PHARMA ANATOMOY
MIDTERM
Dr. Kaan Yücel
3.11.2011
1
2
The term human anatomy comprises a consideration of the various
structures which make up the human organism.
In a restricted sense it deals with the parts which form the fully
developed individual and which can be rendered evident to the
naked eye by various methods of dissection.
3
The three main approaches to studying anatomy are regional,
systemic, and clinical (or applied), reflecting the body's organization
and the priorities and purposes for studying it.
In systematic anatomy, various structures may be separately
considered.
The organs and tissues may be studied in relation to one another in
topographical or regional anatomy.
4
Surface anatomy
 An essential part of the study of regional anatomy.
 Provides knowledge of what lies under the skin and what structures
are perceptible to touch (palpable) in the living body at rest and in
action.
5
Systematic Anatomy
The various systems of which the human body:
Osteology—the bony system or skeleton.
Syndesmology—the articulations or joints.
Myology—the muscles.
Angiology—the vascular system, comprising the heart, blood vessels,
lymphatic vessels, and lymph glands.
Neurology—the nervous system. The organs of sense may be included
in this system.
Splanchnology—the visceral system.
6
The anatomical position refers to the body position as if the person
were standing upright with the:
 Head, eyes, and toes directed anteriorly (forward)
 Arms adjacent to the sides with the palms facing anteriorly
 Lower limbs close together with the feet parallel.
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Anatomical descriptions are based on four imaginary planes
(median, sagittal, frontal-coronal, and transverse-axial) that intersect
the body in the anatomical position.
Sagittal= New Latin sagittālis < sagitta (“arrow”)
Coronal= L. corona "crown, garland»
Axial = "pertaining to an axis,«
8
 The median plane, the vertical plane passing longitudinally through
the body, divides the body into right and left halves.
 Sagittal planes are vertical planes passing through the body parallel
to the median plane.
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Frontal (coronal) planes are vertical planes passing through the
body at right angles to the median plane, dividing the body into
anterior (front) and posterior (back) parts.
10
Transverse planes are horizontal planes passing through the body at
right angles to the median and frontal planes, dividing the body into
superior (upper) and inferior (lower) parts.
Radiologists refer to transverse planes as transaxial, which is
commonly shortened to axial planes.
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Medial is used to indicate that a structure is nearer to the median plane
of the body. For example, the 5th digit of the hand (little finger) is
medial to the other digits.
Lateral stipulates that a structure is farther away from the median
plane. The 1st digit of the hand (thumb) is lateral to the other digits.
Dorsum usually refers to the superior aspect of any part that protrudes
anteriorly from the body, such as the dorsum of the tongue, nose, penis,
or foot
12
Anatomical terms are specific for comparisons made in the anatomical
position, or with reference to the anatomical planes:
• Superior refers to a structure that is nearer the vertex, the topmost
point of the cranium (Mediev. L., skull).
• Inferior refers to a structure that is situated nearer the sole of the
foot.
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• Posterior (dorsal) denotes the back surface of the body or nearer to
the back.
• Anterior (ventral) denotes the front surface of the body.
To describe the relationship of two structures, one is said to be anterior
or posterior to the other insofar as it is closer to the anterior or
posterior body surface.
14
Proximal and distal are used when contrasting positions nearer to or
farther from the attachment of a limb or the central aspect of a linear
structure (origin in general), respectively. For example, the arm is
proximal to the forearm and the hand is distal to the forearm.
15
Terms of movement may also be considered in
pairs of oppositing movements:
Flexion and extension movements generally occur in
sagittal planes around a transverse axis.
16
Flexion indicates bending or decreasing the angle between the bones or
parts of the body. For most joints (e.g., elbow), flexion involves
movement in an anterior direction, but it is occasionally posterior, as in
the case of the knee joint.
Lateral flexion is a movement of the trunk in the coronal plane.
17
Extension indicates straightening or increasing the angle between the
bones or parts of the body. Extension usually occurs in a posterior
direction.
The knee joint, rotated 180° to other joints, is exceptional in that flexion
of the knee involves posterior movement and extension involves
anterior movement.
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19
OSTEOLOGY
BONES
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The skeletal system may be divided into
2 functional parts:
The axial skeleton
• head (cranium or skull)
• neck (hyoid bone and cervical vertebrae)
• trunk (ribs, sternum, vertebrae, and sacrum)
The appendicular skeleton
• Limbs
including those forming the shoulde & pelvic girdles
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 Bone has a protective function; the skull and vertebral column,
for example, protect the brain and spinal cord from injury; the
sternum and ribs protect the thoracic and upper abdominal
viscera.
 It serves as a lever, as seen in the long bones of the limbs, and as
an important storage area for calcium salts.
 It houses and protects within its cavities the delicate bloodforming bone marrow.
22
Classification of Bones
Bones are classified according to their shape.
1) Long bones
2) Short bones
3) Flat bones
4) Irregular bones
5) Sesamoid bones
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Classification of Bones
Long bones are tubular (e.g., the humerus in the arm).
24
Classification of Bones
Short bones are cuboidal and are found only in the tarsus (ankle) and
carpus (wrist).
25
Classification of Bones
Irregular bones have various shapes other than long, short, or flat (e.g.,
bones of the face).
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Classification of Bones
Sesamoid bones (e.g., the patella or knee cap) develop in certain
tendons and are found where tendons cross the ends of long bones in
the limbs; they protect the tendons from excessive wear and often
change the angle of the tendons as they pass to their attachments.
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 There are two types of bones according to histological features:
compact bone and spongy (trabecular) bone.
 They are distinguished by the relative amount of solid matter and by
the number and size of the spaces they contain.
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The skull is supported on the summit of the vertebral column, and is of
an oval shape, wider behind than in front.
It is composed of a series of flattened or irregular bones which, with one
exception (the mandible), are immovably jointed together. It is divisible
into two parts:
(1) cranium, which lodges and protects the brain, consists of 8 bones
(2) skeleton of the face, of 14
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Ossa Cranii
Occipital.
Two Parietals.
Frontal.
Cranium, 8 bones
Two Temporals.
Sphenoidal.
Ethmoidal.
Two Nasals.
Skull, 22 bones
Two Maxillæ.
Two Lacrimals.
Face, 14 bones
Two Zygomatics.
Two Palatines.
Two Inferior Nasal Conchæ.
Vomer.
Mandible.
30
31
Cranial Fossas
 The inferior and anterior parts of the frontal lobes of the brain
occupy the anterior cranial fossa, the shallowest of the three cranial
fossae.
 The fossa is formed by the frontal bone anteriorly, the ethmoid bone
in the middle, and the body and lesser wings of the sphenoid
posteriorly.
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The butterfly-shaped middle cranial fossa has a central part composed
of the sella turcica on the body of the sphenoid and large, depressed
lateral parts on each side.
33
 The posterior cranial fossa, the largest and deepest of the three
cranial fossae, lodges the cerebellum, pons, and medulla oblongata.
 The posterior cranial fossa is formed mostly by the occipital bone.
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The Facial Bones
1. Nasal Bones
2. Maxillæ (Upper Jaw)
3. Lacrimal Bone
4. Zygomatic Bone (Malar Bone)
5. Palatine Bone
6. Inferior Nasal Concha (Concha Nasalis Inferior; Inferior Turbinated
Bone)
7. Vomer
8. Mandible (Lower Jaw)
9. Hyoid Bone
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Ribs (L. costae) are curved, flat bones that form most of the thoracic
cage. There are 3 types of ribs:
 True (vertebrocostal) ribs (1st-7th ribs):
directly to the sternum.
 False (vertebrochondral) ribs
(8th, 9th, and usually 10th ribs):
indirect with the sternum
 Floating (vertebral, free) ribs
(11th, 12th, and sometimes 10th ribs):
No connection with the sternum
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Typical ribs (3rd-9th) have the following components:
 Head
 Neck
 Tubercle
 Body (shaft)
.
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Costal cartilages prolong the ribs anteriorly and contribute to the
elasticity of the thoracic wall, providing a flexible attachment for their
anterior ends.
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 Intercostal spaces separate the ribs and their costal cartilages from
one another.
 The spaces are named according to the rib forming the superior
border of the space—for example, the 4th intercostal space lies
between ribs 4 and 5.
 There are 11 intercostal spaces and 11 intercostal nerves. Intercostal
spaces are occupied by intercostal muscles and membranes, and two
sets (main and collateral) of intercostal blood vessels and nerves,
identified by the same number assigned to the space.
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G. sternon, chest
Has three parts:
1. Manubrium
2. Body
3. Xiphoid process
Jugular notch
@ sup. margin of the manubrium
Level of T2 vertebra
Clavicular notch
40
Vertebral column
 In an adult typically consists of 33 vertebrae arranged in five regions:
7 cervical, 12 thoracic, 5 lumbar, 5 sacral, and 4 coccygeal.
 The vertebrae gradually become larger as the vertebral column
descends to the sacrum and then become progressively smaller
toward the apex of the coccyx.
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 The change in size is related to the fact that successive vertebrae
bear increasing amounts of the body's weight as the column
descends.
 The vertebrae reach maximum size immediately superior to the
sacrum, which transfers the weight to the pelvic girdle at the
sacroiliac joints.
42
The vertebral column is flexible because it consists of many relatively
small bones, called vertebrae (singular = vertebra), that are separated
by resilient intervertebral (IV) discs.
43
 Vertebrae vary in size and other characteristics from one region of
the vertebral column to another, and to a lesser degree within each
region; however, their basic structure is the same.
 A typical vertebra consists of a vertebral body, a vertebral arch, and
seven processes.
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Clavicle (Tr. Köprücük kemiği)
 The clavicle (collar bone) connects the upper limb to the trunk.
 The shaft of the clavicle has a double curve in a horizontal plane.
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Clavicle (Tr. Köprücük kemiği)
 Its medial half is convex anteriorly, and its sternal end is
enlarged and triangular where it articulates with the manubrium
of the sternum at the sternoclavicular (SC) joint.
 Its lateral half is concave anteriorly, and its acromial end is flat
where it articulates with the acromion of the scapula at the
acromioclavicular (AC) joint.
 These curvatures increase the resilience of the clavicle and give
it the appearance of an elongated capital S.
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Some prominent features of the superior and inferior surfaces of the
clavicle:
Sternal end
Acromial end
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The clavicle:
 increases the range of motion of the limb.
 affords protection to the neurovascular bundle supplying the
upper limb.
 transmits shocks (traumatic impacts) from the upper limb to the
axial skeleton.
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Scapula (Tr. Kürek kemiği)
 The scapula (shoulder blade) is a triangular flat bone that lies on the
posterolateral aspect of the thorax.
 The convex posterior surface of the scapula is unevenly divided by a
thick projecting ridge of bone, the spine of the scapula, into a small
supraspinous fossa and a much larger infraspinous fossa.
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Scapula (Tr. Kürek kemiği)
 The concave costal surface of most of the scapula forms a large
subscapular fossa.
 The broad bony surfaces of the three fossae provide attachments for
fleshy muscles.
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Scapula (Tr. Kürek kemiği)
 The spine continues laterally as the flat expanded acromion which
forms the subcutaneous point of the shoulder and articulates with
the acromial end of the clavicle.
 Superolaterally, the lateral surface of the scapula has a glenoid cavity
which receives and articulates with the head of the humerus at the
glenohumeral joint.
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Humerus
 The humerus (arm bone), the largest bone in the upper limb,
articulates with the scapula at the glenohumeral joint and the radius
and ulna at the elbow joint.
 The proximal end of the humerus has a head, surgical and anatomical
necks, and greater and lesser tubercles.
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Humerus
 The spherical head of the humerus articulates with the glenoid
cavity of the scapula.
 The surgical neck of the humerus, a common site of fracture, is the
narrow part distal to the head and tubercles.
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Humerus
The distal end of the humerus—including the trochlea; the capitulum;
and the olecranon, coronoid, and radial fossae—makes up the
condyle of the humerus.
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 The ulna is the stabilizing bone of the forearm and is the medial and
longer of the two forearm bones.
 Its more massive proximal end is specialized for articulation with the
humerus proximally and the head of the radius laterally.
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For articulation with the humerus, the ulna has
two prominent projections:
1. Olecranon
projects proximally from its posterior aspect
(forming the point of the elbow)
and serves as a short lever for extension
of the elbow
2. Coronoid process
projects anteriorly.
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 The radius is the lateral and shorter of the two forearm bones. Its
proximal end includes a short head, neck, and medially directed
tuberosity.
 Proximally, the smooth superior aspect of the discoid head of the
radius is concave for articulation with the capitulum of the humerus
during flexion and extension of the elbow joint.
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Bones of the hand
 The wrist, or carpus, is composed of eight carpal bones (carpals)
arranged in proximal and distal rows of four.
 The proximal surfaces of the distal row of carpals articulate with the
proximal row of carpals, and their distal surfaces articulate with the
metacarpals.
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 The metacarpus forms the skeleton of the palm of the hand
between the carpus and the phalanges.
 It is composed of five metacarpal bones (metacarpals).
 The proximal bases of the metacarpals articulate with the carpal
bones, and the distal heads of the metacarpals articulate with the
proximal phalanges and form the knuckles.
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The skeleton of the lower limb (inferior appendicular skeleton) may be
divided into two functional components: the pelvic girdle and the bones
of the free lower limb.
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 The pelvic girdle is a ring of bones that connects the vertebral column
to the two femurs.
 The primary functions of the pelvic girdle are bearing and transfer of
weight
 secondary functions include protection and support of
abdominopelvic viscera and housing and attachment for structures of
the genital and urinary systems.
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In the mature individual, the pelvic girdle is formed by three bones:
Right and left hip bones (coxal bones; pelvic bones): large, irregularly
shaped bones, each of which develops from the fusion of three bones,
the ilium, ischium, and pubis.
Sacrum: formed by the fusion of five, originally separate, sacral
vertebrae.
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Coccyx (tail bone)
 Small triangular bone usually formed by fusion of the 4 rudimentary
coccygeal vertebrae. Remnant of the skeleton of the embryonic taillike caudal eminence
 Does not participate with the other vertebrae in support of the body
weight when standing; however, when sitting it may flex anteriorly
somewhat, indicating that it is receiving some weight.
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Femur
 Longest and heaviest bone in the body
 Transmits body weight from the hip bone to the tibia when a person
is standing.
 Consists of a shaft (body) and two ends, superior or proximal and
inferior or distal.
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Bones of the Leg
 The tibia and fibula are the bones of the leg.
 The tibia articulates with the condyles of the femur superiorly and
the talus inferiorly and in so doing transmits the body's weight.
 The fibula mainly functions as an attachment for muscles, but it is
also important for the stability of the ankle joint.
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Tibia
 Located on the anteromedial side of the leg, nearly parallel to the
fibula, the tibia (shin bone) is the second largest bone in the body.
 It flares outward at both ends to provide an increased area for
articulation and weight transfer.
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Fibula
 The distal end enlarges and is prolonged laterally and inferiorly as the
lateral malleolus.
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Bones of the foot
Tarsus (7 bones)
Metatarsus (5 bones)
Phalanges (14 phalanges)
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JOINTS
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 Joints (articulations) are unions or junctions between two or
more bones or rigid parts of the skeleton.
 Joints exhibit a variety of forms and functions. It is the fact that,
whether or not movement occurs between them, it is still
called a joint.
 Some joints have no movement, others allow only slight
movement, and some are freely movable
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Classification of Joints
Joints are classified according to the tissues that lie between the
bones:
1) Fibrous joints
2) Cartilaginous joints
3) Synovial joints
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Classification of Joints
Joints are classified according to the tissues that lie between the
bones:
1) Fibrous joints
2) Cartilaginous joints
3) Synovial joints
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Fibrous joints
 The bones are united by fibrous tissue.
 The amount of movement occurring at a fibrous joint
depends in most cases on the length of the fibers uniting the
articulating bones.
 The sutures of the cranium are examples of fibrous joints.
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 A syndesmosis type of fibrous joint unites the bones with a
sheet of fibrous tissue, either a ligament or a fibrous
membrane.
 Consequently, this type of joint is partially movable.
 The interosseous membrane in the forearm is a sheet of
fibrous tissue that joins the radius and ulna in a
syndesmosis.
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 A dentoalveolar syndesmosis (gomphosis or socket) is a
fibrous joint in which a peglike process fits into a socket
articulation between the root of the tooth and the alveolar
process of the jaw.
 Mobility of this joint (a loose tooth) indicates a pathological
state affecting the supporting tissues of the tooth.
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Cartilaginous joints
The bones are united by hyaline cartilage or fibrocartilage. In primary
cartilaginous joints, or synchondroses, the bones are united by hyaline
cartilage, which permits slight bending during early life.
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Secondary cartilaginous joints, or symphyses, are strong, slightly
movable joints united by fibrocartilage.
The fibrocartilaginous intervertebral discs between the vertebrae
consist of binding connective tissue that joins the vertebrae together.
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Synovial joints
 The bones are united by a joint (articular) capsule (composed of an
outer fibrous layer lined by a serous synovial membrane) spanning
and enclosing an articular cavity.
 Synovial joints are the most common type of joints and provide free
movement between the bones they join.
 They are joints of locomotion, typical of nearly all limb joints.
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This type of joints has three common features:
Joint cavity: The joint cavity of a synovial joint, like the knee, is a
potential space that contains a small amount of lubricating synovial
fluid, secreted by the synovial membrane.
Articular cartilage: The articular surfaces are covered by hyaline
cartilage
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Articular capsule: This structure surrounds the joint and formed of
two layers. Inside the capsule, articular cartilage covers the articulating
surfaces of the bones; all other internal surfaces are covered by synovial
membrane.
1. Fibrous capsule
2. Synovial membrane
Some synovial joints have other distinguishing features, such as a
fibrocartilaginous articular disc or meniscus, which are present when
the articulating surfaces of the bones are incongruous.
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Ligaments
 A ligament is a cord or band of connective tissue uniting two
structures.
 Articular capsules are usually strengthened by articular ligaments.
 These are from dense connective tissue and they connect the
articulating bones to each other.
 Articular ligaments limit the undesired
and/or excessive movements of
the joints.
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Articular disc: Help to hold the bones together.
Labrum: A fibrocartilaginous ring which deepens the articular surface
for one of the bones.
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Bursa
 Bursae are flattened sacs that contain synovial fluid to
reduce friction.
 Its walls are separated by a film of viscous fluid.
 Bursae are found wherever tendons rub against bones,
ligaments, or other tendons.
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Stability of Joints
depends on four main factors:
1) Negative pressure within the joint cavity
2) Shape, size, and arrangement of the articular surfaces
3) Ligaments
4) Tone of the muscles around the joint
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JOINTS OF THE VERTEBRAL COLUMN
The vertebral column in an adult typically consists of 33 vertebrae
arranged in five regions: 7 cervical, 12 thoracic, 5 lumbar, 5 sacral, and 4
coccygeal.
The joints of the vertebral column include the:
 Joints of the vertebral bodies
 Joints of the vertebral arches
 Craniovertebral (atlanto-axial and atlanto-occipital) joints
 Costovertebral joints
 Sacroiliac joints
85
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The joints of the vertebral bodies are designed for weight-bearing and
strength.
 The articulating surfaces of adjacent vertebrae are connected by
intervertebral (IV) discs and ligaments. The IV discs provide strong
attachments between the vertebral bodies.
87
The glenohumeral (shoulder) joint is a synovial joint that permits a
wide range of movement; however, its mobility makes the joint
relatively unstable.
The large, round humeral head articulates with the relatively shallow
glenoid cavity of the scapula, which is deepened slightly but effectively
by the ring-like, fibrocartilaginous glenoid labrum (L., lip).
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 The glenohumeral joint has more freedom of movement than
any other joint in the body.
 This freedom results from the laxity of its joint capsule and the
large size of the humeral head compared with the small size of
the glenoid cavity.
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The elbow joint, a synovial joint, is located inferior to the epicondyles of
the humerus.
 There are humeroulnar and humeroradial articulations.
 The collateral ligaments of the elbow joint are strong triangular
bands that are medial and lateral thickenings of the fibrous layer of
the joint capsule.
 The radial collateral ligament
 The ulnar collateral ligament
 Flexion and extension occur at the elbow joint.
 Intratendinous olecranon bursa
 Subtendinous olecranon bursa
 Subcutaneous olecranon bursa
90
91
 The wrist (radiocarpal) joint is a synovial joint. The ulna does not
participate in the wrist joint.
The distal end of the radius and the articular disc of the distal radio-ulnar
joint articulate with the proximal row of carpal bones, except for the
pisiform.
 The intercarpal (IC) joints interconnect the carpal bones.
 The carpometacarpal (CMC), intermetacarpal (IM) joints,
metacarpophalangeal joints, and interphalangeal joints are other
joints in the hand.
92
The hip joint forms the connection between the lower limb
and the pelvic girdle. It is a strong and stable synovial joint.
 The head of the femur is the ball, and the acetabulum is the socket.
 The hip joint is designed for stability over a wide range of
movement.
 Next to the glenohumeral (shoulder) joint, it is the most movable of
all joints.
 During standing, the entire weight of the upper body is transmitted
through the hip bones to the heads and necks of the femurs.
93
 The round head of the femur articulates with the cup-like acetabulum
of the hip bone.
 The lip-shaped acetabular labrum (L. labrum, lip) is a
fibrocartilaginous rim attached to the margin of the acetabulum,
increasing the acetabular articular area by nearly 10%.
 The hip joints are enclosed within strong joint capsules, formed of a
loose external fibrous layer (fibrous capsule) and an internal synovial
membrane.
94
The knee joint is our largest and most superficial joint. It is a synovial
joint, allowing flexion and extension; however, the these movements
are combined with gliding and rolling and with rotation.
Although the knee joint is well constructed, its function is commonly
impaired when it is hyperextended.
The articular surfaces of the knee joint are characterized by their large
size and their complicated and incongruent shapes.
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The ankle joint (talocrural articulation) is located between the distal
ends of the tibia and the fibula and the superior part of the talus.
The ankle joint is reinforced laterally by the lateral ligament of the ankle.
The many joints of the foot involve the tarsals, metatarsals, and
phalanges.
96
 All skeletal muscles are composed of one specific type of muscle
tissue.
 These muscles move the skeleton, therefore, move the body parts.
97
There are three muscle types:
Skeletal striated muscle is voluntary somatic muscle that makes up the
gross skeletal muscles that compose the muscular system, moving or
stabilizing bones and other structures (e.g., the eyeballs).
Innervated by the somatic nervous system.
98
Cardiac striated muscle is involuntary visceral muscle that forms most
of the walls of the heart and adjacent parts of the great vessels, such
as the aorta, and pumps blood.
99
Smooth muscle (unstriated muscle) is involuntary visceral muscle that
forms part of the walls of most vessels and hollow organs (viscera),
moving substances through them by coordinated sequential
contractions (pulsations or peristaltic contractions).
Innervated by the autonomic nervous system.
100
Skeletal Muscles
Form, Features, and the Naming of muscles
 All skeletal muscles, commonly referred to simply as “muscles,” have
fleshy, reddish, contractile portions (one or more heads or bellies)
composed of skeletal striated muscle.
 Some muscles are fleshy throughout, but most also have white noncontractile portions (tendons), composed mainly of organized
collagen bundles, that provide a means of attachment.
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 Most skeletal muscles are attached directly or indirectly to bones,
cartilages, ligaments, or fascias or to some combination of these
structures.
 Some muscles are attached to organs (the eyeball, for example), skin
(such as facial muscles), and mucous membranes (intrinsic tongue
muscles).
 Muscles are organs of locomotion (movement), but they also provide
static support, give form to the body, and provide heat.
102
The architecture and shape of muscles vary.
The tendons of some muscles form flat sheets, or aponeuroses, that
anchor the muscle to the skeleton and/or to deep fascia (such as the
latissimus dorsi muscle of the back), or to the aponeurosis of another
muscle (such as the oblique muscles of the anterolateral abdominal
wall).
103
Many terms provide information about a structure's
 Shape
 Size
 Location
 Function
 Resemblance of one structure to another
104
105
 Attachments of muscles are commonly described as the origin and
insertion.
 The origin is usually the proximal end of the muscle, which remains
fixed during muscular contraction.
 The insertion is usually the distal end of the muscle, which is
movable.
 This is not always the case. Some muscles can act in both directions
under different circumstances.
106
Whereas the structural unit of a muscle is a skeletal striated muscle
fiber, the functional unit of a muscle is a motor unit, consisting of a
motor neuron and the muscle fibers it controls.
107
Functions of muscles
Muscles serve specific functions in moving and positioning the body.
A prime mover (agonist) is the main muscle responsible for producing a
specific movement of the body.
It contracts concentrically to produce the desired movement, doing
most of the work (expending most of the energy) required.
108
A fixator steadies the proximal parts of a limb through isometric
contraction while movements are occurring in distal parts.
A synergist complements the action of a prime mover.
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An antagonist is a muscle that opposes the action of another muscle.
The same muscle may act as a prime mover, antagonist, synergist, or
fixator under different conditions.
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Cutaneous (sensory) innervation of the face and anterosuperior
part of the scalp is provided primarily by the trigeminal nerve (CN
V), whereas motor innervation to the facial muscles is provided by
the facial nerve (CN VII).
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Muscles of the Neck
 The sternocleidomastoid (SCM) muscle is a broad, strap-like muscle
that has two heads:
 The rounded tendon of the sternal head attaches to the manubrium,
and the thick fleshy clavicular head attaches to the superior surface of
the clavicle.
 Bilateral contractions of the SCMs will cause extension of the
elevating the chin.
 Acting unilaterally, the SCM laterally flexes the neck (bends the neck
sideways) and rotates the head so the ear approaches the shoulder of
the ipsilateral (same) side.
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Trapezius is a large, flat triangular muscle that covers the posterolateral
aspect of the neck and thorax.
The trapezius provides a direct attachment of the pectoral girdle to the
trunk. This large, triangular muscle covers the posterior aspect of the
neck and the superior half of the trunk.
It was given its name because the muscles of the two sides form a
trapezium (G. irregular four-sided figure). The trapezius assists in
suspending the upper limb.
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 The posterior axioappendicular muscles (superficial and
intermediate groups of extrinsic back muscles) attach the
superior appendicular skeleton (of the upper limb) to the axial
skeleton (in the trunk).
The posterior shoulder muscles are divided into three groups:
 Superficial posterior axioappendicular (extrinsic shoulder)
muscles: trapezius and latissimus dorsi.
 Deep posterior axioappendicular (extrinsic shoulder) muscles:
levator scapulae and rhomboids.
 Scapulohumeral (intrinsic shoulder) muscles: deltoid, teres
major, and the four rotator cuff muscles.
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The name latissimus dorsi (L. widest of back) was well chosen
because the muscle covers a wide area of the back.
This large, fan-shaped muscle passes from the trunk to the
humerus and acts directly on the glenohumeral joint and
indirectly on the pectoral girdle (scapulothoracic joint).
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 The six scapulohumeral muscles (deltoid, teres major, supraspinatus,
infraspinatus, subscapularis, and teres minor) are relatively short
muscles that pass from the scapula to the humerus and act on the
glenohumeral joint.
 THE ONES IN PURPLE ARE ROTATOR CUFF MUSCLES. PLEASE VISIT THE
LINK FOR THE DEFINITION!
 The deltoid is a thick, powerful, coarse-textured muscle covering the
shoulder and forming its rounded contour. As its name indicates, the
deltoid is shaped like the inverted Greek letter delta (Δ).
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Muscles of the Arm & the Hand
Of the four major arm muscles, three flexors (biceps brachii,
brachialis, and coracobrachialis) are in the anterior (flexor)
compartment, supplied by the musculocutaneous nerve, and
one extensor (triceps brachii) is in the posterior compartment,
supplied by the radial nerve. The ulnar nerve supplies the flexor
carpi ulnaris and flexor digitorum profundus (media half) and
hypothenar muscles.
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 The biceps brachii is the flexor of the arm.
 The brachialis is the main flexor of the forearm.
 The coracobrachialis helps flex and adduct the arm and stabilize the
glenohumeral joint.
 The triceps brachii is the main extensor of the forearm.
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The flexor muscles of the forearm are in the anterior (flexor-pronator)
compartment of the forearm and are separated from the extensor
muscles of the forearm by the radius and ulna and, in the distal two
thirds of the forearm, by the interosseous membrane that connects
them.
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The extensor muscles of the forearm are in the posterior (extensorsupinator) compartment of the forearm, and all are innervated by
branches of the radial nerve.
The intrinsic muscles of the hand are located in five compartments.
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Muscles of the Gluteal Region, Back, the Leg & the Foot
The large anterior compartment of the thigh contains the
anterior thigh muscles, the flexors of the hip and extensors of the knee.
The pectineus is a flat quadrangular muscle located in the anterior part
of the thigh.
The iliopsoas is the chief flexor of the thigh, the most powerful of the
hip flexors.
The sartorius, the “tailor's muscle” (L. sartus, patched or repaired), is
long and ribbon-like. It passes lateral to medial across the
superoanterior part of the thigh. The sartorius, the longest muscle in the
body.
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The quadriceps femoris (L., four-headed femoral muscle) forms the main bulk of the
anterior thigh muscles and collectively constitutes the largest and one of the most
powerful muscles in the body.
It covers almost all the anterior aspect and sides of the femur.
The quadriceps femoris (usually shortened to quadriceps) is the great extensor of
the leg.
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Gluteal and posterior thigh regions
The gluteus maximus is the most superficial gluteal muscle.
It is the largest, heaviest, and most coarsely fibered muscle
of the body. The main actions of the gluteus maximus are
extension and lateral rotation of the thigh.
The smaller gluteal muscles, gluteus medius and gluteus
minimus, are fan shaped, and their fibers converge in the
same manner.
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The gastrocnemius and soleus share a common tendon, the calcaneal
tendon, which attaches to the calcaneus.
The calcaneal tendon (L. tendo calcaneus, Achilles tendon) is the most
powerful (thickest and strongest) tendon in the body.
Collectively these two muscles make up the three-headed triceps surae
(L. sura, calf).
These muscles raise heel during walking; flex the leg at the knee joint.
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