Anatomy and Procedures of the
Bony Thorax
10-526-191
Edited by M. Rhodes
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc.





Bony Thorax
Formed by
 Sternum
 12 pairs of ribs
 12 thoracic vertebrae
Conical in shape
 Narrow at top
Posterior longer than anterior
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 2



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Protects heart and lungs
Supports wall of pleural cavity and diaphragm
Made to vary the volume of thoracic cavity during respiration
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 3

Posterior aspect of typical rib
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 4


12 pairs, numbered superiorly to inferiorly

Number corresponds to thoracic vertebra to which it attaches

Ribs are long, narrow, curved bones
 Anterior ends lie lower than posterior
(vertebral) ends
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 5


Vary in length and breadth
 First is shortest and broadest
 Increases in length from 1 to 7, then decreases to twelfth

Classified by attachment
 True ribs are 1 to 7 because they attach directly to sternum
 False ribs are 8 to 12 because they do not attach directly to the sternum
 Floating ribs are 11 and 12 because they only attach to the vertebrae
Slide 6 Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc.




Typical rib consists of
 Head
 Neck
 Tubercle
 Body
Heads articulate with vertebral bodies
 Form costovertebral joints
Tubercles articulate with T-spine transverse processes
 Form costotransverse joints
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 7

Enlarged image of rib and T-spine articulations
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 8





Centered on midline of anterior thorax
Narrow, flat bone
About 6
′′
(15 cm) in length
Three parts
 Manubrium – most superior
 Body
 Xiphoid process – most inferior
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 9



Supports clavicles at manubrial angles
 Forms sternoclavicular
(SC) joints
Provides attachment for costal cartilages of first seven pairs of ribs at lateral borders
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 10




Manubrium has jugular notch at superior border
 Palpable landmark
 Lies at T2-T3 interspace
Body is longest portion (about 4
′′
[10.2 cm])
 Joined to manubrium at sternal angle
 Sternal angle is palpable and lies at T4-T5 interspace
Xiphoid process is distal, smallest portion
 Often deviates from midline
 Useful landmark
 Lies over T10
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 11

Name
Sternoclavicular Joint
SC
Type
Synovial Joints - Gliding Joints
Movement
Fibrocartilage in joint space,
Articular capsules, freely moveable
Freely moveable Costovertebral
1 st – 12 ribs
Costotransverse
1 st – 10 th ribs
Synovial – Gliding
Costochondral
1 st – 10 th rib
Cartilaginous, Synchondroses
Sternocostal 1 st rib Cartilaginous – Synchondroses
2 nd – 7 th ribs Synovial – Gliding
Freely moveable
Immovable
Immovable
Freely moveable
Interchondral 6 th – 9 th ribs - Synovial – Gliding
9 th & 10 th ribs Fibrous – syndesmoses
Freely moveable
Slightly movable
Manubriosternal
Xiphisternal
Cartilaginous – symphysis
Cartilaginous – Synchondroses
Slightly moveable
Immovable
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 12

Bony Thorax
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 13


Patient preparation

General patient position

IR size

SID

ID markers

Radiation protection

Patient instructions
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 14


Patient preparation for bony thorax procedures requires removal of artifacts from the anatomy of interest
 Necklaces
 Clothing artifacts

Secure all patient possessions in designated manner and location

Check for pregnancy

Accommodate any trauma
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 15


Ambulatory patients
 Upright or recumbent

Nonambulatory patients
 Alter positioning to maximize patient comfort

SID

Textbook gives guidelines

Use smallest IR that will demonstrate anatomy

Collimate field size to anatomy of interest
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 16


SID is standardized as a part of procedural protocol
 30
′′
(76.2 cm) is recommended SID for PA oblique
 sternum
72
′′
(183 cm) SID is recommended for lateral sternum to reduce magnification and distortion caused by increased OID
 When SID is not specified under a projection,
Merrill’s Atlas recommends 48
′′
(122 cm)
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 17



Right or left side markers must be included on each image
Other required ID markers must be in the blocker or elsewhere on the final image



Shield patients of reproductive age and pediatrics
Other radiation protection measures
 Close collimation
 Optimum technique factors
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 18


Explain and demonstrate positions, when possible

Respiration instructions are essential for imaging the bony thorax
 Give clear explanations to reduce the need to repeat studies
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 19

Essential Projections of the
Bony Thorax
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 20


PA oblique
 RAO position

Lateral
 Upright
 Recumbent
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 21



Patient position
 15- to 20-degree recumbent RAO
Part position
 Ensure shoulders and hips rotated equal amount


Long axis aligned to midline
Top of IR 1.5
′′
(3.8 cm) above jugular notch
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 22

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

CR


Perpendicular to IR
Enters elevated side of posterior thorax 1
′′
(2.5 cm) lateral to MSP at level of T7
Can use breathing technique to blur lungs
 Instruct patient to take slow, shallow breaths during exposure
If short exposure time used, suspend breathing at end of expiration
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 23




Entire sternum from jugular notch to tip of xiphoid process
Sternum well visible through thorax
 Pulmonary markings blurred if breathing technique used
Minimally rotated sternum and thorax shown by
 Sternum free of superimposition by vertebral column
 Vertebrae minimally obliqued to prevent excessive rotation of sternum
 Lateral portion of manubrium and SC joint not overlapped by vertebrae
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 24

Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 25

Note: Draw large breast of females laterally and secure so the soft tissue shadows do not obscure sternum.

Patient position
 Upright, seated or standing
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 26





Part position
 Rotate shoulders posteriorly and lock hands behind back
 Center sternum to midline
 MSP vertical
 Top of IR placed so that upper border is 1.5
′′
(3.8 cm) above jugular notch
CR
 Perpendicular to IR
 Enters lateral border of sternum at midsternum
Use close collimation to improve image quality
Suspend respirations after deep inspiration
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 27


Patient position
 Lateral recumbent

Patient position
 True lateral without rotation
 Flex hips and knee for comfort
 Extend arms over head
 Adjust height of IR to place top border 1.5
′′
(3.8 cm) above jugular notch
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 28


CR
 Perpendicular to gridded IR
 Enters patient at lateral border of midsternum

Close collimation will improve image quality

Exposure made after patient suspends respiration at end of deep inspiration
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 29

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
Entire sternum
Manubrium free of superimposition by soft tissues of shoulders
Sternum free of superimposition by ribs
Lower portion of sternum not obscured by breast tissue in female patients
 Second radiograph with increased penetration may be needed
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 30


PA ( Upright or Prone)

PA oblique
 Body rotation method

PA oblique
 CR angulation method
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 31


Patient position
 Prone
 Upright facing vertical Bucky
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 32


Part position
 MSP aligned to midline of IR
 IR centered to spinous process of T3
 Shoulders in same transverse plane
 For bilateral examination, rest head on chin and adjust MSP of head to vertical
 For unilateral projection, turn head toward affected side and rest cheek on table

CR
 Perpendicular to center of IR
 Enters patient at MSP and T3

Suspend at end of expiration
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 33


Both SC joints and medial ends of clavicles

SC joints seen through ribs and vertebrae

No rotation on bilateral

Slight rotation seen on unilateral
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 34

Body Rotation Method


Patient position
 Recumbent or upright
Part position
 10- to 15-degree RAO or LAO position
 Affected side placed closer to IR
 SC joint in center
 Shoulders in same transverse plane
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 35

Body Rotation Method

CR


Perpendicular to SC joint closer to IR
Enters at level of T2-T3 (3
′′
, or 7.6 cm, distal to
C7) and 1
′′
to 2
′′
(2.5 to 5 cm) lateral, or toward the joint of interest, from MSP

Respirations suspended at end of expiration
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 36

CR Angulation Method
Note: This method images SC closer to IR with less distortion than body rotation method.

Patient position
 Prone (may be performed upright)
 Place grid IR directly under upper chest
 Center grid IR to SC joints
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 37

CR Angulation Method




Part position



Extends arms along side body with palms facing up
Shoulders in same transverse plane
Rest head on chin or rotate chin toward joint of interest
CR


 From side opposite joint of interest, angle
15 degrees toward MSP to midpoint of IR


Enters at level of T2-T3
(3
′′
, or 7.6 cm distal to C7) and 1
′′
to 2
′′
(2.5 to 5 cm) lateral to MSP
Respirations suspended at end of expiration
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 38





SC joint of interest in center of image
 Manubrium and medial end of clavicle included
Open SC joint space
SC joint of interest adjacent to vertebral column with minimal obliquity
SC joint clearly visible through superimposed rib and lungs
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 39

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



PA Chest
AP – Uppers & Lowers
 Posterior ribs
AP oblique – Uppers & Lowers
 Axillary portion
PA
 Upper, anterior ribs
PA oblique
 Axillary portion side away from IR
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 40


Patient position
 Upright or recumbent facing xray tube
 Upright recommended for upper ribs when patient’s condition permits to allow diaphragm to drop lower
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 41


Part position for upper ribs


MSP centered to midline of grid
Top of lengthwise IR 1.5
′′
(3.8 cm) above upper border of shoulders
 Rest hands, palms out, on hips
• Or extend arms, flex elbows, and rest hands under head
 Shoulders in same transverse plane and rotate forward to move out of ribs
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 42


Part position for lower ribs
 MSP centered to grid
 Crosswise IR with lower border level with iliac crests
 Remaining positioning same as for upper ribs
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 43


CR
 Perpendicular to center to IR

Respiration suspended at full inspiration for upper ribs
 Depresses diaphragm

Respiration suspended at end of full expiration for lower ribs
 Elevates diaphragm
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 44


For ribs above diaphragm, entire first to tenth posterior ribs on both sides

For ribs below diaphragm, entire eighth to twelfth posterior ribs on both sides

Ribs visible through lungs or abdomen

In unilateral examination, opposite ribs not entirely included
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 45

Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 46

Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 47


Patient position
 Upright or recumbent
 Upright recommended for ribs above diaphragm
 Recumbent patients require radiolucent support
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 48


Part position
 45-degree RPO or LPO
 Affected side closer to IR
 Center affected side on a longitudinal plane halfway between MSP and lateral surface of body
 Abduct and elevate arm of affected side
• Rest on head
 Abduct opposite limb and rest hand on hip
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 49


For upper ribs, place top of lengthwise IR
1.5
′′
(3.8 cm) above shoulders

For lower ribs, place lower edge of IR at level of iliac crests
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 50


CR
 Perpendicular to center of IR

Respirations suspended at end of deep inspiration for upper ribs

Respirations suspended at end of full expiration for lower ribs
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 51






About twice as much distance between vertebral column and lateral border of ribs seen on affected side
Axillary portion of ribs free of superimposition
For ribs above diaphragm, first to tenth ribs visible above diaphragm
For ribs below diaphragm, eighth to twelfth ribs visible below diaphragm
Ribs visible through lungs or abdomen
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 52

Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 53


Patient position
 Upright (seated or standing) or recumbent
 Upright allows diaphragm to descend to lowest position and demonstrates air-fluid levels in chest
• Recommended when patient’s condition permits
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 54




Part position


MSP centered to grid
Top of lengthwise IR 1.5
′′
(3.8 cm) above upper border of shoulders
 Rest hands, palms out, on hips
 Shoulders in same transverse plane
 If patient is prone, rest head on chin and adjust
MSP to vertical
CR
 Perpendicular to center of IR
Respiration suspended at end of full inspiration
 Depresses diaphragm
Slide 55 Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc.


Patient position
 Upright or recumbent
 Upright recommended for ribs above diaphragm when patient condition allows
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 56




Part position
 45-degree RAO or LAO
 Affected side away from IR
 Center affected side on a longitudinal plane halfway between MSP and lateral surface of body
 Abduct and elevate arm of affected side
• Rest on head
 Abduct opposite limb and rest hand on hip
For upper ribs, place top of lengthwise IR
1.5
′′
(3.8 cm) above shoulders
For lower ribs, place lower edge of IR at level of iliac crests
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 57


CR
 Perpendicular to center of IR

Respirations suspended at end of deep inspiration for upper ribs

Respirations suspended at end of full expiration for lower ribs
Mosby items and derived items © 2007, 2003, 1999 by Mosby, Inc., an affiliate of Elsevier Inc. Slide 58