tibiofibular
joint
Medial
condyle
Head of fibula
Intercondylar
eminence
Neck of fibula
Tibial
tuberosity
Neck of fibula
Head of tibia
Soleal line
Interosseous
membrane
Interosseous
membrane
Fibula,
shaft
Medial
surface
Lateral
surface
Tibiofibular
syndesmosis
Lateral
malleolus
A
Anterior view.
432
Lateral condyle
Tibia,
shaft
Tibia,
shaft
Lateral
surface
Fibula,
shaft
Medial
surface
Posterior
surface
Anterior
border
Medial
malleolus
Ankle
mortise
Malleolar groove
(for tibialis
posterior tendon)
Medial
malleolus
B
Posterior view.
Lateral
malleolar fossa
Lateral
malleolus
Clinical box 32.1
Head of
fibula
Fibular fracture
Posterior intercondylar area
When diagnosing a fibular fracture, it
is important to determine whether the
tibiofibular syndesmosis (see p. 432) is
disrupted. Fibular fractures may occur distal
to, level with, or proximal to the tibiofibular
syndesmosis; the latter two frequently
involve tearing of the syndesmosis.
32 Knee & Leg
Intercondylar
eminence
Fibula
Tibia
Medial
malleolus
Tibiofibular
syndesmosis
Lateral
malleolus
Talus
Calcaneus
Lateral
condyle
Tibial
tuberosity
Medial
condyle
Anterior
intercondylar
area
C
Proximal view.
Posterior
surface
Posterior
surface
Interosseous
membrane
Tibia
Lateral
surface
Fibula
In this fracture located proximal to the
syndesmosis (arrow), the syndesmosis is
torn, as indicated by the widened medial
joint space of the upper ankle joint (see
pp. 456–457).
Medial
surface
Medial
surface
Lateral
surface
Anterior
border
DTransverse section, proximal view.
Articular surface
of lateral malleolus
Inferior
articular surface
Articular surface of
medial malleolus
Fibula
Lateral
malleolus
Medial
malleolus
Lateral
malleolar fossa
Tibia
Distal view.
E
433
Lower Limb
Knee Joint: Overview
In the knee joint, the femur articulates with the tibia and patella. Both
joints are contained within a common capsule and have communicating articular cavities. Note: The fibula is not included in the knee joint
(contrast to the humerus in the elbow; see p. 326). Instead, it forms a
separate rigid articulation with the tibia.
Fig. 32.2 Right knee joint
Femur
Popliteal
surface
Intercondylar
notch
Patella
Lateral
epicondyle
Medial
epicondyle
Lateral
epicondyle
Lateral femoral
condyle
Medial femoral
condyle
Lateral femoral
condyle
Lateral tibial
condyle
Intercondylar
eminence
Medial
tibial condyle
Tibial plateau
Tibiofibular
joint
Head of fibula
Head of fibula
Neck of fibula
Tibial
tuberosity
Soleal line
Fibula
Fibula
Tibia
A
Anterior view.
434
Tibia
B
Posterior view.
Fig. 32.3 Patella
Base
32 Knee & Leg
Apex
Anterior
surface
A
Anterior view.
Articular
surface
Femoropatellar
joint
Apex
B
Posterior view.
Lateral
femoral
condyle
Patella
Fig. 32.4 Patellofemoral joint:
Transverse section
Lateral
tibial
condyle
Head of
fibula
Distal view with right knee in slight flexion.
Patellar lig.
(quadriceps tendon)
Prepatellar
bursa
Medial facet
Tibial
tuberosity
Fibula
Patella
Lateral facet
Radiographic
view in
Fig. 35.11B
Joint space
Tibia
Patellar surface
of femur
Fibrous
membrane
C
Lateral view.
Lateral collateral
lig.
Lateral femoral
condyle
Common
fibular n.
Synovial
membrane
Medial
collateral
lig.
Cruciate
ligs.
Medial
femoral
condyle
Popliteal a. and v.
Tibial n.
Gastrocnemius
435
Lower Limb
Knee Joint: Capsule, Ligaments & Bursae
Table 32.1
Ligaments of the
knee joint
Fig. 32.5 Ligaments of the knee joint
Extrinsic ligaments
Anterior view of right knee.
Patellar lig.
Medial longitudinal patellar
retinaculum
Anterior side
Lateral longitudinal patellar
retinaculum
Femur
Medial transverse patellar
retinaculum
Lateral transverse patellar
retinaculum
Medial and lateral
sides
Posterior side
Medial (tibial) collateral lig.
Vastus
intermedius
tendon of
insertion
Lateral (fibular) collateral
lig.
Oblique popliteal lig.
Arcuate popliteal lig.
Vastus
lateralis
Vastus
medialis
Intrinsic ligaments
Anterior cruciate lig.
Posterior cruciate lig.
Rectus femoris
tendon of
insertion
Transverse lig. of knee
Posterior meniscofemoral lig.
Lateral transverse
patellar retinaculum
Medial collateral
lig.
Lateral longitudinal
patellar retinaculum
Medial
transverse
patellar
retinaculum
Lateral collateral lig.
Medial
longitudinal
patellar
retinaculum
Head of fibula
Patellar lig.
Tibial
tuberosity
Fibula
Tibia
Interosseous
membrane
436
Posterior view of right knee. The joint cavity communicates with periarticular bursae at the subpopliteal recess, semimembranosus bursa,
and medial subtendinous bursa of the gastrocnemius.
Clinical box 32.2
Gastrocnemio-semimembranosus bursa
(Baker’s cyst)
Painful swelling behind the knee may be caused by
a cystic outpouching of the joint capsule (synovial
popliteal cyst). This frequently results from an increase
in intra-articular pressure (e.g., in rheumatoid arthritis).
32 Knee & Leg
Fig. 32.6 Capsule, ligaments, and periarticular bursae
Femur
Medial
subtendinous
bursa of
gastrocnemius
Lateral
subtendinous
bursa of
gastrocnemius
Oblique
popliteal lig.
Semimembranosus
bursa
Lateral
collateral lig.
Medial
collateral
lig.
Arcuate
popliteal lig.
Axial MRI of a Baker’s cyst in the right popliteal fossa,
inferior view. Baker’s cysts often occur in the medial
part of the popliteal fossa between the semimem­
branosus tendon and the medial head of the gas­
trocnemius at the level of the posteromedial femoral
condyle.
Popliteus
Subpopliteal
recess
Fibula
Tibia
437
Lower Limb
Knee Joint: Ligaments & Menisci
Fig. 32.7 Collateral and patellar ligaments of the knee joint
Right knee joint. Each knee joint has medial and lateral collateral ligaments. The medial collateral ligament is attached to both the capsule
and the medial meniscus, whereas the lateral collateral ligament has no
direct contact with either the capsule or the lateral meniscus. Both
collateral ligaments are taut when the knee is in extension and stabilize
the joint in the coronal plane.
Femur
Quadriceps
femoris tendon
Femoropatellar
joint
Femur
Medial epicondyle
Quadriceps femoris
tendon
Medial femoral
condyle
Medial meniscus
Patellar
lig.
Medial
collateral lig.
Patella
Lateral
epicondyle
Lateral femoral
condyle
Fibula
Tibia,
medial
surface
Lateral collateral lig.
Posterior lig. of
fibular head
Patellar
surface
of femur
Lateral
meniscus
Patellar
lig.
Anterior
lig. of
fibular
head
A
Medial view.
Tibial
tuberosity
Fibula
B
Lateral view.
438
Fig. 32.8 Menisci in the knee joint
Right tibial plateau, proximal view.
Medial
meniscus
Injury to the menisci
Transverse lig.
of knee
The less mobile medial meniscus (see Fig.
32.9) is more susceptible to injury than the
lateral meniscus. Trauma generally results
from sudden extension or rotation of the
flexed knee while the leg is fixed.
32 Knee & Leg
Clinical box 32.3
Patellar lig.
Anterior cruciate lig.
Tibiofibular
joint
Medial
collateral lig.
Lateral
collateral lig.
Posterior
cruciate lig.
Posterior meniscofemoral lig.
Lateral
meniscus
Head of
fibula
A
Bucket-handle tear.
A
Right tibial plateau with cruciate, patellar,
and collateral ligaments divided.
Medial meniscus
Anterior cruciate lig.
Synovial
membrane
B
Attachment sites of menisci and cruciate
ligaments. Red line indicates the tibial
attachment of the synovial membrane
that covers the cruciate ligaments. The
cruciate ligaments lie in the subsynovial
connective tissue.
Radial tear of posterior horn.
B
Head of
fibula
Posterior cruciate lig.
Lateral meniscus
Fig. 32.9 Movements of the menisci
Right knee joint. The medial meniscus, which is
anchored more securely than the lateral meniscus,
undergoes less displacement during knee flexion.
Patella
Patella
Extension
Patellar
Patellar
lig. ligament
Lateral
Lateral
collateral
collateral
lig. ligament
Flexion
A
Extension.
Medial
collateral
Medial
collateral
ligament
ligament
B
Flexion.
Lateral
collateral
Lateral
collateral
ligament
ligament
C
Tibial plateau, proximal view.
439
Lower Limb
Cruciate Ligaments
Fig. 32.10 Cruciate and collateral ligaments
Right knee joint. The cruciate ligaments keep the articular surfaces of
the femur and tibia in contact, while stabilizing the knee joint primarily
in the sagittal plane. Portions of the cruciate ligaments are taut in every
joint position.
Intercondylar
notch
Patellar
surface
of femur
Medial
femoral
condyle
Anterior
cruciate lig.
Transverse
lig. of knee
Anterior
cruciate lig.
Posterior
meniscofemoral lig.
Lateral
meniscus
Posterior
cruciate lig.
Medial
meniscus
Lateral
meniscus
Lateral
collateral lig.
Medial
collateral lig.
Lateral
collateral lig.
Anterior lig.
of fibular head
Lateral femoral
condyle
Posterior lig. of
fibular head
Patellar lig.
(reflected
inferiorly)
Head of fibula
Patella
Fibula
Tibia
A
Anterior view.
440
B
Posterior view.
Interosseous
membrane
Fig. 32.11 Right knee joint in flexion
Clinical box 32.4
Anterior view with joint capsule and patella removed.
Patellar surface
of femur
Posterior
cruciate lig.
Medial femoral
condyle
Lateral femoral
condyle
Lateral
collateral lig.
Anterior
cruciate lig.
Cruciate ligament rupture destabilizes
the knee joint, allowing the tibia to
move forward (anterior “drawer sign”) or
backward (posterior “drawer sign”) relative
to the femur. Anterior cruciate ligament
ruptures are approximately 10 times more
common than posterior ligament ruptures.
The most common mechanism of injury
is an internal rotation trauma with the leg
fixed. A lateral blow to the fully extended
knee with the foot planted tends to cause
concomitant rupture of the anterior cruciate
and medial collateral ligaments, as well as
tearing of the attached medial meniscus.
32 Knee & Leg
Rupture of cruciate ligaments
Medial
meniscus
Lateral
meniscus
Head of fibula
Medial collateral lig.
Tibial
tuberosity
Fibula
Tibia
Right knee in flexion, rupture of anterior
A
cruciate ligament, anterior view.
Fig. 32.12 Cruciate and collateral ligaments in flexion and extension
Right knee, anterior view. Taut ligament fibers shown in red. While most parts of the
collateral ligaments are taut only in extension (A), the cruciate ligaments, or portions of
them, are taut in flexion, extension and internal rotation (B,C). The cruciate ligaments
thus help stabilize the knee in any joint position.
A
Extension.
Flexion.
B
B
Right knee in flexion, anterior “drawer
sign,” medial view. During examination
of the flexed knee, the tibia can be pulled
forward.
Flexion and internal rotation.
C
441
Lower Limb
Knee Joint Cavity
Fig. 32.13 Opened joint capsule
Fig. 32.14 Joint cavity
Right knee, anterior view with patella reflected downward.
Right knee, lateral view. The joint cavity was demonstrated by injecting
liquid plastic into the knee joint and later removing the capsule.
Quadriceps tendon
Suprapatellar
pouch
Femur
Femur
Suprapatellar
pouch
Patella
Femur,
patellar
surface
Lateral
femoral
condyle
Anterior
cruciate lig.
Medial
femoral
condyle
Lateral
collateral lig.
Lateral
meniscus
Lateral collateral
lig.
Patellar lig.
Subpopliteal
recess
Infrapatellar
bursa
Medial
meniscus
Alar folds
Lateral
meniscus
Fibula
Tibia
Infrapatellar
fat pad
Patella,
articular
surface
Joint capsule
(cut edge)
Suprapatellar
pouch
Fibula
Tibia
Fig 32.15 Relations of structures to the joint capsule and
articular cavity
Right knee joint, proximal view.
Several joint structures provide strength or stability to the knee from
outside of, or within, the joint space.
• Extracapsular structures (lateral collateral ligament) remain outside
of the joint capsule.
• Intracapsular structures (medial collateral and cruciate ligaments) lie
within the joint capsule but run in the subsynovial tissue outside the
synovial membrane and are therefore also extra-articular.
• Intra-articular structures (menici) lie within the articular cavity, enclosed by the synovial membrane, and are bathed in synovial fluid.
Patellar lig.
Intracapsular
ligs.
Cruciate ligs.
Medial (tibial)
collateral lig.
Medial
meniscus
442
Fibrous membrane
Subintima Synovial
Intima membrane
Lateral
meniscus
Extracapsular lig.
(lateral [fibular]
collateral lig.)
Fibula
Joint
capsule
Fig. 32.17 Suprapatellar pouch
during flexion
Lateral view.
Right knee joint, medial view.
Suprapatellar
pouch
Femur
32 Knee & Leg
Fig. 32.16 Right knee joint: Midsagittal section
Sites of
attachment
of the joint
capsule
Suprapatellar
pouch
A
Neutral
(0-degree)
position.
Quadriceps
tendon
Patella
Quadriceps
femoris
Prepatellar
bursa
Patellar lig.
Patella
Infrapatellar
fat pad
Patellar
lig.
Anterior intercondylar area
Infrapatellar
bursa
B 80 degrees
of flexion.
Tibia
Anterior
cruciate lig.
C 130 degrees
of flexion.
Clinical box 32.5
The ballottable patella sign of
knee effusion
Intra-articular effusion due to
inflammatory changes or injury can
be differentiated from swelling of
the joint capsule by pushing down
on the patella of the extended knee.
If there is excessive fluid in the
joint, the patella will rebound when
released, signifying a positive test.
Patella
Effusion
Femur Effusion Tibia Fibula
443
Lower Limb
Muscles of the Leg: Anterior & Lateral Compartments
Fig. 32.18 Muscles of the anterior compartment of the leg
Right leg. Muscle origins shown in red, insertions in blue.
Rectus
femoris
Femur
Gracilis
Vastus
lateralis
Sartorius
Iliotibial
tract
Vastus
medialis
Patella
Head of fibula
Fibularis
longus
Tibial
tuberosity
Patellar lig.
Tibial
tuberosity
Pes anserinus
(common tendon
of insertion of
sartorius, gracilis,
and semitendinosus)
Gastrocnemius,
medial head
Fibularis
longus
Tibialis
anterior
Extensor
digitorum longus
Soleus
Tibia
Extensor
hallucis longus
Tibialis
anterior
Extensor
digitorum longus
Extensor
hallucis longus
Fibularis
brevis
Medial
malleolus
Fibularis tertius
(variable)
Extensor
hallucis brevis
Interossei
Extensor
digitorum brevis
Fibularis
tertius
Extensor
hallucis brevis
Tibialis
anterior
Extensor
digitorum longus
Extensor
hallucis longus
A
All muscles shown.
444
Extensor
digitorum longus
B
Removed: Tibialis anterior and fibularis longus; extensor digitorum
longus tendons (distal portions). Note: The fibularis tertius is a division of the extensor digitorum longus.
Right leg. The triceps surae is comprised of the soleus and two heads of
the gastrocnemius.
Biceps
femoris,
long head
Patella
Rectus
femoris
32 Knee & Leg
Fig. 32.19 Muscles of the lateral compartment of the leg
Vastus
lateralis
Biceps femoris,
short head
Iliotibial
tract
Patella
Biceps femoris,
common tendon
of insertion
Fibularis
longus
Interosseous
membrane
Patellar lig.
Head of fibula
Lateral
tibial condyle
Gastrocnemius,
lateral head
Tibialis
anterior
Fibularis
longus
Extensor
digitorum longus
Tibialis
anterior
Soleus
Extensor
hallucis longus
Extensor
digitorum longus
Triceps
surae
Fibularis
brevis
Fibularis
tertius
Fibularis
brevis
Extensor
digitorum brevis
Lateral
malleolus, fibula
Extensor hallucis
brevis and
extensor
digitorum brevis
Fibularis tertius
(variable)
Calcaneal
(Achilles’) tendon
Fibularis
brevis
Tibialis
anterior
Fibularis
tertius
Extensor
hallucis brevis
Extensor
digitorum
longus
Extensor
hallucis longus
Extensor
digitorum brevis
Calcaneus
Fibularis
longus
Fibularis
brevis
Extensor
digitorum longus
Extensor
hallucis longus
C
Removed: All muscles.
445
Lower Limb
Muscles of the Leg: Posterior Compartment
Fig. 32.20 Muscles of the posterior compartment of the leg
Right leg. Muscle origins shown in red, insertions in blue.
Gracilis
Semitendinosus
Iliotibial
tract
Semimembranosus
Plantaris
Gastrocnemius,
medial head
Plantaris
Biceps
femoris
Gastrocnemius,
medial head
Gastrocnemius,
lateral head
Biceps femoris
Popliteus
Gastrocnemius,
lateral head
Fibularis
longus
Soleus
Plantaris
tendon
Fibularis longus
Fibularis
longus
Flexor
digitorum longus
Calcaneal
(Achilles’) tendon
Medial
malleolus
Tibialis
posterior
Flexor
digitorum longus
Soleus
Flexor
hallucis longus
Lateral
malleolus
Calcaneus
Fibularis
brevis
Fibularis
longus
A
Note: The bulge of the calf is produced mainly by the triceps surae
(soleus and the two heads of the gastrocnemius).
Calcaneal
(Achilles’) tendon
Flexor
hallucis longus
Fibularis brevis
Fibularis
brevis
Flexor
hallucis longus
446
Flexor
digitorum longus
Tibialis
posterior
Flexor
digitorum longus
Flexor
hallucis longus
B
Removed: Gastrocnemius (both heads).
Calcaneus
Fibularis
brevis
Fibularis
longus
Gastrocnemius,
lateral head
Plantaris
Gastrocnemius,
medial head
Gastrocnemius,
lateral head
Popliteus
Popliteus
Biceps femoris
Biceps femoris
Fibularis
longus
Fibularis
longus
Soleus
32 Knee & Leg
Plantaris
Gastrocnemius,
medial head
Soleus
Tibialis
posterior
Tibialis
posterior
Flexor
digitorum longus
Flexor
digitorum longus
Flexor
hallucis longus
Flexor
hallucis longus
Interosseous
membrane
Fibularis
brevis
Crural chiasm
(intersection of
two tendons)
Plantaris
Triceps
surae
Plantaris
Triceps
surae
Tibialis
posterior
Fibularis
brevis
Tibialis
anterior
Fibularis
longus
Plantar chiasm
(intersection of
two tendons)
Tibialis
posterior
Fibularis
brevis
Tibialis
anterior
Flexor
hallucis longus
Flexor
digitorum longus
Flexor
hallucis longus
Flexor
digitorum longus
C
Removed: Triceps surae, plantaris, popliteus, fibularis
longus, and fibularis brevis muscles.
DRemoved: All muscles.
447
Lower Limb
Muscle Facts (I)
he muscles of the leg control the flexion/extension and inversion/
T
eversion of the foot, which provide stability to the lower limb during
movements at the knee and hip joint.
Femur
Fig. 32.21 Muscles of the lateral compartment
of the leg
Right leg and foot.
Patella
Lateral
tibial
condyle
Head of
fibula
Lateral tibial
surface
1st metatarsal
Interosseous
membrane
Medial
cuneiform
Cuboid
①
Fibularis
longus
tendon
②
Fibularis
longus
Course of the fibularis longus tendon,
C
plantar view.
Fibularis
brevis
Fibularis muscles, anterior view, schematic.
A
Lateral
malleolus
Calcaneus
Lateral compartment, right lateral view.
B
Table 32.2
448
Fibularis
longus
tendon
Cuboid
Fibularis
brevis
tendon
Tuberosity
of 5th
metatarsal
Lateral compartment
Muscle
Origin
Insertion
① Fibularis
longus
Fibula (head and proximal two thirds of the
lateral surface, arising partly from the
intermuscular septa)
Medial cuneiform (plantar side),
1st metatarsal (base)
② Fibularis
brevis
Fibula (distal half of the lateral surface),
intermuscular septa
5th metatarsal (tuberosity at the
base, with an occasional division to
the dorsal aponeurosis of the 5th toe)
Innervation
Superficial
fibular n.
(L5, S1)
Action
• Talocrural joint: plantar flexion
• Subtalar joint: eversion (pronation)
• Supports the transverse arch of the foot
• Talocrural joint: plantar flexion
• Subtalar joint: eversion (pronation)
Fig. 32.22 Muscles of the anterior compartment of the leg
Right leg, anterior view.
Femur
32 Knee & Leg
Lateral
epicondyle
Lateral
tibial
condyle
Head of
fibula
Tibial
tuberosity
1
3
2
Shaft of tibia
Tibialis
anterior
4
A
Schematic.
Table 32.3
B
Anterior compartment.
Extensor
digitorum
longus
Anterior compartment
Muscle
Origin
Insertion
Innervation
Action
① Tibialis
anterior
Tibia (upper two
thirds of the lateral
surface), interosseous
membrane, and
superficial crural fascia
(highest part)
Medial cuneiform
(medial and
plantar surface),
first metatarsal
(medial base)
Deep fibular
n. (L4, L5)
• Talocrural joint: dorsiflexion
• Subtalar joint: inversion
(supination)
Deep fibular
n. (L4, L5)
• Talocrural joint: dorsiflexion
• Subtalar joint: active in
both eversion and inversion
(pronation/supination),
depending on the initial
position of the foot
• Extends the MTP and IP
joints of the big toe
2nd to 5th toes
(at the dorsal
aponeuroses at
the bases of the
distal phalanges)
Deep fibular
n. (L4, L5)
• Talocrural joint: dorsiflexion
• Subtalar joint: eversion
(pronation)
• Extends the MTP and IP
joints of the 2nd to 5th toes
5th metatarsal
(base)
Deep fibular
n. (L4, L5)
• Talocrural joint: dorsiflexion
• Subtalar joint: eversion
(pronation)
② Extensor
hallucis
longus
Fibula (middle
third of the medial
surface), interosseous
membrane
1st toe (at
the dorsal
aponeurosis at
the base of its
distal phalanx)
③ Extensor
digitorum
longus
Fibula (head and
medial surface), tibia
(lateral condyle),
and interosseous
membrane
④ Fibularis
tertius
Distal fibula
(anterior border)
Extensor
hallucis
longus
Fibularis
tertius
Lateral
malleolus
Fibularis
tertius
tendon
Medial
malleolus
Extensor
digitorum
longus
tendon
Extensor
hallucis
longus
tendon
1st through 5th
distal phalanges
IP, interphalangeal; MTP, metatarsophalangeal.
449
Lower Limb
Muscle Facts (II)
Fig. 32.23 Muscles of the posterior compartment
of the leg: Superficial flexors
The muscles of the posterior compartment are divided into two groups:
the superficial and deep flexors. These groups are separated by the
transverse intermuscular septum.
Right leg, posterior view.
Femur
③
Medial
epicondyle
①
Lateral
epicondyle
Plantaris
Gastrocnemius,
lateral head (cut)
Plantaris
Medial femoral
condyle
②
Gastrocnemius,
medial head
(cut)
Medial tibial
condyle
Head of fibula
Tendinous
arch of
soleus
Plantaris
tendon
Gastrocnemius,
lateral head
A
Foot in plantar
flexion, schematic.
Triceps
surae
Soleus
Gastrocnemius,
medial head
Gastrocnemius,
medial head
Triceps
surae
Gastrocnemius,
lateral head
Soleus
Plantaris
tendon
Calcaneal
(Achilles’)
tendon
Medial
malleolus
Lateral
malleolus
Talus
Navicular
1st metatarsal
450
Talus
Subtalar
joint
Calcaneus
C
Superficial flexors with gastrocnemius
removed (portions of medial and lateral
heads).
Superficial flexors of the posterior compartment
Muscle
Origin
①G
astrocnemius
Triceps surae
Femur (medial head: superior posterior
part of the medial femoral condyle.
lateral head: lateral surface of lateral
femoral condyle)
② Soleus
Fibula (head and neck, posterior surface),
tibia (soleal line via a tendinous arch)
③ Plantaris
Calcaneal
(Achilles’)
tendon
Calcaneal
tuberosity
B
Superficial flexors.
Table 32.4
Talocrural
joint
Femur (lateral epicondyle, proximal to
lateral head of gastrocnemius)
Insertion
Calcaneal
tuberosity via
the calcaneal
(Achilles’) tendon
Calcaneal
tuberosity
Innervation
Action
Tibial n.
(S1, S2)
• Talocrural joint: plantar flexion when knee is
extended (gastrocnemius)
• Knee joint: flexion (gastrocnemius)
• Talocrural joint: plantar flexion (soleus)
Negligible; may act with gastrocnemius in
plantar flexion
Fig. 32.24 Posterior compartment of the leg:
Deep flexors
Right leg with foot in plantar flexion, posterior view.
F
Popliteus
Medial tibial
condyle
Head
of fibula
A
Medial tibial
condyle
Head
of fibula
Soleal line
32 Knee & Leg
Femur
S
D
Tibialis
posterior
Crural
chiasm
Flexor
digitorum
longus
Plantar
chiasm
Tibialis
posterior
Posterior
surface of tibia
Flexor
hallucis
longus
Posterior
surface
of fibula
A
Schematic.
Tibialis
posterior
Interosseous
membrane
Fibula
Calcaneal
tuberosity
Lateral
malleolus
Tuberosity
of cuboid
Talus
Tibialis posterior
tendon
Tuberosity
of 5th
metatarsal
Medial
cuneiform
Medial
malleolus
Table 32.5
Calcaneus
Lateral
malleolus
Tibialis
posterior
tendon
Tibialis
posterior
tendons
Flexor
hallucis
longus
tendon
DInsertion of the tibialis posterior.
Medial
malleolus
Calcaneal
tuberosity
Tuberosity
of 5th
metatarsal
1st through
5th metatarsals
Flexor
digitorum
longus
tendons
B
Deep flexors.
C
Tibialis posterior.
Deep flexors of the posterior compartment
Muscle
Origin
Insertion
Innervation
Action
① Tibialis
posterior
Interosseous membrane, adjacent
borders of tibia and fibula
Navicular tuberosity; cuneiforms
(medial, intermediate, and lateral);
2nd to 4th metatarsals (bases)
Tibial n.
(L4, L5)
• Talocrural joint: plantar flexion
• Subtalar joint: inversion (supination)
• Supports the longitudinal and transverse arches
② Flexor
digitorum
longus
Tibia (middle third of posterior
surface)
2nd to 5th distal phalanges
(bases)
③ Flexor
hallucis
longus
Fibula (distal two thirds of posterior
surface), adjacent interosseous
membrane
1st distal phalanx (base)
④ Popliteus
Lateral femoral condyle, posterior
horn of the lateral meniscus
Posterior tibial surface (above the
origin at the soleus)
Tibial n.
(L5–S2)
Tibial n.
(L4–S1)
• Talocrural joint: plantar flexion
• Subtalar joint: inversion (supination)
• MTP and IP joints of the 2nd to 5th toes: plantar flexion
• Talocrural joint: plantar flexion
• Subtalar joint: inversion (supination)
• MTP and IP joints of the 1st toe: plantar flexion
• Supports the medial longitudinal arch
Knee joint: flexes and unlocks the knee by externally
rotating the femur on the fixed tibia
IP, interphalangeal; MTP, metatarsophalangeal.
451
33
Ankle & Foot
Lower Limb
Bones of the Foot
Fig. 33.1 Subdivisions of the
pedal skeleton
Fig. 33.2 Bones of the foot
Right foot, dorsal view. Descriptive anatomy
divides the skeletal elements of the foot into
the tarsus, metatarsus, and forefoot (ante­
tarsus). Functional and clinical criteria divide
the pedal skeleton into hindfoot, midfoot,
and forefoot.
1st distal phalanx
Head
1st proximal
phalanx
Antetarsus
(phalanges)
Forefoot
1st metatarsal
Metatarsus
(metatarsal bones)
Shaft
5th distal
phalanx
Base
5th middle
phalanx
Head
5th proximal
phalanx
Shaft
5th metatarsal
Base
Midfoot
Medial
cuneiform
Tarsus
(tarsal bones)
Intermediate
cuneiform
Hindfoot
Lateral
cuneiform
Navicular
Tuberosity of
5th metatarsal
Head
Talus
Cuboid
Neck
Body
Calcaneus
Talus
Neck
Body
Head
Posterior process
Intermediate
cuneiform
Navicular
Medial
cuneiform
Calcaneus
Calcaneal
tuberosity
Lateral process of
calcaneal tuberosity
Right foot, lateral view.
B
452
Calcaneal
tuberosity
A
Right foot, dorsal (superior) view.
1st metatarsal
Cuboid
Medial process of
calcaneal tuberosity
Lateral
cuneiform
Tuberosity of
5th metatarsal
5th
metatarsal
5th proximal
phalanx
5th middle
phalanx
5th distal
phalanx
33 Ankle & Foot
1st distal
phalanx
5th distal phalanx
1st proximal
phalanx
5th middle phalanx
Sesamoids
5th proximal phalanx
Clinical box 33.1
The functional position of the foot
Right foot, lateral view. In the neutral (0°)
position, the skeleton of the foot is angled
approximately 90° relative to the skeleton
of the leg. This plantigrade foot position is
termed the “functional position” and is an
important basis for normal standing and
walking.
1st
metatarsal
5th metatarsal
Medial
cuneiform
Intermediate
cuneiform
Tuberosity of
5th metatarsal
Lateral
cuneiform
Groove for
fibularis
longus tendon
Navicular
Tuberosity
of cuboid
Head
Cuboid
Neck
Body
Talus
Calcaneus
Posterior
process
Sustentaculum
tali
C
Right foot, plantar
(inferior) view.
Talus
Neck
Head
Navicular
1st
metatarsal
1st
proximal phalanx
Head
Shaft
Base
Body
Medial
tubercle
Base
Lateral
tubercle
Shaft
Head
Posterior
process
of talus
Calcaneal
tuberosity
Medial
cuneiform
1st distal phalanx
DRight foot, medial view.
Cuboid
Sustentac­
ulum tali
Medial process of
calcaneal tuberosity
453
Joints of the Foot (I)
Lower Limb
Fig. 33.3 Joints of the foot
Right foot with talocrural joint in plantar
flexion.
Talocrural (ankle)
joint
Subtalar
(talocalcaneal) joint
Tranverse
tarsal
joint
Talonavicular joint
Calcaneocuboid joint
Intercuneiform joints
Cuneocuboid joint
Cuneonavicular joint
Tarsometatarsal
joints
Intermetatarsal joints
Metatarsophalangeal
joints
Interphalangeal joint
of the hallux
Proximal
interphalangeal
joints
Distal
interphalangeal
joints
A
Anterior view.
Fibula
Lateral
malleolus
Interosseous
talocalcanean
ligament
Calcaneus
Transverse
tarsal joint
Talonavicular
joint
Calcaneo­
cuboid joint
Cuboid
Intercuneiform
joints
Tarsometatarsal joints
(Lisfranc’s joint line)
Abductor
digiti minimi
Interossei
Tibia
Talocrural (ankle)
joint
Medial
malleolus
Talus
Navicular
Cuneonavicular
joint
Intermediate
cuneiform
Lateral
cuneiform
Medial
cuneiform
Abductor
hallucis
1st metatarsal
Proximal inter­
phalangeal joints
5th middle phalanx
Distal inter­
phalangeal joints
1st metatarso­
phalangeal joint
1st proximal
phalanx
1st distal
phalanx
B
Superior view of coronal section.
454
Fig. 33.4 Proximal articular surfaces
Fig. 33.5 Distal articular surfaces
Right foot, proximal view.
Right foot, distal view.
C
B
Medial malleolar
surface
Lateral
malleolar
surface
Head of talus (with
articular surface
for navicular)
A
Metatarsophalangeal joints.
C
Sustentaculum
tali
33 Ankle & Foot
B
D
A
Superior trochlear
surface of talus
Base of 1st
proximal
phalanx
A
D
Calcaneus
1st through
5th metatarsals
Calcaneus (with articular
surface for cuboid)
Talus
A
Talonavicular and
calcaneocuboid joints.
Navicular
Base of 5th
metatarsal
Base of 1st
metatarsal
Tuberosity of
5th metatarsal
Navicular tuberosity
Calcaneus
B
Tarsometatarsal joints.
B
Cuneonavicular and
calcaneocuboid joints.
Intermediate
Lateral
cuneiform cuneiform
Calcaneus (with
articular surface for cuboid)
Talus Navicular
Intermediate
cuneiform
Cuboid
Medial
cuneiform
Cuboid
Medial
cuneiform
Tuberosity of
5th metatarsal
Lateral
cuneiform
C
Cuneonavicular and calcaneocuboid joints.
Calcaneus
C
Tarsometatarsal joints.
Base
Navicular
1st
metatarsal
Shaft
Head
Cuboid
DTalonavicular and calcaneocuboid joints.
1st through 5th
metatarsals
Sesamoids
DMetatarsophalangeal joints.
455
Joints of the Foot (II)
Lower Limb
Fig. 33.6 Talocrural and subtalar joints
Right foot. The talocrural (ankle) joint is formed by the distal ends of
the tibia and fibula (ankle mortise) articulating with the trochlea of the
talus. The subtalar joint consists of an anterior and a posterior compart­
ment (the talocalcaneal and talocalcaneonavicular joints, respectively)
divided by the interosseous talocalcaneal ligament (see p. 458).
Tibia
Fibula
Clinical box 33.2
Range of motion of the forefoot and hindfoot
Right foot, anterior view.
Ankle mortise
Medial
malleolus
Lateral malleolus
Talocrural
joint
Navicular
Talus
Subtalar (talo­
calcaneal) joint
Sustentaculum
tali
1st
metatarsal
60°
30°
Tuberosity of
5th metatarsal
A
Eversion and pronation
of the forefoot.
Sesamoids
B
Inversion and supina­
tion of the forefoot.
Calcaneal tuberosity
A
Posterior view with foot in neutral
(0-degree) position.
Ankle mortise
Tibialis
anterior
Tibia
Medial malleolar
articular surface
Medial
malleolus
Talus, superior
trochlear surface
Tibialis
posterior
Flexor
digitorum longus
Flexor
hallucis longus
Extensor
hallucis
Extensor
digitorum
Tibiofibular
syndesmosis
Talocrural joint
Lateral malleolar
articular surface
Lateral malleolus
Subtalar (talo­
calcaneal) joint
Fibularis brevis
Fibularis longus
Posterior
tibial a. and vv.
Abductor
hallucis
B
Coronal section, proximal view. The
talocrural joint is plantar flexed, and the
subtalar joint has been sectioned through
its posterior compartment.
456
Quadratus
plantae
Calcaneus
Flexor
digitorum brevis
Fibula
Fig. 33.7 Talocrural and subtalar joints: Sagittal section
Right foot, medial view.
Interosseous
talocalcaneal lig.
Tibia
Talocrural joint
Navicular
Calcaneal
(Achilles’)
tendon
Cuneiforms
33 Ankle & Foot
Talocalcaneonavicular joint
(anterior compartment
of subtalar joint)
Talus
Talocalcaneal
joint (posterior
compartment
of subtalar joint)
2nd metatarsal
Bursa of
calcaneal tendon
Calcaneus
Short pedal
muscles
Fig. 33.8 Talocrural joint
Plantar
Plantar calcaneo­
aponeurosis
navicular lig.
Right foot. The talocrural (ankle) joint is tighter and more stable with
the foot in dorsiflexion, when the wider, anterior part of the trochlea (of
the talus) is wedged within the ankle mortise. Accordingly the joint is
looser and less stable in plantar flexion.
Tibia
Tibia
Fibula
Fibula
Medial
malleolus
Lateral
malleolus
Ankle
mortise
Medial
malleolus
Lateral
malleolus
Talus
Navicular
Navicular
Sustentac­
ulum tali
Superior trochlear surface of talus
(anterior diameter)
A
Anterior view.
Calcaneus
Superior trochlear surface of
talus (posterior diameter)
B
Posterior view.
Head
Anterior
diameter
Neck
Medial
malleolar
surface
Inferior
articular surface
Fibula
Tibia
Lateral
malleolus
Superior
trochlear
surface
Posterior
diameter
Medial
malleolus
Lateral
malleolar
surface
Lateral tubercle
C
Proximal (superior) view of talus.
Lateral malleolar
articular surface
Medial malleolar
articular surface
DDistal (inferior) view of ankle mortise.
457
Lower Limb
Joints of the Foot (III)
Fig. 33.9 Subtalar joint and ligaments
ment: the posterior compartment (talocalcaneal joint) and the anterior
compartment (talocalcaneonavicular joint).
Right foot with opened subtalar joint. The subtalar joint consists of two
distinct articulations separated by the interosseous talocalcaneal liga­
5th
metatarsal
Medial
cuneiform
Navicular
Cuboid
Tunnel for
fibularis
longus tendon
Plantar
calcaneonavicular
lig.
Long plantar lig.
Calcaneus
Sustentaculum tali
Talus
Medial cuneiform
Navicular
Plantar calcaneo­
navicular lig.
B
Plantar view. The plantar calcaneonavicular (“spring”) ligament com­
pletes the bony socket of the talocalcaneal joint. The long plantar
ligament converts the tuberosity of the cuboid bone into a tunnel for
the fibularis longus tendon (arrow).
Cuboid
Bifurcate lig.
Dorsal calcaneo­
cuboid lig.
Talus
Anterior
compart­
ment
Posterior
compart­
ment
Subtalar
joint
Tibia
Calcaneus
Interosseous
talocalcaneal lig.
Medial
malleolus
Navicular surface
Talus
Navicular
A
Dorsal view.
Medial
cuneiform
Interosseous
talocalcaneal lig.
1st metatarsal
Sustentaculum
tali
Calcaneus
Plantar
Long plantar lig.
aponeurosis
C
Medial view. The interosseous talocalcaneal ligament has been divided
and the talus displaced upward. Note the course of the plantar calca­
458
Plantar calcaneo­
navicular lig.
neonavicular ligament, which functions with the long plantar ligament
and plantar aponeurosis to support the longitudinal arch of the foot.
Fig. 33.10 Talus and calcaneus
Lateral malleolar
surface
Navicular
articular surface
Anterior talar articular
surface
Superior trochlear
surface
Cuboid articular surface
Medial malleolar
surface
Sinus tarsi
Medial
tubercle
Posterior
process
of talus
Sulcus calcanei
Posterior talar
articular
surface
Groove for
flexor hallucis
longus tendon
Lateral
tubercle
A
Dorsal (superior) view.
33 Ankle & Foot
The two tarsal bones have been separated
at the subtalar joint to demonstrate their
articular surfaces.
Sustentac­
ulum tali
Middle talar articular
surface
Calcaneal body
Superior trochlear
surface
Lateral malleolar
surface
Navicular articular
surface
Posterior calcaneal
articular surface
Posterior talar
articular surface
Middle talar
articular surface
Cuboid articular
surface
Anterior calcaneal
articular surface
Navicular articular
surface
Sinus tarsi
Cuboid articular
surface
B
Lateral view.
Middle calcaneal
articular surface
Sulcus tali
Posterior calcaneal
articular surface
Groove for
flexor hallucis
longus tendon
Calcaneal
tuberosity
Medial tubercle
Medial
process
Lateral
process
C
Plantar view.
Lateral
tubercle
Groove for
flexor hallucis
longus tendon
Superior trochlear
surface
Medial malleolar
surface
Navicular articular
surface
Posterior talar
articular surface
Anterior talar
articular surface
Sustentac­
ulum tali
Cuboid articular
surface
Calcaneus
Middle talar articular
surface
DMedial view.
459
Lower Limb
Ligaments of the Ankle & Foot
The ligaments of the foot are classified as belonging to the talocrural
joint, subtalar joint, metatarsus, forefoot, or sole of the foot. The medial
and lateral collateral ligaments, along with the syndesmotic ligaments,
are of major importance in the stabilization of the subtalar joint.
Fig. 33.11 Ligaments of the ankle and foot
Right foot. See p. 458 for inferior view.
Tibia
Fibula
Ligaments of the talocrural joint
Table 33.1
Anterior talofibular lig.
Lateral ligs.*
Posterior talofibular lig.
Calcaneofibular lig.
Anterior tibiotalar part
Anterior
tibiofibular
lig.
Medial
malleolus
Medial ligs.*
Deltoid lig.
Talus
Lateral
malleolus
Deltoid lig.
Anterior talo­
fibular lig.
Dorsal talonavicular
lig.
Bifurcate lig.
Navicular
Cuboid
Posterior tibiotalar part
Tibionavicular part
Tibiocalcaneal part
Syndesmotic ligs. of the
ankle mortise
Anterior tibiofibular lig.
Posterior tibiofibular lig.
*The medial and lateral ligs. are also known as the medial and lateral collateral
ligs.
Dorsal tarsal ligs.
Dorsal
metatarsal ligs.
1st metatarsal
Metatarso­
phalangeal
joint capsules
Interosseous
membrane
Tibia
Fibula
1st proximal
phalanx
1st distal
phalanx
A
Anterior view with talocrural joint in plan­
tar flexion.
Medial
malleolus
Deltoid lig.
Talus
Posterior tibio­
fibular lig.
Lateral
malleolus
Posterior talo­
fibular lig.
Calcaneofibular
lig.
Calcaneus
Posterior view in plantigrade foot position.
B
460
33 Ankle & Foot
Tibia
Posterior tibio­
fibular lig.
Medial
malleolus
Anterior tibio­
talar part
Talus
Tibionavicular
part
Dorsal talonavicular lig.
Tibiocalcaneal
part
Navicular
Deltoid lig.
Posterior
tibiotalar part
1st
metatarsal
1st proximal phalanx
Sustentac­
ulum tali
1st distal phalanx
Calcaneus
Medial
cuneiform
Dorsal
tarsal ligs.
Long
plantar lig.
Plantar calcaneo­
navicular lig.
C
Medial view.
Tibia
Fibula
Posterior tibiofibular lig.
Anterior tibiofibular lig.
Tibiofibular syndesmosis
(syndesmotic ligs.)
Dorsal
talonavicular lig.
Lateral
malleolus
Talus
Navicular
Dorsal tarsal ligs.
Posterior
talofibular lig.
Metatarsophalangeal
joint capsules
Anterior talo­
fibular lig.
Calcaneo­
fibular lig.
Calcaneus
Long plantar lig.
Bifurcate lig.
DLateral view.
Interosseous
talocalcaneal lig.
Cuboid
Dorsal calcaneocuboid ligs.
5th metatarsal
461
Lower Limb
Plantar Vault & Arches of the Foot
Fig. 33.12 The plantar vault
Right foot. The forces of the foot are distributed among two lateral
(fibular) and three medial (tibial) rays. The arrangement of these rays
creates a longitudinal and a transverse arch in the sole of the foot, help­
ing the foot adapt to uneven terrain and absorb vertical loads.
Head of 1st
metatarsal
Medial
rays
Head
of 5th
metatarsal
Lateral rays
B Posteromedial view.
Cuneiforms
Navicular
C
Superior view. The area outlined in
red by interconnecting the bony
points of support for the plantar
vault forms a triangle. By contrast,
the area of ground contact defined
by the plantar soft tissues (the foot­
print or podogram) is considerably
larger.
Cuboid
Talus
Calcaneus
A Superior view.
Fig. 33.13 Stabilizers of the transverse arch
Right foot. The transverse pedal arch is supported by both active and
passive stabilizing structures (muscles and ligaments, respectively).
Calcaneal
tuberosity
Note: The arch of the forefoot has only passive stabilizers, whereas the
arches of the metatarsus and tarsus have only active stabilizers.
Plantar
ligs.
Deep
transverse
metatarsal
lig.
Plantar
ligs.
Proximal phalanx
of great toe
Metatarso­
phalangeal joint
of great toe
Adductor hallucis,
transverse head
Fibularis
longus
Base of 1st
proximal phalanx
Deep transverse
metatarsal lig.
Adductor
hallucis,
transverse
head
1st metatarsal
Adductor
hallucis,
oblique head
Cuboid
B
Anterior arch
(forefoot),
proximal view.
Medial
cuneiform
C
Metatarsal arch,
proximal view.
Base of 1st
metatarsal
Adductor hallucis,
oblique head
Intermediate
cuneiform
Base of
5th
meta­
tarsal
Lateral
cuneiform
Cuboid
Tibialis
posterior
Medial
malleolus
Sustentac­
ulum tali
Calcaneus
Plantar view.
A
462
Talus
DTarsal region,
proximal view.
Medial
cuneiform
Tibialis
posterior
Fibularis
longus
Tuberosity of 5th
metatarsal
Fig. 33.14 Stabilizers of the longitudinal arch
Right foot, medial view.
Navicular
Flexor digitorum
longus
Talus
Medial
cuneiform
Medial
malleolus
Medial
tubercle
Plantar
Long plantar
aponeurosis
lig.
Plantar
calcaneocuboid
lig.
Plantar
calcaneonavicular
lig.
33 Ankle & Foot
Flexor hallucis
longus
Sustentac­
ulum tali
A
Passive stabilizers of the longitudinal arch. The main passive stabilizers of the longitudinal arch are the plantar aponeurosis (strongest
component), the long plantar ligament, and the plantar calcaneona­
vicular ligament (weakest component).
Fibularis longus
tendon
Flexor hallucis
brevis
Plantar interossei
Calcaneal
(Achilles’)
tendon
Dorsal interossei
Adductor
hallucis
Quadratus
plantae
Abductor
hallucis
Lumbrical
Flexor digitorum brevis
Plantar aponeurosis
B
Active stabilizers of the longitudinal arch. Sagittal section at the
level of the second ray. The major active stabilizers of the foot are
the abductor hallucis, flexor hallucis brevis, flexor digitorum brevis,
quadratus plantae, and abductor digiti minimi.
463
Lower Limb
Muscles of the Sole of the Foot
Fig. 33.15 Plantar aponeurosis
Right foot, plantar view. The plantar aponeurosis is a tough aponeurotic
sheet, thickest at the center, that blends with the dorsal fascia (not
shown) at the borders of the foot.
Annular ligs.
Cruciform ligs.
Superficial
transverse
metatarsal lig.
Transverse
fascicles
Flexor digiti
minimi brevis
3rd plantar
interosseus
Tuberosity of
5th metatarsal
Abductor
digiti minimi
Lateral
plantar septum
Plantar
aponeurosis
Fibularis
longus
Fig. 33.16 Intrinsic muscles
of the sole of the foot
Right foot, plantar view.
Flexor
hallucis brevis
Medial
plantar septum
Abductor
hallucis
Tibialis posterior
Flexor
digitorum longus
Flexor
hallucis longus
Calcaneal tuberosity
Flexor
digitorum
brevis
tendons
3rd plantar
interosseus
4th dorsal
interosseus
Flexor digiti
minimi brevis
Flexor
hallucis
longus
tendon
Lumbricals
Flexor
hallucis brevis
Flexor
digitorum
brevis
Abductor
digiti minimi
Abductor
hallucis
Fibularis
longus
Plantar
aponeurosis
Tibialis posterior
Flexor
digitorum longus
Flexor
hallucis longus
Superficial (first) layer. Removed: Plantar aponeurosis, including the
A
superficial transverse metacarpal ligament.
464
33 Ankle & Foot
Flexor
digitorum brevis
tendons
Flexor
digitorum longus
tendons
Flexor hallucis
longus tendon
Adductor hallucis,
transverse head
Lumbricals
3rd plantar
interosseus
Flexor
hallucis brevis
4th dorsal
interosseus
Flexor
digitorum longus
Flexor digiti
minimi brevis
Abductor
digiti minimi
Fibularis longus
tendon
Abductor
hallucis
Quadratus
plantae
Fibularis longus
Tibialis posterior
Flexor
digitorum
brevis
Flexor digitorum
longus
Flexor hallucis
longus
Flexor
digitorum
longus
tendons
Flexor
digitorum
brevis
tendons
Flexor hallucis
longus
Lumbricals
Transverse head
B
Second layer. Removed: Flexor digitorum brevis.
Oblique head
Plantar and
dorsal interossei
Opponens
digiti minimi
Adductor
hallucis
Flexor hallucis brevis,
medial and lateral heads
Abductor hallucis
Flexor digiti
minimi brevis
Tuberosity of
5th metatarsal
Fibularis brevis
Long plantar lig.
Fibularis longus
tendon
Tibialis posterior
tendon
Quadratus plantae
Fibularis longus
Abductor digiti
minimi
C
Third layer. Removed: Abductor digiti minimi, abductor
hallucis, quadratus plantae, lumbricals, and tendons of
insertion of the flexors digitorum and hallucis longus.
Abductor hallucis
Flexor
digitorum longus
Flexor
hallucis longus
465
Muscles & Tendon Sheaths of the Foot
Lower Limb
Fig. 33.17 Deep intrinsic muscles
of the sole of the foot
Right foot, plantar view.
Plantar ligs.
1st through 4th lumbricals
Transverse head
Oblique head
Flexor digiti minimi
brevis
Adductor
hallucis
Flexor hallucis brevis
1st dorsal interosseus
3rd plantar interosseus
4th dorsal interosseus
2nd dorsal interosseus
Abductor hallucis
Adductor hallucis, oblique head
1st plantar interosseus
Opponens digiti minimi
Flexor hallucis brevis
Tibialis anterior tendon
Flexor digiti minimi brevis
Fibularis longus tendon
Plantar calcaneonavicular lig.
Long plantar lig.
Fibularis brevis
Tibialis posterior tendon
Quadratus plantae
Fibularis longus
Abductor digiti minimi
Flexor
digitorum
longus
Abductor
hallucis
Flexor digitorum brevis
Plantar aponeurosis
Flexor digiti
minimi brevis
A
Fourth layer. Removed: Adductor hallucis,
flexor digiti minimi brevis, and flexor hal­
lucis brevis.
Flexor
hallucis longus
Flexor digitorum
brevis
1st through 4th
dorsal interossei
Flexor hallucis brevis
Abductor digiti minimi
Abductor hallucis
Adductor hallucis
1st through 3rd
plantar interossei
Adductor hallucis,
transverse head
Opponens digiti minimi
3rd plantar interosseus
4th dorsal interosseus
2nd plantar interosseus
3rd dorsal interosseus
Adductor hallucis, oblique head
Flexor digiti minimi brevis
Abductor digiti minimi
and fibularis brevis
1st dorsal interosseus
2nd dorsal interosseus
1st plantar interosseus
Tibialis anterior
Fibularis longus
Tibialis posterior
Flexor hallucis brevis
Abductor digiti minimi
Flexor digitorum brevis
B
Muscle origins are shown in red,
insertions in blue.
466
Quadratus plantae
Abductor hallucis
Fig. 33.18 Tendon sheaths and retinacula of the ankle
Fibularis
longus
Tibialis
anterior
Tibia
Extensor
digitorum longus
Extensor
hallucis longus
Fibularis
brevis
Superior
extensor
retinaculum
33 Ankle & Foot
Right foot. The superior and inferior extensor retinacula retain the long
extensor tendons, the fibularis retinacula hold the fibular muscle ten­
dons in place, and the flexor retinaculum retains the long flexor tendons.
Triceps surae
Medial
malleolus
Inferior extensor
retinaculum
Lateral
malleolus
Fibularis
brevis
Tendon sheath
Tibialis
anterior
Extensor hallucis brevis
Fibularis tertius
Tibia
Extensor
digitorum brevis
Tuberosity of
5th metatarsal
Interossei
Extensor
hallucis longus
tendon
Flexor
digitorum longus
Superior
extensor
retinaculum
Extensor digitorum
longus tendons
Abductor
digiti minimi
Triceps
surae
Tibialis posterior
Medial malleolus
Inferior
extensor
retinaculum
Flexor
hallucis longus
Extensor
hallucis longus
Tendon sheath
Calcaneal
(Achilles’) tendon
Flexor
retinaculum
Flexor
hallucis longus
A
Anterior view with talocrural
joint in plantar flexion.
Tuberosity of
5th metatarsal
Flexor hallucis Tibialis
longus
anterior
Fibularis
longus
Tibialis anterior
Flexor
digitorum longus
Calcaneal
tuberosity
B
Medial view.
Extensor hallucis longus
Triceps surae
Extensor digitorum longus
Fibularis brevis
Fibula
Superior
extensor retinaculum
Fibularis
tertius
Inferior
extensor retinaculum
Extensor
digitorum brevis
Extensor digitorum
longus tendons
Lateral malleolus
Calcaneal
(Achilles’) tendon
Extensor
hallucis longus tendon
Extensor
digitorum
brevis tendons
Superior
fibular retinaculum
Fibularis longus
Inferior
fibular retinaculum
Fibularis
brevis
C
Lateral view.
Tibialis
posterior
Abductor
digiti minimi
Tuberosity of
5th metatarsal
Dorsal aponeurosis
467
Lower Limb
Muscle Facts (I)
The dorsal surface (dorsum) of the foot contains only two muscles, the
extensor digitorum brevis and the extensor hallucis brevis. The sole of
the foot, however, is composed of four complex layers that maintain
the arches of the foot.
Fig. 33.19 Intrinsic muscles of the dorsum of the foot
Right foot, dorsal view.
Extensor digitorum
brevis tendons
5th distal phalanx
1st proximal
phalanx
5th middle phalanx
5th proximal phalanx
S
A
Extensor hallucis
brevis tendon
5th metatarsal
Extensor hallucis brevis
Medial cuneiform
A
Schematic.
Extensor digitorum brevis
Intermediate cuneiform
Navicular
Tuberosity of 5th metatarsal
Superior trochlear surface
Talus
Calcaneus
B
Dorsal muscles of the foot.
Table 33.2
Intrinsic muscles of the dorsum of the foot
Muscle
Origin
① Extensor digitorum brevis
Calcaneus
(dorsal surface)
② Extensor hallucis brevis
Insertion
2nd to 4th toes (at dorsal aponeuroses and bases of the
middle phalanges)
1st toe (at dorsal aponeurosis and proximal phalanx)
MTP, metatarsophalangeal; PIP, proximal interphalangeal.
468
Innervation
Deep fibular
n. (L5, S1)
Action
Extension of the MTP and PIP joints of
the 2nd to 4th toes
Extension of the MTP joints of the 1st toe
Fig. 33.20 Superficial intrinsic muscles
of the sole of the foot
Right foot, plantar view.
33 Ankle & Foot
Cruciform
ligs.
Sesamoids
A
S
D
Flexor
digitorum brevis
Tuberosity of
5th metatarsal
A
First layer, schematic.
Tuberosity of
cuboid
Abductor
hallucis
Abductor
digiti minimi
Plantar
aponeurosis
Calcaneal
tuberosity
B
Intrinsic muscles of the sole, first layer.
Table 33.3
Superficial intrinsic muscles of the sole of the foot
Muscle
Origin
Insertion
① Abductor hallucis
Calcaneal tuberosity
(medial process);
flexor retinaculum,
plantar aponeurosis
1st toe (base of proximal phalanx via
the medial sesamoid)
② Flexor digitorum brevis
③ Abductor digiti minimi
Calcaneal tuberosity
(medial tubercle),
plantar aponeurosis
Innervation
Medial plantar
n. (S1, S2)
2nd to 5th toes (sides of middle
phalanges)
5th toe (base of proximal phalanx),
5th metatarsal (at tuberosity)
Action
• 1st MTP joint: flexion and abduction of the 1st toe
• Supports the longitudinal arch
• Flexes the MTP and PIP joints of the 2nd to 5th toes
• Supports the longitudinal arch
Lateral plantar
n. (S1–S3)
• Flexes the MTP joint of the 5th toe
• Abducts the 5th toe
• Supports the longitudinal arch
MTP, metatarsophalangeal; PIP, proximal interphalangeal.
469
Lower Limb
Muscle Facts (II)
Fig. 33.21 Deep intrinsic muscles of the sole of the foot
Right foot, plantar view, schematics.
S
⑥
④
J
③
K
⑤
A
Flexor digitorum
longus tendon
A
Second layer.
Table 33.4
B
Third layer.
Deep intrinsic muscles of the sole of the foot
Muscle
Origin
Insertion
Innervation
Action
① Quadratus
plantae
Calcaneal tuberosity (medial and
plantar borders on plantar side)
Flexor digitorum longus
tendon (lateral border)
Lateral plantar n. (S1–S3)
Redirects and augments the pull of flexor
digitorum longus
② Lumbricals
(four muscles)
Flexor digitorum longus tendons
(medial borders)
2nd to 5th toes (at dorsal
aponeuroses)
③ Flexor hallucis
brevis
Cuboid, lateral cuneiforms, and
plantar calcaneocuboid lig.
1st toe (at base of proximal
phalanx via medial and lateral
sesamoids)
④ Adductor hallucis
Oblique head: 2nd to 4th
metatarsals (at bases) cuboid
and lateral cuneiforms
Transverse head: MTP joints of
3rd to 5th toes, deep transverse
metatarsal lig.
1st proximal phalanx (at base,
by a common tendon via the
lateral sesamoid)
⑤ Flexor digiti
minimi brevis
5th metatarsal (base), long
plantar lig.
5th toe (base of proximal
phalanx)
⑥ Opponens digiti
minimi*
Long plantar lig.; fibularis longus
(at plantar tendon sheath)
5th metatarsal
⑦ Plantar interossei
(three muscles)
3rd to 5th metatarsals (medial
border)
3rd to 5th toes (medial base of
proximal phalanx)
1st interosseus: 2nd proximal
phalanx (medial base)
⑧ Dorsal interossei
(four muscles)
1st to 5th metatarsals (by two
heads on opposing sides)
2nd to 4th interossei:
2nd to 4th proximal phalanges
(lateral base),
2nd to 4th toes (at dorsal
aponeuroses)
IP, interphalangeal; MTP, metatarsophalangeal. *May be absent.
470
C
Fourth layer.
1st lumbrical: medial plantar
n. (S2, S3)
2nd to 4th lumbrical: lateral
plantar n. (S2, S3)
Medial head: medial plantar
n. (S1, S2)
Lateral head: lateral plantar
n. (S1, S2)
Lateral plantar n., deep
branch (S2, S3)
Lateral plantar n., superficial
branch (S2, S3)
• Flexes the MTP joints of 2nd to 5th toes
• Extension of IP joints of 2nd to 5th toes
• Adducts 2nd to 5th toes toward the
big toe
• Flexes the first MTP joint
• Supports the longitudinal arch
• Flexes the first MTP joint
• Adducts big toe
• Transverse head: supports transverse
arch
• Oblique head: supports longitudinal
arch
Flexes the MTP joint of the little toe
Pulls 5th metatarsal in plantar and medial
direction
• Flexes the MTP joints of 3rd to 5th toes
• Extension of IP joints of 3rd to 5th toes
• Adducts 3rd to 5th toes toward 2nd toe
Lateral plantar n. (S2, S3)
• Flexes the MTP joints of 2nd to 4th toes
• Extension of IP joints of 2nd to 4th toes
• Abducts 3rd and 4th toes from 2nd toe
Fig. 33.22 Deep intrinsic muscles of the sole of the foot
Right foot, plantar view.
33 Ankle & Foot
Flexor
digitorum
longus
tendons
1st dorsal
interosseus
3rd plantar
interosseus
1st through
4th
lumbricals
Medial
cuneiform
Tuberosity
of 5th
metatarsal
Long
plantar
lig.
Fibularis
longus
tendon
Quadratus
plantae
Flexor
digitorum
longus
Flexor
digitorum
brevis
Lateral sesamoid
Metatarso­
phalangeal
joint
capsules
Opponens
digiti
minimi
Flexor
digiti
minimi
brevis
Medial sesamoid
Transverse
head
Oblique
head
Medial
head
Lateral
head
Adductor
hallucis
Flexor
hallucis
brevis
Sustentaculum
tali
Calcaneus
Fibularis
longus
tendon
A
Intrinsic muscles of the sole, second and
fourth layers.
Long plantar
lig.
Lateral process
Tibialis
posterior
tendon
Plantar
calcaneonavicular
lig.
Medial process
B
Intrinsic muscles of the sole, third layer.
471
34
Neurovasculature
Lower Limb
Arteries of the Lower Limb
Fig. 34.1 Arteries of the lower limb and
the sole of the foot
Adductor
hiatus
Abdominal
aorta
Common
iliac a.
Internal iliac a.
Deep circumflex iliac a.
Superior and inferior
gluteal aa.
Superficial
epigastric a.
External iliac a.
Superficial circumflex iliac a.
Inferior
epigastric a.
Piriformis
Adductor
magnus
Medial superior
genicular a.
Middle genicular a.
Medial inferior
genicular a.
External
pudendal aa.
Anterior
tibial a.
Lateral circumflex femoral a.
Deep a. of
the thigh
1st through 4th
perforating aa.
Posterior
tibial a.
Popliteal a.
Lateral superior
genicular a.
Sural aa.
Lateral inferior
genicular a.
Posterior tibial
recurrent a.
Anterior tibial
recurrent a.
Fibular a.
Medial circumflex
femoral a.
Muscular brs.
Femoral a.
Adductor canal
(with adductor magnus)
Communicating br.
Popliteal a.
Lateral superior
and inferior
genicular aa.
Adductor
hiatus
Descending
genicular a.
Medial superior and
inferior genicular aa.
Medial malleolar
brs.
Medial
plantar a.
Perforating br.
Lateral malleolar brs.
Calcaneal brs.
B
Right leg, posterior view.
Anterior tibial
recurrent a.
Interosseous
membrane
Proper plantar
digital aa.
Anterior
tibial a.
Plantar metatarsal aa.
Deep
plantar arch
Anterior lateral
malleolar a.
Lateral
tarsal a.
Arcuate a.
Anterior medial
malleolar a.
Dorsal
pedal a.
Lateral
plantar a.
Dorsal metatarsal
aa.
Common plantar
digital aa.
Superficial br.
Deep br.
Abductor
hallucis
Medial
plantar a.
Posterior
tibial a.
A
Right leg, anterior view.
472
C
Sole of right foot, plantar view.
Medial
plantar a.
Fig. 34.2 Segments of the femoral artery
The blood supply to the lower limbs originates from the femoral artery.
Color is used to identify the named distal segments of this vessel.
Internal
iliac a.
External
iliac a.
Right leg. The artery passes posteriorly through the adductor muscles
of the medial thigh to supply the muscles of the posterior compart­
ment via three to five perforating branches. Ligation of the femoral
artery proximal to the origin of the deep artery of the thigh (left)
is well tolerated owing to the collateral blood supply (arrows) from
branches of the internal iliac artery that anastomose with the perfor­
ating branches.
Inguinal
lig.
Deep a. of
the thigh
Adductor
magnus
Adductor
longus
34 Neurovasculature
Abdominal
aorta
Common
iliac a.
Fig. 34.3 Deep artery of the thigh
Femoral a.
1st
perforating a.
Adductor
canal
2nd
perforating a.
Adductor
hiatus
Adductor
brevis
Femoral a.
3rd
perforating a.
Popliteal a.
Popliteal a.
passing through
adductor hiatus
Anterior
tibial a.
Posterior
tibial a.
Interosseous
membrane
Fibular a.
Clinical box 34.1
Femoral head necrosis
Dislocation or fracture of the femoral head (e.g., in patients with
osteoporosis) may tear the femoral neck vessels, resulting in femoral
head necrosis.
Dorsal
pedal a.
Medial
plantar a.
Fig. 34.4 Arteries of the femoral head
Acetabular roof
Anterior view.
Head of femur
Lig. of head
of femur
Femoral
neck vessels
Fibrous
membrane
Acetabu­
lar fossa
Synovial
membrane
Lig. of head
of femur
A. of lig. of
head of femur
Synovial
membrane
Fibrous
membrane
Acetabular
labrum
Obturator a.
Medial circum­
flex femoral a.
Zona
orbicularis
Iliopsoas
tendon
Deep a. of
the thigh
Lateral circumflex
femoral a.
Medial circumflex
femoral a.
Lesser trochanter
A
Right femur.
B
Right femur, coronal section.
473
Lower Limb
Veins & Lymphatics of the Lower Limb
Fig. 34.5 Superficial (epifascial)
veins of the lower limb
Superficial
circumflex
iliac v.
Femoral v.
(in saphenous
opening)
Anterior
femoral
cutaneous v.
Superficial
epigastric v.
Fig. 34.6 Deep veins of the lower limb
External
pudendal vv.
Inguinal lig.
Accessory
saphenous v.
Great
saphenous v.
Piriformis
External
iliac v.
Lateral
circumflex
femoral
vv.
Medial
circumflex
femoral
vv.
Deep v.
of thigh
Great
saphenous
v.
Femoral
v.
Accessory
saphenous
v.
Posterior
tibial vv.
Adductor
canal
Adductor
hiatus
Popliteal
v.
Dorsal venous
network
Popliteal v.
Dorsal venous
arch
Anterior
tibial v.
Fibular vv.
Small
saphenous v.
Adductor
magnus
Lateral
malleolus
Genicular vv.
A
Right limb, anterior view.
Small
saphenous v.
Great
saphenous v.
B Right limb, posterior view.
Fig. 34.7 Veins of the sole of the foot
Right foot, plantar view.
Femoro­
popliteal v.
Anterior
tibial vv.
Popliteal v.
Great
saphenous v.
Small
saphenous v.
Posterior
arch v.
Small
saphenous v.
Dorsal
venous
network
of the foot
A
Right limb, anterior view.
B Right limb, posterior view.
474
Plantar
digital vv.
Plantar
metatarsal vv.
Plantar
venous
arch
Lateral
plantar v.
Small
saphenous v.
Dorsal
venous
arch
Medial
plantar v.
Great
saphenous v.
Posterior
tibial vv.
Fig. 34.8 Clinically important
­perforating veins
Fig. 34.9 Superficial lymph nodes
Right limb. Arrows indicate the main directions of lymphatic drainage.
Right leg, medial view.
34 Neurovasculature
Anus
Superficial
inguinal
l.n.
External
iliac v.
Great
saphenous v.
Scrotum
Femoral v.
Antero­
medial
bundle
Superficial
popliteal
l.n.
Great
saphenous
v.
Dodd’s vv.
Small
saphenous
v.
Femoral v.
Great
saphenous
v.
A
Anterior view.
Postero­
lateral
bundle
B
Posterior view.
Boyd’s vv.
Lumbar lymph nodes
Common iliac lymph nodes
Inferior vena cava
Posterior
tibial vv.
Posterior
arch v.
Cockett’s
vv.
• Receive drainage from
– Deep inguinal l.n.
– Urinary bladder, shaft
and glans of penis,
uterus
Internal iliac lymph nodes
Superolateral
l.n.
Superomedial
l.n.
Inferior
l.n.
Internal
iliac v.
Superficial inguinal lymph nodes
Inguinal lig.
• Receive drainage from
– Skin of the limb
(except the calf and the medial
border of the foot)
– Abdominal wall below the umbilicus
– Lower back
– Gluteal region, bowel, anal region
– External genitalia
(in women, also the uterine fundus
along the round lig.)
Fig. 34.10 Lymph nodes and
­lymphatic drainage
Right limb, anterior view. Arrows indicate
direction of lymphatic drainage. Yellow
shading: superficial nodes; green shading:
deep nodes.
Common iliac v.
External
iliac v.
External iliac lymph nodes
Great
saphenous
v.
• Receive drainage from
– Pelvic organs
– Pelvic wall
– Gluteal muscles
– Erectile tissues
– Deep perineal region
Deep inguinal
lymph nodes
• Receive drainage from
– Deep portions of
the lower limb
Femoral v.
Deep popliteal lymph nodes
Superficial popliteal
lymph nodes
• Receive drainage from
– Leg
– Foot
• Receive drainage from
– Lateral border of foot
– Calf
Popliteal v.
Small
saphenous v.
475
Lower Limb
Lumbosacral Plexus
The lumbosacral plexus supplies sensory and motor innervation to the
lower limb. It is formed by the anterior (ventral) rami of the lumbar and
sacral spinal nerves, with contributions from the subcostal nerve (T12)
and coccygeal nerve (Co1). The lumbar plexus mainly supplies the
anterior and medial parts of the thigh with a small contribution to the
medial leg. The sacral plexus supplies the posterior thigh and most of
the leg and foot.
Subcostal n.
Iliohypogastric n.
Ilioinguinal n.
Genitofemoral n.
Pudendal n.
Inferior
clunial nn.
Nerves of the lumbosacral plexus
Table 34.1
Lumbar plexus
Iliohypogastric n.
L1
Ilioinguinal n.
L1
Obturator n.
Genitofemoral n.
L1–L2
Lateral cutaneous
n. of the thigh
Lateral cutaneous n. of the thigh
L2–L3
Femoral n.
Obturator n.
L2–L4
Femoral n.
p. 479
p. 480
p. 481
Sacral plexus
Posterior
cutaneous n.
of the thigh
Saphenous n.
Sciatic n.
Superior gluteal n.
L4–S1
Inferior gluteal n.
L5–S2
Posterior cutaneous n. of the thigh
S1–S3
p. 482
Common fibular n.
L4–S2
p. 484
Tibial n.
L4–S3
p. 485
S2–S4
pp. 284–285
Sciatic n.
Pudendal n.
p. 483
Tibial n.
Common
fibular n.
Deep
fibular n.
Tibial n.
Superficial
fibular n.
Sural n.
Medial and
lateral
plantar nn.
476
Lateral sural
cutaneous n. (with
communicating br.)
Clinical box 34.2
Injuries to nerves of the lumbar and sacral plexuses
Similar to nerve injuries of the upper limb, injuries involving nerves of
the lumbosacral plexus are best understood though an appreciation of
the plexus organization. The lumbar plexus arises from higher levels
(L1–L4) of the spinal cord and supplies muscles of the abdominal wall
and anterior and medial thigh. The sacral plexus arises from lower levels
(L4–S4) of the spinal cord and supplies the perineum and, via the large
sciatic nerve, the posterior thigh, entire leg and most of the foot. Nerves
of the lumbar and sacral plexuses are less likely to be injured at the root
level than those of the brachial plexus, although exceptions to this
are the obturator and femoral nerves that may be compromised by
herniation of intervertebral disks at L4 or L5 as they pass through the
intervertebral foramina. Peripheral nerve injuries, such as that of the
common fibular nerve, can occur in places where the nerve is superficial
and passes close to a bony prominence.
Fig. 34.11 Lumbosacral plexus
L1
L2
Iliohypo­
gastric n.
Ilioinguinal n.
Lumbar
plexus
L3
L4
Genito­
femoral n.
Lateral
cutaneous n.
of the thigh
34 Neurovasculature
Right side, anterior view.
Spinal nerve contributions to nerves of the lumbar and sacral plexuses.
Separation of the anterior rami into anterior and posterior divisions are
not as neatly demarcated in the lumbosacral plexus as they are in the
brachial plexus of the upper limb. Where clearly separated into nerves
they are indicated as: green = anterior ­division, blue = posterior divi­
sion. Note: Nerves of the sacral plexus not shown: n. to piriformis
(S1, S2), n. to obturator internus (L5, S1), and n. to quadratus femoris
(L5, S1).
L5
Obturator n.
S1
Femoral n.
T12
vertebra
12th rib
S2
Superior
gluteal n.
Subcostal n.
S3
Inferior
gluteal n.
S4
Sciatic n.
Sacral
plexus
Ilioinguinal n.
Co1
Common
fibular n.
Coccygeal
n.
Genito­
femoral n.
L5
vertebra
Coccygeal
plexus
Lumbosacral
trunk
Pudendal n.
Structure of the lumbosacral plexus.
A
Iliohypogastric n.
S5
Tibial n.
Posterior
cutaneous n.
of the thigh
L1
vertebra
S1
vertebra
Obturator n.
Femoral n.
Lateral cutaneous n.
of the thigh
Superior
and inferior
gluteal nn.
Sciatic n.
Coccygeal plexus,
anococcygeal nn.
Coccygeal n.
Muscular brs.
Femoral n.
Anterior
femoral
cutaneous
brs.
Pudendal n.
Inguinal lig.
Muscular brs.
Saphenous n.
Anterior br.
Posterior br.
Obturator n.
Muscular brs.
B
Course of the lumbosacral plexus. Distribution of anterior rami of
lumbar (yellow/orange) and sacral (blue/green) spinal nerves to the
gluteal region and lower limb.
Sciatic n.
(common fibular n.
and tibial n.)
477
Lower Limb
Nerves of the Lumbar Plexus
Table 34.2
Nerves of the lumbar plexus
Nerve
Level
Iliohypogastric n.
L1
Innervated muscle
Cutaneous branches
Anterior and lateral cutaneous brs.
Transversus abdominis and internal oblique (inferior portions)
♂: Anterior scrotal nn.
♀: Anterior labial nn.
Ilioinguinal n.
L1
Genitofemoral n.
L1–L2
♂: Cremaster (genital br.)
Genital br.
Femoral br.
Lateral cutaneous n. of the thigh
L2–L3
—
lateral cutaneous n. of the thigh
Obturator n.
L2–L4
See p. 480
Femoral n.
L2–L4
See p. 481
T12–L4
Psoas major
Quadratus lumborum
Iliacus
Intertransversarii lumborum
Short, direct muscular brs.
—
Fig. 34.12 Cutaneous innervation of the inguinal region
Right male inguinal region, anterior view.
Ilioinguinal n.
Iliohypo­
gastric n.
Genitofemoral n.
Lateral
cutaneous
br.
Anterior
cutaneous
br.
Superficial inguinal ring
Ilioinguinal n.
Lateral cutaneous
n. of the thigh
Genital br.
Femoral br.
Genito­
femoral n.
Anterior scrotal brs.
Femoral n.,
anterior
cutaneous brs.
Clinical box 34.3
Entrapment of the lateral femoral cutaneous nerve
(meralgia paresthetica)
Ischemia (diminished blood flow) of the lateral cutaneous nerve of the thigh
can result when the nerve is stretched or entrapped by the inguinal ligament
(see Fig. 34.11B) during hyperextension of the hip or with increased
lordosis (curvature) of the lumbar spine, as often occurs during pregnancy.
478
This results in pain, numbness, or paresthesia (tingling or burning) on the
outer aspect of the thigh. It is most commonly found in obese or diabetic
individuals and in pregnant women.
Fig. 34.13 Nerves of the lumbar plexus
Right side, anterior view with the anterior abdominal wall removed.
Internal
oblique
External
oblique
Iliac crest
Lateral
cutaneous
br.
Inguinal
lig.
Transversus
abdominis
Quadratus
lumborum
Iliohypogastric n.
Internal
oblique
Anterior cutane­
ous br.
Superficial
inguinal ring
Ilioinguinal n.
Psoas major
Psoas major
Iliacus
Quadratus
lumborum
34 Neurovasculature
Transversus
abdominis
Iliacus
Inguinal
lig.
Ilioinguinal n.
Superficial
inguinal ring
Spermatic
cord
B
Ilioinguinal nerve.
A
Iliohypogastric nerve.
Quadratus
lumborum
Quadratus
lumborum
Genitofemoral n.
Psoas major
Psoas major
Anterior superior
iliac spine
Lateral cutaneous
n. of the thigh
Iliacus
Inguinal
lig.
Rectus
abdominis
Inguinal
lig.
Femoral
br.
Iliacus
Genital br.
Fascia lata
Spermatic
cord
Spermatic cord
C
Genitofemoral nerve.
DLateral cutaneous nerve of the thigh.
479
Nerves of the Lumbar Plexus: Obturator & Femoral Nerves
Lower Limb
Fig. 34.15 Obturator nerve
Right side, anterior view.
Fig. 34.14 Obturator nerve: Cutaneous distribution
L4
vertebra
Right leg, medial view.
Cutaneous br.
Obturator n.
Linea
terminalis
Pectineus
Obturator
externus
Anterior br.
Posterior br.
Adductor
brevis
Muscular brs.
Adductor
longus
Adductor
magnus
Cutaneous br.
Gracilis
Table 34.3
Obturator nerve (L2–L4)
Motor branches
Innervated muscles
Direct br.
Obturator externus
Adductor longus
Anterior br.
Adductor brevis
Gracilis
Pectineus
Posterior br.
Sensory branches
Cutaneous br.
480
Adductor magnus
Fig. 34.16 Femoral nerve
Right side, anterior view.
L4
vertebra
Fig. 34.17 Femoral nerve: Cutaneous
distribution
Right limb, anterior view.
34 Neurovasculature
Psoas major
Muscular br.
Iliacus
Inguinal lig.
Iliopsoas
Sartorius
Anterior
cutaneous
brs.
Femoral n.
Muscular brs.
Anterior
cutaneous
brs.
Rectus femoris
Infra­
patellar br.
Pectineus
Saphenous n.
Medial
cutaneous
brs.
Muscular brs.
Saphenous n.
Vastus
intermedius
Quadriceps
femoris
Vastus
lateralis
Rectus
femoris
Vastus
medialis
Anteromedial
intermuscular
septum
Sartorius
Table 34.4
Femoral nerve (L2–L4)
Motor branches
Innervated muscles
Iliopsoas
Infrapatellar br.
Saphenous n.
Muscular brs.
Pectineus
Sartorius
Quadriceps femoris
Sensory branches
Anterior cutaneous br.
Saphenous n.
481
Lower Limb
Nerves of the Sacral Plexus
Nerves of the sacral plexus
Table 34.5
Nerve
Level
Innervated muscle
Cutaneous branches
Superior gluteal n.
L4–S1
Gluteus medius
Gluteus minimus
Tensor fasciae latae
—
Inferior gluteal n.
L5–S2
Gluteus maximus
—
Posterior cutaneous n. of the thigh
S1–S3
—
Posterior cutaneous n. of the thigh
S1–S2
Piriformis
—
L5–S1
Obturator internus
Gemelli
—
Quadratus femoris
—
N. of piriformis
Direct branches
N. of obturator internus
N. of quadratus femoris
Sciatic n.
Common fibular n.
L4–S2
See p. 484
Tibial n.
L4–S3
See p. 485
S2–S4
See pp. 284–285
Pudenal n.
Inferior clunial nn.
Perineal brs.
Fig. 34.18 Cutaneous innervation of the gluteal region
Right limb, posterior view.
Fig. 34.19 Posterior cutaneous nerve of the thigh:
Cutaneous distribution
Right limb, posterior view.
Superior clunial nn.
(posterior rami
of L1–L3)
Middle clunial nn.
(posterior rami
of S1–S3)
Lateral br.
(iliohypogastric n.)
Inferior clunial nn.
Inferior clunial nn.
(Posterior cutaneous
n. of the thigh)
Perineal brs.
Posterior cutaneous
n. of the thigh
Fig. 34.20 Emerging spinal nerve
Horizontal section, superior view.
Anterior
(ventral)
root
Anterior
sacral
foramen
Anterior
(ventral) ramus
(to sacral plexus)
Posterior
(dorsal)
ramus
Cauda
equina
482
Posterior
(dorsal)
root
Posterior
sacral
foramen
Lateral br. (to
the clunial nn.)
Small gluteal muscle weakness
The small gluteal muscles on the stance side stabilize the pelvis in the
coronal plane (A). Weakness or paralysis of the small gluteal muscles from
damage to the superior gluteal nerve (e.g., due to a faulty intramuscular
injection) is manifested by weak abduction of the affected hip joint.
In a positive Trendelenburg’s test, the pelvis sags toward the normal,
unsupported side (B). Tilting the upper body toward the affected side
shifts the center of gravity onto the stance side, thereby elevating the
pelvis on the swing side (Duchenne’s limp) (C). With bilateral loss of the
small gluteals, the patient exhibits a typical waddling gait.
Fig. 34.21 Nerves of the sacral
plexus
Right limb.
Gluteus
medius
Superior
gluteal n.
34 Neurovasculature
Clinical box 34.4
Insufficient
small gluteals
Gluteus medius
and minimus
Anterior
superior
iliac spine
Shifted
center
of gravity
Pelvis
sags
Tensor
fasciae
latae
Iliotibial
tract
Stance leg
Swing leg
Normal gait.
A
B
Small gluteal
muscle weakness.
C
Duchenne’s limp.
A
Superior gluteal nerve. Lateral view.
Piriformis
(with n.)
Inferior
gluteal n.
Gluteus
maximus
Muscular
brs.
Sciatic n.
Inferior gluteal nerve. Posterior view.
B
Obturator
internus (with n.)
Sacrotuberous
lig.
Sciatic n.
Gemellus
superior
Gemellus
inferior
Quadratus
femoris
(with n.)
Direct branches. Posterior view.
C
483
Lower Limb
Nerves of the Sacral Plexus: Sciatic Nerve
The sciatic nerve gives off several direct muscular branches before
dividing into the tibial and common fibular nerves proximal to the
popliteal fossa.
Fig. 34.23 Common fibular nerve
Fig. 34.22 Common fibular nerve: Cutaneous distribution
Right limb, lateral view.
Anterior
superior
iliac spine
Lateral sural
cutaneous n.
Sciatic n.
Fibular
communicating br.
Medial dorsal
cutaneous n.
Medial dorsal
cutaneous n.
Intermediate
dorsal
cutaneous n.
Intermediate
dorsal cuta­
neous n.
Lateral cutaneous
n. of big toe
Deep
fibular
n.
Medial cutaneous
n. of 2nd toe
A
Right leg, anterior view.
Table 34.6
Superficial
fibular n.
Tibial n.
Common
fibular n.
B
Right leg, lateral view.
Common fibular nerve (L4–S2)
Nerve
Innervated muscles
Sensory branches
Direct branches from
sciatic n.
Bicep femoris (short
head)
—
Superficial fibular n.
Fibularis brevis and
longus
Medial dorsal cutaneous n.
Intermediate dorsal
cutaneous n.
Deep fibular n.
Tibialis anterior
Extensors digitorum
brevis and longus
Extensors hallucis brevis
and longus
Fibularis tertius
Lateral cutaneous n. of
big toe
Medial cutaneous n. of
2nd toe
Biceps femoris,
long head
Neck of fibula
Head of fibula
Deep
fibular n.
Superficial
fibular n.
Tibialis
anterior
Fibularis
longus
Extensor
digitorum longus
Fibularis
brevis
Extensor
hallucis longus
Lateral
malleolus
484
Biceps femoris,
short head
Superficial
fibular n.
Medial dorsal
cutaneous n.
Intermediate
dorsal cuta­
neous n.
Fig. 34.24 Tibial nerve
Fig. 34.25 Tibial nerve: Cutaneous
distribution
Right limb.
Right lower limb, posterior view.
34 Neurovasculature
Proper
plantar
digital
nn.
Lumbricals
Adductor
hallucis
Common plantar
digital nn.
Flexor hallucis
longus tendon
Lateral plantar
n., super­
ficial br.
Muscular brs.
Abductor
digiti minimi
Flexor
digitorum
longus
tendon
Lateral
plantar n.
Fibular com­
municating br.
Sural n.
Abductor
hallucis
Quadratus
plantae
Sciatic n.
Medial
sural
cutaneous
n.
Medial
plantar n.
Flexor
digitorum
brevis and
plantar
aponeurosis
Sacro­
tuberous
lig.
Lateral dorsal
cutaneous n.
Medial
calcaneal
brs.
Lateral calcaneal
brs.
Proper plantar
digital nn.
Tibial n.
Muscular brs.
Biceps femoris,
long head
Semi­
tendinosus
Semi­
membranosus
Adductor
magnus,
medial part
Biceps femoris,
short head
B
Right foot, plantar view.
Table 34.7
Nerve
Innervated muscles
Sensory branches
Direct brs. from
sciatic n.
Semitendinosus
Semimembranosus
Biceps femoris (long head)
Adductor magnus (medial part)
—
Tibial n.
Triceps surae
Plantaris
Popliteus
Tibialis posterior
Flexor digitorum longus
Flexor hallucis longus
Medial sural cutaneous n.
Medial and lateral
calcaneal brs.
Lateral dorsal cutaneous n.
Medial
plantar n.
Adductor hallucis
Flexor digitorum brevis
Flexor hallucis brevis (medial
head)
1st lumbricals
Proper plantar digital nn.
Lateral
plantar n.
Flexor hallucis brevis (lateral
head)
Quadratus plantae
Abductor digiti minimi
Flexor digiti minimi brevis
Opponens digiti minimi
2nd to 4th lumbricals
1st to 3rd plantar interossei
1st to 4th dorsal interossei
Adductor hallucis
Proper plantar digital nn.
Tibial n.
Popliteal fossa
Gastrocnemius
Soleus
Deep flexors
Deep flexor
tendons
Tibial n. (in
malleolar canal)
A
Posterior view.
Lateral
malleolus
Tibial nerve (L4–S3)
485
Lower Limb
Superficial Nerves & Veins of the Lower Limb
Fig. 34.26 Superficial cutaneous veins and nerves
of right lower limb
Inguinal lig.
Superficial
circumflex
iliac v.
Lateral cutaneous
n. of the thigh
Superficial
epigastric v.
Femoral a.
and v. (in
saphenous opening)
Ilioinguinal n.
Superior clunial nn.
Iliohypogastric n.,
lateral cutaneous br.
Middle clunial nn.
Superficial
inguinal ring
External
pudendal vv.
Femoral n.,
anterior femoral
cutaneous brs.
Accessory
saphenous v.
Inferior clunial nn.
(posterior cutaneous
n. of the thigh)
Lateral cutaneous
n. of the thigh
Fascia lata
Great
saphenous v.
Obturator n.
Posterior cutaneous
n. of the thigh
Obturator n.,
cutaneous br.
Saphenous n.,
infrapatellar br.
Saphenous n.
(femoral n.)
Lateral sural
cutaneous n.
(common
fibular n.)
Great
saphenous v.
Saphenous n.
(femoral n.)
Small
saphenous v.
Superficial
fibular n.
Medial sural
cutaneous n.
(tibial n.)
Lateral sural
cutaneous n.
(common fibular n.)
Sural n.
(tibial n.)
Intermediate dorsal
cutaneous n.
Sural n.
(tibial n.)
Medial dorsal
cutaneous n.
Calcaneal brs.
Lateral dorsal
cutaneous n.
(tibial n.)
Deep fibular n.
Medial and lateral
plantar cutaneous brs.
A
Anterior view.
486
B
Posterior view.
Right lower limb.
Iliohypo­
gastric n.
Lateral
cutaneous n.
of the thigh
Obturator n.
Genitofemoral n.
Iliohypogastric n.
Clunial nn.
Ilioinguinal n.
34 Neurovasculature
Fig. 34.27 Cutaneous innervation of the lower limb
Lateral
cutaneous n.
of the thigh
Posterior
cutaneous n.
of the thigh
Femoral n.
Obturator n.
Common
fibular n.
Sciatic n.
Femoral n.
Tibial n.
Common
fibular n.
Sciatic n.
Tibial n.
B
Posterior view.
Anterior view.
A
Fig. 34.28 Dermatomes of the lower limb
Right lower limb.
T11
L2
T12
L1
L3
S2
S5
L2
S4
L3
S3
L4
L5
S2
S1
L4
L5
L4
S1
Anterior view.
A
L5
Posterior view.
B
487
Lower Limb
Topography of the Inguinal Region
Fig. 34.29 Superficial veins and lymph nodes
Right male inguinal region, anterior view. Removed: Cribriform fascia
over the saphenous opening.
Superficial and superolateral
inguinal l.n.
Inguinal
lig.
External
iliac v.
External iliac
l.n.
Superficial circum­
flex iliac v.
Rosenmüller’s
l.n.
Superficial
epigastric v.
External
pudendal v.
Superficial and
superomedial
inguinal l.n.
Saphenous
opening
Femoral a.
and v.
Deep inguinal
l.n.
Anterior femoral
cutaneous v.
Superficial and
inferior inguinal
l.n.
Great
saphenous v.
Fig. 34.30 Inguinal region
Right male inguinal region, anterior view.
Linea alba
External oblique
Arcuate line
Internal oblique
Rectus
abdominis
Transversus
abdominis
Lateral cutaneous n.
of the thigh
Anterior rectus
sheath
Superficial circumflex
iliac a. and v.
Inguinal lig.
Superficial
abdominal fascia
Genitofemoral n.,
femoral br.
External oblique
aponeurosis
Superficial
inguinal
ring
Ilioinguinal n.
Genitofemoral
n., genital br.
Reflected inguinal
lig.
Spermatic cord (cut)
Femoral a. and v.
(deep to saphenous
opening)
Lacunar lig.
Saphenous opening
in fascia lata
External
pudendal a. and v.
Anterior
femoral
cutaneous v.
488
Great saphenous v.
Pectineus, deep
to fascia lata
Region
Anterior
superior
iliac spine
Structures in the inguinal region
Boundaries
Contents
Retro-inguinal space
①
②
Iliopectineal
arch
③
Reflected inguinal
lig.
Iliopubic
eminence
Pubic tubercle
Lacunar lig.
① Muscular
compartment
Anterior superior iliac
spine
Inguinal lig.
Iliopectineal arch
Femoral n.
Lateral cutaneous n. of the thigh
Iliacus
Psoas major
②V
ascular
compartment
Inguinal lig.
Iliopectineal arch
Lacunar lig.
Femoral a. and v.
Genitofemoral n., femoral br.
Rosenmüller’s lymph node
Medial crus
Lateral crus
Reflected inguinal lig.
Ilioinguinal n.
Genitofemoral n., genital br.
Spermatic cord
34 Neurovasculature
Table 34.8
Ilioinguinal lig.
Inguinal canal
③ Superficial
inguinal ring
Fig. 34.31 Retro-inguinal space:
Muscular and vascular compartments
Right inguinal region, anterior view.
External
oblique
Lateral cutaneous
n. of the thigh
External oblique
aponeurosis
Inguinal lig.
Muscular
compartment
Femoral n.
Iliacus
Iliopsoas
Intercrural fibers
Psoas major
Medial crus
Iliopectineal bursa
Lateral crus
Superficial
inguinal ring
Iliopectineal arch
Reflected inguinal lig.
Acetabular fossa
Femoral ring
Lacunar lig.
Genitofemoral n.,
femoral br.
Vascular
compartment
Pubic symphysis
Femoral a. and v.
Rosenmüller’s l.n.
Ischial spine
Ischial tuberosity
489
Lower Limb
Topography of the Gluteal Region
Fig. 34.32 Gluteal region
Right gluteal region, posterior view.
Gluteal fascia
(gluteus medius)
Gluteal fascia
(gluteus maximus)
Gluteus
maximus
Gluteus medius
Superior gluteal
a., v., and n.
Inferior gluteal
a., v., and n.
Gluteal sulcus Fascia lata
A
Fasciae and cutaneous neurovasculature.
Posterior cutaneous
n. of the thigh
Pudendal n.,
perineal brs.
Obturator internus
Sacrotuberous lig.
Ischial tuberosity
Posterior cutaneous
n. of the thigh,
perineal brs.
Superior
clunial nn.
Iliohypogastric n.,
lateral br.
Gluteal fascia
(gluteus medius)
Middle
clunial nn.
Gluteus
maximus
Inferior
clunial nn.
Adductor
magnus
Posterior cutaneous
n. of the thigh
(with biceps femoris
long head)
Semi­
membranosus
Semitendinosus
B
Gluteal region. Removed: Fascia lata.
490
Piriformis
Gemellus superior
and inferior
Obturator
internus
Sciatic n.
(with a.)
Quadratus
femoris
Gluteus maximus
Adductor magnus
Adductor magnus
Gracilis
Posterior cutaneous
n. of the thigh
C
Deep gluteal region. Partially removed: Gluteus maximus.
Table 34.9
Sciatic foramina
Posterior
superior
iliac spine
Anterior superior
iliac spine
A
Piriformis
Greater
sciatic
foramen
① Suprapiriform
portion
Superior gluteal a.,
v., and n.
② Infrapiriform
portion
Inferior gluteal a., v.,
and n.
Internal pudendal a.
and v.
Pudendal n.
Sciatic n.
Posterior cutaneous
n. of the thigh
S
Sacro­
spinous
lig.
Sacro­
tuberous
lig.
Greater sciatic
notch
D
③ Lesser sciatic foramen
Internal pudendal a.
and v.
Pudendal n.
Obturator internus
Boundaries
Greater sciatic notch
Sacrospinous lig.
Sacrum
34 Neurovasculature
Transmitted
structures
Foramen
Lesser sciatic notch
Sacrospinous lig.
Sacrotuberous lig.
Lesser sciatic
notch
Fig. 34.33 Gluteal region and
­ischioanal fossa
Right gluteal region, posterior view.
Removed: Gluteus maximus and medius.
Anterior superior
iliac spine
Gluteus
minimus
Posterior superior
iliac spine
Tensor fasciae
latae
Superior gluteal
a. and n.
Piriformis
Inferior gluteal n.
Gemellus
superior
Inferior gluteal
aa. and vv.
Obturator
internus
Pudendal n.
Gemellus
inferior
Internal pudendal
a. and v.
Br. of medial
circumflex
femoral a.
Obturator
internus
Trochanteric
bursa
Pudendal (Alcock’s)
canal
Quadratus
femoris
Sacrotuberous lig.
Adductor
magnus
Sciatic n.
Gracilis
Adductor
magnus
1st perforating a.
Semitendinosus
Semi­
membranosus
Biceps femoris,
long head
Posterior cutaneous
n. of the thigh
491
Topography of the Anterior, Medial & Posterior Thigh
Fig. 34.34 Anterior and medial thigh
Lower Limb
Anterior superior Inguinal Superficial
epigastric a.
iliac spine
lig.
Right thigh, anterior view.
Superficial
circumflex
iliac a.
External oblique
aponeurosis
Tensor
fasciae latae
Iliopsoas
Femoral n.
External pudendal a.
Femoral a. and v.
Spermatic
cord
Pectineus
Deep a.
of thigh
Sartorius
Adductor
longus
Gracilis
Rectus femoris
External iliac
a. and v.
Inguinal lig.
Lateral cutaneous
n. of the thigh
Sartorius
Iliotibial tract
Femoral
a. and v.
in adductor
canal
Femoral n.
Sacral plexus
Femoral a. and v.
Rectus femoris
Lateral circumflex
femoral a.,
ascending br.
Deep a.
of thigh
Quadriceps
femoris
Superior and inferior
gluteal aa.
Medial circumflex
femoral a.
Pectineus
Obturator n.
Adductor brevis
Perforating aa.
Lateral circumflex
femoral a.,
descending br.
Fascia lata
Adductor longus
Adductor magnus
Patellar vascular
network
Descending
genicular a.
A
Femoral triangle. Removed: Skin, subcutaneous tissue,
and fascia lata. Partially transparent: Sartorius.
Vastus
intermedius
Rectus
femoris
Vastus
medialis
Vastus
lateralis
Femoral a. and v.,
saphenous n. (in
adductor canal)
Obturator n.,
cutaneous br.
Sartorius
Saphenous n.
B
Neurovasculature of the anterior thigh. Removed: Anterior abdominal
wall. Partially removed: Sartorius, rectus femoris, adductor longus,
and pectineus.
492
34 Neurovasculature
Fig. 34.35 Posterior thigh
Right thigh, posterior view.
Superior
clunial nn.
Iliohypo­
gastric n.,
lateral br.
Gluteal fascia
(gluteus
medius)
Middle
clunial
nn.
Gluteus
maximus
Inferior
clunial
nn.
Adductor
magnus
Posterior
cutaneous
n. of the thigh
Fascia lata,
iliotibial tract
Gluteus
maximus
Gluteus
medius
Superior
gluteal a., v.,
and n.
Gluteus
minimus
Inferior
gluteal n.
Piriformis
Pudendal n.
Medial circumflex
femoral a.
Inferior
gluteal a.
Trochanteric
bursa
Sacrotuberous
lig.
Gluteus
maximus
Posterior
cutaneous n.
of the thigh
Quadratus
femoris
Sciatic n.
(with a.)
Obturator
internus
1st perforating a.
Adductor
magnus
Biceps femoris,
long head
Biceps femoris,
long head
Adductor
magnus
2nd perforating a.
Popliteal
a. and v.
Tibial n.
Common
fibular n.
Lateral sural
cutaneous n.
Sural n.
Gracilis
Semi­
tendinosus
3rd perforating a.
Adductor
hiatus
Biceps femoris,
short head
Iliotibial tract
Popliteal a. and v.
Common
fibular n.
Semi­
membranosus
Gluteal region and thigh. Removed: Fascia lata.
A
Biceps femoris,
long head
Tibial n.
Plantaris
Medial sural
cutaneous n.
Lateral sural
cutaneous n.
Gastrocnemius
Neurovasculature of the posterior thigh. Partially removed: Gluteus maxi­
B
mus, gluteus medius, and biceps femoris. Retracted: Semimembranosus.
493
Lower Limb
Topography of the Posterior Compartment of the Leg & Foot
Fig. 34.36 Posterior compartment of leg
Right leg, posterior view.
Semi­
tendinosus
Semi­
membranosus
Tibial n.
Semi­
tendinosus
Biceps
femoris
Plantaris
Common
fibular n.
Gracilis
Semi­
membranosus
Tibial n.
Gastroc­
nemius
Lateral sural
cutaneous n.
Plantaris
Common
fibular n.
Popliteus
Popliteal a.
and v.
Medial sural
cutaneous n.
Great
saphenous v.
Biceps
femoris
Tendinous arch
of soleus
Soleus
Gastrocnemius,
lateral head
Deep fascia
of the leg
Small
saphenous v.
Gastrocnemius,
medial head
Communi­
cating br.
Posterior tibial a.
Tibial n.
Fibular a.
Flexor digitorum
longus
Tibialis
posterior
Saphenous n.
Sural n.
Flexor hallucis
longus
Medial malleolus
Fibularis
brevis
Perforating
br.
Communi­
cating br.
Fibular a.
Fibularis longus
Lateral malleolus
Tibial n.,
medial
calcaneal br.
A
Superficial neurovascular structures.
494
Dorsal cutaneous n.
of the foot
Flexor
retinaculum
Calcaneal
(Achilles’) tendon
Calcaneal rete
B
Deep neurovascular structures. Removed:
Gastrocnemius. Windowed: Soleus.
Fig. 34.37 Popliteal region
Right leg, posterior view.
Sciatic n.
Biceps femoris,
long head
Gracilis
Biceps
femoris,
short head
Semi­
membranosus
Semi­
tendinosus
Deep popliteal l. n.
Popliteal a.
and v.
Common
fibular n.
Gastrocnemius,
medial head
Biceps
femoris
Semi­
membranosus
Plantaris
Gastroc­
nemius
Small
saphenous v.
Medial superior
genicular a.
Medial
subtendinous
bursa of
gastrocnemius
34 Neurovasculature
Popliteal
a. and v.
Lateral superior
genicular a.
Plantaris
Middle genicular a.
Gastroc­
nemius,
lateral head
Semimembranosus
bursa
Oblique popliteal
lig.
Lateral inferior
genicular a.
Semimembranosus
tendon
Posterior tibial
recurrent a.
Medial inferior
genicular a.
B
Deep lymph nodes.
Fig. 34.38 Ankle region
Right ankle, medial view.
Plantaris
tendon
Fibularis
group
Tibial n.
Fibula
Deep flexors
Superficial
flexors
Extensor
group
Soleus
Popliteus
Gastrocnemius
Tibia
Triceps
surae
A
Deep neurovascular structures.
Tibial n.,
posterior tibial a.
Superior extensor
retinaculum
Medial
malleolar brs.
Medial malleolus
(with subcutaneous bursa)
Tibialis
posterior
Inferior extensor
retinaculum
Flexor digi­
torum longus
Tibialis anterior
Flexor hallucis
longus
Medial
tarsal aa.
Calcaneal
(Achilles’)
tendon
Extensor hallucis
longus tendon
Medial
calcaneal br.
Medial plantar a.,
superficial br.
Tarsal tunnel
Flexor
retinaculum
Medial plantar
a. and n.
1st metatarsal
Abductor
hallucis
Medial plantar
a. and n.
Lateral plantar
a. and n.
495
Lower Limb
Topography of the Lateral & Anterior Compartments of the Leg & Dorsum
of the Foot
Head of
fibula
Fig. 34.39 Neurovasculature of the lateral
compartment of the leg
Right limb. Removed: Origins of the fibularis longus and extensor
digitorum longus.
Biceps
femoris
Short
head
Tibia
Anterior
intermuscular
septum
Superficial
fibular n.
Iliotibial
tract
Long
head
Common
fibular n.
Lateral sural
cutaneous n.
Transverse
intermuscular
septum
Anterior crural
intermuscular
septum
Table 34.10
Deep fibular n.
Compartment
① Anterior compartment
③ Superficial
part
Sural n.
Posterior
compartment
496
Extensor hallucis
longus
Fibularis longus
Fibularis brevis
Triceps surae (gastrocnemius and soleus)
Neurovascular
contents
Deep fibular n.
Anterior tibial a.
and v.
Intermediate
dorsal
cutaneous n.
Deep
fibular n.,
cutaneous
br.
Superficial fibular n.
—
Plantaris
Flexor digitorum
longus
Flexor hallucis longus
Deep fascia
of the leg
Lateral dorsal
cutaneous n.
Extensor digitorum
longus
Tibialis posterior
④ Deep part
Superficial
fibular n.
Lateral
malleolus
Deep fascia
of the leg
Fibularis tertius
Extensor
digitorum
longus
Medial dorsal
cutaneous n.
Sural n., small
saphenous v.
Muscular contents
② Lateral compartment
Soleus
Tibial n.,
posterior tibial
a. and v.
Compartments of the leg
Tibialis
anterior
Commu­
nicating br.
F
Tibialis anterior
Fibularis
longus
Medial sural
cutaneous
n. (tibial n.)
Saphenous n.,
great
saphenous v.
Interosseous
membrane
D
Fibular a.
and v.
Superficial
fibular n.
Gastroc­
nemius
Lateral
calcaneal brs.
S
Posterior
intermuscular
septum
Lateral tibial
condyle
Head of fibula
A
Fibula
Patella
Deep fibular n.,
anterior tibial
a. and v.
Tibial n.
Posterior tibial a.
and v.
Fibular a. and v.
Fig. 34.40 Neurovasculature of the anterior
compartment of the leg and foot
Clinical box 34.5
Right limb with foot in plantar flexion.
Muscle edema or hematoma can lead to a rise in tissue fluid pressure in
the compartments of the leg. Subsequent compression of neurovascular
structures due to this increased pressure may cause ischemia
and irreversible muscle and nerve damage. Patients with anterior
compartment syndrome, the most common form, suffer excruciating
pain and cannot dorsiflex the toes. Emergency incision of the fascia of the
leg may be performed to relieve compression.
Patella
Head of fibula
Patellar lig.
Pes anserinus
(common insertion
of sartorius,
gracilis, and
semitendinosus)
34 Neurovasculature
Compartment syndrome
Gastrocnemius
Fibularis longus
Fibula
Tibia
Fibular a.,
perforating br.
Extensor
hallucis longus
Anterior
lateral
malleolar a.
Tibialis anterior
tendon
Deep
fibular n.
Lateral br.
of deep
fibular n.
Extensor
hallucis brevis
Extensor
digitorum
brevis
Lateral
tarsal a.
Medial br. of
deep fibular n.
Dorsalis
pedis a.
Arcuate a.
Dorsal
interossei
Deep
plantar a.
Dorsal
meta­
tarsal aa.
Extensors
hallucis longus
and brevis
tendons
Extensors
digitorum
longus and
brevis
tendons
Dorsal
digital nn.
Muscular brs.
Deep fibular n.
Extensor
hallucis longus
Extensor
digitorum longus
Anterior
tibial a.
Tibialis
anterior
Anterior tibial
a. and v.
Soleus
Superficial
fibular n.
Fibularis brevis
Inferior extensor
retinaculum
Lateral dorsal
cutaneous n.
Intermediate
dorsal
cutaneous n.
Medial dorsal
cutaneous n.
Dorsal
metatarsal aa.
Superior extensor
retinaculum
Medial malleolus
Dorsalis pedis a.
Extensor
hallucis brevis
Extensor
hallucis longus
tendon
Deep fibular n.
Deep fibular n.,
cutaneous br.
B
Neurovasculature of the leg. Removed:
Skin, subcutaneous tissue, and fasciae.
Retracted: Tibialis anterior and extensor
hallucis longus.
Dorsal
digital aa.
A
Neurovasculature of the dorsum of the foot.
497
Lower Limb
Topography of the Sole of the Foot
Fig. 34.41 Neurovasculature of the sole of the foot
Right foot, plantar view.
Proper plantar
digital aa.
Proper plantar
digital nn.
Common
plantar
digital nn.
Medial
plantar n.
Lateral
plantar a.
Medial plantar
a., super­
ficial br.
Plantar
aponeurosis
Lateral
plantar n.,
superficial brs.
Lateral
plantar sulcus
Medial plantar
a., deep br.
Medial plantar
n., super­
ficial br.
Medial plantar
sulcus
Abductor
hallucis
Proper plantar
digital aa.
and nn.
Flexor digi­
torum brevis
tendons
Plantar
metatarsal aa.
Lateral plantar
n., super­
ficial br.
A
Superficial layer. Removed: Skin, subcutane­
ous tissue, and fascia.
Lateral
plantar n.,
deep br.
Quadratus
plantae
Lateral plantar
a., v., and n.
Abductor
digiti minimi
Flexor
digitorum
brevis
B
Middle layer. Removed: Plantar aponeurosis
and flexor digitorum brevis.
498
Flexor hallucis
longus
tendon
Common
plantar
digital nn.
Medial plantar
a., super­
ficial br.
Medial plantar
a., deep br.
Flexor digi­
torum longus
tendon
Medial
plantar n.
Abductor
hallucis
Plantar
aponeurosis
34 Neurovasculature
Proper plantar
digital aa. and nn.
Flexor digitorum
longus tendons
Flexor digitorum
brevis tendons
Lumbricals
Transverse
head
Plantar
interossei
Adductor
hallucis
Oblique
head
Plantar metatarsal
aa.
Flexor hallucis brevis
Deep
plantar arch
Medial plantar
a., deep br.
Lateral
plantar n.,
deep br.
Flexor hallucis
longus tendon
Quadratus
plantae
Medial
plantar a.
Medial
plantar n.
Lateral plantar
a., v., and n.
Abductor
hallucis
Flexor
digitorum
brevis
Plantar
aponeurosis
C
Deep layer. Removed: Flexor digitorum
longus. Windowed: Adductor hallucis
(oblique head).
Extensor
digitorum longus
Fig. 34.42 Neurovasculature of
the foot: Cross section
Coronal section, distal view.
Intermediate
dorsal cuta­
Extensor
neous n.
digitorum longus
Interossei
3rd metatarsal
Deep fibular n.,
dorsal pedal a.
Extensor
hallucis brevis
Extensor
digitorum longus
Extensor
hallucis longus
Lateral dorsal
cutaneous n.
Medial dorsal
cutaneous n.
Dorsal meta­
tarsal a.
2nd metatarsal
Medial cuneiform
Abductor
digiti minimi
Tibialis anterior
Opponens
digiti minimi
Deep layer of
plantar fascia
Flexor digiti
minimi brevis
Saphenous n.,
cutaneous br.
Lateral plantar
a. and v.
Abductor
hallucis
Lateral
plantar septum
Lateral plantar
n., deep br.
Lateral plantar n.,
superficial br.
Quadratus
plantae
Fibularis
longus
Aponeurosis
of flexor
digitorum longus
Flexor hallucis
brevis
Plantar
aponeurosis
Flexor
digitorum brevis
Medial plantar
a. and n.
Deep
plantar arch
Flexor hallucis longus
Medial plantar
septum
499
35
Sectional & Radiographic Anatomy
Lower Limb
Sectional Anatomy of the Lower Limb
Fig. 35.1 Windowed dissection of the thigh and leg
Right limb, posterior view.
Iliac crest
Gluteus
minimus
Gluteus
maximus
Gluteus
medius
Piriformis
Gemellus
superior
Tensor
fasciae latae
Obturator
internus
Gluteus
maximus
Gemellus
inferior
Quadratus
femoris
Ischial
tuberosity
Adductor
magnus
Gracilis
Adductor
magnus
Iliotibial
tract
Semitendinosus
Femur
Biceps femoris,
long head
Rectus
femoris
Vastus medialis
Vastus
intermedius
Sartorius
Vastus
lateralis
Gracilis
Adductor longus
Biceps
femoris,
short head
Adductor brevis
Sciatic nerve
Gracilis
Semitendinosus
Semimembranosus
Iliotibial
tract
Biceps
femoris,
long head
Plantaris
Gastrocnemius
Tibia
Soleus
Fibula
Interosseous
membrane
Triceps
surae
Calcaneal
(Achilles’) tendon
500
Right limb, proximal view.
Quadriceps femoris
Vastus
medialis
Vastus
intermedius
Rectus
femoris
Vastus
lateralis
Medial
intermuscular
septum
Femur
Sartorius
Femoral
artery
and vein
Iliotibial
tract
Adductor
longus
35 Sectional & Radiographic Anatomy
Fig. 35.2 Cross-section through the thigh and leg
Sciatic
nerve
Adductor
brevis
Lateral
intermuscular
septum
Gracilis
Biceps femoris,
short head
Adductor
magnus
Semimembranosus
Semitendinosus
Biceps femoris,
long head
A
Thigh (plane of upper section in Fig. 35.1A)
Deep
fibular nerve
Tibialis
anterior
Extensor
hallucis longus
Extensor
digitorum longus
Tibia
Anterior tibial
artery and vein
Anterior
intermuscular
septum
Interosseous
membrane
Fibularis
brevis
Tibialis
posterior
Fibularis
longus
Flexor
digitorum
longus
Posterior intermuscular
septum
Tibial nerve
Fibula
Plantaris
tendon
Soleus
Posterior tibial
artery and vein
Transverse
Flexor
intermuscular
hallucis longus
septum
Gastrocnemius,
Gastrocnemius,
lateral head
medial head
B
Leg (plane of lower section in Fig. 35.1B)
501
Lower Limb
Radiographic Anatomy of the Lower Limb (I)
Fig. 35.3 MRI of the thigh
Sartorius
Transverse section, distal
(inferior) view.
Rectus femoris
Circumflex femoral a. and v.
Femoral a., v., and n.
Adductor longus
Deep femoral a. and v.
Tensor fasciae latae
A
B
C
Pectineus
Vastus lateralis
Iliotibial tract
Femur
Adductor magnus
Sciatic n.
Lateral femoral
intermuscular septum
A
Proximal thigh. (Reproduced
from Moeller TB, Reif E. Pocket
Atlas of Sectional Anatomy,
Vol 2, 4th ed. New York, NY:
Thieme; 2014.)
Gluteus maximus
Rectus femoris
Vastus lateralis
Vastus medialis
Sartorius
Great saphenous v.
Vastus intermedius
Femoral a. and v.
Femur
Sciatic n.
B
Mid-thigh. (Reproduced from
Moeller TB, Reif E. Atlas of Sectional Anatomy: The Musculoskeletal System. New York, NY:
Thieme; 2009.)
Biceps femoris,
long head
Adductor longus
Gracilis
Adductor magnus
Semimembranous
Semitendinous
Rectus femoris, tendon
Vastus intermedius
Vastus medialis
Femur
Vastus lateralis
Biceps femoris, short head
Perforating a. and v. of
deep a. and v. of thigh
C
Distal thigh. (Reproduced
from Moeller TB, Reif E.
Pocket Atlas of Sectional
Anatomy, Vol 2, 4th ed.
New York, NY: Thieme;
2014.)
502
Common fibular n.
Tibial n.
Biceps femoris, long head
Sartorius
Femoral a. and v.
Gracilis
Semimembranosus
Semitendinosus
Fig. 35.4 MRI of the leg
Transverse section, distal
(inferior) view.
Tibia
Tibial tuberosity
Sartorius, tendon
Extensor digitorum
longus
Gracilis, tendon
A
Semitendinosus, tendon
B
Popliteus
Common fibular n.
Popliteal a. and v.
C
Tibial n.
Gastrocnemius, lateral head
Gastrocnemius, medial head
A
Proximal leg. (Reproduced from
Moeller TB, Reif E. Pocket Atlas
of Sectional Anatomy, Vol 2,
4th ed. New York, NY: Thieme;
2014.)
Tibialis anterior
Extensor halluces
longus
Tibia
Extensor digitorum
longus
Tibialis posterior
Deep
fibular n.
Flexor digitorum
longus
Anterior tibial
a. and v.
Posterior tibial
a. and v.
Interosseous
membrane
Tibial n.
Fibularis brevis
B
Mid-leg. (Reproduced from
Moeller TB, Reif E. Atlas of
Sectional Anatomy: The
Musculoskeletal System.
New York, NY: Thieme;
2009.)
35 Sectional & Radiographic Anatomy
Anterior tibial muscle
Fibular a. and v.
Fibula
Flexor hallucis longus
Soleus
Extensor hallucis longus
Anterior tibial a. and v.
Great saphenous v.
Extensor digitorum longus
Tibia
Tibialis posterior, tendon
Fibula
Fibularis longus, tendon
C
Distal leg. (Reproduced from
Moeller TB, Reif E. Pocket Atlas
of Sectional Anatomy, Vol 2,
4th ed. New York, NY: Thieme;
2014.)
Fibularis brevis
Sural n.
Small saphenous v.
Tibial n.
Flexor hallucis longus
Soleus muscle
Tendons of triceps surae
and plantaris
503
Lower Limb
Radiographic Anatomy of the Lower Limb (II)
Fig. 35.5 Radiograph of the right
hip joint
Anteroposterior view.
Anterior acetabular rim
Roof of the acetabulum
Posterior acetabular rim
Fovea of the femoral head
Femoral head
Greater trochanter
Köhler’s teardrop figure
Femoral neck
Superior pubic ramus
Intertrochanteric crest
Obturator foramen
Ischial tuberosity
Lesser trochanter
Fig. 35.6 Radiograph of right hip joint with
limb abducted laterally (Lauenstein view)
(Reproduced from Moeller TB, Reif E. Pocket Atlas
of Radiographic Anatomy, 3rd ed. New York, NY:
Thieme; 2010.)
Anterior superior iliac spine
Sacroiliac joint
Superior acetabular rim
Anterior acetabular rim
Femoral neck
Pubic bone
Greater trochanter
Ischium
Lesser trochanter
Superior pubic ramus
Inferior pubic ramus
Femoral head
504
Ischial tuberosity
Fig. 35.7 MRI of the right hip joint
Sartorius
Iliopsoas
Tensor fascia lata
Head of femur
Gluteus medius
Femoral a., v., and n.
Urinary bladder
Pubis, superior ramus
Obturator a., v., and n.
Levator ani
Obturator internus
Sciatic n.
Ischium
Gluteus maximus
Fig. 35.8 MRI of the hip joints
35 Sectional & Radiographic Anatomy
Transverse section, distal (inferior) view.
(Reproduced from Moeller TB, Reif E. Atlas
of Sectional Anatomy: The Musculoskeletal
System. New York, NY: Thieme; 2009.)
L4 vertebra
Coronal section, anterior view. (Reproduced from Moeller TB, Reif E. Atlas of
Sectional Anatomy: The Musculoskeletal
System. New York, NY: Thieme; 2009.)
Psoas
Iliacus
Urinary bladder
Gluteus medius
Head of femur
Iliotibial tract
Hip joint
Obturator internus
Greater trochanter
Obturator externus
Gracilis
Adductor longus
Vastus lateralis
Fig. 35.9 MRI of the right hip joint
Sagittal section, medial view. (Reproduced
from Moeller TB, Reif E. Atlas of Sectional
Anatomy: The Musculoskeletal System.
New York, NY: Thieme; 2009.)
Iliopsoas
Ilium (roof of acetabulum)
Gluteus maximus
Hip joint
Femur, head
Lateral circumflex femoris a.
(ascending branch)
Pectineus
Ischium
Sartorius
Deep a. and v. of the thigh
Adductor magnus
Biceps femoris
Vastus medialis
505
Lower Limb
Radiographic Anatomy of the Lower Limb (III)
Fig. 35.10 Radiograph of the right
knee joint
Femur
Anteroposterior view. (Reproduced courtesy
of Klinik für Diagnostische Radiologie, Universitätsklinikum Schleswig Holstein, Campus
Kiel: Prof. Dr. Med. S. Müller-Huelsbeck.)
Patella
Lateral femoral epicondyle
Medial femoral epicondyle
Medial femoral condyle
Lateral femoral condyle
Medial tibial condyle
Lateral tibial condyle
Medial and lateral tubercles
of intercondylar eminence
Epiphyseal plate
Fibular head
Tibia
Fibula
Cortex
Fig. 35.11 Radiograph of the knee in flexion
Patellofemoral
joint
(Reproduced courtesy of Klinik für Diagnostische Radiologie,
Universitätsklinikum Schleswig Holstein, Campus Kiel: Prof.
Dr. Med. S. Müller-Huelsbeck.)
Patella
Femur
Patella
Lateral femoral
condyle
Medial femoral
condyle
Tibial plateau
Fibular head
Tibial tuberosity
Lateral femoral
condyle
A Lateral view.
506
B Sunrise view.
Intercondylar
fossa
Medial femoral
condyle
Fig. 35.12 MRI of the knee joint
Patellar
lig.
Lateral femoral
condyle
Medial collateral lig.
Lateral
collateral lig.
Medial femoral
condyle
Anterior
cruciate lig.
Biceps femoris
Posterior cruciate lig.
Popliteal a. and v.
Gastrocnemius,
lateral head
A
Transverse section,
distal (inferior) view.
Gastrocnemius,
medial head
Tibial n.
Anterior
cruciate lig.
Lateral
epicondyle
Posterior
cruciate lig.
Medial
collateral lig.
Lateral femoral
condyle
Medial femoral
condyle
Lateral meniscus,
intermediate
portion
Medial meniscus,
intermediate
portion
Lateral tibial
condyle
Fibula,
head
B Coronal section.
35 Sectional & Radiographic Anatomy
(Reproduced from Moeller TB, Reif E. Atlas
of Sectional Anatomy: The Musculoskeletal
System. New York, NY: Thieme; 2009.)
Medial intercondylar
tubercle
Fig. 35.13 MRI of the knee joint
Medial tibial
condyle
Quadriceps
tendon
Sagittal section. (Reproduced from Moeller TB, Reif E. Atlas of Sectional
Anatomy: The Musculoskeletal System. New York, NY: Thieme; 2009.)
Popliteal a.
Popliteal v.
Vastus lateralis
Biceps femoris
Patella
Gastrocnemius,
lateral head
Femur,
lateral condyle
A
B
Lateral meniscus,
posterior horn
Anterior
cruciate lig.
Patellar lig.
Tibiofibular joint
Fibula, head
A
Lateral meniscus,
anterior horn
Lateral tibial
condyle
B
Infrapatellar
fat pad
Posterior
cruciate lig.
507
Lower Limb
Radiographic Anatomy of the Lower Limb (IV)
Fig. 35.14 Radiograph of the ankle
(Reproduced from Moeller TB, Reif E. Taschenatlas der
Roentgenanatomie, 2nd ed. Stuttgart: Thieme; 1998.)
Fibula
Tibia
Tibia
Fibula
Growth plate
Talocrural joint
Medial
malleolus
Growth
plate
Fibular
notch
Talocrural
joint
Medial
malleolus
Lateral
malleolus
Trochlea
of talus
Calcaneus
Subtalar
joint
Navicular
A Anteroposterior view.
Trochlea of talus
Talus
Lateral malleolus
Talonavicular
joint
Sinus tarsi
Navicular
Posterior
tuberosity
of calcaneus
Cuboid
B Left lateral view.
Fig. 35.15 Anterior-posterior view of the forefoot
Distal phalanx
Distal phalanx
Middle phalanx
Proximal phalanx
Distal
interphalangeal joint
Proximal phalanx
Proximal
interphalangeal joint
Metatarsophalangeal
joint
Sesamoids
Metatarsals
Lateral cuneiform
Metatarsophalangeal
joint
Base of 5th
metatarsal
Cuboid
Calcaneocuboid joint
508
Medial cuneiform
Intermediate cuneiform
Intertarsal joint
Navicular
Talocalcaneonavicular
joint
Fig. 35.16 MRI of the right ankle
Tibia
Fibula
Talocrural joint
Talus
Deltoid lig. (posterior tibiotalar part)
Talofibular joint
Subtalar joint
Posterior talofibular lig.
Calcaneofibular joint
Fibularis longus tendon
Medial plantar a., v., and n.
Calcaneus
Abductor hallucis
Flexor digitorum brevis
Plantar aponeurosis
Fig. 35.17 MRI of the right foot
Coronal section, anterior (distal) view.
(Reproduced from Moeller TB, Reif E.
Atlas of Sectional Anatomy: The Musculoskeletal System. New York, NY: Thieme;
2009.)
35 Sectional & Radiographic Anatomy
Coronal section, anterior view. (Reproduced
from Moeller TB, Reif E. Atlas of Sectional
Anatomy: The Musculoskeletal System. New
York, NY: Thieme; 2009.)
Dorsal
Intermediate
cuneiform
Lateral cuneiform
Medial cuneiform
Metatarsal II (base)
Abductor hallucis
Metatarsal III (base)
Metatarsal IV (base)
Metatarsal V (base)
Flexor digitorum
brevis
Interosseous mm.
Abductor digiti minimi
Fig. 35.18 MRI of the right foot
and ankle
Talonavicular
joint
Talocalcaneal
interosseous lig.
Talus
Tibia
Talocrural
joint
Calcaneal (Achilles)
tendon)
Sagittal section. (Reproduced from
Moeller TB, Reif E. Atlas of Sectional
Anatomy: The Musculoskeletal System.
New York, NY: Thieme; 2009.)
Subtalar joint
Navicular
Medial
cuneiform
Calcaneous
Plantar
calcaneonavicular
lig.
Proximal,
middle, and
distal phalanx
of second toe
Plantar
aponeurosis
Metatarsal II,
head
Adductor
hallucis
Intermediate
cuneiform
Quadratus
plantae
509
Head & Neck
36 Surface Anatomy
Surface Anatomy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 512
37 Neck
Muscle Facts (I) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Muscle Facts (II) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Muscle Facts (III) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Arteries & Veins of the Neck . . . . . . . . . . . . . . . . . . . . . . . . . .
Lymphatics of the Neck . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Innervation of the Neck . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Larynx: Cartilage & Structure . . . . . . . . . . . . . . . . . . . . . . . . .
Larynx: Muscles & Levels . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Neurovasculature of the Larynx, Thyroid & Parathyroids . . .
Topography of the Neck: Regions & Fascia . . . . . . . . . . . . . .
Topography of the Anterior Cervical Region . . . . . . . . . . . . .
Topography of the Anterior & Lateral Cervical Regions . . . .
Topography of the Lateral Cervical Region . . . . . . . . . . . . . .
Topography of the Posterior Cervical Region . . . . . . . . . . . .
514
516
518
520
522
524
526
528
530
532
534
536
538
540
38 Bones of the Head
Anterior & Lateral Skull . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Posterior Skull & Calvaria . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Base of the Skull . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Neurovascular Pathways Exiting or Entering
the Cranial Cavity. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Ethmoid & Sphenoid Bones . . . . . . . . . . . . . . . . . . . . . . . . . .
542
544
546
548
550
39 Muscles of the Skull & Face
Muscles of Facial Expression & of Mastication . . . . . . . . . . . .
Muscle Origins & Insertions on the Skull . . . . . . . . . . . . . . . .
Muscle Facts (I) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Muscle Facts (II) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
552
554
556
558
40 Cranial Nerves
Cranial Nerves: Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CN I & II: Olfactory & Optic Nerves . . . . . . . . . . . . . . . . . . . .
CN III, IV & VI: Oculomotor, Trochlear & Abducent Nerves . . .
CN V: Trigeminal Nerve . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CN VII: Facial Nerve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CN VIII: Vestibulocochlear Nerve . . . . . . . . . . . . . . . . . . . . . .
CN IX: Glossopharyngeal Nerve . . . . . . . . . . . . . . . . . . . . . . .
CN X: Vagus Nerve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CN XI & XII: Accessory & Hypoglossal Nerves . . . . . . . . . . . .
Autonomic Innervation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
560
562
564
566
568
570
572
574
576
578
41 Neurovasculature of the Skull & Face
Innervation of the Face . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Arteries of the Head & Neck . . . . . . . . . . . . . . . . . . . . . . . . . .
External Carotid Artery: Anterior, Medial &
Posterior Branches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
External Carotid Artery: Terminal Branches . . . . . . . . . . . . . .
580
582
584
586
Veins of the Head & Neck . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Meninges . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Dural Sinuses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Topography of the Superficial Face . . . . . . . . . . . . . . . . . . . .
Topography of the Parotid Region & Temporal Fossa . . . . . .
Topography of the Infratemporal Fossa . . . . . . . . . . . . . . . . .
Neurovasculature of the Infratemporal Fossa . . . . . . . . . . . .
588
590
592
594
596
598
600
42 Orbit & Eye
Bones of the Orbit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 602
Muscles of the Orbit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .604
Neurovasculature of the Orbit . . . . . . . . . . . . . . . . . . . . . . . . 606
Topography of the Orbit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 608
Orbit & Eyelid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 610
Eyeball . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 612
Cornea, Iris & Lens . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 614
43 Nasal Cavity & Nose
Bones of the Nasal Cavity . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Paranasal Air Sinuses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Neurovasculature of the Nasal Cavity . . . . . . . . . . . . . . . . . .
Pterygopalatine Fossa. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
616
618
620
622
44 Temporal Bone & Ear
Temporal Bone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
External Ear & Auditory Canal . . . . . . . . . . . . . . . . . . . . . . . . .
Middle Ear: Tympanic Cavity . . . . . . . . . . . . . . . . . . . . . . . . .
Middle Ear: Ossicular Chain & Tympanic Membrane . . . . . . .
Arteries of the Middle Ear . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Inner Ear . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
624
626
628
630
632
634
45 Oral Cavity & Pharynx
Bones of the Oral Cavity . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Temporomandibular Joint . . . . . . . . . . . . . . . . . . . . . . . . . . .
Teeth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Oral Cavity Muscle Facts . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Innervation of the Oral Cavity . . . . . . . . . . . . . . . . . . . . . . . .
Tongue . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Topography of the Oral Cavity & Salivary Glands . . . . . . . . .
Tonsils & Pharynx . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Pharyngeal Muscles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Neurovasculature of the Pharynx . . . . . . . . . . . . . . . . . . . . . .
636
638
640
642
644
646
648
650
652
654
46 Sectional & Radiographic Anatomy
Sectional Anatomy of the Head & Neck (I). . . . . . . . . . . . . . .
Sectional Anatomy of the Head & Neck (II) . . . . . . . . . . . . . .
Sectional Anatomy of the Head & Neck (III). . . . . . . . . . . . . .
Sectional Anatomy of the Head & Neck (IV). . . . . . . . . . . . . .
Sectional Anatomy of the Head & Neck (V) . . . . . . . . . . . . . .
Radiographic Anatomy of the Head & Neck (I). . . . . . . . . . . .
Radiographic Anatomy of the Head & Neck (II). . . . . . . . . . .
Radiographic Anatomy of the Head & Neck (III). . . . . . . . . . .
656
658
660
662
664
666
668
670
36
Surface Anatomy
Head & Neck
Surface Anatomy
Fig. 36.1 Regions of the head and neck
Parietal
region
Frontal
region
Orbital
region
Infraorbital
region
Temporal region
Nasal region
Zygomatic region
Oral region
Infratemporal region
Parietal
region
Mental region
Submandibular
triangle
Parotid-masseteric
region
Submental
triangle
Retromandibular region
Anterior
cervical
region
Carotid
triangle
Buccal region
Posterior cervical
region
Temporal
region
Muscular
(omotracheal) triangle
Occipital
region
Sternocleidomastoid
region
Lateral cervical
region
Greater supraclavicular fossa
Lesser supraclavicular fossa
Jugular
fossa
A
Right anterolateral view.
Fig. 36.2 Surface anatomy of the head
and neck
Vertebra
prominens
Frontal bone
Zygomatic
bone
Posterior
cervical region
Right posterolateral view.
B
Supraorbital margin
Infraorbital margin
Philtrum
Helix
Antihelix
Tragus
Antitragus
Commissure of lips
Mental protuberance
Submandibular gland
Mandibular angle
Mandible,
inferior border
Thyroid cartilage
Trapezius
Clavicle
Omohyoid,
inferior belly
Suprasternal
notch
Clavicular Sternal
head
head
A
Right anterolateral view.
Jugular notch
Sternocleidomastoid
Parietal
bone
Occipital bone
External occipital
protuberance
Nuchal lig.
Mastoid
process
Mandibular
angle
Trapezius
Sternocleidomastoid
B
Right posterolateral view.
512
Spinous
process
of C7
36 Surface Anatomy
Fig. 36.3 Palpable bony prominences of the head and neck
Frontal bone
Frontal
notch
Supraorbital
notch
Nasal bone
Zygomatic arch
Infraorbital foramen
Maxilla
Mandibular angle
Mental
protuberance
Mental foramen
Body of
hyoid bone
Superior
thyroid
notch
Laryngeal
prominence
Larynx
Cricoid
cartilage
Clavicle
Manubrium
sterni
Sternoclavicular joint
Parietal bone
Sagittal suture
A
Anterior view.
Lambdoid
suture
Occipital bone
External occipital
protuberance
Temporal bone
Mastoid process
Transverse process
of atlas (C1)
Mandibular
angle
Spinous processes
Scapula,
superior angle
Vertebra
prominens (C7)
B
Posterior view.
513
37
Neck
Head & Neck
Muscle Facts (I)
The bones, joints, and ligaments of the neck and the six topographic
classes of neck muscles are covered here in this unit with the neck, or
in Unit 1 with the back (see Table 37.1). However, some muscles in
the same topographic class belong in different functional classes; for
example, the platysma belongs to the muscles of facial expression; the
Table 37.1
trapezius, to the muscles of the shoulder girdle; and the nuchal muscles, to the intrinsic back muscles. Note that the suboccipital muscles
(short nuchal and craniovertebral joint muscles) are covered with the
lateral (deep) muscles of the neck.
Bones, joints, ligaments, and muscles of the neck
Bones, joints, and ligaments
Bones of the cervical spine
See pp. 8–9
Joints & ligaments of the craniovertebral junction
See pp. 18–19
Joints & ligaments of the cervical spine
See pp. 16–
17, 20-21
Hyoid bone & larynx
Fig. 45.3,
Fig. 37.18
Muscles
I
Superficial neck muscles
III
Platysma, ①, ② sternocleidomastoid, ③, ④, ⑤ trapezius
II
Fig. 37.3
Digastric, geniohyoid, mylohyoid, stylohyoid
Nuchal muscles (intrinsic back muscles)
⑥ Semispinalis capitis
⑦ Semispinalis cervicis
⑧ Splenius capitis
⑨ Splenius cervicis
⑩ Longissimus capitis
⑪ Longissimus cervicis
IV
See p. 34
VI
⑫ Iliocostalis cervicis
Fig. 37.1 Superficial neck muscles
schematic
Fig. 37.6C
Fig. 37.4B
Prevertebral muscles
Longus capitis, longus coli, rectus capitis anterior and
lateralis
See p. 32
Fig. 37.4A
Infrahyoid muscles
Sternohyoid, sternothyroid, thyrohyoid, omohyoid
V
Suboccipital muscles (short nuchal and craniovertebral joint muscles)
Suprahyoid muscles
See p. 31
Fig. 37.6A
Lateral (deep) neck muscles
Anterior, middle, and posterior scalenes
Fig. 37.6B
Fig. 37.2 Nuchal muscles schematic
See Table 37.2 for details.
K
H
S
J
L
A
A
Sternocleidomastoid.
A
Semispinalis.
D
B
Splenius.
Ö
F
Ä
Y
G
B
Trapezius.
514
C
Longissimus.
DIliocostalis.
Fig. 37.3 Superficial neck muscles
37 Neck
Depressor
anguli oris
Sternocleidomastoid
Sternocleidomastoid
Platysma
Trapezius
Trapezius
A
Anterior view.
Clavicular head
Sternal head
B
Left lateral view.
Sternocleidomastoid
Deep layer of nuchal fascia
Trapezius
Descending
part
Rhomboid minor
Levator
scapulae
Transverse
part
Clavicle
Acromion
Scapular spine
Supraspinatus
C
Posterior view. Removed: Trapezius (right side).
Table 37.2
Superficial neck muscles
Muscle
Origin
Insertion
Innervation
Action
Platysma
Skin over lower neck
and upper lateral
thorax
Mandible (inferior
border), skin over lower
face and angle of mouth
Cervical branch of facial
n. (CN VII)
Depresses and wrinkles skin of lower
face and mouth, tenses skin of neck,
aids forced depression of mandible
Motor: Accessory n.
(CN XI)
Unilateral: Tilts head to same side,
rotates head to opposite side
Bilateral: Extends head, aids in
respiration when head is fixed
① Sternal head
Sternocleidomastoid
Trapezius
Sternum (manubrium)
② Clavicular head
Clavicle (medial one
third)
Temporal bone (mastoid
process), occipital bone
(superior nuchal line)
③ Descending part*
Occipital bone, spinous
processes of C1–C7
Clavicle (lateral one
third)
Proprioception: Cervical
plexus (C2, C3, [C4])
Draws scapula obliquely upward,
rotates glenoid cavity superiorly
* The transverse ④ and ascending ⑤ parts are described on p. 320.
515
Head & Neck
Muscle Facts (II)
Suprahyoid muscles
Table 37.3
The suprahyoid muscles are also considered accessory muscles of mastication.
Muscle
Origin
Insertion
1a
Anterior belly
Mandible (digastric fossa)
1b
Posterior belly
Temporal bone (mastoid notch,
medial to mastoid process)
Digastric
② Stylohyoid
Via an intermediate
tendon with a
fibrous loop
Temporal bone (styloid process)
③ Mylohyoid
④ Geniohyoid
Via a split tendon
Hyoid bone
(body)
Mandible (mylohyoid line)
Innervation
Mandible (inferior mental spine)
Mylohyoid n.
(from CN V3)
Facial n.
(CN VII)
Action
Elevates hyoid bone (during swallowing),
assists in opening mandible
Via median tendon
of insertion
(mylohyoid raphe)
Mylohyoid n.
(from CN V3)
Tightens and elevates oral floor, draws
hyoid bone forward (during swallowing),
assists in opening mandible and moving it
side to side (during mastication)
Directly
Anterior ramus
of C1 via
hypoglossal n.
(CN XII)
Draws hyoid bone forward (during
swallowing), assists in opening mandible
Fig. 37.4 Suprahyoid and infrahyoid muscles
S
D
K
1b
G
F 1a
H
A
Suprahyoid muscles, left lateral view.
Table 37.4
B
Infrahyoid muscles, anterior view.
Infrahyoid muscles
Muscle
Origin
Insertion
Innervation
⑤ Omohyoid
Scapula (superior border) – inferior
belly
⑥ Sternohyoid
Manubrium and sternoclavicular
joint (posterior surface)
Hyoid bone (body) – superior
belly
Ansa cervicalis (C1–C3) of
cervical plexus
⑦ Sternothyroid
Manubrium (posterior surface)
Thyroid cartilage (oblique line)
Ansa cervicalis (C1–C3) of
cervical plexus
⑧ Thyrohyoid
Thyroid cartilage (oblique line)
Hyoid bone (body)
Anterior ramus of C1 via
hypoglossal n. (CN XII)
* The omohyoid also tenses the cervical fascia (via its intermediate tendon).
516
J
Action
Depresses (fixes) hyoid, draws larynx
and hyoid down for phonation and
terminal phases of swallowing*
Depresses and fixes hyoid, raises the
larynx during swallowing
Fig. 37.5 Suprahyoid and infrahyoid
muscles
37 Neck
Stylohyoid
Digastric,
posterior belly
Digastric,
anterior belly
Thyrohyoid
Mylohyoid
Sternohyoid
Sternothyroid
Omohyoid,
superior and
inferior bellies
Intermediate tendon
of omohyoid
Coronoid
process
Geniohyoid
Mylohyoid
line
A
Left lateral view.
Head of
mandible
Mylohyoid
Mylohyoid raphe
Hyoid bone
Thyrohyoid
Thyroid cartilage
Sternothyroid
Anterior
belly
Mandibular
ramus
Digastric
Posterior
belly
Stylohyoid
Mylohyoid
Hyoid bone
(body)
B
Mylohyoid and geniohyoid (oral floor),
posterosuperior view.
Sternohyoid
Omohyoid,
superior and
inferior bellies
C
Anterior view. The sternohyoid has been
cut (right).
517
Muscle Facts (III)
Head & Neck
Fig. 37.6 Deep muscles of the neck
D
A
F
S
⑥
⑦
⑤
A
Prevertebral muscles, anterior view.
K
B
Scalene muscles, anterior view.
L
Ö
Ä
C
Suboccipital muscles, posterior view.
Deep muscles of the neck
Table 37.5
Muscle
Origin
Insertion
Innervation
Action
C3–C6 (anterior tubercles
of transverse processes)
Occipital bone (basilar part)
Anterior rami of C1–C3
Flexion of head at atlanto-occipital joints
Vertical
(intermediate)
part
C5–T3 (anterior surfaces
of vertebral bodies)
C2–C4 (anterior surfaces)
Superior
oblique part
C3–C5 (anterior tubercles
of transverse processes)
Atlas (anterior tubercle)
Anterior rami of C2–C6
Unilateral: Tilts and rotates cervical spine to
opposite side
Inferior
oblique part
T1–T3 (anterior surfaces
of vertebral bodies)
C5–C6 (anterior tubercles
of transverse processes)
C1 (lateral mass)
Occipital bone (basilar part)
Prevertebral muscles
① Longus capitis
② Longus colli
③ Rectus capitis anterior
Bilateral: Forward flexion of cervical spine
C1 (transverse process)
Occipital bone (basilar
part, lateral to occipital
condyles)
Anterior rami of C1 and
C2
⑤ Anterior scalene
C3–C6 (anterior tubercles
of transverse processes)
1st rib (scalene tubercle)
Anterior rami of C4–C6
⑥ Middle scalene
C1–C2 (transverse
processes), C3–C7
(posterior tubercles of
transverse processes)
1st rib (posterior to groove
for subclavian a.)
Anterior rami of C3–C8
C5–C7 (posterior
tubercles of transverse
processes)
2nd rib (outer surface)
Anterior rami of C6–C8
④ Rectus capitis lateralis
Unilateral: Lateral flexion of the head at the
atlanto-occipital joint
Bilateral: Flexion of the head at the atlantooccipital joint
Scalene muscles
⑦ Posterior scalene
With ribs mobile: Elevates upper ribs (during
forced inspiration)
With ribs fixed: Flexes cervical spine to same
side (unilateral), flexes neck (bilateral)
Suboccipital muscles (short nuchal and craniovertebral joint muscles)
⑧ Rectus capitis posterior minor
⑨ Rectus capitis posterior major
C1 (posterior tubercle)
C2 (spinous process)
⑩ Obliquus capitis inferior
⑪ Obliquus capitis superior
518
Occipital bone (inner third
of inferior nuchal line)
Occipital bone (middle
third of inferior nuchal line)
C1 (transverse process)
C1 (transverse process)
Occipital bone (above
insertion of rectus capitis
posterior major)
Unilateral: Rotates head to same side
Posterior ramus of C1
(suboccipital n.)
Bilateral: Extends head
Unilateral: Tilts head to same side, rotates it
to opposite side
Bilateral: Extends head
Superior
nuchal line
Inferior
nuchal line
Fig. 37.7 Deep muscles of the neck
Rectus capitis
posterior minor
37 Neck
Obliquus
capitis superior
Mastoid
process
Rectus capitis
posterior major
Posterior tubercle
of atlas (C1)
Transverse process
of atlas (C1)
Spinous process
of axis (C2)
Obliquus
capitis inferior
A
Suboccipital muscles,
posterior view.
Rectus capitis
anterior
Rectus
capitis lateralis
Atlas (C1)
Longus capitis
Superior
oblique part
Vertical part
Longus colli
Inferior
oblique part
Middle
scalene
Anterior
scalene
Middle
scalene
Posterior
scalene
Posterior
scalene
Interscalene
space
Anterior
scalene
(cut)
Groove for
subclavian a.
2nd rib
Prevertebral and scalene
B
muscles, anterior view.
Removed: Longus capitis
and anterior scalene (left).
Scalene
tubercle
1st rib
519
Head & Neck
Arteries & Veins of the Neck
Fig. 37.8 Arteries of the neck
Left lateral view. The structures of the neck are primarily supplied by
the external carotid artery (anterior branches) and the subclavian artery
(vertebral artery, thyrocervical trunk, and costocervical trunk).
Vertebral a.
Ascending
pharyngeal a.
External carotid a.
Internal carotid a.
Infrahyoid br.
Superior thyroid a.
Vertebral a.
Superior
laryngeal a.
Deep cervical a.
Inferior
thyroid a.
Cricothyroid br.
Ascending
cervical a.
Transverse
cervical a.
Common
carotid a.
Suprascapular a.
Internal
thoracic a.
Thyrocervical trunk
Highest
intercostal a.
Left
subclavian a.
520
Costocervical
trunk
Axillary a.
37 Neck
Fig. 37.9 Veins of the neck
Left lateral view. The principal veins of the neck are the internal, external, and anterior jugular veins.
Superior and inferior
ophthalmic vv.
Superior
sagittal sinus
Angular v.
Cavernous
sinus
Transverse sinus
Superficial
temporal v.
Pterygoid
plexus
Occipital v.
Posterior
auricular v.
Maxillary v.
Lingual v.
Retromandibular v.
Facial v.
Deep
cervical v.
Superior
thyroid v.
External
jugular v.
Anterior
jugular v.
Vertebral v.
Internal
jugular v.
Jugular
venous arch
Left brachiocephalic v.
Subclavian v.
Clinical box 37.1
Impeded blood flow and veins of the neck
When clinical factors (e.g., chronic lung
disease, mediastinal tumors, or infections)
impede the flow of blood to the right heart,
blood dams up in the superior vena cava
and, consequently, the jugular veins (A). This
causes conspicuous swelling in the jugular
(and sometimes more minor) veins (B).
External
jugular v.
Internal
jugular v.
External
jugular v.
External
jugular v.
Jugular
Internal
venous arch
External
jugular v.
Sternocleidomastoid
Sternocleidomastoid
jugular v.
Jugular
Left brachiovenous
arch
Subclavian v.
Subclavian v.
A
Superior vena cava
Superior vena cava
cephalic v.
Left brachiocephalic v.
Trapezius
B
Trapezius
521
Head & Neck
Lymphatics of the Neck
Fig. 37.10 Lymphatic drainage regions
Right lateral view.
Parotidauricular
Occipital
Buccal
Facial
Nuchal
Jugulofacial
venous junction
Submentalsubmandibular
Parallel to
internal
jugular vein
Laryngotracheothyroidal
Along the
accessory
nerve
Jugulosubclavian
venous
junction
Axillary
Fig. 37.11 Lymphatic drainage of the tongue and oral floor
Lymph flows into the submental and submandibular lymph nodes of
the tongue and oral floor, which ultimately drain into the jugular lymph
nodes along the internal jugular vein. Because the lymph nodes receive
drainage from both the ipsilateral and contralateral sides (B), tumor
cells may become widely disseminated in this region (e.g., metastatic
squamous cell carcinoma, especially on the lateral border of the
tongue, frequently metastasizes to the opposite side).
Superior deep
cervical l.n.
Lingual v.
Submental
l.n.
Superior deep
cervical l.n.
Jugulofacial
venous junction
Submandibular
l.n.
Inferior deep
cervical l.n.
Internal
jugular v.
Inferior deep
cervical l.n.
A Lateral view.
522
B
Coronal section showing that lymphatic drainage from one side of the tongue can drain to
either side of the neck.
Fig. 37.12 Superficial cervical lymph nodes
Right lateral view.
Retroauricular
l.n.
Superficial parotid
l.n.
37 Neck
Occipital
l.n.
Mastoid l.n.
Facial v.
Deep parotid
l.n.
Superficial cervical
lymph nodes
Table 37.6
Lymph nodes (l.n.)
Anterior superficial
cervical l.n.
Drainage region
Retroauricular l.n.
Occipital l.n.
External jugular v.
Occiput
Mastoid l.n.
Lateral superficial
cervical l.n.
Superficial parotid l.n.
Deep parotid l.n.
Anterior superficial
cervical l.n.
Lateral superficial
cervical l.n.
Parotid-auricular
region
Sternocleidomastoid
region
Fig. 37.13 Deep cervical lymph nodes
Right lateral view.
Submandibular l.n.
II
I
Submental l.n.
V
III
Level
VI
Internal jugular v.
IV
Table 37.7
I
Deep cervical lymph nodes
Lymph nodes (l.n.)
Submental l.n.
Face
Submandibular l.n.
Upper lateral
group
II
III
Drainage region
Lateral jugular
l.n. group
Middle lateral
group
Nuchal region, laryngotracheo-thyroidal region
Lower lateral
group
IV
V
L.n. in posterior cervical triangle
Nuchal region
VI
Anterior cervical l.n.
Laryngo-tracheo-thyroidal
region
523
Head & Neck
Innervation of the Neck
Branches of the spinal nerves in the neck
Table 37.8
Posterior (dorsal) ramus
Nerve
Sensory function
C1
Suboccipital n.
No C1 dermatome
Motor function
C2
Greater occipital n.
Innervate C2 dermatome
C3
3rd occipital n.
Innervate C3 dermatome
Hypoglossal n.
(CN XII)
Innervate intrinsic
nuchal muscles
C1
Lesser occipital n.
C2
Anterior (ventral) ramus
C1
C2
C2–
C3
C3–
C4
Great auricular n.
Sensory
branches
Sensory
function
—
—
Motor
branches
Motor
function
Ansa
cervicalis
Lesser occipital n.
Great auricular n.
Transverse
cervical n.
Supraclavicular nn.
Form sensory
part of cervical
plexus,
innervate
anterior and
lateral neck
Form ansa
cervicalis
(motor part
of cervical
plexus)
C3
Superior
root
Innervate
infrahyoid
muscles (except
thyrohyoid)
C4
Inferior
root
C5
Transverse
cervical n.
Supraclavicular nn.
To brachial
plexus
Phrenic n.
Contribute
to phrenic
n.*
Innervate
diaphragm and
pericardium*
Branching of the cervical plexus.
* The anterior roots of C3–C5 combine to form the phrenic nerve (see p. 66).
Fig. 37.14 Sensory innervation of the
­nuchal region
Posterior view.
Ophthalmic n. (CN V1)
C2
Lesser
occipital n.
C3
Suboccipital n. (in
suboccipital triangle)
C4
Great
auricular n.
A
Dermatomes.
Greater occipital n.
Ophthalmic n. (CN V1)
3rd occipital n.
Greater
occipital n.
Supraclavicular nn.
Lesser
occipital n.
Posterior
rami of
spinal nn.
B
Cutaneous nerve territories.
524
Great
auricular n.
Supraclavicular nn.
C5 spinal n.,
posterior ramus
C
Spinal nerve branches.
Fig. 37.15 Sensory innervation of the anterolateral neck
Left lateral view.
Greater
occipital n.+
Lesser
occipital n.
Lesser
occipital n.*
Maxillary n. (CN V2)
Great
auricular n.
Great
auricular n.*
Mandibular n. (CN V3)
Transverse
cervical n.
Posterior rami
of spinal nn.+
Transverse
cervical n.*
37 Neck
Ophthalmic n. (CN V1)
Supraclavicular
nn.
Supraclavicular nn.*
A
Cutaneous nerve territories. Trigeminal
nerve, CN V3 (orange), posterior rami (+),
anterior rami (*).
B
Sensory branches of the cervical plexus.
Fig. 37.16 Motor innervation of the anterolateral neck
Left lateral view.
Hypoglossal n. (CN XII)
C1, anterior ramus
C1
C2
Superior root of ansa cervicalis
Geniohyoid*
Thyrohyoid*
Infrahyoid
muscles
Omohyoid
C4
Inferior root of ansa cervicalis
Phrenic n.
Ansa cervicalis
Sternohyoid
Sternothyroid
Anterior
scalene
Middle
scalene
* Innervated by the anterior ramus of C1 (distributed by the hypoglossal n.).
525
Head & Neck
Larynx: Cartilage & Structure
Fig. 37.17 Laryngeal cartilages
Fig. 37.18 Epiglottic cartilage
Left lateral view. The larynx consists of five laryngeal cartilages: epiglottic, thyroid, cricoid, and the paired arytenoid and corniculate cartilages.
They are connected to each other, the trachea, and the hyoid bone by
elastic ligaments.
Lesser horn
Epiglottis
The elastic epiglottic cartilage comprises the internal skeleton of the
epiglottis, providing resilience to return it to its initial position after
swallowing.
Epiglottic
cartilage
Greater horn
Hyoid bone
(body)
Stalk of
epiglottis
A
Lingual (anterior) view.
Thyroid
cartilage
B
Left lateral
view.
C
Laryngeal (posterior)
view.
Fig. 37.19 Thyroid cartilage
Left oblique view.
Right lamina
Cricoid cartilage
Superior
horn
Superior
thyroid notch
Trachea
Superior
tubercle
Laryngeal
prominence
Left lamina
Oblique line
Inferior
thyroid notch
Inferior
tubercle
Fig. 37.20 Cricoid cartilage
Articular facet
for arytenoid
cartilage
Articular facet
for thyroid
cartilage
A
Anterior view. Arch
Articular facet
for arytenoid
cartilage
Arch
Fig. 37.21 Arytenoid and
corniculate cartilages
C
Posterior view.
Apex
Corniculate
cartilage
Colliculus
Right cartilages.
Posterior
surface
Anterolateral
surface
Arytenoid
cartilage
Vocal
process
Vocal
process
Muscular
process
A
Right lateral view.
526
Lamina
Articular facet
for thyroid
cartilage
B
Left lateral view.
Corniculate
cartilage
Inferior horn
Articular
facet
Muscular
process
Medial
surface
B
Medial view.
C
Posterior view.
37 Neck
Fig. 37.22 Structure of the larynx
The larynx is suspended from the hyoid bone, primarily by the thyrohyoid membrane. The hyoid bone provides the sites for attachment of
the suprahyoid and infrahyoid muscles.
Epiglottis
Thyrohyoid membrane
Hyoid bone
Median
thyrohyoid
lig.
Laryngeal
prominence
Thyrohyoid lig.
Cricotracheal
lig.
Vestibular
lig.
Corniculate
cartilage
Superior horn
Thyroid
cartilage
Cricothyroid
lig.
Vocal
lig.
Foramen for superior
laryngeal a. and v. and
internal laryngeal n.
Arytenoid
cartilage
Vocal process
Thyroid
cartilage
Cricoarytenoid
joint
Cricothyroid joint
Cricoid cartilage
Median
cricothyroid
lig.
Cricoid
cartilage
Cricotracheal
lig.
A
Left anterior oblique view.
B
Sagittal section, viewed from the left medial aspect. The arytenoid
cartilage alters the position of the vocal folds during phonation.
Lesser horn
Greater horn
Thyrohyoid
membrane
Superior horn
Thyroepiglottic
lig.
Inferior horn
Epiglottic
cartilage
Foramen for
superior laryngeal
a. and v. and internal
laryngeal n.
Corniculate
cartilage
Cricoarytenoid
lig.
Median
cricothyroid
lig.
Thyroid
cartilage
Vocal lig.
Conus
elasticus
Arch of
cricoid
cartilage
Vocal
process
Muscular
process
Colliculus
Cricothyroid
joint
C
Posterior view. Arrows indicate the directions of movement in the
various joints.
Corniculate
cartilage
Lamina of
cricoid cartilage
Cricoarytenoid
lig.
DSuperior view.
527
Head & Neck
Larynx: Muscles & Levels
Fig. 37.23 Laryngeal muscles
The laryngeal muscles move the laryngeal cartilages relative to one another, affecting the tension and/or position of the vocal folds. Muscles
that move the larynx as a whole (infra- and suprahyoid muscles) are
described on p. 516.
Thyroarytenoid muscle,
thyroepiglottic part
Aryepiglottic
fold
Cuneiform
tubercle
Thyroarytenoid
Cricothyroid
Corniculate
tubercle
Lateral
cricoarytenoid
Straight
part
Posterior
cricoarytenoid
Oblique
part
A
Intrinsic laryngeal muscles, left lateral oblique view.
B
Intrinsic laryngeal muscles, left lateral view. Removed: Thyroid
cartilage (left half). Revealed: Epiglottis and thyroarytenoid muscle.
Epiglottis
Arytenoid
cartilage,
vocal process
Aryepiglottic
fold
Cuneiform
tubercle
Oblique
arytenoid
Vocalis
Arytenoid
cartilage,
muscular process
Conus elasticus
Lateral cricoarytenoid
Posterior
cricoarytenoid
Middle cricoarytenoid lig.
Oblique
arytenoid
Posterior
cricoarytenoid
Articular facet
for thyroid cartilage
C
Left lateral view with the epiglottis removed.
DPosterior view.
Table 37.9
A
S
B
Open rima glottidis.
D
Actions of the laryngeal muscles
G
A
Laryngeal muscles, superior view.
H
C
Closed rima glottidis.
Effect on
rima glottidis
Muscle
Action
① Cricothyroid m.*
Tightens the vocal
folds
None
Adducts the vocal folds
Closes
⑤ Posterior
cricoarytenoid m.
Abducts the vocal folds
Opens
⑥ Lateral cricoarytenoid m.
Adducts the vocal folds
Closes
② Vocalis m.
③ Thyroarytenoid m.
④ Transverse arytenoid m.
F
528
Thyroarytenoid
Transverse
arytenoid
* The cricothyroid is innervated by the external laryngeal n. All other intrinsic
laryngeal mm. are innervated by the recurrent laryngeal n.
Levels of the larynx
Table 37.10
Level
Space
Extent
I
Supraglottic space
(laryngeal vestibule)
Laryngeal inlet (aditus
laryngis) to vestibular
folds
II
Transglottic space
(intermediate
laryngeal cavity)
Vestibular folds across
laryngeal ventricle (lateral
evagination of mucosa) to
vocal folds
III
Subglottic space
(infraglottic cavity)
Vocal folds to inferior
border of cricoid cartilage
II
III
Posterior view.
37 Neck
I
Fig. 37.24 Cavity of the larynx
Lingual
tonsil
Epiglottis
Vestibular
fold
Ventricle
Epiglottis
Hyoid bone
Piriform
recess
Hyoepiglottic
lig.
Vocal fold
Thyrohyoid
lig.
Cricoid
cartilage
Vestibular
fold
Thyroid cartilage
Aryepiglottic
fold
Cuneiform
tubercle
Corniculate
tubercle
Vocal fold
Cricoid
cartilage
Median
cricothyroid
lig.
A
Posterior view with the larynx splayed open.
Cricoid
cartilage
Esophagus
Tracheal
cartilage
Membranous
wall of trachea
B
Midsagittal section viewed from the left side.
Fig. 37.25 Vestibular and vocal folds
Coronal section, superior view.
Quadrangular
membrane
Epiglottic
cartilage
Thyroid
cartilage
Glands
Rima vestibuli
Laryngeal
saccule
Laryngeal
ventricle
Vestibular
lig.
Rima glottidis
Vocal lig.
Conus
elasticus
Vocalis
Thyroarytenoid
529
Head & Neck
Neurovasculature of the Larynx, Thyroid & Parathyroids
Fig. 37.26 Thyroid and parathyroid glands
Thyroid cartilage
Pyramidal lobe,
thyroid gland
Median
cricothyroid
lig.
Cricothyroid
Right lobe,
thyroid gland
Superior
thyroid a.
Left lobe,
thyroid gland
Isthmus
of thyroid
gland
Parathyroid glands,
superior pair
Trachea
Parathyroid glands,
inferior pair
A
Thyroid gland, anterior view.
Inferior thyroid a.
B
Thyroid and parathyroid glands, posterior view.
Parathyroid
glands
Trachea
Pretracheal visceral
layer
Pretracheal muscular
layer
Platysma
Thyroid gland
Investing
(superficial) layer
Sternocleidomastoid
Internal
jugular v.
Carotid
sheath
Common
carotid a.
Vagus n.
Esophagus
Investing (superficial) layer
Prevertebral
layer
Buccopharyngeal
fascia (continuous with
pretracheal layer)
Retropharyngeal
space
Muscular pretracheal layer
Visceral pretracheal layer
Carotid sheath
Prevertebral layer
530
C T
ransverse section of neck at level of C6, superior view. Topographical relations
of the thyroid and parathyroid glands. See p. 533 for coverage of the layers of
the deep cervical fascia, which are shown here.
Fig. 37.27 Arteries and nerves of the larynx
Anterior view. Removed: Thyroid gland (right half).
Left vagus n. (CN X)
Superior
thyroid a.
Superior laryngeal n.
Superior
laryngeal a.
Internal laryngeal n.
Common
carotid a.
External laryngeal n.
Fig. 37.28 Veins of the larynx
37 Neck
Right vagus n.
(CN X)
Left lateral view. Note: The inferior thyroid vein
generally drains into the left brachiocephalic
vein.
Cricothyroid br.
Inferior laryngeal a.
Recurrent
laryngeal nn.
Inferior
thyroid a.
Thyrocervical
trunk
Left
subclavian a.
Right recurrent
laryngeal n.
Left
recurrent
laryngeal n.
Aortic arch
Facial v.
Superior
thyroid v.
Superior
laryngeal v.
Middle
thyroid vv.
Inferior
laryngeal v.
Thyroid
venous
plexus
Internal
jugular v.
Inferior
thyroid v.
Left brachiocephalic v.
Subclavian v.
Fig. 37.29 Neurovasculature of the larynx
Left lateral view.
Epiglottis
Superior
laryngeal n.
Internal
laryngeal n.
Hyoid bone
Superior
laryngeal a. and v.
Thyrohyoid
membrane
Thyrohyoid
Inferior pharyngeal
constrictor
External
laryngeal n.
Median
cricothyroid lig.
Cricothyroid
Middle thyroid v.
Inferior thyroid a.
Thyroid gland
Esophagus
A
Superficial layer.
Left recurrent
laryngeal n.
Hyoid bone
Median
thyrohyoid
lig.
Thyroarytenoid
Lateral
cricoarytenoid
Median cricothyroid lig.
Cricothyroid
Tracheal brs.
Internal
laryngeal n.
Superior
laryngeal
a. and v.
Galen’s
anastomosis
Posterior
cricoarytenoid
Esophagus
Middle
thyroid v.
Inferior
thyroid a.
Left recurrent
laryngeal n.
B
Deep layer. Removed: Cricothyroid muscle and left lamina of thyroid
cartilage. Retracted: Pharyngeal mucosa.
531
Head & Neck
Topography of the Neck: Regions & Fascia
Table 37.11
Region
① Anterior
cervical
region
(triangle)
②
①
③
Regions of the neck
Divisions
Contents
Submandibular
(digastric) triangle
Submandibular gland and l.n., hypoglossal
n. (CN XII), facial a. and v.
Submental triangle
Submental l.n.
Muscular triangle
Sternothyroid and sternohyoid mm.,
thyroid and parathyroid glands
Carotid triangle
Carotid bifurcation, carotid body,
hypoglossal (CN XII) and vagus (CN X) nn.
② Sternocleidomastoid region*
F
③ Lateral
cervical
region
(posterior
triangle)
A
Right anterior oblique view.
B
Left posterior oblique view.
Sternocleidomastoid, common carotid
a., internal jugular v., vagus n. (CN X),
jugular l.n.
Omoclavicular
(subclavian) triangle
Subclavian a., subscapular a.,
supraclavicular l.n.
Occipital triangle
Accessory n. (CN XI), trunks of brachial
plexus, transverse cervical a., cervical
plexus (posterior branches)
Nuchal mm., vertebral a., cervical
plexus
④ Posterior cervical region
* The sternocleidomastoid region also contains the lesser supraclavicular fossa.
Omohyoid,
superior belly
Fig. 37.30 Cervical regions
Submandibular
triangle
Submandibular
(digastric) triangle
Digastric, anterior
and posterior bellies
Digastric,
posterior belly
Digastric,
anterior belly
Sternocleidomastoid
Submental
triangle
Occipital
triangle
Carotid
triangle
Submental
triangle
Trapezius
Omohyoid,
inferior belly
Sternohyoid
Hyoid bone
Omoclavicular
(subclavian)
triangle
Sternocleidomastoid
Carotid
triangle
Omohyoid,
superior belly
Occipital
triangle
Lesser supraclavicular fossa
Trapezius
Omoclavicular
(subclavian)
triangle
A
Anterior view.
532
Lesser supraclavicular fossa
Muscular triangle
Omohyoid,
inferior belly
B
Left lateral view.
Clavicle
Table 37.12
Deep cervical fascia
The deep cervical fascia is divided into four layers that enclose the structures of the neck.
① Investing (superficial) layer
Pretracheal layer
Type of fascia
Description
Muscular
Envelopes entire neck; splits to enclose sternocleidomastoid and trapezius muscles
② Muscular
Encloses infrahyoid muscles
③ Visceral
Surrounds thyroid gland, larynx, trachea, pharynx, and esophagus
④ Prevertebral layer
Muscular
Surrounds cervical vertebral column and associated muscles
⑤ Carotid sheath
Neurovascular
Encloses common carotid artery, internal jugular vein, and vagus nerve
37 Neck
Layer
① Superficial
③ Visceral
layer of deep
pretracheal fascia
cervical fascia
② Muscular
pretracheal fascia
Retropharyngeal
space
①
Nuchal
lig.
Carotid
sheath ⑤
Prevertebral
fascia ④
Prevertebral layer
(deep nuchal
fascia)
Buccopharyngeal
fascia
①
Spinal cord
②
④
③
Superficial layer of deep cervical
(superficial nuchal) fascia
A
Transverse section at level of C5 vertebra.
B
Midsagittal section, left lateral view.
Fig. 37.31 Deep cervical fascial layers
Anterior view.
Mandible
Parotid gland
① Investing
(superficial) layer
Sternohyoid
③ Pretracheal
visceral layer
② Pretracheal
muscular layer
Sternocleidomastoid
Carotid sheath
⑤
Omohyoid
Prevertebral
layer
④
Trapezius
Clavicle
533
Head & Neck
Topography of the Anterior Cervical Region
Fig. 37.32 Anterior cervical
triangle
Anterior view.
Mandible
Facial n. (CN VII),
cervical br.
Parotid gland
Investing
layer of deep
cervical fascia
Platysma
External
jugular v.
Anterior
jugular v.
Great auricular n.
Pretracheal
layer of deep
cervical fascia
Transverse
cervical n.
A
Superficial layer. Removed:
Subcutaneous platysma
(right side) and investing
layer of deep cervical fascia
(center).
Supraclavicular nn.
Superior
laryngeal a.
Internal jugular v.
External
laryngeal n.
Right common
carotid a.
Superior
thyroid a.
External
jugular v.
Sternocleidomastoid,
sternal head
Internal
laryngeal n.
Jugular
venous arch
Thyroid
cartilage
Hypoglossal n.
(CN XII)
Thyrohyoid br.
(C1 via CN XII)
Median thyrohyoid
lig.
Thyrohyoid
Omohyoid,
superior belly (cut)
Sternocleidomastoid
Cricothyroid
Sternothyroid
B
Deep layer. Removed:
Pretracheal lamina (middle
layer of cervical fascia).
Cuts: Sternohyoid, sternothyroid, and thyrohyoid
(right side); sternohyoid
(left side).
534
Sternohyoid (cut)
Superior
laryngeal a.
Internal
laryngeal n.
Superior
thyroid a.
37 Neck
Internal jugular v.
Thyroid cartilage
Vagus n. (CN X)
Accessory n. (CN XI)
Trapezius
Phrenic n.
External
laryngeal n.
Brachial plexus
Cricothyroid
Ascending cervical a.
Internal jugular v.
Inferior thyroid a.
Suprascapular n.
Thyrocervical
trunk
Transverse cervical a.
Suprascapular a.
Vagus n. (CN X)
Subclavian v.
Subclavian a.
Thyrocervical trunk
C
Deep anterior
cervical region.
Inferior thyroid v.
Median
thyrohyoid lig.
Inferior laryngeal n.
Thyroid
cartilage
Common
carotid a.
Left common carotid a.
Internal
jugular v.
Vagus n. (CN X)
External
laryngeal n.
Accessory n. (CN XI)
Trapezius
Middle
cervical
ganglion
Phrenic n.
Cricothyroid
Anterior
scalene
Sympathetic
trunk
Brachial
plexus
Inferior
thyroid a.
Ascending
cervical a.
C8, anterior root
Transverse
cervical a.
Vertebral a.
Suprascapular a.
T1, anterior root
External
jugular v.
Left recurrent
laryngeal n.
Subclavian
a. and v.
Stellate
ganglion
DRoot of the neck.
Left common carotid a.
Thoracic duct
Internal thoracic a.
Thyrocervical trunk
535
Head & Neck
Topography of the Anterior & Lateral Cervical Regions
Fig. 37.33 Deep anterior cervical region
The deep midline viscera of the anterior cervical region are the larynx
and thyroid gland. The two lateral neurovascular pathways primarily
supply these organs.
Mandible
Parotid gland
Parotid gland
Mylohyoid
Digastric,
anterior belly
Hyoid
Sternocleidomastoid
Thyrohyid membrane
(median thyrohyoid lig.)
Thyroid cartilage
Internal jugular v.
Cricothyroid
Pyramidal lobe
Phrenic n.
Thyroid gland
Right common
carotid a.
Thyrocervical
trunk
Subclavian a.
Brachiocephalic
trunk
536
Sternohyoid
Thyrohyoid
Superior thyroid a.
Superior thyroid v.
Middle scalene
Trapezius
Accessory n.
Anterior
scalene
Brachial plexus
Vagus n.
Phrenic n.
Transverse
cervical a.
Middle
thyroid v.
Inferior
thyroid vv.
Left recurrent
laryngeal n.
Clavicle
Left common
carotid a.
Fig. 37.34 Carotid triangle
Digastric,
posterior belly
Right lateral view. Internal jugular and
facial veins removed.
Internal
carotid a.
External
carotid a.
Facial a.
Hypoglossal n.
(CN XII)
Facial n. (CN VII) marginal
mandibular br.
Superior
cervical ganglion
37 Neck
Lingual a.
Internal jugular
v. (cut)
Submandibular gland
Occipital a.
Superior laryngeal n.
Vagus n.
Superior root
of ansa cervicalis
(descendens hypoglossus)
Hyoid bone
Thyrohyoid br. (C1 via CN XII)
Carotid body
Superior thyroid a.
Common carotid a.
Thyrohyoid
Sternocleidomastoid
Investing layer of
deep cerical fascia
Sternothyroid
Omohyoid, superior belly
Ansa cervicalis
Fig. 37.35 Deep lateral cervical region
Right lateral view with sternocleidomastoid windowed.
Internal carotid a.
External carotid a.
Facial a. and v.
Hypoglossal n.
(CN XII)
Superior cervical
ganglion
Sympathetic
trunk
Accessory n. (CN XI)
Middle scalene
Anterior scalene
Internal jugular v.
Superficial
cervical a.
Carotid body
Carotid bifurcation
Superior thyroid a.
Thyroid gland
Common carotid a.
Ansa cervicalis
Sternohyoid
Phrenic n.
Inferior thyroid a.
Brachial plexus
Omohyoid,
inferior belly
Vagus n. (CN X)
Sternothyroid
Sternocleidomastoid
537
Head & Neck
Topography of the Lateral Cervical Region
Fig. 37.36 Lateral cervical region
Parotid gland
Right lateral view. The contents of the deep
lateral cervical region are found in Fig. 37.34.
Facial n. (CN VII),
cervical br.
Masseter
Lesser occipital n.
Great auricular n.
Erb’s point
External
jugular v.
Lateral supraclavicular nn.
Sternocleidomastoid, posterior
border
Trapezius,
anterior border
Transverse cervical
and CN VII anastomosis
Superficial (investing) layer
of deep cervical fascia
Transverse cervical n.
Clavicle
A
Subcutaneous layer.
Intermediate supraclavicular nn.
Medial supraclavicular nn.
Lesser occipital n.
Great auricular n.
Accessory n. (CN XI)
External
jugular v.
Erb’s point
Superficial (investing) layer
of deep cervical fascia
Superficial
cervical l.n.
Superficial
cervical a.
Sternocleidomastoid
Trapezius
Transverse
cervical n.
Supraclavicular nn.
Prevertebral layer of
deep cervical fascia
Superficial
cervical v.
538
Pretracheal layer of
deep cervical fascia
B
Subfascial layer. Removed: Superficial
(investing) layer of deep cervical fascia.
Parotid gland
37 Neck
Lesser occipital n.
Great auricular n.
Accessory n. (CN XI)
Lateral supraclavicular n.
Intermediate
supraclavicular n.
External
jugular v.
Sternocleidomastoid
Trapezius
Superficial
cervical a. and v.
Prevertebral layer of
deep cervical fascia
Transverse
cervical n.
Right subclavian v.
Omohyoid,
inferior belly
C
Deep layer. Removed: Pretracheal layer of
deep cervical fascia. Revealed: Omohyoid,
omoclavicular (subclavian) triangle.
Splenius capitis
Accessory n. (CN XI)
Levator scapulae
Middle scalene
Trapezius
Posterior
scalene
Superficial
cervical a.
DDeepest layer. Removed: Prevertebral
layer of deep cervical fascia. Revealed:
Muscular floor of posterior triangle,
brachial plexus, and phrenic nerve.
Omohyoid,
inferior belly
Phrenic n.
Sternocleidomastoid
Brachial plexus
Anterior
scalene
Suprascapular a.
Right subclavian v.
539
Head & Neck
Topography of the Posterior Cervical Region
Fig. 37.37 Occipital and posterior cervical regions
Posterior view. Subcutaneous layer (left), subfascial layer (right). The
occiput is technically a region of the head, but it is included here due
to the continuity of the vessels and nerves from the neck. Removed on
right side: Investing layer of deep cervical fascia.
Occipital
a. and v.
Greater
occipital n.
Occipital l.n .
Semispinalis
capitis
3rd occipital n.
Lesser occipital n.
Lesser occipital n.
Sternocleidomastoid
Splenius capitis
Great auricular n.
Accessory n. (CN XI)
Posterior cutaneous
br. (cervical nn.,
posterior rami)
540
Trapezius
37 Neck
Fig. 37.38 Suboccipital triangle
Right side, posterior view, windowed. The suboccipital triangle is
bounded by the suboccipital muscles (rectus capitis posterior major
and obliquus capitis superior and inferior) and contains the vertebral
artery. The left and right vertebral arteries pass through the atlantooccipital membrane and combine to form the basilar artery.
Occipital a.
Splenius
capitis
Sternocleidomastoid
Semispinalis
capitis
Obliquus capitis
superior
Rectus capitis
posterior minor
Greater
occipital n.
Suboccipital n.
Vertebral a.
Rectus capitis
posterior major
Obliquus
capitis inferior
Spinous process
of axis (C2)
Occipital a.
Great auricular n.
Transverse process
of atlas (C1)
Cervical posterior
intertransversarius
3rd occipital n.
Longissimus capitis
Spinous process
of C3
Semispinalis capitis
Splenius capitis
541
38
Bones of the Head
Head & Neck
Anterior & Lateral Skull
Fig. 38.1 Lateral skull
Left lateral view.
Frontal bone
Coronal suture
Pterion
Squamous suture
Parietal bone
Sphenoparietal
suture
Sphenofrontal
suture
Sphenosquamous
suture
Supraorbital
foramen
Glabella
Sphenoid bone,
greater wing
Ethmoid bone
Lacrimal bone
Zygomatic
bone,
temporal
process
Nasal bone
Zygomatic bone,
frontal process
Temporal
bone,
zygomatic
process
Infraorbital
foramen
Anterior
nasal spine
Maxilla,
zygomatic
process
Lambdoid
suture
Mastoid Asterion
foramen
Tympanomastoid
fissure
External acoustic
meatus
Postglenoid
tubercle
Styloid
process
Articular
tubercle
(articular
eminence)
Mandible,
body
Oblique
line
Mental
protuberance
Mastoid
process
Zygomatic
Mandible, arch
ramus
Zygomatic
bone
Mental foramen
Table 38.1
Bones of the skull
The skull is subdivided into the neurocranium (gray) and viscerocranium (orange). The neurocranium protects the brain, while
the viscerocranium houses and protects the facial regions.
Neurocranium
Viscerocranium
• Ethmoid bone (cribriform plate)*
• Frontal bone
• Occipital bone
• Parietal bone
• Sphenoid bone
• Temporal bone (petrous and squamous parts)
• Mandible
• Ethmoid bone
• Maxilla
• Hyoid bone
• Nasal bone
• Inferior nasal concha
• Palatine bone
• Lacrimal bone
• Sphenoid bone (pterygoid process)
• Temporal bone
• Vomer
*Most of the ethmoid bone is in the viscerocranium; most of the sphenoid bone is in the neurocranium. The temporal bone is
divided between the two.
542
Fig. 38.2 Anterior skull
Anterior view.
Nasion
Superciliary arch
Frontal bone
Maxilla,
frontal process
Parietal bone
Frontal incisure
(notch)
Supraorbital
foramen
Supraorbital
margin
Nasal bone
Sphenoid bone,
greater wing
Sphenoid bone,
lesser wing
Temporal bone
38 Bones of the Head
Glabella
Orbit
Ethmoid bone,
perpendicular
plate
Sphenoid bone,
greater wing
Infraorbital
margin
Ethmoid bone,
middle nasal
concha
Zygomatic bone,
frontal process
Piriform (anterior
nasal) aperture
Maxilla,
zygomatic process
Vomer
Infraorbital foramen
Inferior nasal
concha
Anterior nasal
spine
Mandible,
ramus
Intermaxillary
suture
Oblique line
Maxilla,
alveolar process
Mandible,
body
Mental foramen
Mental protuberance
Mental tubercles
Clinical box 38.1
Fractures of the face
The framelike construction of the facial skeleton leads to characteristic patterns for fracture lines
(classified as Le Fort I, II, and III fractures).
A
Le Fort I.
B
Le Fort II.
C
Le Fort III.
543
Head & Neck
Posterior Skull & Calvaria
Fig. 38.3 Posterior skull
Posterior view.
Parietal foramina
Lambda
Sagittal
suture
Parietal bone
Parietal
eminence
Lambdoid
suture
Occipital
bone
Temporal bone,
squamous part
Supreme
nuchal line
Temporal bone,
petrous part
Asterion
Superior
nuchal line
External occipital
protuberance (inion)
Median nuchal line
(external occipital crest)
Mastoid foramina
Mastoid notch
Temporal bone,
mastoid process
Temporal bone,
styloid process
Inferior
nuchal line
Vomer
Occipital condyle
Sphenoid bone,
pterygoid process
Palatine bone
Mandible,
ramus
Mandibular foramen
Maxilla,
palatine process
Mylohyoid groove
Incisive foramen
Mandible,
body
Submandibular fossa
Mylohyoid line
Digastric fossa
Genial (mental) spines
Clinical box 38.2
Cranial Fontanelles
In the neonate, there are areas between still-growing
cranial bones not occupied by bone: the fontanelles.
While these regions close at different times, they
have clinical implications. The posterior fontanelle
provides a reference point for describing the position
of the fetal head during childbirth, and the anterior
fontanelle provides a potential access site for drawing
cerebrospinal fluid in infants (e.g., in suspected
meningitis).
544
Coronal
suture
Anterior
fontanelle
Sphenoidal
fontanelle
Frontal
suture
Squamous
suture
A
Posterior
fontanelle
Lamdoid
suture
Sphenosquamosal Mastoid
suture
fontanelle
Anterior
fontanelle
Sagittal
suture
Posterior
fontanelle
B
Coronal
suture
Fig. 38.4 Calvaria
Fig. 38.5 Structure of the calvaria
Cross section.
Emissary v.
Scalp
Outer
table
Diploë
Dural
sinus
Calvaria
Inner
table
38 Bones of the Head
Diploic vv.
Dura
mater
Frontal
bone
Coronal
suture
Parietal
bone
Sagittal
suture
Frontal
bone
Parietal
foramen
Occipital bone
Frontal
crest
Frontal
sinus
Lambdoid
suture
A
External calvaria, superior view.
Grooves for
middle
meningeal a.
Groove
for
superior
sagittal
sinus
Parietal
bone
Granular
foveolae
(for arachnoid
granulations)
Internal calvaria, inferior view. The interior
B
of the calvaria is marked by grooves for the
meningeal arteries, dural venous sinuses, and
arachnoid granulations (see pp. 590–591).
Parietal foramen
545
Head & Neck
Base of the Skull
Fig. 38.6 Base of the skull: Exterior
Inferior view. Revealed: Foramina and canals for blood vessels
(see p. 582) and cranial nerves. Note: This view allows visual
access into the posterior region of the nasal cavity.
Median palatine
suture
Transverse palatine
suture
Palatine bone
Palatine
process
Zygomatic
process
Maxilla
Choana
Zygomatic bone,
temporal surface
Greater palatine
foramen
Inferior orbital fissure
Lesser palatine
foramen
Hamulus (of medial
pterygoid plate)
Vomer
Pterygoid
process
Incisive
foramen
Medial
plate
Zygomatic
arch
Lateral
plate
Fossa of
pterygoid canal
Palatovaginal
(pharyngeal) canal
Articular tubercle
Pharyngeal
tubercle
Foramen ovale
Foramen spinosum
Mandibular fossa
Foramen lacerum
Petrotympanic
fissure
Carotid canal
Styloid process
Occipital condyle
Jugular foramen
Mastoid process
Stylomastoid
foramen
Mastoid notch
(for digastric belly)
Hypoglossal
canal
Condylar canal
Foramen
magnum
Mastoid
foramen
Inferior
nuchal line
Parietal bone
External occipital
crest
Superior
nuchal line
Supreme
nuchal line
546
External occipital
protuberance (inion)
Fig. 38.7 Cranial fossae
The interior of the skull base consists of three successive fossae that
become progressively deeper in the frontal-to-occipital direction.
Middle
cranial fossa
Anterior
cranial fossa
Jugum
sphenoidale
Lesser wing of
sphenoid bone
Posterior
cranial fossa
Dorsum
sellae
Middle
cranial fossa
Foramen
magnum
Petrous ridge
(crest),
temporal bone
Posterior
cranial fossa
38 Bones of the Head
Anterior
cranial fossa
Foramen
magnum
A
Midsagittal section, left lateral view.
Fig. 38.8 Base of the skull: Interior
Superior view.
Chiasmatic
groove
Optic canal
Anterior clinoid
process
Foramen ovale
Foramen
spinosum
Foramen
lacerum
Dorsum
sellae
Hiatus of
facial canal
Clivus
Petrooccipital
fissure
Hypoglossal
canal
Groove for
sigmoid
sinus
Groove for
transverse
sinus
B
Superior view of opened skull.
Frontal
crest
Frontal
sinus
Ethmoid bone,
cribriform plate
Ethmoid bone,
crista galli
Frontal bone
Sphenoid bone,
lesser wing
Sphenoid bone,
greater wing
Sphenoid bone,
hypophyseal fossa
Posterior clinoid
process
Groove for lesser
petrosal nerve
Temporal bone,
petrous part
Internal
acoustic meatus
Jugular foramen
Foramen magnum
Cerebellar fossa
Internal
occipital crest
Internal occipital
protuberance
Cerebral fossa
547
Head & Neck
Neurovascular Pathways Exiting or Entering the Cranial Cavity
Fig. 38.9 Summary of the neurovascular structures exiting or entering the cranial cavity
Cribriform plate
Incisive canal
Olfactory n., anterior and posterior ethmoidal aa.
Nasopalatine n., sphenopalatine a.
Greater palatine foramen
Optic canal
Greater palatine n. and a.
Optic n., ophthalmic a.
Lesser palatine foramina
Superior orbital fissure
Superior ophthalmic v.
Abducent n.
Lacrimal n.
Nasociliary n.
Lesser palatine n. and a.
Oculomotor n.
Foramen lacerum
Deep petrosal n.,
greater petrosal n.
Frontal n.
Trochlear n.
Foramen spinosum
Foramen rotundum
Middle meningeal a.,
meningeal br. of
mandibular n. (CN V3)
Maxillary n. (CN V2)
Foramen ovale
Carotid canal
Mandibular n. (CN V3),
lesser petrosal n.
accessory meningeal a.
Internal carotid a.,
internal carotid sympathetic plexus
Carotid canal
Petrotympanic
fissure
Internal carotid a.,
internal carotid sympathetic plexus
Anterior tympanic a.,
chorda tympani
Foramen spinosum
Stylomastoid
foramen
Middle meningeal a.,
meningeal br. of
mandibular n. (CN V3)
Facial n.,
stylomastoid a.
Hiatus of canal for
lesser petrosal n.
Jugular foramen
Lesser petrosal n.,
superior tympanic a.
Internal jugular v.
Glossopharyngeal n.
Vagus n.
Hiatus of canal for
greater petrosal n.
Accessory n.
Inferior petrosal
sinus
Greater petrosal n.
Posterior
meningeal a.
Internal acoustic meatus
Labyrinthine a. and v.
Mastoid foramen
Vestibulocochlear n.
Emissary v.
Facial n.
Hypoglossal canal
Jugular foramen
Sigmoid
sinus
Glossopharyngeal n.
Vagus n.
Inferior
petrosal sinus
Spinal v.
Posterior
spinal a.
Accessory n.
Posterior
meningeal a.
Anterior
spinal a.
Medulla
oblongata
Vertebral a.
A
Cranial cavity (interior of skull base),
left side, superior view.
548
Hypoglossal n., venous
plexus of hypoglossal canal
Foramen magnum
Accessory n.
Condylar canal
Condylar emissary v.
B
Exterior of skull base, left side,
inferior view
38 Bones of the Head
Fig. 38.10 Cranial nerves exiting the cranial cavity
Cranial cavity (interior of skull base), right side, superior view. Removed:
Brain and tentorium cerebelli. The ends of the cranial nerves have been
cut to reveal the fissures, fossae, or dural cave where they pass through
the cranial fossa.
Olfactory bulb
Olfactory fibers
(filia olfactoria)
(CN I)
Anterior cranial fossa
Olfactory tract
Optic n.
(CN II)
Diaphragma sella
Internal carotid a.
Infundibular stalk
Oculomotor n.
(CN III)
Lateral dural wall
of cavernous sinus
Trochlear n.
(CN IV)
Abducent n. (CN VI)
Middle cranial fossa
Trigeminal n. (CN V)
Facial and vestibulocochlear
nn. (CN VII, CN VIII)
Glossopharyngeal n.
(CN IX)
Vagus n.
(CN X)
Accessory n.
(CN XI)
Inferior
sagittal sinus
Hypoglossal n.
(CN XII)
Tentorium cerebelli
Posterior cranial fossa
Superior
sagittal sinus
Tentorium
cerebelli (cut)
549
Head & Neck
Ethmoid & Sphenoid Bones
regions: orbit (see pp. 602–603), nasal cavity (see pp. 616–617), oral
cavity (see pp. 636–637), and ear (see pp. 624–625).
The structurally complex ethmoid and sphenoid bones are shown here
in isolation. The other bones of the skull are shown in their respective
Fig. 38.11 Ethmoid bone
The ethmoid bone is the central bone of the nose and paranasal air
sinuses (see pp. 616–619).
Crista galli
Ethmoid
air cells
Orbital
plate
Middle
concha
Perpendicular
plate
Perpendicular
plate
Crista galli
A
Anterior view.
Crista galli
Superior
concha
Ethmoid
bulla
Cribriform
plate
Ethmoid
air cells
Orbital
plate
Superior view.
B
Ethmoid
infundibulum
Uncinate
process
Middle concha
Perpendicular plate
Posterior view.
C
Crista galli
Anterior
ethmoid foramen
Posterior
ethmoid
foramen
Ethmoid air cells
Orbital
plate
(lamina
papyracea)
Perpendicular
plate
Middle
concha
DLeft lateral view.
550
Lesser
wing
Sphenoid
crest
Fig. 38.12 Sphenoid bone
Aperture of
sphenoid sinus
The sphenoid bone is the most structurally
complex bone in the human body.
38 Bones of the Head
Orbital surface
Temporal
surface
Superior
orbital
fissure
Foramen
rotundum
Pterygoid
canal
Medial
plate
Lateral
plate
Pterygoid
hamulus
A
Anterior
view.
Lesser
wing
Pterygoid
process
Optic
canal
Jugum
sphenoidale
Superior orbital
fissure
Greater
wing
Chiasmatic groove
Foramen
rotundum
Anterior clinoid process
Foramen ovale
Foramen
spinosum
Hypophyseal fossa
(sella turcica)
Tuberculum
sellae
B
Superior view.
Lesser
wing
Optic
canal
Dorsum
sellae
Posterior clinoid
process
Posterior clinoid
process
Superior orbital
fissure
Anterior
clinoid
process
Greater wing,
cerebral surface
Foramen
rotundum
Pterygoid
canal
C
Posterior
view.
Pterygoid
notch
Cancellous trabeculae
Dorsum
sellae
Medial plate Pterygoid
process
Lateral plate
Lesser
wing
Sphenoid
crest
Aperture of
sphenoid sinus
Greater wing
Foramen
rotundum
Greater wing
Medial plate Pterygoid
Lateral plate process
Temporal
surface
Foramen ovale
Foramen spinosum
D
Inferior view. Note: The vomer sits
below the sphenoid crest (see
p. 636).
Pterygoid
hamulus
Superior orbital
fissure
Body
Pterygoid
fossa
551
39
Muscles of the Skull & Face
Head & Neck
Muscles of Facial Expression & of Mastication
The muscles of the skull and face are divided into two groups. The
muscles of facial expression make up the superficial muscle layer in
the face. The muscles of mastication are responsible for the movement
of the mandible during mastication (chewing).
Fig. 39.1 Muscles of facial expression
Epicranial aponeurosis
(galea aponeurotica)
Occipitofrontalis,
frontal belly (frontalis)
Corrugator
supercilii
Procerus
Orbicularis
oculi
Levator labii
superioris
alaeque nasi
Levator labii
superioris
alaeque nasi (O)
Levator labii
superioris (O)
Nasalis
Zygomaticus
minor (O)
Levator labii
superioris
Zygomaticus
major (O)
Zygomaticus
minor
Levator
anguli oris (O)
Zygomaticus
major
Buccinator
Levator
anguli oris
Risorius
Platysma
Depressor
anguli oris
Risorius (I)
Masseter (muscle
of mastication)
Orbicularis
oris
Depressor
anguli oris (O)
Depressor
labii inferioris (O)
Depressor
labii inferioris
A
Anterior view. Muscle origins (O) and insertions (I) indicated on left side of face.
552
Mentalis
Epicranial
aponeurosis
Occipitofrontalis,
frontal belly
(frontalis)
Temporoparietalis
Orbicularis
oculi
Anterior auricular
muscle
39 Muscles of the Skull & Face
Superior
auricular muscle
Nasalis
Levator labii
superioris
alaeque nasi
Levator labii
superioris
Occipitofrontalis,
occipital belly
(occipitalis)
Zygomaticus
minor
Orbicularis
oris
Posterior auricular
muscle
Zygomaticus
major
Risorius
Depressor
labii inferioris
Mentalis
B
Left lateral view.
Depressor
anguli oris
Platysma
Fig. 39.2 Muscles of mastication
Left lateral view.
Temporalis
(cut)
Temporalis
Capsule of temporomandibular joint
Styloid process,
temporal bone
Deep layer
A
Superficial layer.
Superficial layer
Masseter
B
Deep layer. Removed:
Mandible (coronoid
process) and lower
temporalis.
Lateral
pterygoid
Joint capsule
of TMJ
Lateral lig.
of TMJ
Medial
pterygoid
Masseter (cut)
553
Head & Neck
Muscle Origins & Insertions on the Skull
Fig. 39.3 Lateral skull: Origins and insertions
Left lateral view. Muscle origins are shown in red, insertions
in blue. Note: There are generally no bony insertions for the
muscles of facial expression. These muscles insert into skin
and other muscles of facial expression.
Sternocleidomastoid
and trapezius: Accessory n. (CN XI)
Mm. of facial expression:
Facial n. (CN VII)
Occipitofrontalis,
occipital belly
Sternocleidomastoid
Corrugator supercilii
Trapezius
Orbital part
Orbicularis
oculi
Lacrimal part
Levator labii
superioris alaeque nasi
Nuchal and
intrinsic back mm.:
Posterior rami
of cervical nn.
Zygomaticus major
Levator labii superioris
Zygomaticus minor
Levator anguli oris
Nasalis
Semispinalis capitis
Transverse
part
Alar part
Obliquus capitis
superior
Depressor septi nasi
Rectus capitis
posterior major
Orbicularis oris
Buccinator
Mm. of mastication:
Trigeminal n., mandibular division (CN V3)
Mentalis
Orbicularis oris
Masseter
Depressor
labii inferioris
Lateral pterygoid
Depressor
anguli oris
Temporalis
Medial pterygoid
(see Fig. 39.4)
Platysma
Fig. 39.4 Mandible: Origins and insertions
Medial view of right hemimandible (inner surface).
Muscle origins are shown in red, insertions in blue.
Temporalis
Lateral
pterygoid
Buccinator
Medial
pterygoid
Genioglossus
Suprahyoid mm.
Mylohyoid
Geniohyoid
Digastric, anterior belly
554
Rectus capitis
posterior minor
Splenius capitis
Longissimus capitis
Fig. 39.5 Skull base: Origins and insertions
Inferior view of external skull.
Muscle origins are shown in red, insertions in blue.
Masseter
Medial
pterygoid
Lateral
pterygoid
Pharyngeal mm.:
Glossopharyngeal
n. (CN IX) and
vagus n. (CN X)
Temporalis
Lingual mm.: Hypoglossal n. (CN XII)
Tensor veli palatini
39 Muscles of the Skull & Face
Mm. of mastication:
Trigeminal n., mandibular division (CN V3)
Levator veli palatini
Hyoglossus
(see Fig. 40.25)
Stylopharyngeus
Genioglossus
(see Fig. 40.25)
Middle pharyngeal
constrictor
(not shown)
Styloglossus
Stylohyoid
Digastric,
posterior belly
Prevertebral mm.:
Ventral cervical n.
rami and cervical
plexus
Nuchal and intrinsic
back mm.:
Posterior rami of
cervical nn.
Rectus capitis
lateralis
Longus capitis
Splenius capitis
Rectus capitis
anterior
Longissimus capitis
Obliquus
capitis superior
Sternocleidomastoid
and trapezius: Accessory n. (CN XI)
Rectus capitis
posterior major
Rectus capitis
posterior minor
Sternocleidomastoid
Trapezius
Semispinalis capitis
Fig. 39.6 Hyoid bone: Origins and insertions
The larynx is suspended from the hyoid bone, primarily by the
thyrohyoid membrane. The hyoid bone is the site for attachment for
Mylohyoid
the suprahyoid and infrahyoid muscles. Muscle insertions are shown
in blue.
Geniohyoid
Geniohyoid
Stylohyoid
Mylohyoid
Stylohyoid
Thyrohyoid
Omohyoid
A
Anterior view.
Sternohyoid
Sternohyoid
Omohyoid
Thyrohyoid
B
Oblique left lateral view.
555
Head & Neck
Muscle Facts (I)
The muscles of facial expression originate on bone and/or fascia and
insert into the subcutaneous tissue of the face. This allows them to
produce their effects by pulling on the skin.
Fig. 39.7 Occipitofrontalis
Fig. 39.9 Muscles
of the ear
Anterior view.
Left lateral view.
⑦
①
⑥
⑧
②
Fig. 39.8 Muscles of the palpebral fissure and nose
Anterior view.
③
⑤
④
A
Orbicularis oculi.
Table 39.1
B
Nasalis.
C
Levator labii superioris alaeque nasi.
Muscles of facial expression: Forehead, nose, and ear
Muscle
Origin
Insertion*
Main action(s)**
Epicranial aponeurosis
Skin and subcutaneous tissue of
eyebrows and forehead
Elevates eyebrows, wrinkles skin of forehead
② Procerus
Nasal bone, lateral nasal cartilage
(upper part)
Skin of lower forehead between
eyebrows
Pulls medial angle of eyebrows inferiorly,
producing transverse wrinkles over bridge
of nose
③ Orbicularis oculi
Medial orbital margin, medial palpebral
ligament, lacrimal bone
Skin around margin of orbit,
superior and inferior tarsal plates
Acts as orbital sphincter (closes eyelids)
• Palpebral portion gently closes
• Orbital portion tightly closes (as in winking)
④ Nasalis
Maxilla (superior region of canine ridge)
Nasal cartilages
Flares nostrils by drawing ala (side) of nose
toward nasal septum
⑤ Levator labii superioris alaeque nasi
Maxilla (frontal process)
Alar cartilage of nose and upper lip
Elevates upper lip, opens nostril
⑥ Anterior auricular muscle
Temporal fascia (anterior portion)
Helix of the ear
Pulls ear superiorly and anteriorly
⑦ Superior auricular muscle
Epicranial aponeurosis on side of head
Upper portion of auricle
Elevates ear
⑧ Posterior auricular muscle
Mastoid process
Convexity of concha of ear
Pulls ear superiorly and posteriorly
Calvaria
① Occipitofrontalis (frontal belly)
Palpebral fissure and nose
Ear
*There are no bony insertions for the muscles of facial expression.
**All muscles of facial expression are innervated by the facial nerve (CN VII) via temporal, zygomatic, buccal, mandibular, or cervical branches arising from the parotid
plexus (see pp. 568–569).
556
Fig. 39.10 Muscles of the mouth
G
A
J
F
A
Zygomaticus major and
minor, left lateral view.
H
B
Levator labii superioris and
depressor labii inferioris, left
lateral view.
C
Levator and depressor anguli
oris, left lateral view.
DBuccinator, left lateral view.
39 Muscles of the Skull & Face
D
S
K
L
E
Orbicularis oris, anterior view.
Table 39.2
F
Mentalis, anterior view.
Muscles of facial expression: Mouth and neck
Muscle
Origin
Insertion*
Main action(s)**
Zygomatic bone (lateral surface,
posterior part)
Skin at corner of the mouth
Pulls corner of mouth superiorly and laterally
Upper lip just medial to corner of the mouth
Pulls upper lip superiorly
Levator labii superioris
alaeque nasi (see Fig. 39.8C)
Maxilla (frontal process)
Alar cartilage of nose and upper lip
Elevates upper lip, opens nostril
③ Levator labii superioris
Maxilla (frontal process) and
infraorbital region
Skin of upper lip, alar cartilages of nose
Elevates upper lip, dilates nostril, raises angle of
the mouth
④ Depressor labii inferioris
Mandible (anterior portion of
oblique line)
Lower lip at midline; blends with muscle
from opposite side
Pulls lower lip inferiorly and laterally
⑤ Levator anguli oris
Maxilla (below infraorbital foramen)
Skin at corner of the mouth
Raises angle of mouth, helps form nasolabial furrow
⑥ Depressor anguli oris
Mandible (oblique line below canine,
premolar, and first molar teeth)
Skin at corner of the mouth; blends with
orbicularis oris
Pulls angle of mouth inferiorly and laterally
⑦ Buccinator
Mandible, alveolar processes of
maxilla and mandible, pterygomandibular raphe
Angle of mouth, orbicularis oris
Presses cheek against molar teeth, working with
tongue to keep food between occlusal surfaces
and out of oral vestibule; expels air from oral
cavity/resists distension when blowing
Unilateral: Draws mouth to one side
⑧ Orbicularis oris
Deep surface of skin
Superiorly: maxilla (median plane)
Inferiorly: mandible
Mucous membrane of lips
Acts as oral sphincter
• Compresses and protrudes lips (e.g., when
whistling, sucking, and kissing)
• Resists distension (when blowing)
Risorius (see pp. 552–553)
Fascia over masseter
Skin of corner of the mouth
Retracts corner of mouth as in grimacing
⑨ Mentalis
Mandible (incisive fossa)
Skin of chin
Elevates and protrudes lower lip
Skin over lower neck and upper
lateral thorax
Mandible (inferior border), skin over lower
face, angle of mouth
Depresses and wrinkles skin of lower face and
mouth; tenses skin of neck; aids in forced
depression of the mandible
Mouth
① Zygomaticus major
② Zygomaticus minor
Neck
Platysma (see pp. 552–553)
*There are no bony insertions for the muscles of facial expression.
**All muscles of facial expression are innervated by the facial nerve (CN VII) via temporal, zygomatic, buccal, mandibular, or cervical branches arising from its parotid plexus.
557
Head & Neck
Muscle Facts (II)
The muscles of mastication are located at various depths in the parotid
and infratemporal regions of the face. They attach to the mandible and
receive their motor innervation from the mandibular division of the
trigeminal nerve (CN V3). The muscles of the oral floor that aid in
­opening the mouth are found on in Table 37.3 on p. 516.
Muscles of mastication: Masseter and temporalis
Table 39.3
Muscle
Origin
Superficial layer: zygomatic arch
(anterior two thirds)
① Masseter
Deep layer: zygomatic arch
(posterior one third)
② Temporalis
Temporal fossa (inferior
temporal line)
Insertion
Innervation
Action
Mandibular angle (masseteric
tuberosity)
Mandibular n. (CN V3) via
masseteric n.
Elevates (entire muscle) and protrudes (superficial
fibers) the mandible
Coronoid process of
mandible (apex and medial
surface)
Mandibular n. (CN V3) via
deep temporal nn.
Vertical fibers: Elevate mandible
Horizontal fibers: Retract (retrude) mandible
Unilateral: Lateral movement of mandible (chewing)
Fig. 39.11 Masseter muscle
Fig. 39.12 Temporalis muscle
Left lateral view.
Left lateral view.
S
A
A
Schematic.
Zygomatic
arch
A
Schematic.
Frontal bone Parietal bone
Masseter
(deep layer)
Zygomatic arch (cut)
Temporalis
External
acoustic meatus
Mastoid process
Temporomandibular
joint (TMJ) capsule
Lateral
pterygoid
Styloid process
Masseter
(superficial layer)
B
Masseter with temporalis muscle.
558
Temporalis
Coronoid
process
Lateral (temporomandibular) lig.
Masseter
(cut)
B
Temporalis muscle. Removed: Masseter and zygomatic arch.
Table 39.4
Muscles of mastication: Pterygoid muscles
Muscle
Insertion
③ Superior head
Greater wing of sphenoid bone
(infratemporal crest)
Temporomandibular joint
(articular disk)
④ Inferior head
Lateral pterygoid plate (lateral
surface)
Mandible (condylar process)
⑤ Superficial head
Maxilla (tuberosity)
Lateral pterygoid
Medial pterygoid
Medial surface of lateral pterygoid
plate and pterygoid fossa
⑥ Deep head
Pterygoid tuberosity on
medial surface of the
mandibular angle
Innervation
Action
Mandibular n. (CN V3) via
lateral pterygoid n.
Bilateral: Protrudes mandible
(pulls articular disk forward)
Unilateral: Lateral movements
of mandible (chewing)
Mandibular n. (CN V3) via
medial pterygoid n.
Bilateral: Elevates mandible
with masseter; contributes
to protrusion.
Unilateral: small grinding
movements.
Fig. 39.13 Lateral pterygoid muscle
Superior
head
Inferior
head
Left lateral view.
Zygomatic
arch (cut)
D
Lateral
pterygoid
39 Muscles of the Skull & Face
Origin
Articular
disk
Condylar
head
F
B
Left lateral pterygoid
muscle. Removed: Coronoid
process and part of ramus of
mandible.
A
Schematic.
Styloid
process
Coronoid
process (cut)
Fig. 39.14 Medial pterygoid muscle
Left lateral view.
Pterygoid
process,
lateral plate
H
Medial
pterygoid
(superficial
head)
G
A
Schematic.
Left medial pterygoid
B
muscle. Removed: Coronoid process of mandible.
Medial
pterygoid
(deep head)
Mandibular
angle
Fig. 39.15 Masticatory muscle sling
Oblique posterior view.
Temporalis
Articular disk
D
F
G
H
A
Schematic.
Head of mandible
Masseter
Deep layer
Superficial
layer
Superior
head
Inferior
head
Lateral
pterygoid
Medial pterygoid
B
Revealed: Muscular sling formed by
the masseter and medial pterygoid
muscles that elevate the mandible.
559
40
Cranial Nerves
Head & Neck
Cranial Nerves: Overview
Fig. 40.1 Cranial nerves
Inferior (basal) view. The 12 pairs of cranial nerves (CN) are numbered
according to the order of their emergence from the brainstem. Note:
The sensory and motor fibers of the cranial nerves enter and exit the
I
Olfactory n.
II
Optic n.
brainstem at the same sites (in contrast to spinal nerves, whose sensory
and motor fibers enter and leave through posterior and anterior roots,
respectively). For fiber color code, see Table 40.1.
III
Oculomotor n.
VI
Abducent n.
V1
V2
IV
Trochlear n.
V
Trigeminal n.
VII
Facial n.
VIII
Vestibulocochlear n.
IX
Glossopharyngeal n.
X
Vagus n.
XII
Hypoglossal n.
560
XI
Accessory n.
V3
the cranial nerves may contain special fiber types associated with particular structures (e.g., auditory apparatus and taste buds). The cranial
nerve fibers originate or terminate at specific nuclei, which are similarly
classified as either general or special, somatic or visceral, and afferent or
efferent.
Classification of cranial nerve fibers and nuclei
Table 40.1
This color coding is used in subsequent chapters to indicate fiber and nuclei classifications.
Fiber type
Example
Fiber type
Example
General somatic efferent
(somatomotor function)
Innervate skeletal muscles
General somatic afferent
(somatic sensation)
Conduct impulses from skin, skeletal muscle
spindles
General visceral efferent
(visceromotor function)
Innervate smooth muscle of the viscera,
intraocular muscles, heart, salivary glands, etc.
Special somatic afferent
Conduct impulses from retina, auditory and
vestibular apparatuses
Special visceral efferent
Innervate skeletal muscles derived from
branchial arches
General visceral afferent
(visceral sensation)
Conduct impulses from viscera, blood vessels
Special visceral afferent
Conduct impulses from taste buds, olfactory
mucosa
Fig. 40.2 Cranial nerve nuclei
The sensory and motor fibers of cranial nerves III to XII originate and
terminate in the brainstem at specific nuclei.
Efferent (motor) nuclei
Oculomotor n.
nuclei (CN III)
Afferent (sensory) nuclei
Trigeminal n.
nuclei (CN V)
Nucleus of
trochlear n. (CN IV)
Table 40.2
40 Cranial Nerves
The cranial nerves contain both afferent (sensory) and efferent (­ motor)
axons that belong to either the somatic or the autonomic (visceral)
nervous system (see pp. 694–695). The somatic fibers allow interaction
with the environment, whereas the visceral fibers regulate the autonomic activity of internal organs. In addition to the general fiber types,
Cranial nerves
Cranial nerve
Origin
CN I: Olfactory n.
Telencephalon*
CN II: Optic n.
Diencephalon*
CN III: Oculomotor n.
CN IV: Trochlear n.
Functional fiber types
Mesencephalon
CN V: Trigeminal n.
Nucleus of
abducent n. (CN VI)
CN VI: Abducent n.
CN V
Pons
CN VII: Facial n.
Facial nucleus
(CN VII)
CN VII
CN VI
CN VIII
Salivatory nuclei
CN IX
CN X
Nucleus ambiguus
Dorsal motor
(vagal) nucleus
Nucleus of
hypoglossal n. (CN XII)
A
Posterior view with the cerebellum
removed.
Nucleus of solitary tract
CN III
CN IX: Glossopharyngeal n.
CN X: Vagus n.
CN XII: Hypoglossal n.
* The olfactory and optic nerves are extensions of the brain rather than true
nerves; they are therefore not associated with nuclei in the brainstem.
Visceral
oculomotor
nucleus
Nucleus of
trochlear n. (CN IV)
Nucleus of
oculomotor n.
CN V
Medulla oblongata
CN XI: Accessory n.
Spinal nucleus
of trigeminal n. (CN V)
Spinal nucleus of
accessory n. (CN XI)
CN VIII: Vestibulocochlear n.
Mesencephalic
nucleus
Motor nucleus
Principal (partial)
sensory nucleus
Inferior
salivatory
nucleus (CN IX)
Nucleus of abducent n. (CN VI)
Facial nucleus
CN VII
Superior salivatory nucleus
Dorsal vagal nucleus (CN X)
Nucleus
ambiguus
Nucleus of hypoglossal n. (CN XII)
Nucleus of solitary tract
Spinal nucleus of
trigeminal n. (CN V)
Midsagittal section, left lateral view.
B
Spinal nucleus of
accessory n. (CN XI)
561
Head & Neck
CN I & II: Olfactory & Optic Nerves
The olfactory and optic nerves are not true peripheral nerves but
­extensions (tracts) of the telencephalon and diencephalon, respec-
Olfactory
tract
Fig. 40.3 Olfactory nerve (CN I)
Olfactory
bulb
Olfactory
trigone
Fiber bundles in the olfactory mucosa pass from the nasal cavity
through the cribriform plate of the ethmoid bone into the anterior
cranial fossa, where they synapse in the olfactory bulb. Axons from
second-order ­afferent neurons in the olfactory bulb pass through the
olfactory tract and medial or lateral olfactory stria, terminating in the
cerebral cortex of the prepiriform area, in the amygdala, or in neighboring areas.
Prepiriform
area
Medial and
lateral
olfactory
stria
Ambient
gyrus
tively. They are therefore not associated with cranial nerve nuclei in the
brainstem.
Amygdala
Semilunar
gyrus
Diagonal
stria
A
Olfactory bulb and tract, inferior view.
Note: The amygdala and prepiriform
area are deep to the basal surface of
the brain.
Anterior perforated
substance
Medullary stria
of thalamus
Longitudinal striae
Interpeduncular
nucleus
Medial
olfactory
stria
Habenular
nuclei
Tegmental
nucleus
Olfactory
bulb
Olfactory
fibers
Reticular
formation
Uncus, with
amygdala
below
Dorsal
longitudinal
fasciculus
Lateral
olfactory stria
Olfactory bulb
(second-order sensory neurons)
Frontal
sinus
Olfactory
fibers (CN I,
first-order
sensory
neurons)
Nasal
septum
C
Olfactory fibers. Portion of left nasal septum and lateral wall of right nasal cavity,
left lateral view.
562
Olfactory
mucosa
Olfactory
tract
Cribriform
plate,
ethmoid
bone
Superior
concha
Nasal
septum
(cut)
Middle
concha
Prepiriform
area
B
Course of the olfactory nerve. Parasagittal
section, viewed from left side.
Optic
tract
Fig. 40.4 Optic nerve (CN II)
Lateral geniculate body
Lower
visual field
Optic
radiation
Upper
visual
field
The optic nerve passes from the eyeball through the optic canal into
the middle cranial fossa. The two optic nerves join below the base of
the diencephalon to form the optic chiasm, before dividing into the two
optic tracts. Each of these tracts divides into a lateral and medial root.
Many retinal cell ganglion axons cross the midline to the contralateral
side of the brain in the optic chiasm.
40 Cranial Nerves
Optic n.
(CN II)
Lateral
ventricle
Striate
area
Optic
chiasm
Meyer’s
loop
A
Optic nerve in the geniculate visual pathway,
left lateral view.
Optic
tract
Lateral
geniculate
body
Optic n.
(CN II)
Thalamus
Optic
chiasm
Optic
tract
Optic n.
(CN II)
Lateral
geniculate
body
Optic
chiasm
Medial
geniculate
body
Mesencephalon
B
Termination of the optic tract, left posterolateral view of the brainstem. The optic nerve
contains the axons of retinal ganglion cells,
which terminate mainly in the lateral geniculate
body of the diencephalon and in the mesencephalon (superior colliculus).
Optic
radiation
Occipital
pole
C
Course of the optic nerve, inferior (basal)
view.
Ophthalmic n.
(CN V1)
Optic n. (CN II)
passing through
optic canal
Optic
chiasm
Optic
tract
Optic
canal
Superior orbital
fissure
DOptic nerve in the left orbit, lateral view.
The optic nerve exits the orbit via the optic
canal. Note: The other cranial nerves (III, IV,
V1, and VI) entering the orbit do so via the
superior orbital fissure.
563
Head & Neck
CN III, IV & VI: Oculomotor, Trochlear & Abducent Nerves
Cranial nerves III, IV, and VI innervate the extraocular muscles (see
p. 605). Of the three, only the oculomotor nerve (CN III) contains both
somatic and visceral efferent fibers; it is also the only cranial nerve of
Fig. 40.5 Nuclei of the oculomotor, trochlear,
and abducent nerves
emerge from the dorsal side of the brainstem and, consequently,
has the longest intradural (intracranial) course of any cranial nerve.
The trochlear nerve (CN IV) is the only cranial nerve in which all the
fibers cross to the opposite side. It is also the only cranial nerve to
Cerebral peduncles
of mesencephalon
Oculomotor n.
(CN III)
Trochlear n. (CN IV)
Visceral
oculomotor
nucleus
Nucleus of
trochlear n.
Cerebral
aqueduct
Nucleus of
oculomotor n.
Pons
Abducent n.
(CN VI)
Tectum
Visceral
oculomotor
nucleus
Central gray
substance
Red nucleus
Nucleus of
abducent n.
Nucleus of oculomotor n.
Substantia
nigra
Medulla
oblongata
A
Emergence of the cranial nerves of the extraocular muscles. Anterior
view of the brainstem.
Table 40.3
the extraocular muscles to innervate multiple extra- and intraocular
muscles.
Cerebral crus of
cerebral peduncle
B
Oculomotor nerve nuclei. Transverse section, superior view.
Cranial nerves of the extraocular muscles
Course*
Fibers
Nuclei
Function
Effects of nerve injury
Somatic
efferent
Oculomotor
nucleus
Innervates:
• Levator palpebrae superioris
• Superior, medial, and inferior rectus
• Inferior oblique
Visceral
efferent
Visceral
oculomotor
(Edinger-Westphal)
nucleus
Synapse with neurons in ciliary
ganglia.
Innervates:
• Pupillary sphincter
• Ciliary muscle
Somatic
efferent
Nucleus of the
trochlear n.
Innervates:
• Superior oblique
• Diplopia
•A
ffected eye is higher and deviated medially
(dominance of inferior oblique)
Somatic
efferent
Nucleus of the
abducent n.
Innervates:
• Lateral rectus
• Diplopia
•M
edial strabismus (sp.) (due to unopposed
action of medial rectus)
Oculomotor nerve (CN III)
Runs anteriorly from mesencephalon
Complete oculomotor palsy (paralysis of extraand intraocular muscles):
• Ptosis (drooping of eyelid)
• Downward and lateral gaze deviation
• Diplopia (double vision)
• Mydriasis (pupil dilation)
• Accommodation difficulties (ciliary paralysis)
Trochlear nerve (CN IV)
Emerges from posterior surface of
brainstem near midline, courses
anteriorly around the cerebral peduncle
Abducent nerve (CN VI)
Follows a long extradural path**
* All three nerves enter the orbit through the superior orbital fissure; CN III and CN VI pass through the common tendinous ring of the extraocular muscles.
** The abducent nerve follows an extradural course; abducent nerve palsy may therefore develop in association with meningitis and subarachnoid hemorrhage.
564
Note: The oculomotor nerve supplies parasympathetic innervation
to the intraocular muscles and somatic motor innervation to most
of the extraocular muscles (also the levator palpebrae superioris). Its
parasympathetic fibers synapse in the ciliary ganglion. Oculomotor
nerve palsy may affect exclusively the parasympathetic or somatic
fibers, or both concurrently.
Short
ciliary
nerves
Right orbit.
Levator
palpebrae
superioris
Superior
rectus
Trochlea
Ciliary
ganglion
Common
tendinous
ring
CN III
Superior
oblique
Medial
rectus
40 Cranial Nerves
Fig. 40.6 Course of the nerves innervating the extraocular muscles
Mesencephalon
Lateral
rectus
(cut)
Pons
Inferior
oblique
CN IV
Pontomedullary
junction
Internal
carotid artery
and plexus
CN VI
Lateral
rectus (cut),
CN VI
CN III,
inferior
division
Sympathetic root
Inferior
(postganglionic fibers from rectus
superior cervical ganglion
via internal carotid plexus)
Parasympathetic root
(preganglionic fibers
from CN III)
A
Lateral view.
Supraorbital n. (cut)
Levator palpebrae superioris
Superior
ophthalmic v.
Levator palpebrae superioris
Superior
rectus
Lacrimal n.
Frontal n.
Trochlear n.
(CN IV)
Superior
oblique
Optic n.
(CN II)
Medial
rectus
Oculomotor n.
(CN III)
Superior
oblique
Superior
rectus
Medial
rectus
Lacrimal
gland
Inferior
rectus
Lateral
rectus
Trochlear n.
(CN IV)
Abducent n.
(CN VI)
Oculomotor n.
(CN III)
Optic n.
(CN II)
Inferior
rectus
Lateral
rectus
Abducent n.
(CN VI)
Inferior
oblique
B
Anterior view. CN II exits the orbit via the
optic canal, which lies medial to the superior orbital fissure (site of emergence of CN
III, IV, and VI).
C
Superior view of the opened orbit. Note
the relationship between the optic canal
and the superior orbital fissure.
565
Head & Neck
CN V: Trigeminal Nerve
The trigeminal nerve, the sensory nerve of the head, has three somatic
afferent nuclei: the mesencephalic nucleus, which receives proprioceptive fibers from the muscles of mastication; the principal (pontine)
sensory nucleus, which chiefly mediates touch; and the spinal nucleus,
which mediates pain and temperature sensation. The motor nucleus
supplies motor innervation to the muscles of mastication.
Fig. 40.7 Trigeminal nerve nuclei
Fig. 40.8 Divisions of the trigeminal nerve (CN V)
Trigeminal
ganglion
CN V 1
Right lateral view.
Mesencephalic
nucleus
CN V2
Ophthalmic
division (CN V1)
CN V3
Trigeminal n. (CN V)
Trigeminal
ganglion
Motor nucleus
Principal (pontine)
sensory nucleus
Maxillary
division (CN V2)
Spinal nucleus
Mesencephalic
nucleus
4th ventricle
Mandibular
division (CN V3)
Pons
Principal sensory
nucleus
Motor nucleus
A
Anterior view of the brainstem.
Trigeminal n.
(CN V)
B
Cross section through the pons, superior view.
A
Table 40.4
B
C
Trigeminal nerve (CN V)
Course
Exits from the middle
cranial fossa.
Ophthalmic division
(CN V1): Enters orbit
through superior
orbital fissure
Maxillary division
(CN V2): Enters
pterygopalatine fossa
through foramen
rotundum
Mandibular division
(CN V3): Passes
through foramen ovale
into infratemporal
fossa
Fibers
Nuclei
Function
•P
rincipal (pontine) sensory nucleus of the
trigeminal n.
•M
esencephalic nucleus of the trigeminal
n.
•S
pinal nucleus of the trigeminal n.
Innervates:
• Facial skin (A)
• Nasopharyngeal mucosa (B)
•T
ongue (anterior two thirds) (C)
Involved in the corneal reflex (reflex closure of eyelid)
Special
visceral
efferent
Motor nucleus of the trigeminal n.
Innervates (via CN V3):
• Muscles of mastication (temporalis, masseter,
medial and lateral pterygoids (D))
• Oral floor muscles (mylohyoid, anterior digastric)
• Tensor tympani
• Tensor veli palatini
Visceral
efferent
pathway*
• Lacrimal n. (CN V1) conveys parasympathetic fibers from CN VII along the zygomatic n. (CN V2)
to the lacrimal gland
• Lingual n. (CN V3) conveys parasympathetic fibers from CN VII (via the chorda tympani) to the
submandibular and sublingual glands
• Auriculotemporal n. (CN V3) conveys parasympathetic fibers from CN IX to the parotid gland
Visceral
afferent
pathway*
Gustatory (taste) fibers from CN VII (via chorda tympani) travel with the lingual n. (CN V3) to the
anterior two thirds of the tongue
Somatic
afferent
* Fibers of certain cranial nerves adhere to divisions or branches of the trigeminal nerve, by which they travel to their destination.
** All three divisions contribute to dural innervation in the anterior and middle cranial fossae.
566
D
Effects of nerve injury
• Sensory loss (traumatic
nerve lesions)
• Herpes zoster
ophthalmicus (varicellazoster virus); herpes
zoster of the face
Fig. 40.9 Course of the trigeminal nerve divisions
Right lateral view.
Anterior
ethmoidal n.
Supraorbital n.
Frontal n.
Supratrochlear n.
Superior
orbital fissure
Lacrimal n. (with gland)
Nasociliary n.
Infratrochlear n.
Recurrent meningeal
branch
Ophthalmic
division (CN V1)
Long ciliary nn.
Short ciliary nn.
Nasociliary (sensory)
root to ciliary ganglion
40 Cranial Nerves
Posterior
ethmoidal n.
Communicating
branch to
zygomatic n.
A
Ophthalmic division (CN V1). Partially
opened right orbit.
Ciliary ganglion
Zygomatic n. (with
communicating
branch)
Foramen rotundum
Maxillary division
(CN V2)
Infraorbital n.
Meningeal branch
Middle superior
alveolar n.
Ganglionic branches to
pterygopalatine ganglion
Anterior superior
alveolar
branches
Pterygopalatine
ganglion
Posterior superior
alveolar nn.
B
Maxillary division (CN V2). Partially opened
right maxillary sinus with the zygomatic
arch removed.
Inferior orbital
fissure
Meningeal
branch
Trigeminal
ganglion
Mandibular
Foramen
division (CN V3)
ovale
Deep
temporal nn.
Infraorbital
foramen
Buccal n.
Medial
pterygoid nn.
Auriculotemporal n.
Masseteric n.
Inferior dental
branches
Mylohyoid n.
Mandibular division (CN V3). Partially
C
opened mandible with the zygomatic
arch removed. Note: The mylohyoid nerve
branches from the inferior alveolar nerve
just before the mandibular foramen.
Lingual n.
Mandibular
foramen
Mental n.
(in mental
foramen)
Inferior alveolar n.
(in mandibular canal)
567
Head & Neck
CN VII: Facial Nerve
The facial nerve mainly conveys special visceral efferent (branchiogenic)
fibers from the facial nerve nucleus to the muscles of facial expression.
The other visceral efferent (parasympathetic) fibers from the superior
salivatory nucleus are grouped with the visceral afferent (gustatory)
fibers to form the nervus intermedius.
Fig. 40.10 Facial nerve nuclei
Abducent
nucleus
Internal genu
of facial n.
Nucleus of
solitary tract
Pons
Abducent
nucleus
Superior
salivatory nucleus
Superior
salivatory
nucleus
Facial
nucleus
Facial
nucleus
B
Cross section through
the pons, superior view.
Nervus
intermedius
Geniculate
ganglion
Nucleus
of solitary
tract
Stylomastoid
foramen
Internal acoustic
meatus
Geniculate
ganglion
Greater
petrosal n.
A
Anterior view of the brainstem.
Stapedial n.
Fig. 40.11 Branches of the facial nerve
Chorda
tympani
Right lateral view.
Internal acoustic meatus
Facial n.
(CN VII)
Stapedial n.
Geniculate
ganglion
Hiatus of canal for
greater petrosal n.
Trigeminal
ganglion
Stylomastoid
foramen
CN V1
CN V2
CN V3
Greater
petrosal n.
Petrotympanic
fissure
Stylomastoid
foramen
Facial
canal
Stylohyoid
Posterior
auricular n.
A
Facial nerve in the temporal bone.
568
Lingual n.
B
Branches.
Parotid plexus
Temporal
branches
Tympanic
membrane
Chorda
tympani
Posterior
auricular n.
Pterygopalatine
ganglion
Parotid
plexus
Zygomatic
branches
Posterior
auricular n.
Buccal
branches
Facial n.
Marginal
mandibular
branch
Digastric,
posterior belly
C
Parotid plexus.
Cervical branch
Table 40.5
Facial nerve (CN VII)
Fibers
Emerges in the
cerebellopontine angle
between the pons and olive;
passes through the internal
acoustic meatus into the
temporal bone (petrous part),
where it divides into:
• Greater petrosal n.
• Stapedial n.
• Chorda tympani
Certain special visceral
efferent fibers pass through
the stylomastoid foramen to
the skull base, forming the
intraparotid plexus
Effects of
nerve injury
Nuclei
Function
Facial nucleus
Innervate:
• Muscles of facial expression
• Stylohyoid
• Digastric (posterior belly)
• Stapedius
Visceral
efferent (parasympathetic)*
Superior salivatory
nucleus
Synapse with neurons in the pterygopalatine or submandibular ganglion.
Innervate:
• Lacrimal gland
• Small glands of nasal mucosa, hard and soft palate
• Submandibular gland
• Sublingual gland
• Small salivary glands of tongue (dorsum)
Special visceral
afferent*
Nucleus of the
solitary tract
Peripheral processes of fibers from geniculate ganglion form the chorda
tympani (gustatory fibers from tongue)
Somatic afferent
Sensory fibers from the auricle, skin of the auditory canal, and outer surface of the tympanic
membrane travel via CN VII to the principal sensory nucleus of the trigeminal n.
Special visceral
efferent
Peripheral facial
nerve injury:
paralysis of
muscles of facial
expression on
affected side
40 Cranial Nerves
Course
Associated
disturbances
of taste,
lacrimation,
salivation,
hyperacusis,
etc.
* Grouped to form nervus intermedius, which aggregates with the visceral efferent fibers from the facial n. nucleus.
Fig. 40.12 Course of the facial nerve
Right lateral view. This figure shows the distribution of all the fiber
types in Table 40.5. Visceral efferent (parasympathetic) and special
Trigeminal n.
Maxillary
division
Internal carotid
a. with internal
carotid plexus
Trigeminal
ganglion
visceral afferent (taste) fibers shown in blue and green respectively.
Postganglionic sympathetic fibers are shown in black.
Lacrimal gland
Via communicating
br. to lacrimal n.
Deep
petrosal n.
Geniculate
ganglion
Postganglionic
sympathetic and
parasympathetic
fibers
Nasal glands
Superior salivatory nucleus
Facial n.
Nucleus of the
solitary tract
Mandibular
division
Greater
petrosal n.
Pterygopalatine
ganglion
Taste buds of
soft palate
Submandibular
ganglion
Stylomastoid
foramen
Parotid
gland
Glandular brs.
Pterygoid canal
with n. of
pterygoid canal
Sublingual
gland
Lingual n.
Chorda
tympani
Submandibular
gland
569
Head & Neck
CN VIII: Vestibulocochlear Nerve
The vestibulochochlear nerve is a special somatic afferent nerve that
consists of two roots. The vestibular root transmits impulses from the
vestibular apparatus; the cochlear root transmits impulses from the
auditory apparatus.
Fig. 40.13 Vestibulocochlear nerve:
Vestibular part
Fig. 40.14 Vestibulocochlear nerve:
Cochlear part
Flocculus of
cerebellum
Anterior
cochlear nucleus
Direct fibers
to cerebellum
Superior
vestibular
nucleus
Vestibulocochlear n. (CN VIII)
Vestibular
root
Medial
vestibular
nucleus
Vestibular
ganglion
Lateral
vestibular
nucleus
Semicircular
canals
Inferior
vestibular
nucleus
Cochlear
root
A
Anterior view of the medulla oblongata and pons with cerebellum.
Superior
vestibular
nucleus
Medial
vestibular
nucleus
570
Vestibulocochlear n. (CN VIII)
Posterior
cochlear
nucleus
Anterior
cochlear
nucleus
B
Cross section through the upper
medulla oblongata.
Table 40.6
Cochlea with
spiral ganglia
A
Anterior view of the medulla oblongata and pons.
Lateral
vestibular
nucleus
B
Cross section through the upper
medulla oblongata.
Vestibulocochlear nerve (CN VIII)
Part
Course
Vestibular
part
Pass from the inner ear
through the internal
acoustic meatus to the
cerebellopontine angle,
where they enter the brain
Cochlear
part
Posterior
cochlear nucleus
Fibers
Special
somatic
afferent
Nuclei
Function
Effects of nerve injury
Superior, lateral, medial, and
inferior vestibular nuclei
Peripheral processes from the semicircular canals,
saccule, and utricle pass to the vestibular ganglion
and then to the four vestibular nuclei
Dizziness
Anterior and posterior
cochlear nuclei
Peripheral processes beginning at the hair cells of
the organ of Corti pass to the spiral ganglion and
then to the two cochlear nuclei
Hearing loss
Fig. 40.15 Vestibular and cochlear
(spiral) ganglia
Vestibular
root
Cochlear
root
Anterior
ampullary n.
ducts
Lateral
ampullary n.
Utricular
n.
Vestibulocochlear n.
(CN VIII)
Superior
Vestibular
part
Inferior ganglion
part
Saccular n.
Fig. 40.16 Vestibulocochlear nerve
in the temporal bone
Posterior semicircular canal
Anterior semicircular canal
Spiral
ganglia Cochlea
Posterior
ampullary n.
Utricle
40 Cranial Nerves
Note: The vestibular and cochlear roots are
still separate structures in the petrous
part of the temporal bone.
Semicircular
Saccule
Roof of
tympanic cavity
(tegmen tympani)
Cochlear duct
Geniculate
ganglion
Vestibular root (CN VIII)
Facial n. (CN VII)
Cochlear root (CN VIII)
Lateral semicircular canal
Greater petrosal n.
Lesser petrosal n.
Oval window
Semicanal of
tensor tympani
Internal carotid a.
Sigmoid sinus
(ghosted)
Pharyngotympanic
(auditory) tube
Internal
carotid plexus
Posterior wall of
tympanic cavity
Mastoid air cells
Anterior wall of
tympanic cavity
Chorda tympani
Facial n.
(in facial canal)
Round
window
Tympanic
plexus
Internal
jugular v.
Tympanic n.
Transverse crest
A
Medial wall of the tympanic cavity,
oblique sagittal section.
Greater
petrosal n.
Geniculate
ganglion
Facial n. (CN VII)
Nervus
intermedius
(from CN VII)
Internal
carotid a.
B
Cranial nerves in the
internal acoustic meatus.
Posterior oblique view of
the right meatus.
CN VIII
Cochlear n.
Vestibular n.
Sacculoampullary n.
Utriculoampullary n.
Posterior
ampullary n.
571
Head & Neck
CN IX: Glossopharyngeal Nerve
Fig. 40.17 Glossopharyngeal nerve nuclei
Nucleus
of the
solitary
tract
Inferior salivatory nucleus
Superior
part
Inferior
salivatory
nucleus
Nucleus
ambiguus
Inferior
part
Glossopharyngeal n.
Nucleus ambiguus
Superior
part
Nucleus
of the
solitary
tract
B
Cross section through the medulla oblongata, superior view. Not
shown: Nuclei of the trigeminal nerve.
Inferior
part
Jugular
foramen
Superior
ganglion
Tympanic n.
Inferior
ganglion
Br. to
carotid sinus
Br. to stylopharyngeus
Pharyngeal brs.
Spinal nucleus
of trigeminal n.
Fig. 40.18 Course of the glossopharyngeal nerve
Left lateral view. Note: Fibers from the vagus nerve (CN X) combine with
fibers from the glossopharyngeal nerve (CN IX) to form the pharyngeal
plexus and supply the carotid sinus.
A
Anterior view of the medulla oblongata.
Glossopharyngeal
n. (CN IX)
⑤
Stylopharyngeus
Vagus n.
(CN X)
①
Superior
ganglion
Inferior
ganglion
④
③
②
⑥
Br. to carotid
sinus
Table 40.7
572
Glossopharyngeal
nerve branches
①
Tympanic n.
②
Br. to carotid sinus
③
Br. to stylopharyngeus muscle
④
Tonsillar brs.
⑤
Lingual brs.
⑥
Pharyngeal brs.
Pharyngeal
plexus
Pharyngeal brs.
Carotid
sinus
Vagus n.
(CN X)
B
C
D
E
F
Glossopharyngeal nerve (CN IX)
Table 40.8
Course
Fibers
Emerges from
the medulla
oblongata;
leaves cranial
cavity through
the jugular
foramen
Effects of
nerve injury
Nuclei
Function
Visceral efferent
(parasympathetic)
Inferior salivatory
nucleus
Parasympathetic presynaptic fibers are sent to the otic ganglion;
postsynaptic fibers are distributed to
• Parotid gland (A)
• Buccal gland
• Labial gland
Special visceral efferent
(branchiogenic)
Nucleus ambiguus
Innervate:
• Constrictor muscles of the pharynx (pharyngeal branches join with the
vagus nerve to form the pharyngeal plexus)
• Stylopharyngeus
Visceral afferent
Nucleus of the solitary
tract (inferior part)
Receive sensory information from
• Chemoreceptors in the carotid body (B)
• Pressure receptors in the carotid sinus
Special visceral afferent
Nucleus of the solitary
tract (superior part)
Receives sensory information from the posterior third of the tongue (via the
inferior ganglion) (C)
Spinal nucleus of
trigeminal nerve
Peripheral processes of the intracranial superior ganglion or the extracranial
inferior ganglion arise from
• Tongue, soft palate, pharyngeal mucosa, and tonsils (D, E)
• Mucosa of the tympanic cavity, internal surface of the tympanic
membrane, pharyngotympanic tube (tympanic plexus) (F)
• Skin of the external ear and auditory canal (blends with the vagus n.)
Somatic afferent
Fig. 40.19 Glossopharyngeal nerve in the tympanic cavity
Left anterolateral view. The tympanic nerve contains visceral efferent
(presynaptic parasympathetic) fibers for the otic ganglion, as well as
somatic afferent fibers for the tympanic cavity and pharyngotympanic
tube. It joins with sympathetic fibers from the internal carotid plexus
(via the caroticotympanic nerve) to form the tympanic plexus.
Tubarian br.
40 Cranial Nerves
A
Isolated lesions
of CN IX are
rare. Lesions
are generally
accompanied
by lesions of
CN X and CN XI
(cranial part),
as all three
emerge jointly
from the jugular
foramen and are
susceptible to
injury in basal
skull fractures.
Fig. 40.20 Visceral efferent (parasympathetic)
fibers of CN IX
Tympanic n.
Glossopharyngeal n.
(CN IX)
Trigeminal n. (CN V)
Caroticotympanic n.
Lesser
petrosal n.
Mandibular
division
(CN V3)
Tympanic
plexus
Auriculotemporal n.
Pharyngotympanic
(auditory) tube
Parotid gland
Lesser
petrosal n.
Otic
ganglion
Postganglionic parasympathetic fibers (run a short
distance with the
auriculotemporal n.)
Internal carotid
plexus
Tympanic
canaliculus with
tympanic n.
Promontory of
labyrinthine wall
Superior
ganglion
Glossopharyngeal n.
(CN IX)
Inferior
ganglion
Tympanic
plexus
573
Head & Neck
CN X: Vagus Nerve
Fig. 40.21 Vagus nerve nuclei
Dorsal vagal
nucleus
Nucleus
of the
solitary
tract
Nucleus ambiguus
Superior part
Nucleus of the
solitary tract
Inferior part
Dorsal vagal
nucleus
Superior
part
Inferior
part
Spinal nucleus of
trigeminal n.
Superior ganglion
Nucleus
ambiguus
Inferior ganglion
Olive
Pharyngeal br.
Jugular
foramen
Superior
laryngeal n.
Spinal nucleus
of trigeminal n.
A
Anterior view of the
medulla oblongata.
Table 40.9
Course
Emerges from
the medulla
oblongata;
leaves the
cranial cavity
through
the jugular
foramen. CN X
has the most
extensive
distribution
of all the
cranial nerves
(vagus =
“vagabond”),
consisting
of cranial,
cervical,
thoracic (see
p. 87), and
abdominal
(see p. 215)
parts.
574
Cross section through the medulla oblongata, superior view.
B
Vagus nerve (CN X)
Fibers
Nuclei
Function
Nucleus
ambiguus
Innervate:
• Pharyngeal muscles (via pharyngeal
plexus with CN IX)
• Muscles of the soft palate
• Laryngeal muscles (superior laryngeal
n. supplies the cricothyroid; inferior
laryngeal n. supplies all other
laryngeal muscles)
Dorsal vagal
nucleus
Synapse in prevertebral or intramural
ganglia. Innervate smooth muscle and
glands of
• Thoracic viscera (A)
• Abdominal viscera (A)
Somatic
afferent
Spinal nucleus
of trigeminal
nerve
Superior (jugular) ganglion receives
peripheral fibers from
• Dura in posterior cranial fossa (C)
• Skin of ear (D), external auditory
canal (E)
Special
visceral
afferent
Nucleus of
solitary tract
(superior part)
Inferior nodose ganglion receives
peripheral processes from
• Taste buds on the epiglottis and root
of the tongue (F)
Nucleus of
solitary tract
(inferior part)
Inferior ganglion receives peripheral
processes from
• Mucosa of lower pharynx at its
esophageal junction (G)
• Laryngeal mucosa above (superior
laryngeal n.) and below (inferior
laryngeal n.) the vocal fold (G)
• Pressure receptors in the aortic arch (B)
• Chemoreceptors in the para-aortic
body (B)
• Thoracic and abdominal viscera (A)
Special
visceral
efferent
(branchiogenic)
Visceral
efferent
(parasympathetic)
Visceral
afferent
Effects of
nerve injury
B
The recurrent
laryngeal
n. supplies
visceromotor
innervation to
the only muscle
abducting the
vocal cords,
the posterior
cricoarytenoid.
Unilateral
destruction of
this nerve leads
to hoarseness;
bilateral
destruction
leads to
respiratory
distress
(dyspnea).
A
C
D
E
F
G
40 Cranial Nerves
Fig. 40.22 Course of the vagus nerve
The vagus nerve gives off four major branches in the neck. The inferior
laryngeal nerves are the terminal branches of the recurrent laryngeal
nerves. Note: The left recurrent laryngeal nerve hooks around the aortic
arch, while the right nerve hooks around the subclavian artery.
Table 40.10
Vagus n.
(CN X)
①
Vagus nerve branches
in the neck
①
Pharyngeal brs.
②
Superior laryngeal n.
3R
Right recurrent laryngeal n.
3L
Left recurrent laryngeal n.
④
Cervical cardiac brs.
②
Internal br.
(internal laryngeal n.)
External br.
(external laryngeal n.)
Cricothyroid
Right inferior
laryngeal n.
Left inferior
laryngeal n.
Subclavian a.
3R
Brachiocephalic
trunk
3L
④
Vagus n.
(CN X)
①
②
Internal br. (sensory)
Cricothyroid
Branches of the vagus nerve in the neck. Anterior view.
A
External br. (motor)
B
Innervation of the pharyngeal and laryngeal muscles. Left lateral view.
575
Head & Neck
CN XI & XII: Accessory & Hypoglossal Nerves
The traditional “cranial root” of the accessory nerve (CN XI), with its cell
bodies found in the nucleus ambiguus, is now considered a part of the
vagus nerve (CN X) that travels with the spinal root of CN XI for a short
distance before splitting off. The cranial fibers are therefore part of CN
X distributed via the vagus nerve after traveling briefly with the spinal
root of CN XI. The spinal root fibers, arising from the spinal nucleus
of the accessory nerve are now considered to be the accessory nerve,
continue on as the accessory nerve (CN XI).
Fig. 40.23 Accessory nerve
Posterior view of the brainstem with the cerebellum removed. Note: For didactic reasons,
the muscles are displayed from the right side.
Jugular
foramen
Vagus n. (CN X)
Corticobulbar
fibers
Nucleus
ambiguus
Fig. 40.24 Accessory nerve lesions
Lesion of the right accessory nerve.
Foramen
magnum
Cranial
root
Accessory n.
(CN XI)
Spinal
root
Sternocleidomastoid
Spinal nucleus of
accessory n.
Trapezius
B
Sternocleidomastoid paralysis,
right anterolateral view. See
Table 40.11 (below) for clinical
correlation explanation.
Trapezius paralysis, posterior view.
A
See Table 40.11 (below) for clinical correlation explanation.
Table 40.11
Accessory nerve (CN XI)*
Course
The spinal root emerges from the spinal
cord (at the level of C1–C5/6), passes
superiorly, and enters the skull through
the foramen magnum, where it joins
with the cranial root arising from the
medulla oblongata. Both roots leave the
skull through the jugular foramen. Within
the jugular foramen, fibers from the
cranial root pass to the vagus n. (internal
branch). The spinal portion descends to
the nuchal region as the external branch.
Fibers
Nuclei
Function
Effects of nerve injury
Special
visceral
efferent
Nucleus
ambiguus
(caudal part)
Join CN X and are distributed
with the recurrent laryngeal n.
Innervate:
• All laryngeal muscles (except
cricothyroid)
Spinal nucleus
of accessory n.
Form the external branch of the
accessory n.
Innervate:
• Trapezius
• Sternocleidomastoid
Trapezius paralysis: drooping of shoulder on affected
side and difficulty raising arm above horizontal plane.
This paralysis is a concern during neck operations (e.g.,
lymph node biopsies). An injury of the accessory n. will
not result in complete trapezius paralysis (the muscle
is also innervated by segments C3 and C4).
Sternocleidomastoid paralysis: torticollis (wry neck, i.e.,
difficulty turning head). Unilateral lesions cause flaccid
paralysis (the muscle is supplied exclusively by the
accessory n.). Bilateral lesions make it difficult to hold
the head upright.
Somatic
efferent
*See text at top of page, and Table 40.2, regarding new data on cranial fibers of CN XI.
576
Fig. 40.25 Hypoglossal nerve
Precentral
gyrus
Corticobulbar
fibers
Fig. 40.26 Hypoglossal nerve nuclei
40 Cranial Nerves
Posterior view of the brainstem with the cerebellum removed.
Note: C1, which innervates the thyrohyoid and geniohyoid, runs
briefly with the hypoglossal nerve.
Styloglossus
Vagus n.
Note: The nucleus of the hypoglossal nerve
is innervated by cortical neurons from the
contralateral side.
C1
Nucleus of
the hypoglossal n.
Hypoglossal n.
(CN XII)
Hypoglossal
canal
Hypoglossal n.
Genioglossus
Hyoglossus
Thyrohyoid
Nucleus of
the hypoglossal n.
Foramen
magnum
Hypoglossal
canal
C1 spinal n.
Fig. 40.27 Hypoglossal nerve lesions
A
Anterior view.
Superior view. See Table 40.12 below for clinical correlation
­explanation.
Hypoglossal trigone
(in rhomboid fossa)
Paralyzed
genioglossus
Nucleus of the
hypoglossal n.
Normal genioglossus
A
muscles.
Olive
B
Unilateral nuclear or
peripheral lesion.
B
Cross section through the medulla
oblongata.
Table 40.12
Tongue
Hypoglossal nerve (CN XII)
Course
Fibers
Nuclei
Function
Effects of nerve injury
Emerges from the medulla oblongata,
leaves the cranial cavity through the
hypoglossal canal, and descends laterally
to the vagus nerve. CN XII enters the root
of the tongue above the hyoid bone.
Somatic
efferent
Nucleus of
the hypoglossal n.
Innervates:
• Intrinsic and extrinsic
muscles of the tongue
(except the palatoglossus,
supplied by CN X)
Central hypoglossal paralysis (supranuclear): tongue deviates
away from the side of the lesion.
Nuclear or peripheral paralysis: tongue deviates toward the
affected side (due to preponderance of muscle on healthy side)
Flaccid paralysis: both nuclei injured; tongue cannot be protruded.
577
Head & Neck
Autonomic Innervation
Fig. 40.28 Parasympathetic
nervous system (cranial part):
Overview
Ciliary
ganglion
There are four parasympathetic nuclei in
the brainstem. The visceral efferent fibers
of these nuclei travel along particular cranial nn., listed below.
• Visceral oculomotor (Edinger–Westphal)
nucleus: oculomotor n. (CN III)
• Superior salivatory nucleus: facial n.
(CN VII)
• Inferior salivatory nucleus: glossopharyngeal n. (CN IX)
• Dorsal vagal nucleus: vagus n. (CN X)
Visceral
occulomotor
(EdingerWestphal)
nucleus
The preganglionic parasympathetic fibers
often travel with multiple cranial nn. to
reach their target organs. The vagus n.
supplies all of the thoracic and abdominal
organs as far as a point near the left colic
flexure.
Note: The sympathetic fibers to the head
travel along the arteries to their target
organs.
III
Submandibular
ganglion
Superior
salivatory
nucleus
VII
Inferior
salivatory
nucleus
Dorsal
motor
nucleus of
the vagus
Pterygopalatine
ganglion
IX
X
Thoracic
ganglia
Otic
ganglion
Abdominal
ganglia
Parasympathetic preganglionic fibers
Parasympathetic postganglionic fibers
Table 40.13
Parasympathetic ganglia in the head
Nucleus
Path of presynaptic fibers
Ganglion
Postsynaptic fibers
Target organs
Edinger-Westphal
nucleus
Oculomotor n. (CN III)
Ciliary ganglion
Short ciliary nn. (CN V1)
Ciliary muscle (accommodation)
Pupillary sphincter (miosis)
Nervus intermedius (CN VII root)
→ greater petrosal n. → n. of
pterygoid canal
Pterygopalatine
ganglion
• Maxillary n. (CN V2) → zygomatic n. →
anastomosis → lacrimal n. (CN V1)
• Orbital branches
• Posterior superior nasal brs.
• Nasopalatine nn.
• Greater and lesser palatine nn.
• Lacrimal gland
• Glands of nasal cavity and paranasal
sinuses
• Glands of gingiva
• Glands of hard and soft palate
• Glands of pharynx
Nervus intermedius (CN VII root)
→ chorda tympani → lingual n.
(CN V3)
Submandibular
ganglion
Glandular branches
Submandibular gland
Sublingual gland
Inferior salivatory
nucleus
Glossopharyngeal n. (CN IX) →
tympanic n. → lesser petrosal n.
Otic ganglion
Auriculotemporal n. (CN V3)
Parotid gland
Dorsal motor
(vagal) nucleus
Vagus n. (X)
Ganglia near
organs
Fine fibers in organs, not individually named
Thoracic and abdominal viscera
Superior salivatory
nucleus
→ = is continuous with
578
Long ciliary n.
(CN V1)
Pupillary dilation
Accommodation
Nasociliary n.
(CN V1)
N. of pterygoid
canal
Pterygoid
canal
40 Cranial Nerves
Ciliary ganglion
Blood vessels
Sweat glands
Pterygopalatine
ganglion
Deep petrosal n.
(CN VII)
Vasomotor
innervation
Internal carotid a.
plexus
Facial a.
plexus
Superior cervical
ganglion
Vasomotor
innervation
Sympathetic postganglionic
External carotid a.
plexus
Fig. 40.29 Sympathetic innervation of the head
Sympathetic preganglionic neurons of the head originate in the lateral
horn of the spinal cord (TI–T3). They exit into the sympathetic trunk and
ascend to synapse in the superior cervical ganglion. Postganglionic neurons then travel with arterial plexuses. Postganglionic fibers that travel
with the carotid plexus (on the internal carotid artery) join with the nasociliary nerves (of CN V1) and then the long ciliary nerves to reach the
dilator pupillae muscle (pupillary dilation); other postganglionic fibers
travel through the ciliary ganglion (without synapsing) to reach the ciliary muscle to participate in accomodation. Still other postganglionic fibers from the carotid plexus leave with the deep petrosal nerve, which
Table 40.14
Nucleus
Lateral horn of
spinal cord
(TI–L2)
joins with the greater petrosal nerve (CN VII), to form the nerve of the
pterygoid canal (vidian nerve). This nerve travels to the pterygopalatine
ganglion where it distributes fibers via branches of the maxillary nerve to
the glands of the nasal cavity, maxillary sinus, hard and soft palate, gingiva, and pharynx, and to sweat glands and blood vessels in the head.
Postganglionic fibers from the superior cervical ganglion that travel with
the facial artery plexus pass through the submandibular ganglion (without synapsing) to the submandibular and sublingual glands. Other postganglionic fibers travel with the middle meningeal plexus, through the
otic ganglion (without synapsing), to the parotid gland.
Sympathetic fibers in the head
Path of presynaptic fibers
Enter sympathetic trunk and ascend
to superior cervical ganglion
Ganglion
Superior cervical
ganglion
Postsynaptic fibers
Target organs
ICA plexus → nasociliary n. (CN V1) → long ciliary
nn. (CN V1)
Dilator pupillae muscle (mydriasis)
Postganglionic fibers → ciliary ganglion*→ short
ciliary nn. (limited number of fibers)
Ciliary muscle (sparse
sympathetic fibers contributing
to accommodation)
ICA plexus → deep petrosal n. → n. of pterygoid
canal → pterygopalatine ganglion* → branches of
maxillary n. (CN V2)
Glands of nasal cavity
Sweat glands
Blood vessels
Facial a. plexus → submandibular ganglion*
Submandibular gland
Sublingual gland
External carotid a. plexus
Parotid gland
*passes through without synpasing; → = is continuous with
ICA, internal carotid a.
579
41
Neurovasculature of the Skull & Face
Head & Neck
Innervation of the Face
Fig. 41.1 Motor innervation of the face
Left lateral view. Five branches of the facial nerve (CN VII) provide
motor innervation to the muscles of facial expression. The mandibular
division of the trigeminal nerve (CN V3) supplies motor innervation to
the muscles of mastication.
Temporal brs.
Parotid
plexus
Zygomatic brs.
Posterior
auricular n.
Buccal brs.
Facial n. (CN VII)
Marginal
mandibular br.
Cervical br.
A
Motor innervation of the muscles of facial expression.
Maxillary division (CN V2)
Mandibular division (CN V3,
exits via foramen ovale)
Trigeminal
ganglion
Ophthalmic
division (CN V1)
Trigeminal n. (CN V)
Meningeal br.
Deep temporal nn.
(to temporalis)*
N. to lateral pterygoid
and lateral pterygoid*
Buccinator
Inferior alveolar n.
Auriculotemporal n.
Buccal n.
Parotid brs.
Lingual n.
N. to masseter
and masseter*
N. to medial pterygoid
and medial pterygoid*
B
Motor innervation of the muscles of mastication (*).
580
Fig. 41.2 Sensory innervation of the face
Trigeminal n.
(CN V)
Infraorbital n.
(from CN V2)
Greater occipital n. (C2),
posterior ramus
Maxillary
division
Spinal nn.,
posterior rami
Mandibular
division
Transverse
cervical n.
Mental n.
(from CN V3)
Lesser occipital n.
(C2) anterior ramus
Supraclavicular nn.
Great auricular n.
(C2, C3), anterior rami
A
Sensory branches of the trigeminal nerve, anterior view. The sensory
branches of the three divisions emerge from the supraorbital, infraorbital, and mental foramina, respectively.
Maxillary division
(CN V2)*
B
Cutaneous innervation of the head and neck, left lateral view. The
occiput and nuchal regions are supplied by the posterior rami (blue)
of the spinal nerves (the greater occipital nerve is the posterior
ramus of C2).
41 Neurovasculature of the Skull & Face
Ophthalmic
division
Supraorbital n.
(from CN V1)
Ophthalmic division
(CN V1)*
Supraorbital n.*
Supratrochlear n.*
Trigeminal
ganglion
Pterygopalatine
ganglion
Mandibular division
(CN V3)
Infraorbital n.*
Auriculotemporal n.*
Masseteric n.
Buccal n.*
Lingual n.*
Inferior
alveolar n.*
Mental n.*
Mylohyoid n.
C
Divisions of the trigeminal nerve, left lateral view.
*Indicates sensory nn.
581
Head & Neck
Arteries of the Head & Neck
chiefly supplies the brain (p. 688), although its branches anastomose with
the external carotid in the orbit and nasal septum. The external carotid is
the major supplier of structures of the head and neck.
The head and neck are supplied by branches of the common carotid
artery. The common carotid splits at the carotid bifurcation into two
branches: the internal and external carotid arteries. The internal carotid
Supraorbital a.
Fig. 41.3 Internal carotid artery
Supratrochlear a.
Left lateral view. The most important extracerebral branch of the internal carotid artery
is the ophthalmic artery, which supplies the
upper nasal septum (p. 620) and the orbit
(p. 608). See pp. 688–689 for the arteries of
the brain.
Ophthalmic a.
Posterior
communicating a.
Internal
carotid a.
Dorsal
nasal a.
Basilar a.
Posterior
ethmoidal a.
External
carotid a.
Ophthalmic a.
Internal
carotid a.
Angular a.
Internal carotid a.
External carotid a.
Facial a.
Common
carotid a.
Superior
thyroid a.
Vertebral a.
Subclavian a.
Vertebral a.
Schematic.
A
Ophthalmic a.
Anterior
cerebral a.
Subclavian a.
Middle
cerebral a.
Anterior choroidal a.
Posterior communicating a.
Superior hypophyseal a.
Basal tentorial br.
Cerebral
part
Marginal tentorial br.
Cavernous
part
Inferior
hypophyseal a.
Trigeminal ganglion br.
Neural br.
Meningeal br.
Cavernous
sinus br.
A. of
pterygoid canal
Parts and branches of the internal carotid
B
artery.
582
Carotid
bifurcation
Petrous part
Caroticotympanic aa.
Cervical part
Course of the internal carotid artery.
C
Clinical box 41.1
The carotid artery is often affected by atherosclerosis, a hardening of arterial
walls due to plaque formation. The examiner can determine the status of the
arteries using ultrasound. Note: The absence of atherosclerosis in the carotid
A
Common carotid artery with “normal” flow.
artery does not preclude coronary heart disease or atherosclerotic changes in
other locations.
B
Calcified plaque in the carotid bulb.
41 Neurovasculature of the Skull & Face
Carotid artery atherosclerosis
Fig. 41.4 External carotid artery: Overview
Left lateral view.
Terminal
branches
Posterior
branches
Angular a.
Medial
branch
Anterior
branches
A
Schematic of the external carotid artery.
Superficial
temporal a.
Posterior
auricular a.
Superior
labial a.
Maxillary a.
Occipital a.
Ascending
pharyngeal a.
Inferior
labial a.
Facial a.
Facial a.
Table 41.1
Group
Branches of the
external carotid artery
Artery
Superior thyroid a.
Anterior (p. 584)
Lingual a.
Medial (p. 584)
Ascending pharyngeal a.
Facial a.
Posterior (p. 585)
Terminal (p. 585)
Occipital a.
Internal carotid a.
Lingual a.
Carotid bifurcation
with carotid body
Superior thyroid a.
Superior laryngeal a.
Vertebral a.
External carotid a.
Left common carotid a.
Thyrocervical a.
Left subclavian a.
Posterior auricular a.
Maxillary a.
Superficial temporal a.
B
Course of the external carotid artery.
583
Head & Neck
External Carotid Artery: Anterior, Medial & Posterior Branches
Fig. 41.5 Anterior and medial branches
Ophthalmic a.
Left lateral view. The arteries of the anterior aspect supply the
anterior structures of the head and neck, including the orbit (p. 606),
ear (p. 632), larynx (p. 530), pharynx (p. 654), and oral cavity. Note:
The angular artery anastomoses with the dorsal nasal artery of the
internal carotid (via the ophthalmic artery).
Angular a.
Internal carotid a.
Ascending
pharyngeal a.
Facial a.
Lingual a.
Superior
thyroid a.
A
Arteries of the anterior and medial
branches. The copious blood supply
to the face makes facial injuries bleed
profusely but heal quickly. There are
extensive anastomoses ­between
branches of the external carotid
­artery and between the external
carotid artery and branches of the
ophthalmic artery.
Dorsal nasal a.*
Angular a.
Superficial
temporal a.
Infraorbital a.
Maxillary a.
Superior labial a.
Ascending
pharyngeal a.
Tonsillar a.
Ascending
palatine a.
Inferior labial a.
Facial a.
Mental a.
Lingual a.
Internal carotid a.
Submental a.
Glandular
branches
Left common carotid a.
Superior
thyroid a.
B
Course of the anterior
and medial branches.
584
*Branch of ophthalmic a.
Fig. 41.6 Posterior branches
Superficial
temporal a.
Posterior
auricular a.
Occipital a.
External
carotid a.
Vertebral a.
Left common
carotid a.
A
Arteries of the posterior branch.
Posterior
branch
Occipital
branches
Superficial
temporal a.
41 Neurovasculature of the Skull & Face
Left lateral view. The posterior branches of the external carotid artery
supply the ear (p. 632), posterior skull (p. 594), and posterior neck
muscles (p. 541).
Occipital a.
Descending
branch
Maxillary a.
Posterior
auricular a.
Ascending
pharyngeal a.
Occipital a.
Facial a.
Lingual a.
Internal carotid a.
Superior
thyroid a.
Table 41.2
Branch
Anterior brs.
Medial br.
Posterior brs.
External carotid a.
Left common carotid a.
B
Course of the posterior branches.
Anterior, medial, and posterior branches of the external carotid artery
Artery
Divisions and distribution
Superior thyroid a.
Glandular br. (to thyroid gland); superior laryngeal a.; sternocleidomastoid br.
Lingual a.
Dorsal lingual brs. (to base of tongue, palatoglossal arch, tonsil, soft palate and epiglottis); sublingual a. (to
sublingual gland, tongue, oral floor, oral cavity); sublingual br. to the sublingual gland; deep lingual a.
Facial a.
Ascending palatine a. (to pharyngeal wall, soft palate, pharyngotympanic tube); tonsillar branch (to palatine
tonsils); submental a. (to oral floor, submandibular gland); labial aa.; angular a. (to nasal root)
Ascending pharyngeal a.
Pharyngeal brs.; inferior tympanic a. (to mucosa of inner ear); posterior meningeal a.
Occipital a.
Occipital brs.; descending br. (to posterior neck muscles)
Posterior auricular a.
Stylomastoid a. (to facial n. in facial canal); posterior tympanic a.; auricular br.; occipital br.;
parotid br.
For terminal brs., see Table 41.3 (p. 586).
585
Head & Neck
External Carotid Artery: Terminal Branches
The terminal branches of the external carotid artery consist of two major
arteries: superficial temporal and maxillary. The superficial temporal
artery supplies the lateral skull. The maxillary artery is a major artery for
internal structures of the face.
Fig. 41.7 Superficial temporal artery
Left lateral view. Inflammation of the superficial temporal artery due to
temporal arteritis can cause severe headaches. The course of the frontal
branch of the artery can often be seen superficially under the skin of
elderly patients.
Parietal
bone br.
Frontal br.
Superficial
temporal a.
Maxillary a.
External
carotid a.
Middle
temporal a.
Zygomaticoorbital a.
Transverse
facial a.
Left common
carotid a.
Superficial
temporal a.
Maxillary a.
External
carotid a.
A
Arteries of the terminal branch.
Table 41.3
Branch
External
carotid a.
B
Course of the superficial temporal artery.
Terminal branches of the external carotid artery
Artery
Divisions and distribution
Superficial temporal a.
Transverse facial a. (to soft tissues below the zygomatic arch); frontal brs.; parietal brs.; zygomatico-orbital a.
(to lateral orbital wall)
Mandibular part
Inferior alveolar a. (to mandible, teeth, gingiva); middle meningeal a.; deep auricular a. (to temporomandibular
joint, external auditory canal); anterior tympanic a.
Pterygoid part
Masseteric a.; deep temporal brs.; pterygoid brs.; buccal a.
Posterosuperior alveolar a. (to maxillary molars, maxillary sinus, gingiva); infraorbital a. (to maxillary alveoli)
Maxillary a.
Pterygopalatine
part
Descending palatine a.
Sphenopalatine a.
* Parts not shown here. See Fig 41.27 (p. 599) and Table 41.8 (p. 601).
586
Greater palatine a. (to hard palate)
Lesser palatine a. (to soft palate, palatine tonsil, pharyngeal wall)
Lateral posterior nasal aa. (to lateral wall of nasal cavity, conchae)
Posterior septal brs. (to nasal septum)
Fig. 41.8 Maxillary artery
Left lateral view. The maxillary artery consists of three parts: mandibular (blue), pterygoid (green), and pterygopalatine (yellow).
Clinical box 41.2
The middle meningeal artery supplies the meninges and overlying
calvaria. Rupture of the artery (generally due to head trauma) results in
an epidural hematoma.
Middle
meningeal a.
Posterior
superior
alveolar a.
Frontal br.
Anastomotic
br. with
lacrimal a.
Parietal br.
Deep
auricular a.
Buccal a.
Anterior
tympanic a.
41 Neurovasculature of the Skull & Face
Middle meningeal artery
Inferior alveolar a.
A
Divisions of the maxillary artery.
Middle meningeal a.
Petrous br.
A
Right middle meningeal artery, medial view of opened skull.
Calvaria
Infraorbital a.
Ruptured middle
meningeal a.
Sphenopalatine a.
Deep temporal aa.
Pterygoid br.
Fracture
Epidural
B
hematoma.
Schematic
­coronal section.
Arachnoid
Dura mater
Epidural
hematoma
Sphenopalatine artery
Middle
meningeal a.
Maxillary a.
Masseteric a.
Buccal a.
Mylohyoid br.
Mental br.
The sphenopalatine artery supplies the wall of the nasal cavity. Excessive
nasopharyngeal bleeding from the branches of the sphenopalatine artery
may necessitate ligation of the maxillary artery in the pterygopalatine fossa.
Lateral posterior
nasal aa.
Posterior
septal brs.
Inferior
alveolar a.
Sphenopalatine a.
Anterior and
posterior
superior
alveolar aa.
Descending
palatine a.
B
Course of the maxillary artery.
Lesser palatine a.
Greater palatine a.
Lateral wall of right nasal cavity, medial view.
C
587
Head & Neck
Veins of the Head & Neck
Fig. 41.9 Veins of the head and neck
Left lateral view. The veins of the head and neck drain into the brachiocephalic vein. Note: The left and right brachiocephalic veins are not
symmetrical.
Superior sagittal sinus
Table 41.4
Principal superficial veins
Vein
Region drained
Location
Internal jugular v.
Interior of skull (including brain)
Within carotid sheath
External jugular v.
Superficial head
Anterior jugular v.
Neck, portions of head
Within superficial
cervical fascia
Superficial
temporal v.
Confluence
of the sinuses
Cavernous
sinus
Transverse
sinus
Sigmoid sinus
External
Facial v.
Internal
Supraorbital v.
Jugular vv.
Anterior
Suprascapular v.
Left brachiocephalic v.
Subclavian v.
Supratrochlear v.
A
Principal veins of the head and neck.
Superior
and inferior
ophthalmic vv.
Superficial
temporal v.
Pterygoid plexus
(deep temporal vv.)
Angular v.
Maxillary v.
Occipital v.
Posterior auricular v.
Facial v.
Retromandibular v.
Inferior
labial v.
Superior thyroid v.
Submental v.
Internal jugular v.
External jugular v.
Anterior
jugular v.
B
Superficial veins of the head and neck.
Note: The course of the veins is highly
variable.
588
Left brachiocephalic v.
Suprascapular v.
Subclavian v.
Fig. 41.10 Deep veins of the
head
Deep
Cavernous
temporal vv.
sinus
Superior
and
inferior
petrosal
sinuses
Angular v.
Sigmoid
sinus
Deep
facial v.
Superficial
temporal v.
Pterygoid plexus
Maxillary v.
Retromandibular v.
41 Neurovasculature of the Skull & Face
Superior
ophthalmic v.
Left lateral view. Removed: Upper
ramus, condylar and coronoid processes of mandible. The pterygoid
plexus is a venous network situated
between the mandibular ramus and
the muscles of mastication. The cavernous sinus connects branches of
the facial vein to the sigmoid sinuses.
Retromandibular v.
posterior division
Internal
jugular v.
Retromandibular v.
anterior division
Facial v.
External
palatine v.
Parietal
emissary v.
Superior
sagittal sinus
Fig. 41.11 Veins of the occiput
Confluence
of the sinuses
Occipital
emissary v.
Posterior view. The superficial veins of the
occiput communicate with the dural venous
sinuses via emissary veins that drain to diploic
veins (calvaria, p. 545). Note: The external
vertebral venous plexus traverses the entire
length of the spine (p. 45).
Transverse
sinus
External occipital
protruberance
Sigmoid
sinus
Venous plexus
around foramen
magnum
Mastoid
emissary v.
Condylar
emissary v.
Internal
jugular v.
Occipital v.
External vertebral
venous plexus
Table 41.5
Venous anastomoses
The extensive venous anastomoses in this region provide routes for the spread of infections.
Extracranial vein
Connecting vein
Venous sinus
Angular v.
Superior and inferior ophthalmic vv.
Vv. of palatine tonsil
Pterygoid plexus; inferior ophthalmic v.
Superficial temporal v.
Parietal emissary vv.
Superior sagittal sinus
Occipital v.
Occipital emissary v.
Transverse sinus, confluence of the sinuses
Posterior auricular v.
Mastoid emissary v.
External vertebral venous plexus
Condylar emissary v.
Cavernous sinus*
Sigmoid sinus
*Deep spread of bacterial infection from the facial region may result in cavernous sinus thrombosis.
589
Head & Neck
Meninges
The brain and spinal cord are covered by membranes called meninges.
The meninges are composed of three layers: dura mater (dura), arachnoid mater (arachnoid membrane), and pia mater. The subarachnoid
space, located between the arachnoid mater and pia mater, contains
cerebrospinal fluid (CSF, see p. 684). See p. 40 for the coverings of the
spinal cord.
Diploic vv.
Fig. 41.12 Layers of the meninges
See pp. 686–687 for the veins of the brain.
Epidural hematoma
Cranial bone
Dura mater
(cut)
Cranial
bone
Neurothelium
Dura mater
Arachnoid
Outer
table
Subdural
hemorrhage
Arachnoid
trabeculae
Diploë
Inner
table
Cerebral cortex
Pia mater
Superior
sagittal sinus
Superior
cerebral vv.
Arachnoid
mater
Cerebral a.
Subarachnoid
space
Cerebral v.
A
Coronal section through the
meninges, anterior view.
Middle
cerebral a.
(branches)
Lateral lacuna
(opened)
Pia mater
(on cerebral
surface)
Arachnoid
granulations
(arachnoid villi)
Bridging vv.
Confluence of
the sinuses
Superior view of opened cranium. Left side: Dura mater (outer layer)
B
cut to reveal arachnoid (middle layer). Right side: Dura mater and
arachnoid removed to reveal pia mater (inner layer) lining the surface
of the brain. Note: Arachnoid granulations, sites for reabsorption of
cerebrospinal fluid into the venous blood, are protrusions of the
arachnoid layer of the meninges into the venous sinus system.
Fig. 41.13 Dural folds (septa)
Left anterior oblique view. Two layers of meningeal dura
come together, after separating from the periosteal dura
during formation of a dural (venous) sinus, to form a dural
fold or septum. These include the falx cerebri (separating
right and left cerebral hemispheres); the tentorium cerebelli
(supporting the cerebrum to keep it from crushing the underlying cerebellum); the falx cerebelli (not shown, separating right and left cerebellar lobes under the tentorium); and
the diaphragma sellae (forming the roof over the hypophyseal fossa and invaginated by the hypophysis).
590
Ostia of
bridging vv.
Falx cerebri
Diaphragma
sellae
Crista galli
Optic n.
Internal
carotid a.
Tentorial notch
Tentorium
cerebelli
Clinical box 41.3
Bleeding between the bony calvarium and the soft tissue of the brain
(extracerebral hemorrhage) exerts pressure on the brain. A rise of intracranial
pressure may damage brain tissue both at the bleeding site and in more
Bridging v.
Ruptured
middle
meningeal a.
Subarachnoid
space
remote brain areas. Three types of intracranial hemorrhage are distinguished
based on the relationship to the dura mater. See pp. 688–689 for the arteries
and pp. 686–687 for the veins of the brain.
Superior
sagittal
sinus
Falx cerebri
Dura mater
Inferior
sagittal
sinus
Calvaria
Ruptured
aneurysm
Sphenoid
sinus
A
Epidural hematoma (above the dura).
B
Subdural hematoma (below the dura).
C
Subarachnoid hemorrhage.
41 Neurovasculature of the Skull & Face
Extracerebral hemorrhages
Fig. 41.14 Arteries of the dura mater
Midsagittal section, left lateral view. See
pp. 688–689 for the arteries of the brain.
Middle meningeal a.
(frontal br.)
Middle meningeal a.
(parietal br.)
Fig. 41.15 Innervation of the dura mater
Superior view. Removed: Tentorium cerebelli
(right side).
Occipital a.
(mastoid br.)
Middle meningeal a.
Vertebral a.
(via foramen spinosum)
(brs.)
Cribriform plate
Anterior and
posterior
ethmoidal nn.
(meningeal brs.)
CN V1, V2,
and V3
(meningeal brs.)
CN V3
(meningeal br.)
Ist and 2nd
cervical nn.
(meningeal brs.)
CN X
(meningeal brs.)
CN V1 and V2
(tentorial brs.)
Tentorium
cerebelli
591
Head & Neck
Dural Sinuses
The dura mater is composed of two layers that separate in the region
of a venous sinus into an outer periosteal layer, which lines the calvaria
and an inner meningeal layer, which forms the unattached boundaries
of the sinus. In the region of a sinus, the two meningeal dural layers
come together after forming the sinus to create a dural fold, or septa
(see Fig. 41.13, p. 590). The network of venous sinuses collect blood
from the scalp, the calvaria, and the brain and eventually drain into the
internal jugular vein at the jugular foramen.
Fig. 41.16 Formation of a dural sinus
Superior sagittal sinus
Dura mater
Periosteal layer
Meningeal layer
Dura mater
Outer
table
Cranial
bone Diploë
Inner
table
Galea
aponeurotica
Emissary v.
Scalp vv.
Scalp
Lateral lacuna
(closed)
Granular
foveola
Outer table
Pia mater (on
cerebral surface)
Superior
cerebral vv.
Superior
sagittal sinus
Diploë
Inner table
Middle
cerebral a.
(brs.)
Lateral lacuna
(open)
Lateral
lacuna with
arachnoid
granulations
Falx
cerebri
Bridging v.
Arachnoid
granulations
(arachnoid
villi)
Superior
cerebral vv.
Bridging vv.
A
Structure of a dural sinus. Superior sagittal sinus, coronal section,
anterior view.
Ö
Falx
cerebri
K
D
Y
Ä
F
H
Table 41.6
Tentorium
cerebelli
G
Fig. 41.17 Dural sinuses
in the cranial cavity
Superior view of opened cranial
cavity. Dural sinus system ghosted
in blue. Removed: Tentorium
cerebelli (right side).
Lower group
Sphenoparietal
sinus
Anterior
sinus
Cavernous
sinus
Venous plexus of
foramen ovale
⑨
Superior sagittal
sinus
⑦
Cavernous sinus
Basilar plexus
②
Inferior sagittal
sinus
⑧
Anterior intercavernous sinus
⑫ petrosal sinus
③
Straight sinus
⑨
Posterior intercavernous sinus
④
Confluence of
the sinuses
⑩
Sphenoparietal
sinus
⑤
Transverse sinus
⑪
Superior petrosal
sinus
⑥
Sigmoid sinus
⑫
Inferior petrosal
sinus
⑩
⑦
Petrosquamous
sinus
Middle
meningeal v.
Superior petrosal
sinus
Jugular
foramen
Posterior
intercavernous
sinus
①
The occipital sinus is also included in the upper
group (see Fig. 49.1, p. 686).
Superior
ophthalmic v.
⑧ intercavernous
Principal dural sinuses
Upper group
592
B
Superior sagittal sinus in situ. Superior view of opened cranial cavity.
The roof of the sinus (the periosteal layer of the dura attached to the
calvaria) is removed. Left side: Areas of dura mater removed to show
arachnoid granulations (protrusions of the arachnoid layer of the
meninges) in the sinus. Right side: Dura mater and arachnoid layers
removed to reveal pia mater adhering to the cerebral cortex.
S
A
J
L
Confluence of
the sinuses
Inferior
Sigmoid ⑥
sinus
Great
cerebral v.
Marginal sinus
Inferior
cerebral vv.
Occipital
sinus
Transverse
sinus
Tentorium
cerebelli
③ Straight sinus
Confluence of the sinuses ④
Superior sagittal sinus
①
⑤
⑪
Fig. 41.18 Cavernous sinus
and cranial nerves
Internal carotid a.
Optic chiasm (optic n., CN II)
Oculomotor n. (CN III)
A
Superior view of the right
anterior and middle cranial
fossae. Removed: Lateral dural
wall and roof of the cavernous sinus. The trigeminal
ganglion is cut and retracted
laterally following removal of
its dural covering
Trochlear n. (CN IV)
Internal carotid a.
Cavernous sinus
Abducent n.
(CN VI)
Motor root
Sensory root
Middle
cranial fossa
Trigeminal nerve (CN V)
Anterior clinoid
process
B
Topography of the extradural course of the abducent
nerve along the clivus and in the left cavernous sinus.
Left lateral view. Note the long extradural path the
abducent nerve follows along the clivus. It runs within
the subarachnoid space, pierces the dura mater,
passes under Gruber’s ligament through Dorello’s
canal and enters the cavernous sinus at the tip of the
petrous temporal bone (at the junction of the middle
and posterior cranial fossae). It courses through the
cavernous sinus lateral to the internal carotid artery
to reach the orbit through the superior orbital fissure.
Trigeminal
ganglion
Posterior clinoid
process
Hypophyseal
fossa
Clivus
Dorello's canal
Ophthalamic a.
Internal carotid a.
Carotid siphon
Ophthalmic n.
(CN V1)
Trochlear n.
(CN IV)
Gruber's lig.
Oculomotor n.
(CN III)
Abducent n.
(CN VI)
Maxillary n.
(CN V2)
Trigeminal n.
(CN V)
Trigeminal
ganglion
Fig. 41.19 Cavernous sinus, coronal section through
middle cranial fossa
Anterior view. The right and left cavernous sinuses connect via the
intercavernous sinuses that pass around the hypophysis, which sits in the
hypophyseal fossa after invaginating the diaphragma sellae. On each side,
this coronal section cuts through the internal carotid artery twice due to
Optic n.
Hypophysis
41 Neurovasculature of the Skull & Face
Ophthalmic a.
the presence of the carotid siphon, a 180 degree bend in the cavernous
part of the artery. Of the five cranial nerves, or their divisions, associated
with the sinus only the abducent nerve (CN VI) is not embedded in the
lateral dural wall.
Internal carotid a.
Oculomotor n. (CN III)
Trochlear n. (CN IV)
Abducent n. (CN VI)
Ophthalmic n. (CN V1)
Cavernous sinus
Sphenoid
sinus
Maxillary n. (CN V2)
593
Head & Neck
Topography of the Superficial Face
Fig. 41.20 Superficial neurovasculature of the face
Anterior view. Removed: Skin and fatty subcutaneous tissue; muscles of
facial expression (left side).
Supratrochlear n.
Supraorbital n.,
medial and
lateral brs.
Superficial
temporal a. and v.,
auriculotemporal n.
Dorsal nasal a.
Facial n.,
temporal brs.
Auriculotemporal n.
Angular
a. and v.
Superficial temporal
a. and v.
Infraorbital a. and n.
(in infraorbital
foramen)
Transverse
facial a.
Facial n.,
zygomatic brs.
Facial n.,
buccal brs.
Zygomaticus major
Parotid gland
Parotid duct
Superior labial a.
Facial n.,
marginal mandibular br.
Facial a. and v.
Inferior labial a.
594
Masseter
Inferior alveolar a.,
mental br.
Mental n.
(in mental foramen)
Fig. 41.21 Superficial neurovasculature of the head
Left lateral view.
Superficial temporal
a. and v.
41 Neurovasculature of the Skull & Face
Superficial temporal
a., frontal br.
Superficial temporal
a., parietal br.
Supraorbital n.
(CN V1)
Supratrochlear n.
(CN V1)
Zygomaticoorbital a.
Auriculotemporal
n. (CN V3)
Infratrochlear
n. (CN V1)
Angular v.
External nasal
n. (CN V1)
Transverse
facial a.
Infraorbital n.
(CN V2)
Occipital a.
Parotid duct
Greater occipital
n. (C2, posterior
ramus)
Buccinator
Lesser occipital
n. (from cervical
plexus [C2])
Sternocleidomastoid
Mental n.
(CN V3)
Posterior auricular v.
Parotid gland
Facial v.
Masseter
Brs. of parotid
plexus of facial n.
Retromandibular
v., posterior
division
External
jugular v.
Great auricular
n. (from cervical
plexus [C2–C3])
595
Head & Neck
Topography of the Parotid Region & Temporal Fossa
Fig. 41.22 Parotid region
Left lateral view. Removed: Parotid gland,
sternocleidomastoid, and veins of the head.
Revealed: Parotid bed and carotid triangle.
Superficial temporal a.,
frontal and parietal brs.
Superior
(temporofacial)
trunk
Supraorbital n.
(CN V1)
Supratrochlear n.
(CN V1)
Auriculotemporal
n. (CN V3)
Infratrochlear
n. (CN V1)
Temporal brs.
of parotid
plexus (CN VII)
External nasal
n. (CN V1)
Infraorbital
n. (CN V2)
Occipital a.
Greater
occipital n.
(posterior
ramus of C2)
Zygomatic brs.
of parotid
plexus (CN VII)
Posterior auricular
n. (CN VII)
Parotid duct
Buccal brs.
of parotid
plexus (CN VII)
Lesser occipital n.
(cervical plexus [C2])
Sternocleidomastoid
Mental n.
(CN V3)
N. to digastric,
posterior belly (CN VII)
N. to stylohyoid
(CN VII)
Masseter
Marginal
mandibular br.
of parotid plexus
(CN VII)
596
Inferior
Cervical
Intraparotid
(cervicofacial) plexus of the
br. of
trunk
parotid plexus
facial n.
(CN VII)
(CN VII)
External
jugular v.
Great auricular n.
(cervical plexus [C2–C3])
Fig. 41.23 Temporal fossa
Temporal fossa (shaded)
Superior temporal
line
Inferior temporal
line
Frontal bone,
zygomatic process
Zygomatic bone,
frontal process
Supramastoid
crest
Zygomatic bone
Zygomatic arch
(cut)
Infratemporal fossa
(deep to ramus of mandible)
41 Neurovasculature of the Skull & Face
Left lateral view. The temporal fossa is located on
the lateral aspect of the skull. It communicates
with the infratemporal fossa inferiorly (medial to
the zygomatic arch). The main component of the
fossa is the large temporalis muscle.
Coronoid process
(in temporal fossa)
Fig. 41.24 Temporal fossa
Left lateral view. Removed: Sternocleidomastoid and masseter. Revealed: Temporal fossa
and temporomandibular joint (p. 638).
Temporomandibular
joint capsule
Zygomatic
arch
Temporalis
Coronoid
process
Facial n.
Parotid
duct (cut)
Masseter
Hypoglossal n.
Superior
cervical ganglion
Submandibular
gland, superficial
part
597
Head & Neck
Topography of the Infratemporal Fossa
Fig. 41.25 Bony boundaries of
Infratemoral fossa
Inferior orbital
fissure
Sphenopalatine
foramen
Temporal bone,
zygomatic process
Oblique external view of base of the
skull.
Temporal bone,
squamous part
Mandibular fossa
Articular eminence
External acoustic meatus
Foramen spinosum
Foramen ovale
Infratemporal
surface of maxilla
Lateral pterygoid plate
Maxillary tuberosity
Medial pterygoid plate
Palatine bone,
pyramidal process
Occipital condyle
Pterygoid hamulus
Foramen magnum
Maxilla,
palatine
process
Palatine bar,
maxillary
process
Pterygomaxillary
fissure
Fig. 41.26 Infratemporal fossa: Superficial dissection
Left lateral view. Removed: Ramus of mandible. Note: The mylohyoid
nerve (see Fig. 45.15 and 45.17A) branches from the inferior alveolar
nerve just before the mandibular foramen.
Temporalis (cut)
Superficial temporal
a. and v.
Deep temporal nn.
Superior alveolar nn.
posterior superior
alveolar br. (CN V2)
Maxillary a.
Posterior superior
alveolar a.
Buccal n. and a.
Medial pterygoid,
superficial and
deep heads
Lingual n.
Mandibular canal
Facial a. and v.
Deep temporal aa.
Auriculotemporal n.
Lateral pterygoid,
superior and
inferior heads
Facial n. (CN VII)
Ramus of mandible
(cut)
Inferior alveolar n.
Sternocleidomastoid
Masseter (cut)
Retromandibular v.,
posterior division
598
Left lateral view. Removed: Lateral pterygoid muscle (both heads).
Revealed: Deep infratemporal fossa and mandibular nerve as it enters the
mandibular canal via the foramen ovale in the roof of the fossa.
Temporalis (cut)
Superficial temporal
a. and v.
Deep temporal n.
Lateral pterygoid
(cut)
Sphenopalatine a.
Mandibular n. (CN V3)
Posterior superior
alveolar a.
Middle meningeal a.
Buccal a. and n.
41 Neurovasculature of the Skull & Face
Fig. 41.27 Infratemporal fossa: Deep dissection
Auriculotemporal n.
Maxillary a.
Buccinator
Medial pterygoid,
superficial head
Lingual n.
Sphenomandibular lig.
Facial n.
Medial pterygoid,
deep head
Mylohyoid n.
Facial a. and v.
Inferior alveolar
a. and n.
Masseter
599
Head & Neck
Neurovasculature of the Infratemporal Fossa
Fig. 41.28 Mandibular nerve (CN V3)
in the infratemporal fossa
Mandibular
division (CN V3)
Meningeal br.
Masseteric n.
Deep
temporal nn.
Auriculotemporal n.
Lateral
pterygoid n.
Parotid brs.
Medial
pterygoid n.
Inferior
alveolar n.
Buccal n.
Mandibular division
(CN V3)
Lingual n.
N. of tensor tympani
(with muscle)
Foramen
ovale
N. of tensor
veli palatini
(with muscle)
Facial n.
Stylomastoid
foramen
A
Left lateral view.
Lesser petrosal n.
Auriculotemporal n.
Medial pterygoid n.
Communicating
br. to auriculotemporal n.
Otic ganglion
Chorda tympani
Lingual n.
Mylohyoid n.
Inferior
alveolar n.
Left medial view.
B
Table 41.7
Nerves of the infratemporal fossa
Nerve
Nerve Fibers
Distribution
Muscular Branches (CN V3)
Branchial motor
Muscles of mastication; mylohyoid; tensor tympani; tensor veli palatini,
anterior belly of digastric
Auriculotemzporal (CN V3)
General sensory
Auricle, temporal region, and temporomandibular joint
Visceral motor from glossopharyngeal n. (CN IX)
Parotid gland
Inferior alveolar (CN V3)
General sensory
Mandibular teeth; mental branch supplies skin of lower lip and chin
Lingual (CN V3)
General sensory
Anterior two thirds of tongue, floor of mouth
Buccal (CN V3)
General sensory
Skin and mucous membrane of cheek
Meningeal (CN V3)
General sensory
Dura of middle cranial fossa
Special sensory taste
Anterior two thirds of tongue
Visceral motor
Submandibular and sublingual glands via submandibular ganglion and
lingual n (CN V3)
Chorda tympani (CN VII)
600
Mylohyoid n.
41 Neurovasculature of the Skull & Face
Fig. 41.29 Arteries in the infratemporal
fossa
Left lateral view into area. The maxillary artery
passes either superficial or deep to the lateral
pterygoid in the infratemporal fossa (see Fig.
41.27, p. 599) and passes medially into the
pterygopalatine fossa through the pterygo­
maxillary fissure.
Pterygomaxillary fissure
⑬
Inferior orbital
fissure
⑧
⑥
⑪
⑩
⑦
Zygomatic
process (cut)
⑫
⑨
⑤
Pterygoid
process,
lateral plate
Lesser
palatine a.
④
③
②
①
Maxillary a.
Greater
palatine a.
Table 41.8
Branches of the maxillary artery
Part
Mandibular part (between
the origin and the first circle
around artery in Fig. 41.29)
Pterygoid part (between
the first and second circles
around the artery)
Artery
Distribution
① Inferior alveolar a.
Mandible, teeth, gingiva
② Anterior tympanic a.
Tympanic cavity
③ Deep auricular a.
Temporomandibular joint, external auditory canal
④ Middle meningeal a.
Calvaria, dura, anterior and middle cranial fossae
⑤ Masseteric a.
Masseter m.
⑥ Deep temporal aa.
Temporalis m.
⑦ Pterygoid brs.
Pterygoid mm.
⑧ Buccal a.
Buccal mucosa
⑨ Descending palatine a.
Pterygopalatine part
(between the second and
third circles around the
artery)
Greater palatine a.
Hard palate
Lesser palatine a.
Soft palate, palatine tonsil, pharyngeal wall
⑩ Posterior superior alveolar a.
Maxillary molars, maxillary sinus, gingiva
⑪ Infraorbital a.
Maxillary alveoli
⑫ A. of pterygoid canal
⑬ Sphenopalatine a.
Lateral posterior nasal aa.
Lateral wall of nasal cavity, choanae
Posterior septal brs.
Nasal septum
601
42
Orbit & Eye
Head & Neck
Bones of the Orbit
Fig. 42.1 Bones of the orbit
Frontal incisure
Supraorbital
foramen
Posterior
ethmoidal foramen
Frontal bone,
orbital surface
Anterior
ethmoidal foramen
Zygomaticoorbital foramen
Optic canal (sphenoid bone)
Nasal bone
Superior
orbital fissure
Maxilla,
frontal process
Zygomatic
bone
Inferior
orbital fissure
Lacrimal bone
Ethmoid bone,
orbital plate
Infraorbital
groove
A
Anterior view.
Maxilla, orbital surface
Infraorbital foramen
Frontal bone, orbital surface
Lacrimal bone
Maxilla,
frontal process
Anterior and posterior
ethmoidal foramina
Lacrimal bone,
posterior
lacrimal crest
Maxilla, anterior
lacrimal crest
Ethmoid bone
Sphenoid,
optic canal
Superior
orbital fissure
Fossa of
lacrimal sac
(with opening
for nasolacrimal
duct)
Foramen
rotundum
Maxilla,
orbital surface
Inferior
orbital fissure
Pterygopalatine
fossa
B
Lateral view of right orbit.
Table 42.1
Maxillary
hiatus
Maxillary
sinus
Infraorbital
foramen
Openings in the orbit for neurovascular structures
Opening*
Nerves
Optic canal
Optic n. (CN II)
Vessels
Ophthalmic a.
Trigeminal n., ophthalmic division (CN V1)
• Lacrimal n.
• Frontal n.
• Nasociliary n.
Superior orbital fissure
Oculomotor n. (CN III)
Trochlear n. (CN IV)
Abducent n. (CN VI)
Inferior orbital fissure
Infraorbital n. (CN V2)
Zygomatic n. (CN V2)
Infraorbital canal
Infraorbital n. (CN V2), a., and v.
Supraorbital foramen
Supraorbital n. (lateral br.)
Supraorbital a.
Frontal incisure
Supraorbital n. (medial br.)
Supratrochlear a.
Anterior ethmoidal foramen
Anterior ethmoidal n., a., and v.
Posterior ethmoidal foramen
Posterior ethmoidal n., a., and v.
* The nasolacrimal canal transmits the nasolacrimal duct.
602
Infraorbital
canal
Superior ophthalmic v.
Infraorbital a. and v., inferior ophthalmic v.
42 Orbit & Eye
Frontal bone,
orbital surface
Frontal
sinus
Superior
orbital fissure
Zygomatic bone,
orbital surface
Zygomaticoorbital foramen
Table 42.2
Direction
Bordering structure
Sphenoid bone,
lesser wing
Superior
Sphenoid bone,
greater wing
Medial
Ethmoid sinus
Inferior
Maxillary sinus
Maxilla,
orbital surface
Frontal sinus
Anterior cranial fossa
Certain deeper structures also have a clinically important relationship
to the orbit:
Infraorbital
canal
Inferior
orbital fissure
Structures surrounding the orbit
Maxillary
sinus
Sphenoid sinus
Hypophysis (pituitary)
Middle cranial fossa
Cavernous sinus
Optic chiasm
Pterygopalatine fossa
Palatine bone,
pyramidal
process
C
Medial view of right orbit.
Frontal
sinus
Ethmoid bone,
crista galli
Frontal bone,
orbital surface
Sphenoid bone,
lesser wing
Ethmoid bone,
perpendicular plate
Optic canal
Ethmoid bone,
orbital plate
(lamina papyracea)
Superior
orbital fissure
Ethmoid bone,
superior nasal concha
Sphenoid bone,
greater wing
Inferior
orbital fissure
Zygomatic bone,
orbital surface
Infraorbital
canal
Orbital floor
Ethmoid bone,
middle nasal concha
Inferior
nasal concha
Ethmoid
bone
Maxillary
sinus
Maxilla, palatine
process
Vomer
DCoronal section, anterior view.
603
Head & Neck
Muscles of the Orbit
Fig. 42.2 Extraocular muscles
The eyeball is moved by six extrinsic muscles: four rectus (superior,
inferior, medial, and lateral) and two oblique (superior and inferior).
Superior
rectus
Superior
oblique
Medial
rectus
Lateral
rectus
Inferior
oblique (origin)
Tendon
of superior
oblique
Inferior
rectus
Trochlea
Superior
rectus
Inferior
oblique
Superior
oblique
Inferior
rectus
A
Right eye, anterior view.
Inferior oblique
(insertion)
Medial
rectus
Common
tendinous
ring
Lateral
rectus
Levator
palpebrae
superioris
Optic n. (CN II,
in optic canal)
B
Right eye, superior view of opened orbit.
Depress
Elevate
Fig. 42.3 Testing the extraocular muscles
Inferior oblique
Lateral
rectus
Superior oblique
Abduct
Superior rectus
Inferior oblique
Medial
rectus
Inferior rectus
Inferior
oblique
Inferior
rectus
Superior
oblique
Lateral
rectus
Superior oblique
Adduct
A
Starting with the eyes directed anteriorly, movement to any of the cardinal directions of gaze (arrows) requires activation of two extraocular muscles, each of which
is innervated by a different cranial nerve, thus testing the function of those pairs of
muscles.
604
Superior
rectus
Abduct
Abduct
Adduct
B
Starting with the eyes adducted or
abducted, elevating or lowering the eyes
activates only the oblique or the rectus
muscles, respectively, allowing for testing
of the function of individual muscles.
42 Orbit & Eye
Fig. 42.4 Actions of the extraocular muscles
Superior view of opened orbit. Vertical axis, red circle;
horizontal axis, black; anteroposterior (visual/optical)
axis, blue.
A
Superior rectus.
Table 42.3
B
Medial rectus.
C
Inferior rectus.
DLateral rectus.
F
Inferior oblique.
E
Superior oblique.
Extraocular muscles
Action (see Fig. 42.4)*
Muscle
Origin
Insertion
Superior rectus
Medial rectus
Inferior rectus
Common tendinous
ring (common annular
tendon)
Lateral rectus
Sclera of
the eye
Vertical
axis (red)
Horizontal
axis (black)
Anteroposterior
axis (blue)
Innervation
Elevates
Adducts
Rotates medially
Oculomotor n. (CN III), superior branch
—
Adducts
—
Depresses
Adducts
Rotates laterally
Oculomotor n. (CN III), inferior branch
—
Abducts
—
Abducent n. (CN VI)
Superior oblique
Sphenoid bone+
Depresses
Abducts
Rotates medially
Trochlear n. (CN IV)
Inferior oblique
Medial orbital margin
Elevates
Abducts
Rotates laterally
Oculomotor n. (CN III), inferior branch
* Starting from gaze directed anteriorly
+
The tendon of the superior oblique passes through a tendinous loop (trochlea) attached to the superomedial orbital margin.
Clinical box 42.1
Oculomotor palsies
Oculomotor palsies may result from a lesion involving an eye muscle or its
associated cranial nerve (at the nucleus or along the course of the nerve). If
one extraocular muscle is weak or paralyzed, deviation of the eye will be noted.
A
Abducent nerve palsy. Disabled:
Lateral rectus.
Impairment of the coordinated actions of the extraocular muscles may cause
the visual axis of one eye to deviate from its normal position. The patient will
therefore perceive a double image (diplopia).
Superior
rectus
B
Trochlear nerve palsy. Disabled:
Superior oblique.
Lateral
rectus
23°
Visual (optical) axis
Orbital axes
C
Complete oculomotor palsy. Disabled: Superior, inferior, and medial recti
and inferior oblique.
DNormal visual and orbital axes.
605
Head & Neck
Neurovasculature of the Orbit
Superior
ophthalmic v.
Supratrochlear v.
Fig. 42.5 Veins of the orbit
Dorsal
nasal v.
Lateral view of the right orbit. Removed: Lateral
orbital wall. Opened: Maxillary sinus.
Lacrimal v.
Angular v.
Cavernous
sinus
Ophthalmic v.
Inferior
ophthalmic v.
Infraorbital v.
Facial v.
Clinical box 42.2
Cavernous sinus syndrome
Fig. 42.6 Arteries of the orbit
Superior view of the right orbit. Opened: Optic
canal and orbital roof.
Supratrochlear a.
Dorsal nasal a.
Supraorbital a.
Medial
palpebral a.
Long
posterior
ciliary aa.
Short
posterior
ciliary aa.
Lacrimal a.
Anterior
ethmoidal a.
Central
retinal a.
Posterior
ethmoidal a.
Gravity allows venous blood from the danger triangle region of the
face (see figure) to drain to the cavernous sinus via the valveless
ophthalmic veins. Squeezing a pimple or boil in this facial region
can result in infectious thrombi being forced into the venous
system and passing back into the cavernous sinus. Cavernous sinus
syndrome (CIS) is diagnosed by the loss of eyeball movement due
to the various cranial nerves associated with the cavernous sinus
becoming infected.
The abducent nerve (CN VI) is bathed in blood within the sinus,
the first ocular movement to be affected is lateral deviation
of the eyeball. The oculomotor (CN III) and trochlear (CN IV)
nerves, embedded in the dural lateral wall of the sinus are also
eventually affected as the infection penetrates the dura. The
eyeball becomes frozen in the orbit as all nerves activating the
extraocular mm. become infected. CN V1 is also in the lateral dural
wall so a tingling/parasthesia is felt in the sensory region covered
(forehead). Occasionally CN V2 may also be involved and this
parasthesia may also extend to the skin of the face below the orbit.
The intercavernous sinuses allow the infection to spread to the
cavernous sinus on the opposite side. If left untreated, death can
result however cavernous sinus septic thrombophlebitis mortality
has decreased from 100% to 20% with the of improvements in
diagnosis and treatment.
Optic n. (CN II)
Internal
carotid a. (in
cavernous sinus)
Danger
triangle
Ophthalmic a.
606
Middle
meningeal a.
(from maxillary a.)
Anastomotic br.
Fig. 42.7 Innervation of the orbit
Frontal n.
Lateral view of the right orbit. Removed:
Temporal bony wall.
Lacrimal n.
(with gland)
Oculomotor
n. (CN III)
Supraorbital n.
Internal carotid
a. with internal
carotid plexus
Supratrochlear n.
Long
ciliary nn.
Trochlear n.
(CN IV)
42 Orbit & Eye
Oculomotor n.,
superior br.
Nasociliary n.
Ophthalmic
division
(CN V1)
Short
ciliary nn.
Trigeminal
n. (CN V)
Ciliary
ganglion
Trigeminal
ganglion
Parasympathetic
root
Mandibular
division
(CN V3)
Abducent n.
(CN VI)
Maxillary division
(CN V2)
Optic n. (CN II)
Oculomotor n.,
inferior br.
Sympathetic
root
Nasociliary
(sensory) root
Fig. 42.8 A course of the cranial nerves through the cavernous sinus toward the orbit
Sella turcica with partially opened cavernous sinus on the right side,
cranial view.
The trigeminal ganglia are displayed on both sides. The right ganglion is
pulled laterally from its normal position (thereby exposing the trigeminal cave = Meckel’s cave) to show the cavernous sinus and the internal
carotid artery, which passes through the sinus.
Note the abducent nerve also traverses the cavernous sinus and runs
lateral to the carotid artery. All other nerves (oculomotor, trochlear and
the three branches of the trigeminal) run rostrally and caudally in the
Optic n.
(CN I)
lateral dural wall of the cavernous sinus. Most cases of intracavernous
carotid aneurysm only involve the abducent nerve. The space-occupying
aneurysm compresses the nerve, causing a loss of function. In cases
with sudden onset of isolated abducent nerve palsy, carotid aneurysm
should always be considered as a possible cause. In contrast, isolated
trochlear nerve palsy is rare. More often, the trochlear nerve is one of
multiple nerves affected, e.g. in cases of cavernous sinus thrombosis
which involves all nerves traveling through the cavernous sinus, often
affecting also both branches of the trigeminal nerve.
Internal
carotid a.
Oculomotor n.
(CN III)
Opthalmic n. (CN V1)
Trochlear n.
(CN IV)
Trochlear n. (CN IV)
Trigeminal n.
(minor portion)
Maxillary n. (CN V2)
Oculomotor n. (CN V1)
Trigeminal n.
(major portion)
Mandibular n. (CN V3)
Trigeminal ganglion
Trigeminal cave
Cavernous
sinus
Trigeminal n.
(CN V)
Clivus
Abducent n.
(CN VI)
Facial n.
(CN VII)
607
Head & Neck
Topography of the Orbit
Fig. 42.9 Neurovascular structures of the orbit
Anterior view. Right side: Orbicularis oculi removed. Left side: Orbital
septum partially removed.
Medial palpebral
lig.
Supraorbital
a. and n.
Superior ophthalmic
Infraa. and v.
trochlear n.
Supratrochlear n.
Levator palpebrae
superioris
Superior
tarsal m.
Lacrimal gland,
orbital part
Lacrimal
gland,
palpebral
part
Orbital
septum
Lateral
palpebral
lig.
Superior
and
inferior
tarsus
Facial
a. and v.
Angular
a. and v.
Dorsal nasal
a. and v.
Lacrimal
sac
Infraorbital
a. and n.
Fig. 42.10 Passage of neurovascular structures through
the orbit
Anterior view. Removed: Orbital contents. Note: The optic nerve and
ophthalmic artery travel in the optic canal. The remaining structures
pass through the superior orbital fissure.
Lacrimal n.
Frontal n.
Trochlear n.
(CN IV)
Levator palpebrae
superioris
Superior
rectus
Superior
oblique
Superior
ophthalmic v.
Optic n. (CN II, in optic canal)
Superior
orbital fissure
Common
tendinous ring
Oculomotor n. (CN III),
superior br.
Ophthalmic a.
Nasociliary n.
Medial rectus
Lateral rectus
Inferior orbital
fissure
Oculomotor n. (CN III),
inferior br.
Abducent n.
(CN VI)
608
Inferior
ophthalmic v.
Inferior
rectus
Fig. 42.11 Neurovascular contents of the orbit
Superior
ophthalmic v.
Supraorbital
aa. and nn.
42 Orbit & Eye
Superior view. Removed: Bony roof of orbit, peritorbita, and
retro-orbital fat.
Infratrochlear n.
Cribriform plate
Anterior ethmoidal
a. and n.
Supratrochlear
a. and n.
Posterior ethmoidal
a. and n.
Levator palpebrae
superioris
Lacrimal a. and n. (with gland)
Lateral rectus
Supraorbital a.
Nasociliary n.
Trochlear n.
(CN IV)
Superior rectus
Abducent n. (CN VI)
Inferior
ophthalmic v.
Frontal n.
A
Upper level.
Medial
rectus
Superior
oblique
Levator palpebrae
superioris
Superior rectus
Superior
ophthalmic v.
Lacrimal gland
Nasociliary n.
Lacrimal a. and n.
Long ciliary nn.
Trochlear n. (CN IV)
Short posterior ciliary aa.,
short ciliary nn.
Optic n. (CN II)
Nasociliary n.
Lateral rectus
Inferior
ophthalmic v.
Abducent n. (CN VI)
Ciliary ganglion
Oculomotor n. (CN III)
B
Middle level. Reflected: Levator palpebrae
superioris and superior rectus. Revealed:
Optic nerve.
609
Head & Neck
Orbit & Eyelid
Fig. 42.12 Topography of the orbit
Sagittal section through the right orbit, medial view.
Episcleral
space
Orbital roof
Bulbar fascia
(Tenon’s capsule)
Periorbita
Levator palpebrae
superioris
Adipose tissue
of the orbit
Superior rectus
Orbital septum
Eyeball
Optic n.
(with dural sheath)
Inferior rectus
Orbital septum
Inferior oblique
Sclera
Infraorbital n.
Orbital floor
Maxillary sinus
Fig. 42.13 Eyelids and conjuctiva
Sagittal section through the anterior orbital cavity.
Orbital roof
Periorbita
Levator palpebrae
superioris
Orbital
septum
Superior rectus
Superior
conjunctival fornix
Orbicularis
oculi,
orbital part
Superior tarsal m.
Superior tarsus
(with tarsal glands)
Lens
Upper
eyelid
Cornea
Iris
Ciliary body
Inferior tarsus
Ciliary and
sebaceous glands
Retina
Sclera
Lower
eyelid
Inferior tarsal m.
Orbicularis oculi,
palpebral part
Infraorbital n.
610
Fig. 42.14 Lacrimal apparatus
Right eye, anterior view. Removed: Orbital septum (partial). Divided:
Levator palpebrae superioris (tendon of insertion).
42 Orbit & Eye
Levator palpebrae
superioris
Orbital
septum
Lacrimal
caruncle
Lacrimal gland,
orbital part
Superior and
inferior lacrimal
canaliculi
Lacrimal gland,
palpebral part
Medial palpebral
lig.
Upper eyelid
Lacrimal sac
Superior and
inferior puncta
Lower eyelid
Nasolacrimal
duct
Infraorbital
foramen
Inferior
nasal concha
Clinical box 42.3
Lacrimal drainage
Perimenopausal women are frequently subject to chronically dry eyes
(keratoconjunctivitis sicca), due to insufficient tear production by the
lacrimal gland. Acute inflammation of the lacrimal gland (due to bacteria)
is less common and characterized by intense inflammation and extreme
tenderness to palpation. The upper eyelid shows a characteristic S-curve.
611
Head & Neck
Eyeball
Fig. 42.15 Structure of the eyeball
Transverse section through right eyeball, superior view. Note: The
orbital axis (running along the optic nerve through the optic disk)
­deviates from the optical axis (running through the center of the eye
to the fovea centralis) by 23 degrees.
Optical
axis
Orbital
axis
Posterior
chamber
23°
Iris
Lens
Cornea
Anterior
chamber
Chamber angle
Scleral venous sinus
(canal of Schlemm)
Corneoscleral limbus
Pigment epithelium
of the ciliary body
Ciliary body,
ciliary m.
Ocular
conjunctiva
Zonular fibers
Ora serrata
Hyaloid
fossa
Vitreous
body
Medial
rectus
Lateral
rectus
Retina
Choroid
Optic disk
Sclera
Macula lutea
Lamina cribrosa
Central
retinal a.
Fovea centralis
Optic n. (CN II)
612
Fig. 42.16 Blood vessels of the eyeball
Lesser arterial circle of iris
Transverse section through the right eyeball
at the level of the optic nerve, superior view.
The arteries of the eye arise from the ophthalmic artery, a terminal branch of the internal
carotid artery. Blood is drained by four to eight
vorticose veins that open into the superior and
inferior ophthalmic veins.
42 Orbit & Eye
Scleral venous sinus
(canal of Schlemm)
Anterior
conjunctival a.
Greater
arterial circle
of iris
Anterior
ciliary aa.
Arterial circle
of Zinn
(and von Haller)
Short posterior
ciliary aa.
Pial vascular
plexus
Long
posterior
ciliary aa.
Vorticose v.
Choroid (choroidocapillary layer)
Central retinal a. and v.
Optic n. (CN II)
Clinical box 42.4
Optic fundus
The optic fundus is the only place in the body where capillaries can be examined directly. Examination
of the optic fundus permits observation of vascular changes that may be caused by high blood pressure
or diabetes. Examination of the optic disk is important in determining intracranial pressure and
diagnosing multiple sclerosis.
Nasal
Macula lutea
Optic disk
Central
retinal a.
Central
retinal v.
Temporal
Fovea
centralis
Physiological cup
B
Normal optic fundus in the ophthalmoscopic
examination.
Optic disk
(blind spot)
Central retinal
a. and v.
(sites of
entry and
emergence)
Macula lutea
(yellow spot)
A
Retina of left eyeball,
anterior view, schematic.
C
High intracranial pressure; the edges of the
optic disk appear less sharp.
613
Head & Neck
Cornea, Iris & Lens
Fig. 42.17 Cornea, iris, and lens
Transverse section through the
anterior segment of the eye.
Anterosuperior view.
Anterior chamber
Cornea
Iris
Pupillary
sphincter
Chamber
angle
Pupillary
dilator Scleral venous
sinus (canal
of Schlemm)
Ocular
conjunctiva
Ciliary m.
Ciliary body
Posterior chamber
Fig. 42.18 Iris
Pupil
Cornea
Transverse section through the anterior
segment of the eye. Anterosuperior
view.
Lens
Zonular
fibers
Sclera
Pupillary
sphincter
Pupillary
dilator
Lesser
arterial
circle of iris
Iris stroma
Greater
arterial
circle of iris
Pigmented iris
epithelium
(two layers)
Clinical box 42.5
Glaucoma
Aqueous humor produced in the posterior chamber passes through the
pupil into the anterior chamber. It seeps through the spaces of the trabecular
meshwork into the scleral venous sinus (canal of Schlemm) before passing
into the episcleral veins. Obstruction of aqueous humor drainage causes an
increase in intraocular pressure (glaucoma), which constricts the optic nerve
Trabecular meshwork
Cornea
in the lamina cribrosa. This constriction eventually leads to blindness. The
most common glaucoma (approximately 90% of cases) is chronic (openangle) glaucoma. The more rare acute glaucoma is characterized by red eye,
strong headache and/or eye pain, nausea, dilated episcleral veins, and edema
of the cornea.
Anterior
chamber
Scleral venous sinus
(canal of Schlemm)
Conjunctiva
Episcleral vv.
B
Chronic (open-angle)
glaucoma. Drainage through
the trabecular meshwork is
impaired.
Sclera
A
Normal drainage.
614
Ciliary
body
Chamber
angle
Posterior
chamber
Iris
C
Acute (angle-closure) glaucoma. The chamber angle is
obstructed by iris tissue. Aqueous fluid cannot drain into the
anterior chamber, which pushes
portions of the iris upward,
blocking the chamber angle.
Fig. 42.19 Pupil
42 Orbit & Eye
Pupil size is regulated by two intraocular
muscles of the iris: the pupillary sphincter,
which narrows the pupil (parasympathetic
innervation), and the pupillary dilator, which
enlarges it (sympathetic innervation).
A
Normal pupil size.
B
Maximum constriction
(miosis).
C
Maximum dilation
(mydriasis).
Fig. 42.20 Lens and ciliary body
Posterior view. The curvature of the lens
is regulated by the muscle fibers of
the annular ciliary body.
Lens
Iris
Ciliary body,
pars plicata
Ciliary body,
pars plana
Sclera
Choroid
Retina,
optical part
Zonular
fibers
Ciliary processes
Fig. 42.21 Light refraction by the lens
Transverse section, superior view. In the normal (emmetropic) eye, light
rays are refracted by the lens (and cornea) to a focal point on the retinal
surface (fovea centralis). Tensing of the zonular fibers, with ciliary
muscle relaxation, flattens the lens in response to parallel rays arriving
Ciliary m.
from a distant source (far vision). Contraction of the ciliary muscle, with
zonular fiber relaxation, causes the lens to assume a more rounded
shape (near vision).
Nearsightedness
(myopia)
Retina
Fovea centralis
Lens
Ora serrata
Normal
vision
Farsightedness
(hyperopia)
Incident
light rays
Far
vision
Incident
light rays
Fovea centralis
Near
vision
Lens
A
Normal dynamics of the lens.
B
Abnormal lens dynamics.
615
43 Nasal Cavity & Nose
Head & Neck
Bones of the Nasal Cavity
Fig. 43.1 Skeleton of the nose
The skeleton of the nose is composed of an upper bony portion and a
lower cartilaginous portion. The proximal portions of the nostrils (alae)
are composed of connective tissue with small embedded pieces of
cartilage.
Major alar cartilage
Nasion
Lateral crus
Nasal bone
Medial crus
Frontal process
of maxilla
Lateral
nasal
cartilage
Naris
Nasal
ala
Major alar
cartilage
Septal
cartilage
Anterior
nasal spine
Minor alar
cartilages
A
Left lateral view.
B
Inferior view.
Fig. 43.2 Bones of the nasal cavity
The left and right nasal cavities are flanked by lateral walls and
separated by the nasal septum. Air enters the nasal cavity through
the anterior nasal aperture and travels through three passages: the
superior, middle, and inferior meatuses (arrows). These passages are
separated by the superior, middle, and inferior conchae. Air leaves the
nose through the choanae, entering the nasopharynx.
Anterior
cranial fossa
Cribriform
plate
Frontal bone
Crista galli
Sphenoid
sinus
Frontal sinus
Nasal bone
Hypophyseal
fossa
Ethmoid bone,
perpendicular
plate
Sphenoid
crest
Vomer
Septal
cartilage
Choana
Major alar
cartilage,
medial crus
Posterior process
Palatine bone,
horizontal plate
Nasal crest
Incisive canal
Oral cavity
Maxilla,
palatine process
Left side of nasal septum in left nasal cavity. Parasagittal section.
A
616
Anterior
Sphenoethmoidal
cranial fossa
recess
Superior
meatus
Middle cranial
fossa
Frontal sinus
Sphenoid bone,
lesser wing
Hypophyseal fossa
Lacrimal bone
Sphenoid sinus
Maxilla, frontal
process
Superior concha
(ethmoid bone)
Anterior nasal
aperture
Medial plate
Choana
Lateral plate
43 Nasal Cavity & Nose
Crista galli
Pterygoid
process
Middle meatus
Inferior
concha
Palatine bone,
horizontal plate
Maxilla, palatine process
Inferior
meatus
Middle concha
(ethmoid bone)
B
Right lateral wall of the right nasal cavity. Sagittal section, medial
view. Removed: Nasal septum. Note: The superior and middle conchae
are parts of the ethmoid bone, whereas the inferior nasal conchae is
a separate bone.
Cribriform
plate
Orifices of posterior
ethmoid sinus
Superior
concha (cut)
Sphenoid sinus
Sphenopalatine
foramen
Ethmoid bulla
Lacrimal bone
Uncinate
process
Inferior
concha (cut)
Maxilla, palatine
process
Middle concha (cut)
Maxillary
hiatus
Palatine bone,
perpendicular plate
Inferior meatus
C
Right lateral wall of the right nasal cavity with the conchae removed.
Sagittal section, medial view. Revealed: Paranasal sinuses (p. 618).
617
Head & Neck
Paranasal Air Sinuses
Fig. 43.3 Location of the paranasal sinuses
The paranasal sinuses (frontal, ethmoid, maxillary, and sphenoid) are
air-filled cavities that reduce the weight of the skull.
Age 20
Age 12
Frontal
sinus
Age 8
Age 1
Age 4
Age 4
Ethmoid
sinus
Age 1
Age 8
Age 12
Age 20
Maxillary
sinus
Age 60+
Sphenoid
sinus
A
Anterior view.
C
Pneumatization (the formation of air-filled cells and cavities) of the
sinuses with age. The frontal (yellow) and maxillary (orange) sinuses
develop gradually over the course of cranial growth.
B
Left lateral view.
Fig. 43.4 Paranasal sinuses
Superior concha
Arrows indicate the flow of mucosal secretions from the sinuses and the
nasolacrimal duct into the nasal cavity (see Table 43.1).
Ethmoid
bulla
Middle
concha
(cut)
Sphenoethmoidal
recess
Hiatus
semilunaris
Frontal
sinus
Superior
meatus
Superior
concha
(cut)
Middle
meatus
Orbit
Nasal
cavity
Ethmoid
sinus
Middle
concha
Nasal
septum
Maxillary
sinus
Inferior concha (cut)
Inferior
concha
Inferior meatus
Openings of the paranasal sinuses and nasolacrimal duct. Sagittal
A
section, medial view of the right nasal cavity.
Table 43.1
Nasal passages into which sinuses empty
Sinuses/duct
Nasal passage
Via
Sphenoid sinus (blue)
Sphenoethmoidal recess
Direct
Posterior cells
Superior meatus
Direct
Anterior and middle cells
Middle meatus
Ethmoid bulla
Frontal sinus (yellow)
Middle meatus
Frontonasal duct into hiatus semilunaris
Maxillary sinus (orange)
Middle meatus
Hiatus semilunaris
Nasolacrimal duct (red)
Inferior meatus
Direct
Ethmoid sinus (green)
618
Paranasal sinuses and osteomeatal unit in the left nasal cavity. CoroB
nal section, anterior view.
Fig. 43.5 Bony structure of the paranasal sinuses
Coronal section, anterior view.
Ethmoid
bone
43 Nasal Cavity & Nose
Frontal
sinus
Anterior
cranial fossa
Parietal bone
Frontal bone
Sphenoid bone,
lesser wing
Temporal bone
Ethmoid
sinus
Sphenoid bone,
greater wing
Superior orbital
fissure
(to middle
cranial fossa)
Zygomatic
bone
Maxillary
sinus
Inferior
concha
Vomer
A
Bones of the paranasal sinuses.
Cribriform
plate
Crista
galli
Frontal
sinus
Perpendicular
plate
Superior
meatus
Orbital plate
Superior
concha
Orbit
Middle
meatus
Middle
ethmoid sinus
Ostium of
maxillary sinus
Middle
concha
Uncinate process
Maxillary
sinus
Inferior
meatus
Inferior
concha
Vomer
Palatine
process
of maxilla
B
Ethmoid bone (red) in the paranasal sinuses.
Ethmoid
sinuses
Deviated
septum
Maxillary
sinus
Inferior
conchae
Clinical box 43.1
Deviated septum
The normal position of the nasal septum creates two roughly symmetrical
nasal cavities. Extreme lateral deviation of the septum may result in
obstruction of the nasal passages. This may be corrected by removing
portions of the cartilage (septoplasty).
Sinusitis
C
MRI through the paranasal sinuses.
When the mucosa in the ethmoid sinuses becomes swollen due to
inflammation (sinusitis), it blocks the flow of secretions from the frontal
and maxillary sinuses in the osteomeatal unit (see Fig. 43.4). This
may cause microorganisms to become trapped, causing secondary
inflammations. In patients with chronic sinusitis, the narrow sites can be
surgically widened to establish more effective drainage routes.
619
Head & Neck
Neurovasculature of the Nasal Cavity
Fig. 43.6 Nasal septum
and lateral wall
Anterior
ethmoidal a.
Olfactory
bulb (CN I)
Sphenoid
sinus
Hypophyseal
fossa
Frontal sinus
Olfactory fibers (CN I)
Medial superior
posterior nasal
brs. (CN V2)
Anterior septal brs.
(from anterior ethmoidal a.)
Posterior septal
brs. (from sphenopalatine a.)
Medial nasal br.
Choana
Torus tubarius
Pharyngeal orifice of
pharyngotympanic
(auditory) tube
Nasopalatine n.
Axis (C2)
A
Nerves and arteries of the left side of the
nasal septum.
Sphenoid sinus
Cribriform plate
Sphenoethmoid
recess
Superior
concha
Superior
meatus
Middle
concha
Middle
meatus
Pharyngeal
tonsil
Inferior
concha
Salpingopharyngeal
fold
Limen nasi
B
Mucosa of the right lateral nasal wall.
Sagittal section.
Inferior
meatus
Nasal vestibule
Uvula
Fig. 43.7 Arteries of the nasal cavity
Note: The venous drainage of the nasal cavity is
into the a­ nterior facial and ophthalmic veins.
Posterior
ethmoidal a.
Posterior
ethmoidal a.
Ophthalmic a.
Ophthalmic a.
Anterior
ethmoidal a.
Sphenopalatine a.
Sphenopalatine a.
Descending
palatine a.
Maxillary a.
Anterior
septal brs.
Internal
carotid a.
Kiesselbach’s
area
Posterior
septal brs.
A
Arteries of the left side of the nasal septum.
620
Anterior
ethmoidal a.
External
carotid a.
Lateral posterior
nasal aa.
Greater palatine a.
B
Arteries of the right lateral nasal wall.
Superior
concha
Sphenoethmoidal
recess
Fig. 43.8 Lateral nasal wall
Sphenoid
sinus
43 Nasal Cavity & Nose
Frontal sinus
Ethmoid bulla
Middle concha (cut)
Opening of
frontonasal duct
Inferior concha (cut)
Semilunar hiatus
Pharyngeal orifice of
pharyngotympanic
(auditory) tube
Opening of
nasolacrimal duct
Inferior
meatus
Maxillary n. (V2)
Olfactory bulb (CN I)
Pterygopalatine ganglion
A
Lateral nasal wall with middle and
inferior conchae removed to show
anatomy of underlying meatuses.
Trigeminal (CN V)
ganglion
Internal carotid a.
Internal
carotid
plexus
Olfactory fibers,
posterior ethmoidal a.
Anterior
ethmoidal a.
Greater
petrosal n.
Inferior posterior
nasal br., lateral
posterior nasal aa.
Deep
petrosal n.
N. of the
pterygoid
canal
Clinical box 43.2
Nosebleeds
Vascular supply to the nasal cavity arises
from both the internal and external carotid
arteries. The anterior part of the nasal
septum contains a very vascularized region
referred to as Kiesselbach’s area. This area
is the most common site of significant
nosebleeds.
Lesser palatine a. and n.
Greater palatine n. and a.
B
Nerves and arteries of the right lateral nasal wall.
Sagittal section. Removed: Sphenopalatine foramen.
Fig. 43.9 Nerves of the nasal cavity
Anterior ethmoidal n.
(CN V1)
Left lateral view.
Olfactory bulb
with fibers (CN I)
Anterior
ethmoidal n.
(CN V1)
Olfactory
fibers (CN I)
External
nasal br.
CN V2
CN V1
Medial
nasal brs.
Inferior
posterior
nasal br.
CN V3
Nasopalatine n. (CN V2)
A
Nerves of the left side of the nasal septum.
Sphenopalatine
foramen
Pterygopalatine
ganglion (in
pterygopalatine
fossa)
Lateral
superior
posterior
nasal brs.
Pterygopalatine
ganglion
Trigeminal
ganglion
Medial superior
posterior nasal
brs. (CN V2)
Descending palatine a.,
greater and lesser
palatine nn.
Lateral
nasal brs.
Internal nasal brs.
Lesser
palatine nn.
Greater
palatine n.
B
Nerves of the right lateral nasal wall.
621
Head & Neck
Pterygopalatine Fossa
The pterygopalatine fossa is a small pyramidal space just inferior to the
apex of the orbit. It is continuous with the infratemporal fossa laterally
through the pterygomaxillary fissure. The pterygopalatine fossa is a
crossroad for neurovascular structures traveling between the middle
cranial fossa, orbit, nasal cavity, and oral cavity.
Fig. 43.10 Bony boundaries of pterygopalatine fossa
Foramen rotundum
Sphenoid,
greater wing
Pterygoid canal
Temporal bone,
squamous portion
Palatovaginal (pharyngeal)
canal
Maxilla,
tuberosity
Sphenopalatine
foramen
Width of
pterygomaxillary
fissure
Maxilla
Sphenoid
Lateral plate,
pterygoid process
Palatine
A
Left lateral view. The lateral approach
through the infratemporal fossa via
the pterygomaxillary fissure.
B
Left lateral view. This color-coded
version shows the location of the
role of palatine bone.
Foramen rotundum
(from middle cranial fossa)
Inferior orbital fissure
(to orbit)
Sphenopalatine foramen
(to nasal cavity)
Pterygoid canal
(from middle cranial fossa)
Greater palatine canal
(to oral cavity)
Palatovaginal (pharyngeal) canal
(from nasopharynx)
Pterygopalatine fossa
(via pterygomaxillary fissure)
Table 43.2
622
Communications of the Pterygopalatine Fossa
Communication
Direction
Via
Transmitted structures
Middle cranial fossa
Posterosuperiorly
Foramen rotundum
• Maxillary n. (CN V2)
Middle cranial fossa
Posteriorly in
anterior wall of
foramen lacerum
Pterygoid (vidian) canal
• N. of pterygoid canal, formed from:
◦◦ Greater petrosal n. (preganglionic parasympathetic fibers from CN VII)
◦◦ Deep petrosal n. (postganglionic sympathetic fibers from internal carotid plexus)
• A. of pterygoid canal
• Vv. of pterygoid canal
Orbit
Anterosuperiorly
Inferior orbital fissure
• Branches of maxillary n. (CN V2)
◦◦ Infraorbital n.
◦◦ Zygomatic n.
• Infraorbital a. and vv.
• Communicating vv. between inferior ophthalmic v. and pterygoid plexus of vv.
Nasal cavity
Medially
Sphenopalatine foramen
• Nasopalatine (sp) n. (CN V2), lateral and medial superior posterior nasal branches
• Sphenopalatine a. and vv.
Oral cavity
Inferiorly
Greater palatine canal
(foramen)
• Greater (descending) palatine n. (CN V2) and a.
• Branches that emerge through lesser palatine canals:
◦◦ Lesser palatine nn. (CN V2) and aa.
Nasopharynx
Inferoposteriorly
Palatovaginal
(pharyngeal) canal
• Pharyngeal branches of maxillary n. (CN V2), and pharyngeal a.
Infratemporal fossa
Laterally
Pterygomaxillary fissure
• Maxillary a., pterygopalatine (third) part
• Posterior superior alveolar n., a., and v.
tine ganglion synapse with ganglion cells that innervate the lacrimal,
small palatal, and small nasal glands. The sympathetic fibers of the
deep petrosal nerve (sympathetic root) and sensory fibers of the maxillary nerve (sensory root) pass through the pterygopalatine ganglion
without synapsing. The pterygopalatine structures can be seen from
the medial view in Fig. 43.8B, p. 621.
Fig. 43.11 Nerves in the pterygopalatine fossa
Left lateral view. For simplicity in a small, structurally compressed area,
numbers are used to identify the nerves. The key to these numbers is
found in Table 43.3 (below).
①
Fig. 43.12 Coronal view of the
pterygopalatine fossa
Pterygomaxillary
fissure
43 Nasal Cavity & Nose
The maxillary division of the trigeminal nerve (CN V2, see Fig. 40.9,
p. 567) passes from the middle cranial fossa through the foramen
rotun­dum into the pterygopalatine fossa. The parasympathetic pterygopalatine ganglion receives postganglionic fibers from the greater
petrosal nerve (the parasympathetic root of the nervus intermedius
branch of the facial nerve). The preganglionic fibers of the pterygopala-
④ Maxillary n. (CN V2)
Superior orbital
fissure
③ ⑧
②
④
Lacrimal n.
⑤
Posterior
superior
alveolar n.
Ganglionic
br.
Pterygopalatine
ganglion
① Infraorbital n.
⑥
Pharyngeal n.
Zygomaticotemporal n.
Inferior orbital
fissure
② Zygomatic n.
Zygomaticofacial n.
⑦
Infraorbital nn.
in foramen
Posterior superior
alveolar n.
Descending palatine nn.
⑥, ⑦ Gr./Ls.
palatine nn.
Dental/gingival br. of
superior alveolar nn.
Table 43.3
in foramen rotundum
Communicating br.
between CN V2 and
pterygopalatine
ganglion
⑤ N. of pterygoid
canal entering
ganglion
from behind
Pterygopalatine
ganglion
⑧ Posterior superior/
inferior lateral
nasal br. of CN V2
Nasopalatine n.
Medial/lateral
pterygopalatine
fossa boundaries
Nerves of the pterygopalatine fossa
Origin of structures
Passageway
Transmitted nerves
① Infraorbital n.
Orbit
Inferior orbital fissure
② Zygomatic n.
③ Orbital brs. (from CN V2)
Middle cranial fossa
Foramen rotundum
④ Maxillary n. (CN V2)
Base of skull
Pterygoid (Vidian) canal
⑤N
. of pterygoid canal
Greater palatine canal
⑥ Greater palatine n.
Lesser palatine canals
⑦ Lesser palatine nn.
Sphenopalatine foramen
⑧M
edial and lateral posterior
superior and posterior inferior
nasal brs. (from nasopalatine
n., CN V2)
Palate
Nasal cavity
623
44
Temporal Bone & Ear
Head & Neck
Temporal Bone
Fig. 44.1 Temporal bone
Left bone. The temporal bone consists of three major parts: squamous,
petrous, and tympanic (see Fig. 44.2).
Zygomatic
process
Temporal
surface
Articular
tubercle
Mastoid
foramen
Mandibular
fossa
A
Left lateral view.
External
acoustic meatus
Petrotympanic
fissure
Styloid
process
Mastoid
process
Tympanomastoid
fissure
Zygomatic
process
Carotid
canal
Articular
tubercle
Mandibular
fossa
External
acoustic meatus
Styloid
process
Mastoid
process
Jugular
fossa
Stylomastoid
foramen
Arterial
groove
Mastoid
notch
Mastoid
foramen
B
Inferior view.
Zygomatic
process
Internal
acoustic meatus
Mastoid
foramen
C
Medial view.
624
Petrous
apex
Groove for
sigmoid sinus
Styloid
process
Fig. 44.2 Parts of the temporal bone
Styloid
process
Tympanic
part
Petrous
part
Squamous
part
44 Temporal Bone & Ear
Squamous
part
Tympanic
part
Petrous
part
A
Left lateral view.
B
Inferior view.
Clinical box 44.1
Structures in the temporal bone
Internal
acoustic meatus
The mastoid process contains mastoid air cells that communicate with the
middle ear; the middle ear in turn communicates with the nasopharynx
via the pharyngotympanic (auditory) tube (A). Bacteria may use this
pathway to move from the nasopharynx into the middle ear. In severe
cases, bacteria may pass from the mastoid air cells into the cranial cavity,
causing meningitis.
Temporal bone,
petrous part
Cochlea
Anterior
semicircular
canal
45°
Lateral
semicircular
canal
90°
Chorda
tympani
Facial n. (CN VII)
Facial n. (CN VII),
vestibulocochlear n. (CN VIII)
B
The petrous portion of the temporal bone contains the middle and inner
ear as well as the tympanic membrane. The bony semicircular canals
are oriented at an approximately 45-degree angle from the coronal,
transverse, and sagittal planes (B).
Tympanic
membrane
Pharyngotympanic
(auditory) tube
Anterior
semicircular canal
Internal
carotid a.
Internal
jugular v.
A
Posterior
semicircular
canal
45°
Mastoid
air cells
Posterior
semicircular canal
Temporal
bone, squamous part
Mastoid process
Vestibule
Cochlea
Irrigation of the auditory canal with warm (44°C) or cool (30°C) water
can induce a thermal current in the endolymph of the semicircular
canal, causing the patient to manifest vestibular nystagmus (jerky eye
movements, vestibulo-ocular reflex). This caloric testing is important in
the diagnosis of unexplained vertigo. The patient must be oriented so that
the semicircular canal of interest lies in the vertical plane (C).
Canthomeatal
plane
30°
Lateral
semicircular
canal
C
External
acoustic meatus
Mastoid process
625
Head & Neck
External Ear & Auditory Canal
(see p. 634). The inner ear also contains the vestibular apparatus, the
organ of balance (see p. 634).
The auditory apparatus is divided into three main parts: external,
middle, and inner ear. The external and middle ear are part of the sound
conduction apparatus, and the inner ear is the actual organ of hearing
Fig. 44.3 Ear: Overview
Posterior
semicircular
canal
Lateral
semicircular
canal
Coronal section through right ear, anterior view.
Anterior
semicircular
canal
Vestibule
Vestibular root
Cochlear root
Vestibulocochlear n.
(CN VIII)
Cochlea
Malleus
Temporal bone,
petrous part
Stapes
Tensor
tympani
Tympanic
cavity
Incus
Pharyngotympanic
(auditory) tube
Tympanic
membrane
External
auditory canal
Clinical box 44.2
Styloid
process
Curvature of the external auditory canal
The external auditory canal is most curved in
its cartilaginous portion. When an otoscope
is being inserted, the auricle should be pulled
backward and upward so the speculum can
be introduced into a straightened canal.
Fig. 44.4 External auditory canal
Coronal section through right ear, anterior view. The tympanic membrane separates the external auditory canal from the tympanic cavity
(middle ear). The outer third of the auditory canal is cartilaginous, and
the inner two thirds are osseous (tympanic part of temporal bone).
Temporal bone, tympanic part
A Insertion of
otoscope.
Tympanic
membrane
Middle ear
Malleus
Sebaceous
and
cerumen
glands
External
auditory
canal
626
Incus
B Anterior
view.
Stapes
Head of
mandible
Bony part
Cartilaginous part
Tympanic
membrane
C Transverse
section.
Fig. 44.5 Structure of the auricle
Temporoparietal
Helicis
major
Helicis
minor
Posterior
auricular
Crura of
antihelix
Scaphoid
fossa
Superior auricular
(posterior part of
temporoparietal)
Triangular
fossa
External
auditory
canal
Antitragus
Tragus
Cymba conchae
External
auditory canal
Helix
44 Temporal Bone & Ear
The auricle of the ear encloses a cartilaginous framework that forms
a funnel-shaped receptor for acoustic vibrations. The muscles of the
auricle are considered muscles of facial expression, although they are
vestigial in humans.
B
Cartilage and muscles of the right auricle, right lateral view.
Tragus
Intertragic
incisure
Antitragus
Antihelix
Concha
Earlobe
A
Right auricle, right lateral view.
Fig. 44.6 Arteries of the auricle
Posterior
auricular a.
Parietal br.
Superior
auricular
Oblique muscle
of the auricle
Anterior
auricular
Transverse muscle
of the auricle
External
auditory
canal
Posterior
auricular
C
Cartilage and muscles of the right auricle, medial view of posterior
surface.
Frontal br.
Perforating brs.
Anterior
auricular aa.
Perforating brs.
Posterior
auricular
Transverse
facial a.
Anastomotic
arcades
Superficial
temporal a.
Maxillary a.
A
Right auricle,
lateral view.
Posterior
auricular a.
External
carotid a.
Posterior
auricular a.
B
Right auricle,
posterior view.
External carotid a.
Fig. 44.7 Innervation of the auricle
Auriculotemporal n.
(trigeminal n., CN V)
Facial n. (CN VII)
A
Right auricle,
lateral view.
Vagus n. (CN X) and
glossopharyngeal n.
(CN IX)
Lesser occipital nn.
and great auricular n.
(cervical plexus)
Facial n.
B
Right auricle,
posterior view.
627
Head & Neck
Middle Ear: Tympanic Cavity
Pharyngotympanic
(auditory) tube
Fig. 44.8 Middle ear
Right petrous bone, superior view. The tympanic cavity of the middle ear communicates
anteriorly with the pharynx via the pharyngotympanic (auditory) tube and posteriorly with
the mastoid air cells.
Tympanic cavity
Internal
carotid a.
Malleus
Incus
Cochlea
Anterior semicircular canal
Facial n.
Cochlear n.
External
auditory canal
Vestibular n.
Lateral semicircular canal
Vestibule
Cochlear
aqueduct
Fig. 44.9 Tympanic cavity and pharyngotympanic tube
Endolymphatic
sac
Medial view of opened tympanic cavity.
Cribriform plate
Sphenoid
sinus
Internal
carotid a. Hypophysis
Mastoid cells
Auricle
Posterior
semicircular
canal
Pharyngotympanic
tube, bony part
Sigmoid
sinus
Tympanic membrane
Superior
concha
Sigmoid sinus
Pharyngeal
tonsil
Internal jugular v.
Hard palate
Tensor veli
palatini
Internal carotid a.
Cartilaginous part
Oral cavity
Pharyngeal orifice
Membranous lamina
Levator veli
palatini
Uvula
Pharyngotympanic
(auditory) tube
Salpingopharyngeus
Boundaries of the tympanic cavity
Table 44.1
During chronic suppurative otitis media (inflammation of the middle ear), pathogenic bacteria may spread to adjacent regions.
Direction
Wall
Anatomical boundary
Neighboring structures
Anterior
Carotid
Opening to pharyngotympanic tube
Carotid canal
Lateral
Membranous
Tympanic membrane
External ear
Superior
Tegmental
Tegmen tympani
Middle cranial fossa
Infection
Meningitis, cerebral abscess (especially of temporal lobe)
Inner ear
Medial
Labyrinthine
Promontory overlying basal turn of cochlea
Inferior
Jugular
Temporal bone, tympanic part
Posterior
Mastoid
Aditus to mastoid antrum
CSF, cerebrospinal fluid.
628
CSF space (via petrous apex)
Abducent paralysis, trigeminal nerve irritation, visual
disturbances (Gradenigo’s syndrome)
Bulb of jugular v.
Sigmoid sinus
Sinus thrombosis
Air cells of mastoid process
Mastoiditis
Facial n. canal
Facial paralysis
Epitympanum
Fig. 44.10 Tympanic cavity
Stapes
44 Temporal Bone & Ear
A
Levels of the tympanic cavity. Anterior view.
The tympanic cavity is divided into three
levels: epi-, meso-, and hypotympanum.
Tendon of
tensor
tympani
Incus
Malleus
Mesotympanum
External
auditory
canal
Hypotympanum
Tympanic
membrane
Pharyngotympanic
(auditory)
tube
Aditus (inlet) to
mastoid antrum
Lesser petrosal n.
(from tympanic plexus)
Facial n. (CN VII) in
facial canal
Malleus
Prominence of lateral
semicircular canal
Incus
Chorda tympani
Prominence of
facial canal
Tensor tympani
Stapes
Tendon of
stapedius
Promontory
Tympanic
membrane
Tympanic
plexus
Tympanic n. (from
CN IX) via tympanic
canaliculus
B
Coronal section, anterior view
with the anterior wall removed.
Anterior semicircular canal
Geniculate
Roof of tympanic
cavity (tegmen tympani) ganglion Vestibular n. (CN VIII)
Posterior semicircular canal
Facial n. (CN VII)
Cochlear n. (CN VIII)
Lateral semicircular canal
Greater petrosal n.
Lesser petrosal n.
Oval window
Semicanal of
tensor tympani
Facial n.
in facial canal
Internal carotid a.
Sigmoid sinus,
(ghosted)
Pharyngotympanic
(auditory) tube
Promontory
Opening for tendon
of tensor tympani
Internal
carotid plexus
Mastoid air cells
Anterior wall of
tympanic cavity
Chorda tympani
Round
window
Tympanic
plexus
Internal
jugular v.
Tympanic n. entering
tympanic canaliculus
C
Anatomical relationships of the
tympanic cavity. Oblique sagittal
section showing the medial wall.
629
Head & Neck
Middle Ear: Ossicular Chain & Tympanic Membrane
Fig. 44.11 Auditory ossicles
Left ear. The ossicular chain consists of three small bones that establish
an articular connection between the tympanic membrane and the oval
window.
Incudomalleolar
joint
Head
Body
Malleus
Incus
Stapes
Long process
Oval window
(with anular
stapedial lig.)
Incudostapedial joint
Tympanic
membrane
Anterior
process
Malleus
Handle
Posterior
crus
Tympanic
cavity
Anterior
crus
Stapes
Base
A
Auditory ossicles in the middle ear. Anterior view.
B
Bones of the ossicular chain. Medial view of the left ossicular chain.
Fig. 44.15 Tympanic membrane
Fig. 44.12 Malleus (“hammer”)
Right tympanic membrane. The tympanic membrane is divided into
four quadrantsquadrants (I–IV).
Left ear.
Head
Articular
surface
for incus
Neck
Neck
Short
process
Incus
Malleolar
prominence
Neck
Lateral
process
Lateral
process
Posterior
malleolar fold
A
Posterior view.
B
Anterior view.
Anterior
malleolar fold
Stapes
IV
Pars tensa
I
Umbo
Temporal bone,
tympanic part
Fig. 44.13 Incus (“anvil”)
Pars flaccida
Incus
Handle
Anterior
process
Tympanic incisure
Malleolar stria
III
II
Cone of light
Left ear.
Body
Body
Articular
surface for
malleus
Short
process
Short
process
Long
process
A
Medial view.
Lenticular
process
B
Anterolateral view.
Left ear.
Neck
630
Superior
malleolar fold
Chorda
tympani
Malleolar
stria
Head
A
Superior view.
Incus
Stapedius
tendon
Fig. 44.14 Stapes (“stirrup”)
Posterior
crus
A
Lateral view of the right tympanic membranewith quadrants
­indicated.
Anterior
crus
Umbo
Base
B
Medial view.
Malleus
Lateral lig.
of malleus
Superior recess
of tympanic
membrane
Malleolar
prominence
Tympanic
membrane
B
Mucosal lining of the tympanic cavity. Posterolateral view with the
tympanic membrane partially removed.
Fig. 44.16 Ossicular chain in the tympanic cavity
Lateral view of the right ear. Revealed: Ligaments of the ossicular chain
and muscles of the middle ear (stapedius and tensor tympani).
Superior ligs. of
the incus and malleus
Incus
Incudomalleolar joint
Anular
stapedial lig.
Malleus
Tendon of
tensor tympani
Stapedial
membrane
44 Temporal Bone & Ear
Posterior lig.
of incus
Tensor tympani
Incudostapedial joint
Internal carotid a.
Pyramidal eminence
Petrotympanic
fissure
Stapedius
Anterior lig.
of malleus
Stylomastoid a.
Chorda tympani
Facial n.
(CN VII)
Posterior
tympanic a.
Chorda
tympani
Tympanic
membrane
Anterior process
of malleus
Anterior
tympanic a.
Clinical box 44.3
Ossicular chain in hearing
Sound waves funneled into the external auditory canal set the tympanic
membrane into vibration. The ossicular chain transmits the vibrations to the
oval window, which communicates them to the fluid column of the inner ear.
Sound waves in fluid meet with higher impedance; they must therefore be
amplified in the middle ear. The difference in surface area between the tympanic
Malleus
Malleus
Incus
Axis of
movement
membrane and the oval window increases the sound pressure 17-fold. A total
amplification factor of 22 is achieved through the lever action of the ossicular
chain. If the ossicular chain fails to transform the sound pressure between the
tympanic membrane and the footplate of the stapes, the patient will experience
conductive hearing loss of magnitude 20 dB.
Incus
Oval
window
Stapes
Stapes
A
Vibration of the tympanic membrane causes a rocking movement in
the ossicular chain. The mechanical advantage of the lever action of the
ossicular chain amplifies the sound waves by a factor of 1.3.
Pyramidal
eminence
B
The stapes in its normal position lies in the plane of the
oval window.
Stapedius
tendon
Anular stapedial lig.
Oval
window
Round
window
Oval window
with anular
stapedial lig.
Basilar
membrane
Tympanic
membrane
DPropagation of sound waves by the ossicular chain.
C
Rocking of the ossicular chain causes the stapes to tilt. The
movement of the stapes base against the membrane of the
oval window (stapedial membrane) induces corresponding
waves in the fluid column of the inner ear.
631
Head & Neck
Arteries of the Middle Ear
A
Internal carotid a.
F
D
Middle meningeal a.
GS
H
J
Maxillary a.
Ascending pharyngeal a.
Posterior auricular a.
Occipital a.
External carotid a.
Table 44.2
Principal arteries of the middle ear
Origin
Artery
Distribution
Internal carotid a.
① Caroticotympanic aa.
Tympanic cavity (anterior wall), pharyngotympanic (auditory) tube
Ascending pharyngeal a.
(medial br.)
External carotid a.
Maxillary a.
(terminal br.)
② Inferior tympanic a.
Tympanic cavity (floor), promontory
③ Deep auricular a.
Tympanic cavity (floor), tympanic membrane
④ Anterior tympanic a.
Tympanic membrane, mastoid antrum, malleus, incus
Middle meningeal a.
Posterior auricular a.
(posterior br.)
Stylomastoid a.
⑤ Superior tympanic a.
Tympanic cavity (roof), tensor tympani, stapes
⑥ Stylomastoid a.
Tympanic cavity (posterior wall), mastoid air cells, stapedius m.,
stapes
⑦ Posterior tympanic a.
Chorda tympani, tympanic membrane, malleus
Fig. 44.17 Arteries of the middle ear:
Ossicular chain and tympanic membrane
Medial view of the right tympanic membrane. With inflammation,
the arteries of the tympanic membrane may become so
dilated that their course can be observed
(as shown here).
Tegmen
tympani
Incus
Mastoid
antrum
Superior
tympanic a.
Facial n. (CN VII)
Tensor tympani
Stapedial br.,
stylomastoid a.
Incudostapedial joint
(stapes removed)
Chorda tympani
Anterior
tympanic a.
Handle
of malleus
Posterior
tympanic a.
Pharyngotympanic
(auditory) tube
Stylomastoid a.
Tympanic
membrane
632
Deep auricular a.
Inferior tympanic a.
44 Temporal Bone & Ear
Fig. 44.18 Arteries of the middle ear: Tympanic cavity
Right petrous bone, anterior view. Removed: Malleus, incus, portions of
chorda tympani, and anterior tympanic artery.
Anterior semicircular
canal
Subarcuate a.
Superficial petrosal
a., ascending br.
Internal
auditory a.
Facial n. (CN VII)
Superficial
petrosal a.,
descending br.
Superficial petrosal a.
Greater petrosal n.
Superior tympanic a.
Anterior
crural a.
Lesser petrosal n.
Internal
carotid a.
Posterior
crural a.
Stylomastoid a.,
posterior
tympanic br.
Stapedial br.
Stapedius
Promontory
Pharyngotympanic
(auditory) tube
Tubal a.
Facial n. (CN VII)
Tensor
tympani
Stylomastoid a.
Caroticotympanic aa.
Tympanic n.
Mastoid a.
Stylomastoid a.,
posterior
tympanic br.
Deep auricular a. Inferior tympanic a.
Clinical box 44.4
Otitis Media
Hyperacusis
Otitis media is an infection of the middle ear that occurs commonly
in children often following an upper respiratory tract infection. Fluid
that accumulates in the middle ear can temporarily diminish hearing
and inflammation of the lining of the tympanic cavity can block the
pharyngotympanic tube.
The stapedius muscle protects the delicate inner ear by modifying the
vibrations of very loud sounds as they are transmitted through the middle
ear to the stapes. Paralysis of the muscle resulting from a lesion of the
facial nerve causes an extreme sensitivity to sound, a condition known as
hyperacusis.
633
Head & Neck
Inner Ear
The inner ear consists of the vestibular apparatus (for balance) and the
auditory apparatus (for hearing). Both are formed by a membranous
labyrinth filled with endolymph floating within a bony labyrinth filled
with perilymph and embedded in the petrous part of the temporal bone.
Fig. 44.19 Vestibular apparatus
Right lateral view.
Endolymphatic
duct
Semicircular
canals
Anterior
ampullary n.
Anterior semicircular canal
Superior
part
Anterior semicircular duct
Inferior
part
Lateral
ampullary n.
Utricle
Ductus Saccule
reuniens
Utricle
(with utricular n.)
Endolymphatic
sac
A
Schematic. Ampullary crests and maculae
of utricle and saccule shown in red.
Vestibular
ganglion
(CN VIII)
Lateral
semicircular canal
Saccule
(with saccular n.)
Posterior
semicircular canal
Posterior
ampullary n.
Endolymphatic
duct
Ductus
reuniens
B
Structure of the vestibular apparatus.
Fig. 44.20 Auditory apparatus
The cochlear labyrinth and its bony shell form the cochlea, which contains the sensory epithelium of the auditory apparatus (organ of Corti).
Modiolus
Scala vestibuli
Cochlear duct
Scala tympani
Oval
window
Round
window
Greater
petrosal n.
Lesser
petrosal n.
Helicotrema
Cochlear
canal
Cochlear aqueduct
Geniculate
ganglion
Cochlea
Tympanic
cavity
Cochlear n.
A
Schematic.
Facial n.
Vestibular n.
Chorda
tympani
Scala vestibuli
Cochlear
duct
Spiral
ganglion
Temporal bone,
petrous part
Scala tympani
B
Compartments of the
cochlear canal, cross section.
634
Internal
acoustic
meatus
Semicircular canals
C
Location of the cochlea. Superior view of the petrous part of the
temporal bone with the cochlea sectioned transversely. The bony
canal of the cochlea (spiral canal) makes 2.5 turns around its bony
axis (modiolus).
Fig. 44.21 Innervation of the membranous labyrinth
Anterior semicircular duct
Anterior
ampullary n.
divided into the vestibular and cochlear nerves. Note: The sensory organs in the semicircular canals respond to angular acceleration, and the
macular organs respond to horizontal and vertical linear acceleration.
Vestibular
Vestibuloganglion,
cochlear n. (CN VIII),
superior part
vestibular part
Vestibular
aqueduct
Facial n. (CN VII)
Vestibular
ganglion,
inferior part
Dura mater
Cochlear communicating br.
Endolymphatic
sac
44 Temporal Bone & Ear
Right ear, anterior view. The vestibulocochlear nerve (CN VIII; see
p. 570) transmits afferent impulses from the inner ear to the brainstem
through the internal acoustic meatus. The vestibulocochlear nerve is
Nervus intermedius
Lateral
ampullary n.
Vestibulocochlear n.
(CN VIII), cochlear part
Common crus
Saccular n.
Utricular n.
Posterior
ampullary n.
Lateral
semicircular
duct
Modiolus
Posterior
semicircular
duct
Spiral
ganglion
of cochlea
Posterior
ampulla
Oval
window
Round
window
Fig. 44.22 Blood vessels of the inner ear
Right anterior view. The labyrinth receives its blood supply from
the internal auditory artery, a branch of the anteroinferior
cerebellar artery (see p. 688).
Vestibular a.
Vestibular
ganglion
Vestibular n.
(CN VIII)
Facial n. (CN VII)
V. of vestibular
aqueduct
Internal auditory
a. and vv.
Nervus
intermedius
Cochlear n. (CN VIII)
Common
cochlear a.
Vestibulocochlear a.
Cochlear a.
proper
V. of round
window
V. of cochlear aqueduct
635
45
Oral Cavity & Pharynx
Head & Neck
Bones of the Oral Cavity
Fig. 45.1 Hard palate
The floor of the nasal cavity (the maxilla and
palatine bone) forms the roof of the oral cavity,
the hard palate. The two horizontal processes
of the maxilla (the palatine processes) grow to­
gether during development, eventually fusing
at the median palatine suture. Failure to fuse
results in a cleft palate.
Incisive fossa
Palatine process
of maxilla
Transverse
palatine suture
Median
palatine suture
Greater palatine
foramen
Lesser
palatine foramen
Inferior orbital
fissure
Pterygoid process,
medial plate
Pyramidal process
Pterygoid
fossa
Choana
Posterior nasal
spine
Pterygoid process,
lateral plate
Foramen for
pterygoid plexus
A Inferior view.
Vomer
Pterygoid canal
Foramen
ovale
Anterior
nasal spine
Maxillary
sinus
Nasal crest
Palatine process
of maxilla
Transverse
palatine suture
Perpendicular
plate
Greater
palatine canal
Pyramidal
process
BSuperior view.
Removed: Maxilla (upper part).
Lateral
plate
Posterior
nasal spine
Medial plate
Septum of
sphenoid sinus
Optic canal
Sphenoid,
lesser wing
Superior
orbital fissure
Ostium of
sphenoid sinus
Middle
concha
Pterygoid
fossa
Ethmoid bone,
perpendicular plate
Inferior
orbital fissure
Inferior
concha
Choana
Vomer
Median
palatine suture
636
Pterygoid
process
Anterior
clinoid process
C Oblique posterior view.
Palatine
bone
Incisive
foramen
Lateral
plate
Medial plate
Palatine bone
Palatine process of maxilla
Pterygoid
process
Head (condyle)
of mandible
Internal
oblique ridge
Oblique
line
External
oblique
ridge
The mandible (jaw) is connected to the viscero­
cranium at the temporomandibular joint (p. 638).
Coronoid
process
Ramus
of mandible
Mental
protuberance
Head (condyle) of
mandible
Alveolar
process
Coronoid
process
Alveoli
(tooth sockets)
Mental
foramen
Mental
tubercles
Lingula
Internal
oblique
ridge
Mandibular
foramen
Mylohyoid
groove
Body of
mandible
A
Anterior view.
Mandibular
notch
45 Oral Cavity & Pharynx
Neck of
mandible
Fig. 45.2 Mandible
Pterygoid
fovea
Head (condyle)
of mandible
Sublingual
fossa
Submandib­
ular fossa
Pterygoid
fovea
Coronoid
process
Condylar process
Superior
and inferior
mental spines
(genial tubercles)
Mandibular
foramen
Lingula
Digastric
fossa
Mylohyoid
line
B
Posterior view.
Ramus
of mandible
Alveolar
process
Mental
protuberance
Angle
Mental
tubercle
Mental
foramen
External
Body of Oblique
oblique ridge
mandible
line
C
Oblique left lateral view.
Fig. 45.3 Hyoid bone
The hyoid bone is suspended in the neck by muscles between the floor
of the mouth and the larynx. Although not listed among the cranial
Lesser horn
Greater horn
bones, the hyoid bone gives attachment to the muscles of the oral
floor. The greater horn and body of the hyoid are palpable in the neck.
Lesser horn
Greater horn
Lesser horn
Body
A
Anterior view.
Greater horn
Body
B
Posterior view.
C
Oblique left lateral view.
637
Head & Neck
Temporomandibular Joint
Fig. 45.4 Temporomandibular joint
Head of
mandible
The head of the mandible articulates with the mandibular fossa in the
temporomandibular joint.
Articular tubercle
Mandibular fossa
Pterygoid
fovea
Neck of
mandible
Coronoid
process
Articular disk
Neck of
mandible
Lingula
Mandibular
foramen
Head of mandible
Mylohyoid
groove
B
Head of mandible,
anterior view.
CHead of mandible,
posterior view.
A
Sagittally sectioned temporoman­
dibular joint, left lateral view.
Zygomatic process,
temporal bone
Articular
tubercle
DMandibular fossa
of the temporo­
mandibular joint,
inferior view.
Petrotympanic
fissure
Mandibular
fossa
External
acoustic meatus
(to external
auditory canal)
Styloid process,
temporal bone
Mastoid process,
temporal bone
Fig. 45.5 Ligaments of the temporomandibular joint
Pterygoid process, lateral plate
Pterygospinous
lig.
Joint
capsule
Lateral lig.
Spheno­
mandibular lig.
Stylomandibular lig.
Stylomandibular lig.
A
Lateral view of the left temporomandibular joint.
638
Pterygoid process,
medial plate
B
Medial view of the right temporomandibular joint.
Fig. 45.6 Movement of the temporomandibular joint
Clinical box 45.1
Lateral pterygoid,
superior head
Dislocation of the
temporomandibular joint
Articular
tubercle
Mandibular fossa
Dislocation may occur if the head of the
mandible slides past the articular tubercle.
The mandible then becomes locked in a
protruded position, a condition reduced by
pressing on the mandibular row of teeth.
Articular disk
Head of mandible
Joint capsule
45 Oral Cavity & Pharynx
Left lateral view. During the first 15 degrees of mandibular depression
(opening of the mouth), the head of the mandible remains in the man­
dibular fossa. Past 15 degrees, the head of the mandible glides forward
onto the articular tubercle.
Lateral pterygoid,
inferior head
A
Mouth closed.
15°
Fig. 45.7 Innervation of the
temporo­mandibular joint capsule
Superior view.
Auriculotemporal n.
Mandibular n.
(CN V3)
Deep temporal n.
B
Mouth opened to
15 degrees.
Masseteric n.
Articular tubercle
>15°
Mandibular fossa
Articular disk
Joint capsule
C
Mouth opened past
15 degrees.
639
Teeth
Head & Neck
Enamel
Fig. 45.8 Structure of a tooth
Crown
Crown
Each tooth consists of hard tissue (enamel, dentin, cementum) and soft
tissue (dental pulp) arranged into a crown, neck (cervix), and root.
Dentin
Pulp chamber
Neck
Neck
Gingival
margin
Alveolar
bone
Root
Root
Cementum
Apex of root
Fig. 45.9 Permanent teeth
Incisive fossa
Histology of a tooth
B
(mandibular incisor).
A
Principal parts of
a tooth (molar).
Each half of the maxilla and mandible contains a set of three
anterior teeth (two incisors, one canine) and five posterior
(postcanine) teeth (two premolars, three molars).
Incisors
Fig. 45.10 Tooth surfaces
Interalveolar
septum
The top of the tooth is known as the occlusal
surface.
Canine
Incisive
suture
Premolars
Labial
Mesial
Median palatine
suture
Distal
Molars
Mesial
Transverse palatine
suture
Palatal
Distal
Buccal
Maxillary teeth. Inferior view of the maxilla.
A
Distal
Buccal
Lingual
Molars
Mesial
Premolars
Interalveolar
septum
B
Mandibular teeth. Superior view
of the mandible.
640
Distal
Canine
Incisors
Mesial
Labial
Fig. 45.11 Coding of the teeth
1
32
2
3
31
A
B
C
4
5
6
30
T S
29 28
E
D
7
R
27
wise fashion. The third upper right molar is 1; the second upper right
premolar is A.
F
G
9
8
10
Q
P
O
N
26
25
24
23
Fig. 45.12 Dental panoramic tomogram
The dental panoramic tomogram (DPT) is a survey radiograph that
­allows preliminary assessment of the temporomandibular joints, maxillary sinuses, maxillomandibular bone, and dental status (carious lesions,
M
22
H
I
12 13
11
L
21
J
K
20
14
15
18
45 Oral Cavity & Pharynx
In the United States, the 32 permanent teeth are numbered sequen­
tially (not assigned to quadrants). The 20 deciduous (baby) teeth are
coded A to J (upper arch), and K to T (lower arch), in a similar clock­
16
17
19
location of wisdom teeth, etc.). DPT courtesy of Dr. U. J. Rother, Director of
the Department of Diagnostic Radiology, Center for Dentistry and Oromaxillofacial Surgery, ­Eppendorf University Medical Center, Hamburg, Germany.
Maxillary
sinus
Nasal
septum
Orbit
Articular
tubercle
Mandibular
fossa
Condylar
process
16*
1*
17*
32
Impacted
third molar
(wisdom tooth)
Mandibular
angle
31
30
*Not fully erupted.
29
28
27
26
25
Bite guide
of scanner
Mandibular
canal
641
Head & Neck
Oral Cavity Muscle Facts
Fig. 45.13 Muscles of the oral floor
See pp. 516–517 for the infrahyoid muscles.
S
F
1b
G
D
1a
Styloid
process
Mastoid
process
A
Suprahyoid muscles,
left lateral view.
Digastric,
posterior
belly
Hyoglossus
Mylohyoid
Stylohyoid
Digastric,
intermediate tendon
Digastric,
anterior belly
Connective tissue sling
Infrahyoid
muscles
Hyoid bone
B
Left lateral view.
F
Sublingual
fold
D
1a
Sublingual
papilla
Oral mucosa
G
S
1b
Genioglossus
Mylohyoid
raphe
Geniohyoid
C
Suprahyoid muscles,
superior view.
Mylohyoid
Hyoid bone
Hyoglossus
Stylohyoid
DSuperior view of the mandible and hyoid bone.
642
Suprahyoid muscles
Table 45.1
Muscle
Origin
Insertion
Anterior belly
Mandible (digastric fossa)
1b
Posterior belly
Temporal bone (mastoid notch,
medial to mastoid process)
① Digastric
② Stylohyoid
Via an intermediate
tendon with a
fibrous loop
Temporal bone (styloid process)
③ Mylohyoid
Via a split tendon
Hyoid bone
(body)
Mandible (mylohyoid line)
④ Geniohyoid
Mandible (inferior mental spine)
⑤ Hyoglossus
Hyoid bone (superior border of
greater cornu)
Mylohyoid n.
(from CN V3)
Facial n. (CN
VII)
Action
Elevates hyoid bone (during swallowing),
assists in opening mandible
Via median tendon
of insertion
(mylohyoid raphe)
Mylohyoid n.
(from CN V3)
Tightens and elevates oral floor, draws
hyoid bone forward (during swallowing),
assists in opening mandible and moving
it side to side (mastication)
Body of hyoid bone
Anterior ramus
of C1 via
hypoglossal n.
(CN XII)
Draws hyoid bone forward (during
swallowing), assists in opening mandible
Hypoglossal n.
(CN XII)
Depresses and retracts the tongue
Sides of tongue
Fig. 45.14 Muscles of the soft palate
45 Oral Cavity & Pharynx
1a
Innervation
Hard
palate
Inferior view. The soft palate forms the pos­
terior boundary of the oral cavity, separating
it from the oropharynx.
Inferior orbital
fissure
Palatine
aponeurosis
Pterygoid
hamulus
Lateral pterygoid
plate
Musculus
uvulae
Uvula
Tensor veli
palatini
Levator veli
palatini
Oropharynx
(isthmus)
Opening of
carotid canal
Occipital condyles
Table 45.2
Muscles of the soft palate
Muscle
Origin
Tensor veli palatini
Medial pterygoid plate (scaphoid
fossa); sphenoid bone (spine);
cartilage of pharyngotympanic tube
Levator veli palatini
Cartilage of pharyngotympanic tube;
temporal bone (petrous part)
Musculus uvulae
Palatine
aponeurosis
Innervation
Action
Medial pterygoid
n. (CN V3)
Tightens soft palate; opens inlet to pharyngotympanic
(auditory) tube (during swallowing, yawning)
Raises soft palate to horizontal position
Uvula (mucosa)
Palatine
aponeurosis;
posterior nasal
spine
Tongue (side)
Palatine
aponeurosis
Palatoglossus*
Palatopharyngeus*
Insertion
Vagus n. via
pharyngeal plexus
Shortens and raises uvula
Elevates tongue (posterior portion); pulls soft palate onto tongue
Tightens soft palate; during swallowing pulls pharyngeal walls
superiorly, anteriorly, and medially
*For the palatoglossus, see Figs. 45.19, p. 646 and 45.24, p. 648; and for the palatopharyngeus, see Figs. 45.24, p. 648 and 45.29C, p. 653.
643
Head & Neck
Innervation of the Oral Cavity
Fig. 45.15 Trigeminal nerve in the oral cavity
Right lateral view.
Trigeminal n.
(CN V)
Maxillary division
(CN V2, via foramen
rotundum)
Pterygo­
palatine
ganglion
Posterior
Middle
Anterior
Superior
alveolar nn.
Zygomatic n.
Infraorbital n.
(and foramen)
Mandibular division
(CN V3, via foramen ovale)
Buccal n.
Auriculo­
temporal n.
Medial
pterygoid
nn.
Masseteric n.
Mylohyoid n.
Lingual n.
Inferior alveolar n.
(in mandibular canal)
Inferior dental brs.
Fig. 45.16 Neurovasculature of the hard palate
Mental n. (and foramen)
Inferior view. The hard palate receives sensory innervation primarily
from terminal branches of the maxillary division of the trigeminal nerve
(CN V2). The arteries of the hard palate arise from the maxillary artery.
Superior
labial brs.
Posterior
septal brs.
Anterior
and middle
superior
alveolar brs.
Nasopalatine n.
Nasopalatine n.
Incisive foramen
Median palatine
suture
Posterior
superior
alveolar brs.
Greater
palatine n.
Greater palatine
n. and a.
Greater palatine
foramen
Buccal n.
Lesser palatine
foramen
Vomer
Lesser palatine
n. and a.
Lesser palatine n.
A
Sensory innervation. Note: The buccal nerve is a branch of the man­
dibular division (CN V3).
644
Pterygoid process
B
Nerves and arteries.
The muscles of the oral floor have a complex nerve supply with con­
tributions from the trigeminal nerve (CN V3), facial nerve (CN VII), and
C1 spinal nerve via the hypoglossal nerve (CN XII).
Fig. 45.17 Innervation of the oral
floor muscles
Mandibular division (CN V3)
Inferior
alveolar n.
Chorda tympani (CN VII)
Geniculate
ganglion
Lingual n.
Mylohyoid n.
Tympanic
plexus
Trigeminal
ganglion
Facial n.
(CN VII)
Submandibular
ganglion
Mastoid
cells
Mandibular
division (CN V3)
Mylohyoid
Digastric,
anterior belly
Chorda
tympani
A
Mylohyoid nerve (CN V3). Left lateral view
with the left half of the mandible removed.
Stylomastoid
foramen
Lingual n.
Mastoid
process
Glossopharyngeal n.
(CN IX)
Stylohyoid br.
(with muscle)
Lingual n.
45 Oral Cavity & Pharynx
Trigeminal ganglion
Digastric br.
(with posterior belly)
Facial nerve (CN VII). Sagittal section
B
through the right petrous bone at the level
of the mastoid process, medial view.
Hypoglossal
n. (CN XII)
Submandibular ganglion
C1 spinal n.,
anterior ramus
Genioglossus
Geniohyoid
Geniohyoid br. (C1)
Inferior root
of ansa cervicalis
(descendens cervicalis)
Superior root of
ansa cervicalis
(descendens hypoglossus)
Anterior rami of the C1 spinal nerve,
C
left lateral view.
Ansa cervicalis
645
Head & Neck
Tongue
The dorsum of the tongue is covered by a highly specialized mucosa
that supports its sensory functions (taste and fine tactile discrimina­
tion). The tongue is endowed with a very powerful muscular body to
support its motor properties during mastication, swallowing, and
speaking.
Palatopharyngeal fold
Fig. 45.18 Structure of the tongue
Epiglottis
Lingual tonsil
Superior view. The V-shaped sulcus terminalis divides the tongue into
an anterior 2/3rds (oral, presulcal) and a posterior 1/3rd (pharyngeal,
postsulcal).
Foramen
cecum
Fig. 45.19 Muscles of the tongue
The extrinsic lingual muscles (genioglossus, hyoglossus, palatoglossus,
and styloglossus) have bony attachments and move the tongue as a
whole. The intrinsic lingual muscles (superior and inferior longitudinal
muscles, transverse muscle, and vertical muscle) have no bony attach­
ments and alter the shape of the tongue.
Palatine
tonsil
Palato­
glossal
fold
Root of
tongue
Terminal
sulcus
Dorsum
of tongue
Dorsum of tongue
Palato­
glossus
Styloid
process
Body of
tongue
Median
furrow
Apex of
tongue
Apex of
tongue
Styloglossus
Mandible
Hyoglossus
Hyoid bone
Genio­
glossus
Genio­
hyoid
Superior view.
Taste
A
Left lateral view.
Vagus n.
(CN X)
Lingual aponeurosis Lingual mucosa
Superior longi­
tudinal m.
Transverse m.
Inferior longi­
tudinal m.
Hyoglossus
Genioglossus
Sublingual
gland
Mylohyoid
B
Coronal section,
anterior view.
646
Digastric, anterior
belly
Geniohyoid
Somatic sensation
Vagus n.
(CN X)
Glosso­
pharyngeal
n. (CN IX)
Vertical m.
Lingual septum
Fig. 45.20 Somatosensory and taste
innervation of the tongue
Glosso­
pharyngeal
n. (CN IX)
Facial n.
(CN VII, via
chorda
tympani)
Lingual n.
(CN V3)
Fig. 45.21 Neurovasculature of
the tongue
Apex of tongue
Anterior
lingual glands
Frenulum
Deep lingual
a. and v.
Sublingual
fold
Lingual n.
Submandibular
duct
Sublingual
papilla
Deep
lingual a.
Lingual n.
(CN V3)
45 Oral Cavity & Pharynx
The lingual muscles receive somatomotor
innervation from the hypoglossal nerve (CN
XII), with the exception of the palatoglossus
(supplied by the vagus nerve, CN X).
Styloid
process
A
Inferior surface of the tongue.
Glosso­
pharyngeal n.
(CN IX)
Submandibular
ganglion
Hypoglossal n.
(CN XII)
Lingual a. (from
external carotid a.)
Lingual v. (to
internal jugular v.)
Mandible
Submental
a. and v.
Medial
pterygoid
Sublingual a.
Mandibular n.
(CN V3)
Hyoid bone
Otic ganglion
B
Left lateral view.
Styloglossus
Sublingual
gland
Fig. 45.22 Floor of mouth
with tongue pulled from
midline
Right mandible, medial view. The
oral cavity is generally dissected
on a hemisected head. To see the
relationship of structures and the
base of the tongue/floor of the
mouth, the tongue is pulled out
of the plane of the dissection and
an incision is made in the mucosa
of the region.
Submandibular
duct
Hypoglossal n.
(CN XII)
Lingual a.
Sublingual
papilla
Submandibular
ganglion
Lingual n.
Submandibular gland,
deep part
Genioglossus
External
carotid a.
Hypoglossal n.
(CN XII)
Tongue
Mylohyoid
647
Head & Neck
Topography of the Oral Cavity & Salivary Glands
Fig. 45.23 Divisions of the oral cavity
The oral cavity is located below the nasal cavity and anterior
to the pharynx. It is bounded by the hard and soft palates,
the tongue and muscles of the oral floor, and the uvula.
Airway
Midsagittal section, left lateral view.
Foodway
Torus tubarius with
lymphatic tissue
(tubal tonsils)
Pharyngeal tonsil
Naso­
pharynx
Pharyngeal orifice of
pharyngotympanic
(auditory) tube
Dens of axis (C2)
Atlas (C1)
Salpingopharyngeal
fold
Palatine tonsil
Right choana
Oro­
pharynx
Soft palate
Laryngo­
pharynx
Uvula
Palatoglossal
fold
Organization of
A
the oral cavity.
Lingual tonsil
Genioglossus
Geniohyoid
Epiglottis
Hyoid bone
Thyrohyoid lig.
Divisions of the oral cavity
Table 45.3
Part
Anterior boundary
Posterior boundary
Oral vestibule
Lips/cheek
Dental arches
Oral cavity proper
Dental arches
Palatoglossal arch
Fauces (throat)
Palatoglossal arch
Palatopharyngeal arch
Ventricle
Vestibular
fold
Cricoid
cartilage
Vocal fold
Thyroid
gland
B
Boundaries of the oral cavity.
Fig. 45.24 Oral cavity topography
Right side, anterior view.
Soft palate
Palatoglossal
arch
Oral vestibule
Pterygomandibular
raphe
Lingual n.
Pterygomandibular
fold
Palatine tonsil
Palatopharyngeal
arch
Palatoglossus
Buccal n.
Palatopharyngeus
Medial pterygoid
Palatine tonsil
Uvula
Tongue
A Open oral cavity.
648
B
Oral cavity with mucosa removed from the roof and walls.
The three large, paired salivary glands are the parotid, submandibular,
and sublingual glands. The parotid gland is a purely serous (watery)
salivary gland. The sublingual gland is predominantly mucous; the
submandibular gland is a mixed seromucous gland.
Parotid gland
Parotid duct
Fig. 45.25 Salivary glands
Superficial temporal
a. and v.
45 Oral Cavity & Pharynx
Accessory parotid gland
Parotid
gland,
superficial
part
Parotid
plexus
Facial n.
(CN VII)
Buccinator
Parotid gland,
deep part
Masseter
Facial a.
and v.
Submandibular
gland, super­
ficial part
B
Facial nerve in the parotid gland, left lateral
view. The branching of the facial nerve into
the parotid plexus (see p. 568) separates
the parotid gland into a superficial part
and a deep part.
Sternocleido­
mastoid
A
Parotid gland, left lateral view. Note: The
parotid duct penetrates the buccinator
muscle to open opposite the second
upper molar.
Sternocleido­
mastoid
Sublingual
papilla
Sublingual
fold
Oral mucosa
Genioglossus
Sublingual
gland
Submandibular
duct
Geniohyoid
Mylohyoid
Lingual n.
Submandib­
ular gland,
deep part
Inferior
alveolar n.
Mylohyoid n.
Lingual a.
C
Submandibular and sublingual glands,
superior view with tongue removed.
Hyoid bone
Hyoglossus
Submandib­
ular gland,
superficial
part
Stylohyoid
649
Head & Neck
Tonsils & Pharynx
Fig. 45.26 Tonsils
Choana
Soft
palate
Roof of pharynx
Palato­
glossal arch
Palato­
pharyngeal
arch
Tonsillar
fossa
Uvula
Palatine
tonsil
Nasal
septum
Pharyngeal
tonsil
Torus
tubarius with
lymphatic
tissue (tubal
tonsils)
Pharyngeal
orifice of
pharyngo­
tympanic
tube
Soft
palate
Dens of axis
(C2)
Salpingo­
pharyngeal
fold
A
Palatine tonsils, anterior view.
Uvula
Pharyngeal
tonsil*
Nasal
conchae
Soft palate
Roof of
pharynx
B
Pharyngeal tonsils. Sagittal section
through the roof of the pharynx.
Tubal tonsil*
(extension of
pharyngeal
tonsil)
Uvula
Lymphatic tissue
of lateral bands*
along salpingo­
pharyngeal fold
Palatine
tonsil*
Lingual
tonsil*
Epiglottis
Waldeyer’s ring. Posterior view
C
of the opened pharynx.
650
Table 45.4
Structures in
Waldeyer’s ring
Tonsil*
#
Pharyngeal tonsil
1
Tubal tonsils
2
Palatine tonsils
2
Lingual tonsil
1
Lateral bands
2
Clinical box 45.2
Abnormal enlargement of the
palatine tonsils due to severe
viral or bacterial infection can
result in obstruction of the
oropharynx, causing difficulty
swallowing.
Enlarged palatine tonsil
Particularly well developed in
young children, the pharyngeal
tonsil begins to regress at 6 to
7 years of age. Abnormal
enlargement is common, with
the tonsil bulging into the
nasopharynx and obstructing
air passages, forcing the child to
“mouth breathe.”
Choana
Enlarged
pharyngeal tonsil
45 Oral Cavity & Pharynx
Tonsil infections
Fig. 45.27 Pharyngeal mucosa
Posterior view of the opened pharynx. The anterior portion of the
muscular tube contains three openings: choanae (to the nasal cavity),
faucial isthmus (to the oral cavity), and aditus (to the laryngeal inlet).
Sigmoid
sinus
Pharyngeal
tonsil
Middle nasal
concha
Nasal cavity
opening via choana
into nasopharynx
Nasal septum
Inferior nasal
concha
Stylohyoid
Digastric muscle,
posterior belly
Masseter
Soft palate
Oral cavity opening
via faucial isthmus
into oropharynx
Uvula
Medial pterygoid
Palatopharyngeal
arch
Aryepiglottic fold
Laryngeal inlet opening
into laryngopharynx
Root of tongue
(lingual tonsil)
Epiglottis
Cuneiform
tubercle
Piriform
recess
Corniculate
tubercle
Pharynx (cut)
Thyroid gland
651
Head & Neck
Pharyngeal Muscles
Fig. 45.28 Pharyngeal muscles:
Left lateral view
Tensor veli
palatini
Levator veli
palatini
The pharyngeal musculature consists of the
pharyngeal constrictors and the relatively
weak pharyngeal elevators.
Superior
pharyngeal
constrictor
Stylohyoid
Buccinator
Styloglossus
Digastric muscle,
posterior belly
Pterygo­
mandibular
raphe
Stylopharyngeus
Hyoglossus
Mylohyoid
Middle pharyngeal
constrictor
Digastric muscle,
anterior belly
Inferior pharyngeal
constrictor
Sternohyoid (cut)
Thyrohyoid
Cricothyroid
A
Pharyngeal muscles in situ.
Esophagus
S1
S2
S3
Superior
pharyngeal
constrictor
S4
M1
M2
Middle
pharyngeal
constrictor
I1
I2
Inferior
pharyngeal
constrictor
Table 45.5
Pharyngeal constrictors
Superior pharyngeal constrictor
S1
Pterygopharyngeal part
S2
Buccopharyngeal part
S3
Mylopharyngeal part
S4
Glossopharyngeal part
Middle pharyngeal constrictor
M1
Chondropharyngeal part
M2
Ceratopharyngeal part
Inferior pharyngeal constrictor
B
Subdivisions of the pharyngeal constrictors.
652
I1
Thyropharyngeal part
I2
Cricopharyngeal part
Fig. 45.29 Pharyngeal muscles:
Posterior view
45 Oral Cavity & Pharynx
Pharyngobasilar
fascia
Accessory
muscle bundle
Superior
pharyngeal
constrictor
Digastric muscle,
posterior belly
Masseter
Stylohyoid
Medial pterygoid
Stylopharyngeus
Middle pharyngeal
constrictor
Hyoid bone,
greater horn
Pharyngeal
tonsil
Inferior pharyngeal
constrictor
Pharyngeal
raphe
Pharyngotympanic
tube, cartilaginous
part
Levator veli
palatini
Salpingo­
pharyngeus
Esophagus
Tubal orifice
Tensor veli
palatini
Superior
pharyngeal
constrictor
Pterygoid process,
medial plate
Musculus uvulae
Palato­
pharyngeus
Pterygoid hamulus
B
Muscles of the soft palate and pharyngo­
tympanic tube. The muscles of the fauces
form the posterior boundary of the oral
cavity. Cut on right side: Levator veli palatini
and salpingopharyngeus.
A
Muscles of the posterior pharynx.
Tensor veli palatini
Levator veli palatini
Styloid process
Stylohyoid
Superior pharyngeal
constrictor
Digastric, posterior
belly
Masseter
Salpingo­
pharyngeus
Pharyngeal
elevators
Palato­
pharyngeus
Stylopharyngeus
Oblique arytenoid
Musculus uvulae
Medial
pterygoid
Angle of
mandible
Middle pharyngeal
constrictor
Transverse
arytenoid
Posterior
cricoarytenoid
Muscles in the opened pharynx.
C
Circular muscle fibers
of esophagus
653
Head & Neck
Neurovasculature of the Pharynx
Fig. 45.30 Neurovasculature in
the parapharyngeal space
Posterior view. Removed: Vertebral column
and posterior structures.
Pharyngobasilar
fascia
Sigmoid sinus
CN XI
Pharyngeal raphe
Occipital a.
CN XII
Superior pharyngeal
constrictor
Stylopharyngeus
Superior cervical
ganglion
Middle pharyngeal
constrictor
CN IX
Internal jugular v.
Superior laryngeal n.
External carotid a.
Sternocleido­
mastoid
Internal carotid a.
Ascending pharyngeal a.
CN XII
Carotid body
Pharyngeal venous plexus
Sympathetic trunk
Inferior pharyngeal
constrictor
Superior thyroid a.
CN X
Common carotid a.
Thyroid gland
Fig. 45.31 Fasciae and potential tissue spaces in the head
Transverse section at the level of the tonsillar fossa, superior view.
Fascial boundaries are key to outlining pathways for the spread of
infection. Potential spaces in the head, shown on this figure, become
true spaces when they are infiltrated by products of infection. These
spaces are defined by bones, muscles and fascia and initially confine
an infection but eventually allow it to spread through communications
between spaces.
Buccal space
Peritonsillar space
Submasseteric space
Parapharyngeal space
Pterygomandibular space
Parotid space
Retropharyngeal space
654
Posterior view.
Choanae
CN VI
CN III
CN V
Middle nasal
concha
CN VII, CN VIII,
nervus intermedius
Inferior nasal
concha
CN IX, X, XI
45 Oral Cavity & Pharynx
Fig. 45.32 Neurovasculature of the opened pharynx
CN VII
CN IX
Occipital a.
Musculus uvulae
Superior cervical ganglion
Palatopharyngeus
CN XII
Salpingopharyngeus
CN X
CN XI
Sternocleidomastoid
Superior laryngeal n.
Epiglottis
CN X
Sympathetic trunk
Cuneiform tubercle
Superior laryngeal
a. and internal
laryngeal n.
Corniculate tubercle
Inferior laryngeal v.
Oblique
part
Transverse
part
Internal jugular v.
Arytenoid
Posterior cricoarytenoid
Common carotid a.
Middle cervical ganglion
Inferior laryngeal n.
(terminal br. of
recurrent laryngeal n.)
Inferior thyroid a.
External jugular v.
Left subclavian a.
Right recurrent
laryngeal n.
Stellate ganglion
Brachiocephalic trunk
CN X, left
Left recurrent
laryngeal n.
CN X, right
CN III, oculomotor n.; CN V, trigeminal n.; CN VI, abducent n.;
CN VII, facial n.; CN VIII, vestibulocochlear n.; CN IX, glossopharyngeal n.;
CN X, vagus n.; CN XI, accessory n.; CN XII, hypoglossal n..
See Chapter 39 for the cranial nerves.
655
46
Sectional & Radiographic Anatomy
Head & Neck
Sectional Anatomy of the Head & Neck (I)
Fig. 46.1 Coronal section through the anterior
orbital margin
Anterior view. This section shows four regions of the head: the oral cavity, the nasal cavity and sinuses, the orbit, and the anterior cranial fossa.
Muscles of the oral floor, the apex of the tongue, the hard palate, the
neurovascular structures in the mandibular canal, and the first molar
are all seen in the region of the oral cavity. This section reinforces the
clinical implications of the relationship of the maxillary sinus with the
maxillary teeth and the floor of the orbit and with the maxillary nerve
in the infraorbital groove. The medial wall of the orbit shares a thin
bony wall (orbital plate) with the ethmoid air cells (sinus). The section
is enough anterior so that the lateral bony walls of the orbit are not
included due to the lateral curvature of the skull.
Anterior
cranial fossa
Frontal lobe
of cerebrum
Levator palpebrae
superioris
Periorbital fat
Orbital plate of
ethmoid bone
Vitreous body
Ethmoid
sinuses
Medial rectus
Inferior rectus
Middle nasal
meatus and
concha
Inferior oblique
Orbicularis oculi
Infraorbital n.
(from CN V2) in
infraorbital groove
Maxillary sinus
Cartilaginous
nasal septum
Inferior nasal
meatus
Inferior nasal
concha
Vomer
Palatine process
of the maxilla
First upper molar
Greater palatine a.
Buccinator
Oral cavity
Tongue
Oral vestibule
Genioglossus
Geniohyoid
Mylohyoid
Platysma
656
First lower molar
Inferior alveolar a., n., and
v. in mandibular canal
Digastric,
anterior belly
Fig. 46.2 Coronal section through the orbital apex
Superior
sagittal sinus
Falx cerebri
Frontal lobe
of cerebrum
46 Sectional & Radiographic Anatomy
Anterior view. In this more posterior section than that of Fig. 46.1, the
soft palate now separates the oral and nasal cavities. The buccal fat
pad is also visible. The section is slightly angled, producing an apparent
discontinuity in the mandibular ramus on the left side.
Olfactory n.
(CN I)
Superior oblique
Superior rectus
Lateral rectus
Temporalis
Optic n.
(CN II)
Ethmoid sinuses
Medial rectus
Inferior rectus
Nasal septum
Infraorbital n.
(from CN V2)
Zygomatic
arch
Masseter
Maxillary sinus
Nasal cavity
Coronoid process
Soft palate
Mandibular ramus
Buccal fat pad
Medial pterygoid
Buccinator
Tongue
Body of mandible
Genioglossus
Lingual n.,
deep lingual
a. and v.
Mylohyoid
Inferior alveolar n.,
a., and v. in
mandibular canal
Hyoglossus
Digastric,
anterior belly
Geniohyoid
657
Head & Neck
Sectional Anatomy of the Head & Neck (II)
Fig. 46.3 Coronal section through
the pituitary
Anterior view.
Superior
sagittal sinus
Falx cerebri
Lateral
ventricle
Corpus
callosum
Parietal
lobe
Caudate nucleus,
head
Internal capsule
Putamen
Temporalis
Anterior
cerebral a.
Optic n.
(CN II)
Oculomotor
n. (CN III)
Internal
carotid a.
Trochlear n.
(CN IV)
Temporal lobe
Abducent n.
(CN VI)
Hypophysis in
hypophyseal fossa
Cavernous sinus
Sphenoid sinus
Zygomatic
process,
temporal bone
Septum of
sphenoid sinus
Ophthalmic n.
(CN V1)
Maxillary n.
(CN V2)
Middle cranial
fossa
Mandibular n.
(CN V3)
Masseter
Lateral pterygoid
Nasopharynx
Lingual n.
Lingual n.
Inferior
alveolar n.
Inferior
alveolar n.
Mandible, ramus
Medial pterygoid
Uvula
Oropharynx
Epiglottis
Laryngopharynx
658
Palatine tonsil
Fig. 46.4 Midsagittal section
through the nasal septum
Left lateral view.
46 Sectional & Radiographic Anatomy
Corpus
callosum
Frontal
sinus
Anterior
cranial fossa
Olfactory
bulb (CN I)
Hypophysis
Sphenoid
sinus
Clivus
Transverse
sinus
Choana
Foramen
magnum
Nasal septum
Atlas (C1),
anterior and
posterior arches
Hard palate,
maxilla (palatine
process)
Nuchal lig.
Soft
palate
Transverse
lig. of atlas
Nasopharynx
Median
atlantoaxial joint
Uvula
Axis (C2), dens
Mandible
C3 vertebra
Oropharynx
Geniohyoid
Mylohyoid
Vallecula
Hyoid bone
Laryngeal cartilage
Epiglottis
Laryngopharynx
659
Head & Neck
Sectional Anatomy of the Head & Neck (III)
Fig. 46.5 Sagittal section through the medial
orbital wall
Left lateral view. This section passes through the inferior and middle
conchae of the lateral nasal wall. Three of the four paranasal air sinuses
(ethmoid, sphenoid, and frontal) are seen in this section and in relation
to the nasal cavity into which they drain. In the region of the cervical
Caudate nucleus,
head
Internal
capsule
spine, the vertebral artery is cut at multiple levels. The spinal nerves
have been cut just prior to their lateral exit through the intervertebral
foramina.
Medial segment of
globus pallidus
Uncus
Lateral
ventricle
Posterior
thalamic
nuclei
Oculomotor
n. (CN III)
Optic n.
(CN II)
Pontocerebellar
cistern
Frontal
sinus
Tentorium
cerebelli
Ethmoid
sinus
Cerebellum
Pharyngotympanic
(auditory)
tube
Sphenoid
sinus
Middle
nasal concha
Vertebral a.
Inferior
nasal concha
Rectus capitis
posterior minor
Palatine process,
palatine sulcus
Semispinalis
capitis
Maxilla
Rectus capitis
posterior major
Superior labial
vestibule
C2 spinal n.
Oral cavity
Palatopharyngeus
Obliquus
capitis inferior
Inferior labial
vestibule
Longus capitis
Tongue
Splenius capitis
Mandible
Lingual n.
and deep
lingual vv.
C3 spinal n.
Spinalis cervicis
Digastric,
anterior belly
C4 spinal n.
Mylohyoid
Hyoid bone
Epiglottic
cartilage and
vallecula
660
Laryngopharynx
Thyroid
cartilage
Vertebral
a.
C5 spinal
n.
C6 spinal
n.
C7 spinal n.
Left lateral view. This section passes through the maxillary, frontal, and
sphenoid sinuses and a single ethmoidal air cell. The pharyngeal and
masticatory muscles are revealed grouped around the cartilaginous
Extreme
capsule
External
capsule
Claustrum
part of the pharnygotympanic (auditory) tube. The palatine tonsil of
the oral cavity and medial portion of the submandibular gland below
the floor of the mouth are also seen in this section.
Putamen
Internal
capsule
Dentate
gyrus
Amygdala
Trigeminal
ganglion (CN V)
46 Sectional & Radiographic Anatomy
Fig. 46.6 Sagittal section through the inner
third of the orbit
Internal
carotid a.
Lateral
rectus
Superior
rectus
Pharyngotympanic
(auditory) tube
Frontal sinus
Posterior
meningeal
a.
Optic n. (CN II)
Procerus
CN IX, X, and XI
in jugular foramen
Inferior
rectus
Vitreous body
CN V2 in
pterygopalatine fossa
Hypoglossal n.
(CN XII)
Transverse
sinus
Ethmoid sinus
Sphenoid
sinus
Lateral
pterygoid
Condylar
emissary v.
Rectus capitis
posterior major
Levator veli
palatini
Medial
pterygoid
Semispinalis capitis
Internal carotid a.
Maxillary sinus
Obliquus
capitis inferior
Palatine tonsil
Orbicularis
oris
Greater occipital
n. (C2)
Palatopharyngeus
Vertebral a.
C3 spinal n.
Tongue
Trapezius
Genioglossus
Mylohyoid
Splenius capitis
Digastric,
anterior belly
Retropharyngeal
space
Hyoid bone,
lesser cornu Submandibular
gland
Hyoid bone,
greater cornu
Thyroid cartilage,
left lamina
Inferior pharyngeal
constrictor
661
Head & Neck
Sectional Anatomy of the Head & Neck (IV)
Fig. 46.7 Transverse section through
the optic nerve and pituitary
Inferior view.
Nasal cavity
Lens
Vitreous
body
Lacrimal gland
Optic n.
(CN II)
Nasal septum
Ethmoid
sinuses
Medial
rectus
Lateral
rectus
Optic canal
Internal
carotid a.
Temporalis
Hypophysis
Oculomotor n.
(CN III)
Cavernous
sinus
Pons
Cerebellum,
vermis
Dorsum
sellae
Basilar a.
Interpeduncular
fossa
Tentorium
cerebelli
Inferior sagittal
sinus
Lateral ventricle,
occipital horn
Falx cerebri
Superior sagittal
sinus
662
Superior view. This section passes through the soft palate and mucoperiosteum of the hard palate. The articulation of the odontoid process
(dens of C2) with the axis (C1) at the median atlantoaxial joint is shown,
as well as the carotid sheath, containing the vertical neuro-
Soft palate (including
tensor and levator
veli palatini)
Maxilla
vascular elements of the neck. The vertebral artery is sectioned as it
prepares to enter the foramen magnum and fuse with its opposite to
form the basilar artery.
Mucoperiosteum
of hard palate
Lateral
pterygoid plate
Levator
anguli oris
46 Sectional & Radiographic Anatomy
Fig. 46.8 Transverse section of head through the median
atlantoaxial joint
Buccinator
Masseter
Lingual n.
Medial
pterygoid
Inferior
alveolar n.
Lateral
pterygoid
Atlas (C1)
Mandibular ramus
Glossopharyngeal n.
(CN IX)
Maxillary a.
Internal
carotid a.
Internal
jugular v.
Accessory n.
(CN XI)
Facial n.
(CN VII) in
parotid gland
Hypoglossal n.
(CN XII)
Vagus n.
(CN X)
Occipital a.
Median
atlantoaxial joint
Posterior condylar
emissary v.
Splenius
capitis
Dens of axis (C2)
Vertebral a.
Transverse
lig. of atlas
Occipital
bone
Spinal Trapezius
cord
Semispinalis
capitis
663
Head & Neck
Sectional Anatomy of the Head & Neck (V)
Fig. 46.9 Transverse section of the neck
Transverse section at the level of the C5 vertebral body. Inferior view.
The internal and external jugular veins are separated by the sternocleidomastoid. The accessory nerve (CN XI) is just medial to this muscle as
Arytenoid
cartilage
it prepares to innervate it from behind. The elongated spinous process
of the C7 vertebra (vertebra prominens) is also visible in the section
due to the lordotic curvature of the neck.
Epiglottic
cartilage
Laryngeal
vestibule
Platysma
Omohyoid
Piriform recess
Thyrohyoid
Superior thyroid v.
Thyroid cartilage
Common carotid a.,
internal jugular v.,
and vagus n. (CN X)
in carotid sheath
Sternocleidomastoid
Oropharynx
C5 vertebra
External jugular v.
Longus colli
Accessory n. (CN XI),
external branch
C4 spinal n.
Vertebral a.
C5 spinal n.
C6 vertebral
body
C6 spinal n.
Longissimus
capitis
Levator
scapulae
Longissimus
cervicis
Trapezius
Splenius
cervicis
Splenius
capitis
664
Spinous process
of C 7
Semispinalis
cervicis
Arytenoid
cartilage
Inferior view.
Thyroid
cartilage
Sternohyoid
Thyrohyoid
Superior thyroid v.
Laryngopharynx
Omohyoid
Common carotid a.,
internal jugular v.,
and vagus n. (CN X)
in carotid sheath
Thyroid gland
Sternocleidomastoid
Longus colli
Anterior scalene
with C5 spinal n.
C4 spinal n.
Vertebral v.
Middle scalene
C6 spinal n.
and C6 vertebra
Vertebral a.
Posterior scalene
C7 spinal n.
and C7 vertebra
Levator scapulae
T1, vertebral arch
Trapezius
Semispinalis
cervicis
Fig. 46.11 Transverse section of the neck
Transverse section at the level of the C7/T1 vertebral junction. Inferior
view. This section reveals the roots of spinal nerves C6 to C8 of the brachial plexus passing between the anterior and middle scalene muscles.
The phrenic nerve is on the anterior surface of the anterior scalene and
Superior thyroid v.
Cricoid cartilage
Superior thyroid a.
Internal jugular v.,
vagus n. (CN X), and
common carotid a.
Phrenic n. with
anterior scalene
External jugular v.
46 Sectional & Radiographic Anatomy
Fig. 46.10 Transverse section at the
level of the C6 vertebral body
Splenius
cervicis
the components of the carotid sheath (internal jugular vein, common
carotid artery, and vagus nerve) lie in the interval between this muscle,
the sternocleidomastoid, and the thyroid gland.
Sternohyoid
Sternothyroid
Thyroid gland
Sternocleidomastoid
Esophagus
Thyrocervical trunk
Inferior thyroid a.
C6 spinal n.
Vertebral a. and v.
C7 spinal n.
Middle scalene
C8 spinal n.
Intervertebral disk
T1 vertebra and
spinal n.
Posterior scalene
Second rib
Transverse process of T2
665
Head & Neck
Radiographic Anatomy of the Head & Neck (I)
Fig. 46.12 Radiograph of the skull
Anteroposterior view. (Reproduced from
Moeller TB, Reif E. Pocket Atlas of Radiographic Anatomy, 3rd ed. New York, NY:
Thieme; 2010.)
Frontal sinus
Roof of orbit
Ethmoidal air cells
Nasal septum and
inferior nasal concha
Maxillary sinus
Maxilla
Angle, mandible
Mental protuberance
Fig. 46.13 Coronal MRI through
the eyeball
Ethmoid sinus
Mandible
Superior
sagittal sinus
Falx cerebri with
superior frontal gyrus
Anterior view.
Roof of orbit
Levator palpebrae
superioris, superior rectus,
and supraorbital n.
Superior oblique with
superior ophthalmic v.
Lacrimal gland
Eyeball
Lateral rectus
Medial rectus with
ophthalmic a.
Inferior rectus and inferior
oblique
Periorbital fat
Zygomatic bone
Infraorbital
a., v., and n.
Middle and inferior
nasal conchae
Maxillary sinus
Nasal septum
Maxilla, alveolar process
Buccinator
Tongue
Mandibular
tooth
666
Genioglossus
Lingual n., deep
lingual a. and v.
Fig. 46.14 Radiograph of the skull
Coronal suture
Dorsum sellae
Frontal sinus
Hypophyseal fossa
(sella turcica)
Anterior clinoid process
Sphenoid sinus
Ethmoidal sinus
Clivus
Maxillary sinus
Hard palate
46 Sectional & Radiographic Anatomy
Left lateral view. (Reproduced from
Moeller TB, Reif E. Pocket Atlas of
Radiographic Anatomy, 3rd ed.
New York, NY: Thieme; 2010.)
Oral cavity
Manidble
Fig. 46.15 Midsagittal MRI through the nasal septum
Left lateral view. Boxed area represents the location of the ventricular
system, thalamus, and pons. A more detail labeled version of this area
can be seen in Fig. 51.5, p. 700. (Reproduced from Moeller TB, Reif E.
Hypophysis
Pocket Atlas of Sectional Anatomy, Vol 1, 4th ed. New York, NY:
Thieme; 2014.)
Optic
n. (CN II)
Septum
pellucidum
Superior
sagittal sinus
Ethmoid sinus and
sphenoid sinus
Corpus callosum
Straight sinus
Fourth ventricle
Confluence of the sinuses
Frontal sinus
Nasal bone
Basilar a.
Nasopharynx
Rectus capitis posterior minor
Nuchal lig.
Hard palate
Dens of axis (C2) and
anterior arch of atlas (C1)
Tongue
C2/C3 intervertebral disk
Mandible,
body
Uvula
Oropharynx
Semispinalis
capitis
667
Head & Neck
Radiographic Anatomy of the Head & Neck (II)
Fig. 46.16 Radiograph
of the skull
Inferosuperior oblique view
(Waters view). (Reproduced
Frontal sinus
from Moeller TB, Reif E.
Pocket Atlas of Radiographic Anatomy, 3rd ed.
Nasal bone
New York, NY: Thieme;
2010.)
Orbit
Nasal septum
Infraorbital foramen
Maxillary sinus
Sphenoid sinus
Sphenoid sinus,
median septum
Oropharynx
Tongue
Mandible
Fig. 46.17 Radiograph
of the mandible
Left lateral view. (Reproduced from Moeller TB,
Reif E. Pocket Atlas of
Radiographic Anatomy,
3rd ed. New York, NY:
Thieme; 2010.)
Temporomandibular joint (TMJ)
Mandible, condyle
Coronoid process, mandible
Mandibular notch
Mandible
Mandibular foramen
Mental protuberance
Mandibular canal
Mental foramen
Apical foramen of tooth
Mandible, angle
668
Fig. 46.18 Transverse MRI
through the orbit and
nasolacrimal duct
Orbicularis oris
Middle nasal concha
Nasal septum
Nasal bone
Maxilla with
infraorbital canal
Levator labii superioris
Nasolacrimal duct
Maxillary sinus
Temporalis
Medial pterygoid
between medial and
lateral pterygoid plates
Masseter
Lateral pterygoid
Pharyngeal recess
Mandibular condyle
Levator and tensor
veli palatini
46 Sectional & Radiographic Anatomy
Inferior view. (Reproduced from
Moeller TB, Reif E. Pocket Atlas of
Sectional Anatomy, Vol 1, 4th ed.
New York, NY: Thieme; 2014.)
Mandibular and
auriculotemporal nn.
(from CN V3)
Internal carotid a.
Internal jugular v.
with CN IX, X, and XI
Longus capitis
Mastoid air cells
Vertebral a.
Sigmoid sinus
Medulla oblongata
Cerebellum,
posterior lobe
Falx cerebri around
superior sagittal sinus
Occipital
bone
Fourth
ventricle
Fig. 46.19 Transverse MRI
through the neck
Inferior view. (Reproduced from
Moeller TB, Reif E. Pocket Atlas
of Sectional Anatomy, Vol 1,
4th ed. New York, NY: Thieme;
2014.)
Thyroid cartilage
Sternohyoid and
thyrohyoid
Anterior jugular vv.
Platysma
Sternothyroid
Larynx
Thyroid gland
Internal jugular v.
Cricoid cartilage
Common carotid a.
Sternocleidomastoid
with external jugular v.
Scalene mm.
Esophagus
Levator scapulae
Vertebral a. and v.
Spinalis cervicis
Semispinalis cervicis
C7 spinal n. root
Splenius capitis
C6 vertebral body,
C7 posterior arch
C7 spinous
process
Multifidus
Trapezius
669
Head & Neck
Radiographic Anatomy of the Head & Neck (III)
Fig. 46.20 CT scan of temporomandibular joint (TMJ)
Coronal section. (Reproduced
from Moeller TB, Reif E. Atlas of
Sectional Anatomy: The Musculoskeletal System. New York, NY:
Thieme; 2009.)
Temporalis
Temporal lobe
Temporal bone
Articular disk
Zygomatic process
Inferior synovial
cavity
Lateral joint
capsule
Internal carotid a.,
petrous part
Mandible, head
Mandible, ramus
Medial pterygoid
Masseter
Fig. 46.21 CT scan of temporomandibular joint (TMJ)
Sagittal section, mouth closed.
(Reproduced from Moeller TB,
Reif E. Atlas of Sectional
Superior synovial
Anatomy: The Musculocavity
skeletal System. New York,
Articular
disk
NY: Thieme; 2009.)
Articular tubercle
Temporalis
Cerebrum,
temporal lobe
Inferior synovial
cavity
Retrodiskal region
Mandible, head
Lateral pterygoid,
superior head
Lateral pterygoid,
inferior head
External acoustic
meatus
Mandible, neck
Mandible, ramus
Inferior alveolar n.
in mandibular canal
670
Cranial view. In this angiogram note that the right posterior cerebral a.
arises from the internal carotid artery instead of the basilar artery—a
variant. The normal configuration is seen on the left side. (Reproduced
from Moeller TB, Reif E. Pocket Atlas of Sectional Anatomy, Vol 1, 4th
ed. New York, NY: Thieme; 2014.)
Anteromedial frontal br.
of anterior cerebral a.
Ophthalmic a.
Anterior communicating a.
Internal carotid a.
Anterior cerebral a.
Left posterior
communicating a.
Middle cerebral a.
Right posterior cerebral a.
46 Sectional & Radiographic Anatomy
Fig. 46.22 Cranial MR angiography
Superior cerebellar a.
Left posterior cerebral a.
Basilar a.
Temporal a.
Parieto-occipital a.
Fig. 46.23 Dural venous sinus system of the head
Right lateral view. Lateral internal carotid arteriogram, venous phase.
Bridging vv.
Superior sagittal sinus
Internal cerebral v.
Inferior sagittal sinus
Great cerebral v. (of Galen)
Confluence of sinuses
Transverse sinus
Superior petrosal sinus
Sigmoid sinus
Cavernous sinus
Inferior petrosal sinus
Occipital sinus
Internal jugular v.
671
Brain & Nervous System
47 Brain
Nervous System: Overview . . . . . . . . . . . . . . . . . . . . . . . . . . .
Nervous System: Development . . . . . . . . . . . . . . . . . . . . . . .
Brain, Macroscopic Organization . . . . . . . . . . . . . . . . . . . . . .
Diencephalon . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Brainstem & Cerebellum . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Ventricles & CSF Spaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
674
676
678
680
682
684
48 Blood Vessels of the Brain
Veins & Venous Sinuses of the Brain . . . . . . . . . . . . . . . . . . . 686
Arteries of the Brain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 688
49 Functional Systems
Anatomy & Organization of the Spinal Cord. . . . . . . . . . . . . . 690
Sensory & Motor Pathways . . . . . . . . . . . . . . . . . . . . . . . . . . . 692
50 Autonomic Nervous System
Autonomic Nervous System (I): Overview . . . . . . . . . . . . . . . 694
Autonomic Nervous System (II) . . . . . . . . . . . . . . . . . . . . . . . 696
51 Sectional & Radiographic Anatomy
Sectional Anatomy of the Nervous System . . . . . . . . . . . . . . 698
Radiographic Anatomy of the Nervous System . . . . . . . . . . . 700
47
Brain
Brain & Nervous System
Nervous System: Overview
CNS
both white and gray matter
Brain
Spinal cord
Telencephalon
(cerebral hemispheres)
Segments
(only functionally,
not morphologically
displayable)
Diencephalon
Cerebellum
A
Brainstem
Midbrain
(mesencephalon)
C
Pons
Medulla oblongata
B
Fig. 47.1 Morphology of the Central Nervous System
(CNS)
A and B Right side of the brain, medial view; C Section of the spinal
cord, ventral view. A general morphological overview of the entire nervous system is necessary to help with understanding the material that
follows. The CNS is divided into the brain and the spinal cord with the
brain subdivided into the following regions:
• Cerebral hemispheres (telencephalon or endbrain)
• Interbrain (diencephalon)
• Cerebellum
• Brain stem composed of the midbrain (mesencephalon), pons (bridge)
and medulla oblongata
In contrast, the other part of the CNS, the spinal cord appears morphologically rather as one homogenous structure. In terms of its functions,
however, the spinal cord can also be divided into segments.
The division of gray and white matter is clearly visible:
• Gray matter: centrally located, butterfly-shaped structure
• White matter: substance that surrounds the “butterfly”
Fig. 47.2 Axes of the nervous system and directional
terms
The same planes, axes and directional terms apply for both the entire
body and the PNS. However, with the CNS, one differentiates between
two axes:
Parietal/
dorsal superior
Cranial/oral
Frontal/cranial/
oral/rostral anterior
②
Note: In order to avoid topographical misunderstandings, the following
directional terms for axis No. 2 (Forel axis) are used:
Basal/
ventral inferior
Ventral
①
Caudal
674
Occipital/
caudal posterior
• Axis No. 1: Meynert axis: It corresponds to the axes of the body and
is used to designate locations in the spinal cord, brainstem (truncus
encephali) and cerebellum.
• Axis No. 2: Forel axis. It turns horizontally through the diencephalon
and telencephalon and forms an 80° angle to axis 1. As a result, the
diencephalon and telencephalon lie “face down”.
Dorsal
• basal instead of ventral
• parietal instead of dorsal
• frontal and oral/rostral respectively instead of cranial
• occipital instead of caudal
Gray matter
White matter
47 Brain
PNS
②
Ganglia
①
Spinal ganglion
(dorsal root ganglion)
Nerves
Spinal nerves
A
① anterior root
② posterior root
Cranial nerves
Ganglion of cranial nerve
“False
cranial nerves”
(cranial nerves I and II)
B
“True
cranial nerves”
(cranial nerves III-XII)
Splanchnic nerves
(can be functionally and
topographically further
divised, see pp. 280–281)
Autonomic ganglia
(these ganglia can be
functionally and
topographically further
divised, see pp. 280–281)
C
Fig. 47.3 Morphology of the peripheral nervous system
A Segment of the spinal cord, ventral view; B Base of the brain; C view of
sympathetic ganglia and nerves located anterior to the sacrum.
The nerves and ganglia forming the peripheral nervous system are generally named for the part of the CNS with which they communicate:
• Spinal nerves (connect the periphery of the body with the spinal cord.
Usually 31 or 32 pairs. Spinal nerves (except those related to vertebral levels T1 to T11 or T12) generally have their anterior rami form
plexuses for reasons of functionality.
• Cranial nerves (connect the periphery of the body to the brain). 12
pairs.
Nerve cells found within ganglia (in the PNS) can be classified based
on their affiliation with a particular functional division of the nervous
system:
• Sensory neurons can be found within either division of the nervous
system. In the PNS, sensory neurons are found within the sensory
(dorsal root) ganglia on the posterior (dorsal) root of the spinal nerve.
In the CNS, sensory neurons are found within the sensory nuclei associated with the appropriate cranial nerves that contain sensory fibers.
• Ganglia of the autonomic nervous system contain postganglionic
sympathetic and parasympathetic neurons that control the organs of
the body. Autonomic ganglia are associated with splanchnic nerves
that take vasomotor fibers to the viscera. The autonomic nervous
system also demonstrates characteristic plexus formation.
Note: The distinction of sensory nerves in the CNS applies except for a
few special cases. For instance, cranial nerves I (olfactory) and II (optic)
are not true nerves but parts of the telencephalon or diencephalon,
which clearly makes them part of the CNS. For historical reasons, they
have been called “nerves”, which is systematically false. These “bogus”
cranial nerves (colored red on the brain in the figure above) are often
contrasted with the 10 true cranial nerves (colored yellow on this figure),
which are clearly part of the PNS. In the interest of clarity, further details
are located within each region throughout the atlas.
675
Brain & Nervous System
Nervous System: Development
Fig. 47.4 Central and peripheral
nervous systems
The CNS consists of the brain and spinal cord, which constitute
a functional unit. The PNS consists of the nerves emerging from
the brain and spinal cord (cranial and spinal nerves, respectively).
Nerves emerging from the spinal canal after the end of the spinal
cord, form the cauda equina (see p. 41)
Cranial nn.
Brain
Fig. 47.5 Gray and white matter in the CNS
Nerve cell bodies appear gray in gross inspection, whereas nerve cell
processes (axons) and their insulating myelin sheaths appear white.
Spinal nn.
White
matter
Cerebral
cortex
Spinal
cord
Gray
matter
Basal
ganglia
A
Coronal section through the brain.
Cauda
equina
Gray
matter
White
matter
B
Transverse section through the spinal cord.
Table 47.1
Neural
tube
Development of the brain
Primary vesicle
Region
Structure
Prosencephalon
(forebrain)
Telencephalon (cerebrum)
Cerebral cortex, white matter, and basal ganglia
Diencephalon
Epithalamus (pineal), dorsal thalamus, subthalamus, and hypothalamus
Mesencephalon (midbrain)*
Rhombencephalon
(hindbrain)
Metencephalon
Myelencephalon
Tectum, tegmentum, and cerebral peduncles
Cerebellum
Pons*
Medulla oblongata*
Cerebellar cortex, nuclei, and peduncles
Nuclei and fiber tracts
* The mesencephalon, pons, and medulla oblongata are collectively known as the brainstem.
676
Fig. 47.6 Embryonic development of the brain
Left lateral view.
47 Brain
Cervical flexure
Medulla
oblongata
Cranial
flexure
Insula
Pons
Pons
Optic
cup
Medulla
oblongata
A
Start of 2nd month.
C3rd month of development.
Telodiencephalic
sulcus
Insula
Hypophysis
primordium
Eye
Mammillary
tubercle
Olfactory bulb
Pons
Medulla
oblongata
D7th month.
B
End of 2nd month.
Fig. 47.7 Adult brain
See Fig. 47.10 for lobes of the cerebrum. CN, cranial nerve.
Frontal
lobe
Central sulcus
Precentral
gyrus
Postcentral
gyrus
Longitudinal cerebral
fissure
Parietal
lobe
Optic chiasm
Frontal
lobe
Optic n. (CN II)
Hypophysis
Occipital
lobe
Lateral sulcus
Temporal
lobe
Temporal
lobe
Pons
Pons
Cerebellum
Medulla
oblongata
Medulla
oblongata
Left lateral view.
A
Cerebellum
Cingulate gyrus
Cervical spinal cord
B
Basal view.
Pineal gland
Corpus
callosum
Mesencephalon
Thalamus
Occipital
lobe
Hypothalamus
Hypophysis
C
Right hemisphere,
midsagittal section.
Pons
Medulla oblongata
Cerebellum
677
Brain & Nervous System
Brain, Macroscopic Organization
Fig. 47.8 Cerebrum
surface anatomy of the cerebrum can be divided macroscopically into 4
lobes: frontal, parietal, temporal, and occipital. The surface contours of
the cerebrum are defined by convolutions (gyri) and depressions (sulci).
Left lateral view. The cerebrum is part of the anterior subdivision of the
embryonic forebrain (telencephalon)—the part of the adult forebrain
that includes the cerebral hemispheres and associated structures. The
Superior frontal gyrus
Precentral
gyrus
Central
sulcus
Postcentral
gyrus
Middle frontal gyrus
Superior parietal lobule
Intraparietal sulcus
Superior frontal sulcus
Inferior frontal sulcus
Inferior
frontal
gyrus
Supramarginal gyrus
Opercular part
Triangular part
Orbital part
Parietooccipital
sulcus
Frontal pole
Occipital pole
Anterior ramus
Lateral sulcus
(of Sylvius)
Ascending ramus
Posterior ramus
Temporal pole
Superior temporal gyrus
Inferior Inferior
temporal temporal
sulcus
gyrus
Superior temporal sulcus
Preoccipital Transverse
occipital
notch
sulcus
Middle
temporal gyri
Parietal
operculum
Fig. 47.9 Insular lobe
Lateral view of the retracted left cerebral
hemisphere. Part of the cerebral cortex sinks
below the surface during development forming the insula (or insular lobe). Those portions
of the cerebral cortex that overlie this deeper
cortical region are called opercula (“little
lids”).
Frontal
operculum
Insular lobe
(= insula)
678
Inferior
parietal lobule
Angular gyrus
Temporal
operculum
Calcarine
sulcus
Fig. 47.10 Lobes in the cerebral hemispheres
The isocortex also may be functionally divided into association areas (lobes).
Parietal lobe
Temporal lobe
47 Brain
Insula
Central sulcus
Frontal lobe
Occipital lobe
Insular lobe (insula)
B
Lateral view of the retracted
left cerebral hemisphere.
Limbic lobe (limbus)
Frontal pole
A
Left hemisphere, lateral view.
Lateral sulcus
Cingulate gyrus
Olfactory n. (CN I)
Corpus callosum
Parietooccipital
sulcus
Optic n. (CN II)
Hypophysis
Mammillary body
Septum
pellucidum
Mesencephalon
Fornix
DBasal view with the brainstem
removed.
C
Right hemisphere, medial view.
Occipital pole
Longitudinal
cerebral fissure
Fig. 47.11 Midsagittal section of the brain showing the
medial surface of the right hemisphere
The brain has been split along the longitudinal cerebral fissure.
Medial frontal
gyrus
Cingulate
sulcus
Paracentral
Paracentral lobule
Central
sulcus
sulcus
Marginal sulcus
Cingulate gyrus
Corpus callosum
Sulcus of
corpus callosum
Precuneus
Choroid plexus
Parieto-occipital
sulcus
Interventricular
foramen
Cuneus
Calcarine
sulcus
Subcallosal gyrus
Third
ventricle
Interthalamic
adhesion
Septum
pellucidum
679
Brain & Nervous System
Diencephalon
The diencephalon is the posterior subdivision of the forebrain—the
part of the adult forebrain that includes the thalamus and associated
structures.
Fig. 47.12 Diencephalon
Right hemisphere, midsagittal
section, medial view. The major
components of the diencephalon
are the thalamus, hypothalamus,
and hypophysis (anterior lobe).
The diencephalon is located
below the corpus callosum, part
of the cerebrum, and above the
midbrain. The thalamus makes
up four-fifths of the diencephalon
but the only parts that can be
seen externally are the hypothalamus (seen on the basal aspect
of the brain) and portions of the
epithalamus. In the adult brain
the diencephalon is involved
in endocrine functioning and
autonomic coordination of the
pineal, neurohypophysis, and hypothalamus. It also acts as a relay
station for sensory information
and somatic motor control via the
thalamus.
Hypothalamic sulcus
(ventral diencephalic sulcus) Thalamus
Corpus
callosum
Choroid
plexus
Fornix
Interthalamic
adhesion
Stria medullaris
thalami
Pineal
(epiphysis)
Anterior
commissure
Preoptic
area
Hypothalamus
Supraoptic
recess
Infundibular
recess
Cerebellum
Infundibulum
Anterior lobe
(adenohypophysis)
Tuber
Posterior lobe
(neurohypophysis) cinereum
Hypophysis
3rd ventricle
Mammillary
body
Cerebral Tegmentum Cerebral Quadrigeminal
aqueduct
plate
peduncle
Mesencephalon
Fig. 47.13 Arrangement of the
diencephalon around the third
ventricle
Oblique transverse section through the
telecephalon with the corpus callosum,
fornix, and choroid plexus removed, posterior view. This figure clearly illustrates that
the lateral wall of the third ventricle forms
the medial boundary of the diencephalon.
680
v.
Fig. 47.14 The diencephalon and
brainstem
Corpus
callosum
Lateral
geniculate
body
47 Brain
Left lateral view. The cerebral hemispheres
have been removed from around the thalamus. The cerebellum has also been removed.
The parts of the diencephalon visible in this
dissection are the thalamus, the lateral geniculate body, and the optic tract. The latter two
are components of the visual pathway. This
dissection illustrates the role the diencephalon plays in linking the underlying brainstem
to the overlying cerebral hemispheres.
Thalamus
Pulvinar
Pineal
Optic tract
Superior
colliculus
Optic nerve
Inferior
colliculus
Infundibulum
Quadrigeminal
plate
Mammillary
body
Cerebral
peduncle
Brachium of
inferior colliculus
Cerebellum
Fig. 47.15 Location of the diencephalon in the adult brain
Basal view of the brain (brainstem has been sectioned at the level of the
pons). The structures that can be identified in this view represent those
parts of the diencephalon situated on the basal surface of the brain. This
view also demonstrates how the optic tract winds around the cerebral
peduncles. The expansion of the telencephalon during development limits
the number of structures of the diencephalon visible on the under­surface
of the brain. They are:
• Optic nerve
• Optic chiasm
• Optic tract
• Tuber cinerum with the
infundibulum
• Mammilary bodies
• Lateral geniculate body
• Neurohypophysis
Optic nerve
Optic chiasm
Infundibulum
Tuber cinereum
Hypothalamus
Mammillary body
Optic tract
Cerebral peduncle
Substantia nigra
Red nucleus
Lateral
geniculate
body
Cerebral aqueduct
681
Brain & Nervous System
Brainstem & Cerebellum
he stalk-like region of the brain connecting the cerebral hemispheres
T
to the cerebellum and spinal cord consists of the diencephalon (thalamus and associated structures) and the brainstem—composed of the
mesencephalon or midbrain, pons and medulla oblongata moving
sequentially caudal. Fiber bundles pass through this region from the
spinal cord on their way to and from the cerebrum; thick fiber bundles
pass contralaterally from the cerebrum into the cerebellar hemispheres;
and 10 of the 12 cranial nerves are associated with the brainstem.
Corpus callosum
Fig. 47.16 Diencephalon, brainstem, and cerebellum
Choroid plexus
Left lateral view.
Pineal
Tectal
Lateral geniculate
body
Thalamus
Pulvinar
Anterior lobe
Hypothalamus
Optic chiasm
Primary fissure
Infundibulum
Mammillary body
Infundibulum
Horizontal
fissure
Posterior
lobe
Cerebral
peduncle
Pons
Horizontal
fissure
Adenohypophysis
Neurohypophysis
Superior
medullary velum
Posterolateral fissure
Tonsil
Flocculus
Medulla oblongata
Pyramid
A
Isolated structures.
Fig. 47.17 Cerebellum
Anterior
lobe
Central
lobule
Primary
fissure
Lingula
Anterior
commissure
Quadrigeminal plate
Optic n.
(CN II)
Primary
fissure
Culmen
Choroid
plexus
Nodule
B
Midsagittal section.
Tracts of afferent (sensory) or efferent (motor) axons enter or leave the cerebellum
through cerebellar peduncles. Afferent axons
originate in the spinal cord, vestibular organs,
inferior olive, and pons. Efferent axons originate in the cerebellar nuclei.
Lateral parts
Vermis
Superior
cerebellar
peduncle
Folium of vermis
Inferior semilunar
lobule
Superior medullary Central
lobule
velum
Superior cerebellar
peduncle
Middle
cerebellar
peduncle
Horizontal
fissure
Anterior spinocerebellar tract
Middle cerebellar
peduncle
Trigeminal n.
(CN V)
Vestibulocochlear
n. (CN VIII)
Facial n. (CN VII)
Lingula
4th
ventricle
Inferior
cerebellar
peduncle
Central tegmental
tract
Olive
Nodule
Flocculus
Horizontal
fissure
Uvula
vermis
Flocculonodular lobe
Intermediate parts
Pyramid Vallecula
of vermis
B
Anterior view.
4th
ventricle
Fig. 47.18 Cerebellar peduncles
Quadrangular
lobule
Simple lobule
Posterior
lobe
A
Superior view.
Prebiventral
fissure
Median part
Superior semilunar
lobule
682
Fornix
Tonsil
Peduncle
of flocculus
Inferior
cerebellar
peduncle
Fig. 47.19 Brainstem
Oculomotor n.
(CN III)
Interpeduncular
fossa
Cerebral
peduncle
47 Brain
The brainstem is the site of emergence and entry of the 10 pairs of
true cranial nerves (CN III–XII). See pp. 560–561 for an overview of the
cranial nerves and their nuclei.
Pons
Diencephalon
Trigeminal n.
(CN V)
Cerebral
aqueduct
Mesencephalon
Cerebellum
Hypophysis
Pons
4th
ventricle
Rhomboid
fossa
Medulla
oblongata
Abducent n.
(CN VI)
Facial n.
(CN VII)
Nervus
intermedius
Vestibulocochlear n.
(CN VIII)
Olive
Glossopharyngeal n.
(CN IX)
A
Levels of the brainstem.
Pyramid of
medulla
oblongata
Vagus n. (CN X)
Hypoglossal n.
(CN XII)
Cerebral
peduncle
Brachium of
inferior colliculus
Accessory n.
(CN XI)
Superior
colliculus
Inferior
colliculus
Pons
CN V,
motor
root
Anterior
median fissure
C1 spinal n.,
anterior root
Decussation
of pyramids
Tectal
plate
B
Anterior view.
Trochlear n. (CN IV)
Superior
cerebellar
peduncle
CN V,
sensory
root
Middle
cerebellar
peduncle
Inferior
cerebellar
peduncle
CN VIII
CN VII
Lateral
aperture
CN VI
CN X
Nervus
intermedius
CN IX
CN XI
CN XII
C
Left lateral view.
Brachium of
superior colliculus
Anterolateral
sulcus
Posterolateral
sulcus
Brachium of
inferior colliculus
Superior
and inferior
colliculi
Superior
medullary
velum
Superior
cerebellar
peduncle
CN IV
CN V
Medial
eminence
Middle
cerebellar
peduncle
Inferior
cerebellar
peduncle
Rhomboid
fossa
Vestibular
area
Olive
C1 spinal n.,
ventral root
Pineal
Facial
colliculus
Striae
medullaris
CN XII, trigone
Taenia
cinerea
CN X, trigone
Tubercle of
nucleus cuneatus
Tubercle of
nucleus gracilis
DPosterior view.
683
Brain & Nervous System
Ventricles & CSF Spaces
Fig. 47.20 Circulation of cerebrospinal fluid (CSF)
The brain and spinal cord are suspended in CSF. Produced continually in
the choroid plexus, CSF occupies the subarachnoid space and ventricles
of the brain and drains through arachnoid granulations into the dural
Arachnoid
granulations
venous sinus system (primarily the superior sagittal sinus) of the cranial
cavity. Smaller amounts drain along proximal portions of the spinal
nerves into venous plexuses or lymphatic pathways.
Choroid plexus
(lateral ventricle)
Choroid plexus
(3rd ventricle)
Superior
sagittal sinus
Ambient cistern
Interhemispheric
cistern
Straight sinus
Interventricular
foramen
Cerebral
aqueduct
Confluence
of sinuses
Cistern of lamina
terminalis
Basal
cistern
Vermian cistern
Choroid plexus
(4th ventricle)
Chiasmatic
cistern
Cerebellomedullary cistern
(cisterna magna)
Interpeduncular
cistern
Pontomedullary
cistern
Median
aperture
Central canal
of the spinal cord
Spinal cord
Vertebral
venous plexus
CSF flow
Subarachnoid space
Ventricle
Vein or venous sinus
Choroid plexus
684
Subarachnoid
space
Endoneural
space
Spinal n.
Fig. 47.21 Ventricular system
3rd ventricle
47 Brain
The ventricular system is a continuation of the central spinal canal into
the brain. Cast specimens are used to demonstrate the connections
between the four ventricular cavities.
Lateral
ventricle,
left
Anterior
horn
Right lateral
ventricle
Inferior
horn
Cerebral
aqueduct
Left lateral
ventricle
Collateral
trigone
Lateral recess
Posterior
horn
B
Lateral ventricles in
transverse section.
4th ventricle
Anterior horn
A
Superior view.
Collateral
trigone
Lateral
ventricle
Posterior horn
Interventricular
foramen
Inferior horn
3rd
ventricle
4th
ventricle
Cerebral
aqueduct
Lateral
ventricle
Lateral recess
C
Left lateral ventricle in
parasagittal section.
Central canal
DLeft lateral view.
Fig. 47.22 Ventricular system in situ
Left lateral view.
Lateral ventricle
Interthalamic Fornix
(central part)
adhesion
Interventricular
foramen
Suprapineal
recess
Pineal recess
Pineal gland
3rd ventricle
Cerebral
aqueduct
Corpus
callosum
Anterior Interventricular Septum
foramen
pellucidum
commissure
Fornix
Corpus
callosum
Lateral
ventricle
(anterior
horn)
Collateral
trigone
Supraoptic recess
Optic chiasm
Lateral
ventricle
(posterior
horn)
Infundibular
recess
Hypophysis
Quadrigeminal
plate
Hypothalamus
Infundibulum
Cerebral peduncle
(crus cerebri)
Pons
Medulla oblongata
A
3rd and 4th ventricles in midsagittal section.
Lateral ventricle
(inferior horn)
4th ventricle
Lateral recess,
ends as a lateral aperture
of 4th ventricle
Central canal
Median aperture
of 4th ventricle
B
Ventricular system with neighboring structures.
685
48
Blood Vessels of the Brain
Brain & Nervous System
Veins & Venous Sinuses of the Brain
Additional information on the venous sinus system and dural folds of
the cranial cavity can be found on pp. 590–593.
Fig. 48.1 Superficial cerebral veins
Bridging vv.
Superior
anastomotic v.
Superior
sagittal sinus
Superior
cerebral vv.
Inferior
anastomotic v.
Medial and
lateral
superior
cerebellar vv.
Superficial
middle cerebral v.
Confluence
of sinuses
Superior and inferior
petrosal sinuses
Transverse sinus
Occipital sinus
Petrosal v.
Sigmoid sinus
Internal jugular v.
A
Left hemisphere, lateral view.
Superior
sagittal
sinus
Thalamostriate v.
Superior
cerebral vv.
Inferior
sagittal sinus
Anterior v.
of septum
pellucidum
Internal
occipital v.
Great
cerebral v.
Straight sinus
Anterior
cerebral v.
Confluence of
sinuses
Internal
cerebral v.
Transverse sinus
Basilar v.
Superior
cerebellar v.
686
Occipital sinus
Posteromedian
medullary v.
B
Right hemisphere, medial view.
Fig. 48.2 Basal cerebral venous system
Basal (inferior) view.
Anterior
communicating v.
Anterior
cerebral v.
Peduncular v.
Deep
middle
cerebral v.
Inferior
choroidal v.
48 Blood Vessels of the Brain
Superficial
middle
cerebral v.
Basilar v.
Internal
cerebral v.
Posterior
venous
confluence
Great
cerebral v.
Fig. 48.3 Veins of the brainstem
Basal (inferior) view.
Basilar v.
Interpeduncular v.
Pontomesencephalic v.
Trigeminal n.
(CN V)
Superior petrosal v.
Superior cerebellar vv.
Transverse
pontine vv.
Anterolateral and
anteromedian
pontine v.
Transverse
medullary vv.
Posteromedian
medullary v.
687
Brain & Nervous System
Arteries of the Brain
Fig. 48.4 Internal carotid artery
Left lateral view. See p. 582 for details of the
internal carotid artery.
Posterior
communicating a.
Posterior
cerebral a.
Cerebral
part
Fig. 48.5 Arteries of the brainstem
and cerebellum
Petrous
part
Left lateral view.
Internal
carotid a.
Posterior
cerebral a.
Basilar a.
Superior
cerebellar a.
Cervical
part
CN III
External
carotid a.
Common
carotid a.
Vertebral a.
Labyrinthine a.
Aortic arch
Left
subclavian a.
Fig. 48.6 Arteries of the brain
CN V
Basilar a.
Anteroinferior
cerebellar a.
CN VI
Vertebral a.
Posteroinferior
cerebellar a.
Basal (inferior) view.
Postcommunicating
part (A2)
Anterior
cerebral a.
Internal carotid a.
Precommunicating
part (A1)
Postcommunicating
part (P2)
Posterior
cerebral a.
Precommunicating
part (P1)
Lateral occipital a.
(P3)
Anterior inferior
cerebellar a.
Posterior inferior
cerebellar a.
Vertebral a.
688
Anterior
communicating a.
Sphenoidal
part (M1)
Insular
part (M2)
Middle
cerebral a.
Posterior
communicating a.
Anterior
choroidal a.
Pontine aa.
Superior cerebellar a.
Basilar a.
Medial occipital a. (P4)
Anterior spinal a.
Fig. 48.7 Cerebral arteries
A. of central sulcus
A. of
postcentral sulcus
Fig. 48.8 Cerebral arteries: Distribution
areas
Posterior
parietal a.
The central gray and white matter have a complex
blood supply (yellow) that includes the anterior
choroidal artery.
Temporooccipital br.
Corpus
Lateral
callosum
ventricle
Thalamus
Prefrontal a.
Lateral
frontobasal a.
Anterior,
middle, and
posterior
temporal brs.
Caudate
nucleus
Insula
Cortical margin
48 Blood Vessels of the Brain
A. of
precentral sulcus
A
Middle cerebral artery. Left hemisphere,
lateral view.
Aa. of precentral, central,
and postcentral sulci
Claustrum
Internal
capsule
Hippocampus
Globus
pallidus
Posterior
parietal a.,
angular
gyral br.
Middle
cerebral a.
Anterior cerebral a.
Middle cerebral a.
Posterior cerebral a.
Left hemisphere, lateral view.
A
Temporooccipital br.
Lateral
frontobasal a.
Cortical margin
Anterior, middle, and
posterior temporal brs.
Corpus
callosum
Septum
pellucidum
B
Middle cerebral artery. Left lateral view
with the lateral sulcus retracted.
Pericallosal a.
Cingular br.
Putamen
Precuneal brs.
Parietooccipital brs.
Callosomarginal a.
Anterior
commissure
Dorsal
callosal br.
Polar
frontal a.
Optic
chiasm
3rd
ventricle
Lateral Thalamus
ventricle
Cerebral
aqueduct
Pineal
(epiphysis)
B
Right hemisphere, medial view.
Parietooccipital br.
Anterior
cerebral a.
Posterior
cerebral a.
Anterior
temporal a. (P3)
Middle and posterior
temporal brs.
Medial
occipital
a. (P4)
C
Anterior and posterior cerebral arteries.
Right hemisphere, medial view.
689
49
Functional Systems
Brain & Nervous System
Anatomy & Organization of the Spinal Cord
Fig. 49.1 Anatomy of a spinal cord segment
Three dimensional representation, oblique anterior view from upper
left. The gray matter of the spinal cord is found internally, surrounding
the central canal in an H-shaped, or butterfly-like, configuration. This
is the reverse of what was seen in the brain where the gray matter was
Gray commissure
on the external aspect in a cortical configuration. The primary function
of the spinal cord is to conduct impulses to and from the brain. To facilitate this, both gray and white matter are organized into longitudinal
groupings.
Posterior
column
Posterior
median sulcus
Posterior intermediate sulcus
Posterior gray horn
Central canal
Posterior rootlets
Lateral column
Sensory ganglion
Posterior root
Spinal nerve
Intermediolateral
gray horn
Anterior root
Anterior
gray horn
Anterior rootlets
Anterior
medial fissure
Anterior
column
Anterolateral sulcus
Fig. 49.3 Innervation of muscles
Fig. 49.2 Organization of the gray matter
Left oblique anterosuperior view. The gray matter of the spinal cord
is divided into three columns (horns).
• Anterior column (horn): contains motor neurons
• Lateral column (horn): contains sympathetic or parasympathetic
(visceromotor) neurons in selected regions
• Posterior column (horn): contains sensory neurons
Motor neurons that innervate specific muscles are arranged into
vertical columns in the anterior horn of gray matter, the columns
themselves can be called nuclei, in a fashion similar to that seen in
brainstem motor nuclei. Most muscles (intersegmental muscles)
receive innervation from numerous motor nuclei spanning several spinal cord segments. Monosegmental (or indicator) muscles have their
motor neurons located entirely within a single spinal cord segment.
Nuclear
column
Sensory (blue) and motor (red) neurons within these columns are
clustered in nuclei according to function.
Anterior
root
Posterior
horn (sensory)
Peripheral n.
Plexus
Lateral horn
(visceromotor)
Sensory
nuclei
Anterior horn
(motor)
Motor
nuclei
Columns
690
Nuclei
Spinal cord
segment
Monosegmental
muscle innervation
Multisegmental
muscle
innervation
Fig. 49.4 Organization of the white matter
Posterior
funiculus
Ascending tracts
(sensory)
Lateral
funiculus
Interneuron
Upper motor
neuron (in the
motor cortex)
Neuron in the
sensory cortex
Tertiary sensory
neuron
Secondary sensory
neuron
Anterior
funiculus
49 Functional Systems
Left oblique anterosuperior view. The gray matter columns partition the
white matter analogously into anterior, lateral, and posterior columns
or funiculi. The white matter of the spinal cord contains ascending and
descending tracts which are the CNS equivalent of peripheral nerves.
Descending
tracts
(motor)
Funiculi
Tracts
Fig. 49.5 Overview of sensorimotor integration
Schematic illustrates the pathway of incoming primary sensory
neuron impulses, the axon of which ascends to synapse with
the secondary and tertiary sensory neurons in the brainstem
and cerebrum ending in a synapse on a neuron in the sensory
cortex. An interneuron links this with an upper motor neuron
in the motor cortex which then descends through the white
matter funiculi of the spinal cord to a motor neuron, which then
synapses with a lower motor neuron, the axon of which passes
out the spinal nerve to the effector organ.
Fig. 49.6 Principle intrinsic fascicles of the spinal cord
(shaded yellow)
Left oblique anterosuperior view. The majority of muscles have a multi­
segmental mode of innervaton that necessitates axons to ascend/descend
multiple spinal cord segments to coordinate spinal reflexes. The neurons of
these axons originate from interneurons in the gray matter forming intrinsic
reflex pathways of the spinal cord. These axons are collected into intrinsic
fascicles which are arranged chiefly around the gray matter. These bundles
make up the intrinsic circuits of the spinal cord.
Interfascicular fasciculus
(only in cervical cord)
Longitudinal
fasciculus of
posterior column
Lateral
fasciculus
proprius
Sulcomarginal
fasciculus
Septomarginal
fasciculus (only in
thoracic cord)
Philippe-Gombault
triangle (only in
sacral cord)
Motor interneuron
Lower motor neuron
Primary sensory
neuron
Fig. 49.7 Intrinsic circuits of the spinal cord
Sensory neurons are shown in blue, motor neurons in red. The
neurons of the spinal reflex circuits are in black. These chains
of interneurons, which are entirely contained within the spinal
cord, comprise the intrinsic circuits of the cord. The axons of
these intrinsic circuits pass to adjacent segments in intrinsic
fascicles located along the edge of the gray matter.
Spinal ganglion
α-motor
neuron
Intercalated cell
Projection
neuron
Commissural
cell
Association
cell
α-motor
neuron
691
Brain & Nervous System
Sensory & Motor Pathways
Fig. 49.8 Sensory pathways
(ascending tracts)
Sensory cortex
(postcentral gyrus)
3rd neurons
Thalamus
Accessory
nucleus
cuneatus
Nucleus
cuneatus
2nd neuron
②
Cuneocerebellar fibers
Nucleus
gracilis
Medial
lemniscus
④
Anterolateral
system (spinothalamic tracts)
②
③
①
Unconscious
proprioception
Position sense,
conscious proprioception,
vibration, touch
*
⑤
Pressure, touch
Pain, temperature
H G
Sensory ganglion
of spinal n.
(with 1st neurons)
2nd neurons
F
D
S
α-motor neuron
*The fasciculi cuneatus and gracilis convey information from the upper and
lower limbs, respectively. At this spinal cord level, only the fasciculus cuneatus
is present.
A
Table 49.1
Sensory pathways (ascending tracts) of the spinal cord
Tract
Function
Neurons
①
Anterior spinothalamic tract
Anterior
funiculus
Pathway for crude touch and pressure sensation
②
Lateral spinothalamic tract
Anterior and
lateral funiculi
Pathway for pain, temperature, tickle, itch, and sexual sensation
1st afferent neurons located in spinal ganglia;
contain 2nd neurons and cross in the anterior
commissure
③
Anterior spinocerebellar tract
④
Posterior spinocerebellar tract
Lateral
funiculus
Pathway for unconscious coordination of motor activities (unconscious
proprioception, automatic processes, e.g., jogging, riding a bike) to the
cerebellum
Projection (2nd) neurons receive proprioceptive
signals from 1st afferent fibers originating at the
1st neurons of spinal ganglia
⑤
Fasciculus
cuneatus
Posterior
funiculus
Pathway for position sense (conscious
proprioception) and fine cutaneous
sensation (touch, vibration,
fine pressure sense, two-point
discrimination)
⑥
692
Location
Fasciculus
gracilis
Conveys information from upper
limb (not present below T3)
Conveys information from lower
limb
Cell bodies of 1st neuron located in spinal
ganglion; pass uncrossed to the dorsal column
nuclei
Descending tracts from brainstem
(extrapyramidal motor system)
Precentral gyrus
(primary motor
cortex)
Leg
Arm
Postcentral
gyrus
(primary
somatosensory
cortex)
Face
Fig. 49.9 Motor pathways
(descending tracts)
Supplementary
motor cortex,
premotor cortex
Tegmental nucleus
Corticospinal
tracts
Corticospinal
fibers
Corticonuclear
fibers
49 Functional Systems
Corticospinal tracts
(pyramidal tract)
Red nucleus
Substantia
nigra
From
cerebellum
Pyramidal
tract
Ventral
intermedius
nucleus
CN VII
Inferior
olive
CN XII
Pyramid
Spinal n., posterior root
Pyramidal
decussation
②
③
⑦
②
Spinal n.,
anterior root
①
Table 49.2
①
Function
①
Descending tracts
from the brainstem
(Extrapyramidal
motor system)
⑥
④
Descending tracts of the spinal cord
Tract
Corticospinal tract
(pyramidal tract)
α-motor ⑤
neuron (with
interneurons)
Anterior corticospinal tract
②
Lateral corticospinal tract
③
Rubrospinal tract
④
Reticulospinal tract
⑤
Vestibulospinal tract
⑥
Tectospinal tract
⑦
Olivospinal tract
Most important
pathway for
voluntary motor
function
Originates in the motor cortex
Corticonuclear fibers to motor nuclei
of cranial nerves
Corticospinal fibers to motor cells in
anterior horn of the spinal cord
Corticoreticular fibers to nuclei of the
reticular formation
S
D
F
Pathway for automatic and learned motor processes
(e.g., walking, running, cycling)
A
H
G
693
50
Autonomic Nervous System
Brain & Nervous System
Autonomic Nervous System (I): Overview
Fig. 50.1 Autonomic nervous system
Except in the head, parasympathetic preganglionic neurons synapse in
ganglia in the wall of the target organ. Short postganglioinc parasympathetic neurons then innervate the organ. In the head there are four
parasympathetic ganglia: ciliary, pterygopalatine, submandibular, and
otic, which are associated with cranial nerves III, VII, and IX, respectively. These four ganglia are responsible for distributing fibers to
smooth muscle within the eye and to the salivary glands and glands of
the nasal cavity, paranasal sinuses, hard and soft palate, and pharynx.
Both sympathetic and parasympathetic preganglionic neurons secrete
acetylcholine, which acts upon nicotinic receptors in the ganglia.
Sympathetic postganglionic neurons secrete norepinephrine, which
acts upon adrenoceptors (α or β) in target tissues. Parasympathetic
postganglionic neurons secrete acetylcholine, which acts upon
muscarinic receptors in target tissues.
The autonomic nervous system is the part of the peripheral nervous
system that innervates smooth muscle, cardiac muscle, and glands. It is
subdivided into the sympathetic (red) and the parasympathetic (blue)
nervous systems, which often act in antagonistic fashion to regulate
blood flow, secretions, and organ function. Both the sympathetic and
parasympathetic nervous systems have a two-neuron pathway, which is
under central nervous system control via an upper motor neuron with
its cell body in the hypothalamus. In the sympathetic system, the
preganglionic neuron synapses within the ganglia of the sympathetic
trunk (paired, one on each side of vertebral column) or on one of the
unpaired prevertebral ganglia located at the base of the artery for
which the ganglion was named (celiac, superior and inferior mesenteric). Sympathetic postganglionic neurons then either reenter spinal
nerves via gray rami communicans and are distributed to their target
structure or they reach their target structure by travelling with arteries.
Parasympathetic
ganglia (in the head)
Sympathetic nervous system
Eye
Superior
cervical
ganglion
Parasympathetic nervous system
CN VII
CN III
Lacrimal and
salivary glands
Parasympathetic ganglia
(within the walls of organs)
Sympathetic trunk
Stellate ganglion*
Cranial part:
brainstem
with parasympathetic
nuclei
CN IX
Cranial vessels
CN X
Heart
T1
T2
T3
T4
T5
T6
Greater
splanchnic n.
Celiac
ganglion
T7
T8
Lung
Stomach
Liver
Pancreas
T9
Kidney
T 10
T 11
Intestine
T 12
L1
Superior mesenteric ganglion
L2
Inferior mesenteric ganglion
L3
Parts of the colon,
rectum
L4
L5
Bladder
Genitalia
A
**Inferior
hypogastric plexus
*Stellate ganglion - inferior cervical
ganglion and T1 sympathetic ganglion
**Minimal sympathetic preganglionic fibers
traveling through the sacral splanchnic
nerves will synapse in the ganglia
located in the inferior hypogastric plexus.
694
Pelvic
splanchnic nn.
S1
S2
S3
S4
S5
Sacral part:
sacral cord
with parasympathetic
nuclei
B
Parasympathetic pathways
Neuron
Location of cell body
Upper motor neuron
Hypothalamus: The cell bodies of parasympathetic upper motor neurons are located in the hypothalamus. Their
axons descend via white matter tracts to synapse with the lower motor neuron in the brainstem and sacral spinal cord
(S2–S4).
Preganglionic neuron (lower motor neuron)
The parasympathetic nervous system is divided into two parts (cranial and sacral), based on the location of the
preganglionic parasympathetic neurons.
Brainstem cranial nerve nuclei: The
axons of these secondary neurons leave
the CNS as the motor root of cranial nn.
III, VII, IX, and X.
Spinal cord (S2–S4): The axons of the sacral parasympathetics originate
from the S2–S4 spinal segments in a region of the spinal cord gray matter
similar to that of the lateral horns where the sympathetic division arises
from. These axons initially travel through the S2–S4 anterior roots before
con-tinuing within the S2–S4 anterior rami. The axons then pass through
pelvic splanchnic nerves that arise from the S2–S4 anterior rami before
reaching the inferior hypogastric plexus, which then distributes the axons
to the pelvic and hindgut structures.
Postganglionic neuron
Cranial nerve parasympathetic ganglia: The parasympathetic cranial nn. of the head each have at least one ganglion:
• CN III: Ciliary ganglion
• CN VII: Pterygopalatine ganglion and submandibular ganglion
• CN IX: Otic ganglion
• CN X: Small unnamed (intramural) ganglia close to target structures
Distribution of postganglionic fibers
Parasympathetic fibers course with other fiber types to their targets. In the head, the postganglionic fibers from
the pterygopalatine ganglion (CN VII) and otic ganglion (CN IX) are distributed via branches of the trigeminal n.
(CN V). Postganglionic fibers from the ciliary ganglion (CN III) course with sympathetic and sensory fibers in the
short ciliary nn. (preganglionic fibers travel with the somatomotor fibers of CN III). In the thorax, abdomen, and
pelvis, preganglionic parasympathetic fibers from CN X and the pelvic splanchnic nn. combine with postganglionic
sympathetic fibers to form plexuses (e.g., cardiac, pulmonary, esophageal).
Table 50.2
50 Autonomic Nervous System
Table 50.1
Sympathetic pathways
Neuron
Location of cell body
Upper motor neuron
Hypothalamus: The cell bodies of sympathetic upper motor neurons are located in the hypothalamus. Their axons
descend via white matter tracts to synapse with the lower motor neuron in the lateral horn of the spinal cord
(T1–L2).
Preganglionic neuron (lower motor neuron)
Intermediolateral gray horn of spinal cord (T1–L2): The lateral horn is the middle portion of the gray matter of
the spinal cord, situated between the anterior and posterior horns. It contains exclusively autonomic (sympathetic)
neurons. The axons of these neurons leave the CNS as the motor root of the spinal nn. and enter the paravertebral
ganglia via the white rami communicans (myelinated).
Preganglionic neurons in paravertebral ganglia
All preganglionic sympathetic neurons enter the sympathetic chain. There they may synapse in a chain ganglion or
ascend or descend to synapse. Preganglionic sympathetic neurons synapse in one of two places, yielding two types
of sympathetic ganglia.
Synapse in the paravertebral ganglia
Pass without synapsing through the sympathetic ganglia.
These fibers travel in the thoracic, lumbar, and sacral
splanchnic nn. to synapse in the prevertebral ganglia.
Postganglionic neuron
Paravertebral ganglia: These ganglia form
the sympathetic nerve trunks that flank the
spinal cord. Postganglionic axons leave the
sympathetic trunk via the gray rami communicans
(unmyelinated).
Prevertebral ganglia: Associated with peripheral plexuses,
which spread along the abdominal aorta. There are three
primary prevertebral ganglia:
• Celiac ganglion
• Superior mesenteric ganglion
• Inferior mesenteric ganglion
Distribution of postganglionic fibers
Postganglionic fibers are distributed in two ways:
1. Spinal nerves: Postganglionic neurons may re-enter the spinal nn. via the gray rami communicans. These
sympathetic neurons induce constriction of blood vessels of the skin and dilate the blood vessels of skeletal
muscles, sweat glands, and arrector pili (muscle fibers attached to hair follicles, “goose bumps”).
2. Arteries and ducts: Nerve plexuses may form along existing structures. Postganglionic sympathetic fibers may
travel with arteries to target structures. Viscera are innervated by this method (e.g., sympathetic innervation
concerning vasoconstriction, bronchial dilatation, glandular secretions, pupillary dilatation, smooth muscle
contraction).
695
Brain & Nervous System
Autonomic Nervous System (II)
Fig. 50.2 Typical spinal nerve
All spinal nerves arising from the spinal cord contain somatic sensory
(or afferent, from body wall) and somatic motor (or efferent, to body
wall) fibers. Sensory fibers come from the posterior (back) region via
the posterior ramus and anterolateral regions of the body wall via the
anterior ramus of the spinal nerve. The somatic sensory fibers approach
the spinal cord via the posterior root. The cell bodies for these fibers lie
in the sensory (spinal/dorsal root) ganglion. They synapse with sensory
Sensory
(spinal)
ganglion
neurons in the posterior horn of gray matter within the spinal cord
sending the majority to the brain for interpretation. Somatic motor
fibers have their neurons in the anterior horn of gray matter and send
their fibers to the spinal n. via the anterior root. This pattern of somatic
innervation occurs in all spinal nerves from C1 through S5, whether
they are involved in a plexus or not.
Posterior
root
Spinal n.
Spinal Cord
Level L2
Posterior
ramus
Anterior
ramus
Anterior
root
Spinal Cord
Level L3
Somatic sensory
(afferent)
Somatic motor
(efferent)
Fig. 50.3 ANS Circuitry
Body wall dermatomes also require sympathetic fibers to contract
smooth muscle and cause glands in the dermatome to secrete.
Preganglionic sympathetic fibers (purple) arise from cell bodies in the
intermediolateral gray horn of the spinal cord. They exit the spinal cord
via the outgoing/efferent (anterior) root—along with the somatic motor
(efferent) fibers—and enter the spinal nerve. The smooth muscle of the
body wall requires innervation by postganglionic sympathetic fibers
so the preganglionic fiber looks for the closest synapse site—the paravertebral sympathetic ganglia—found in a chain-like arrangement on
either side of the vertebral column. Each ganglion is connected to the
spinal n. by communicating branches—the rami communicans. The
white ramus communicans is found most lateral and conveys the preganglionic (myelinated = white) sympathetic fiber to the ganglion.
Once in the paravertebral ganglion one of two things can happen:
a) The preganglionic sympathetic fiber can synapse in the ganglion
and the postganglionic sympathetic fiber (orange) passes along the
gray ramus communicans (unmyelinated) back to the spinal n. Now
postganglionic sympathetic fibers can be distributed to structures
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in the dermatome via the anterior and posterior rami—along with
somatic motor and sensory fibers.
b) The preganglionic fiber can run up or down the sympathetic trunk
to synapse in an upper or lower paravertebral ganglion. This is
especially important as the source of sympathetic innervation is
limited to spinal cord levels T1 to L2. This figure depicts sympathetic
innervation from the last spinal cord segment to contain it (L2)
descending along the sympathetic trunk to the paravertebral
ganglion at L3. It synapses here and the postganglionic sympathetic
fiber exits into the spinal nerve of L3. Note that there is only a gray
ramus communicans at this level as white rami communicans are
input fibers (T1–L2), while the gray are output fibers above and
below T1 and L2. Therefore, there are more gray rami than white
rami. Both anterior and posterior rami now contain postganglionic
sympathetic fibers distributed to the dermatome of L3 along with
the typical somatic sensory and motor fibers of each vertebral level.
Now that the body wall has been supplied with postganglionic
sympathetic innervation, we’ll turn our attention to the viscera. In the
tiny parasympathetic (intramural) ganglion within the wall of the organ.
The postganglionic parasympathetic fibers (light blue) are therefore
extremely short. The remainder of the abdominal and pelvic viscera
receive their parasympathetic supply in a similar fashion but from
preganglionic parasympathetic