APPENDICULAR
SKELETON
CHAPTER 8
THE PECTORAL GIRDLE
SECTION IV
Pectoral or Shoulder Girdle
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Consists of two bones, the anteriorly
positioned clavicle and the posteriorly
positioned scapula
Pectoral girdle is a loosely attached, held
in place largely by musculature attached
to the thorax and the vertebral column
Only direct ligament attachment exists at
the sternoclavicular joint
Frees girdle to move over the thorax as
the need arises
Pectoral Girdle
Flexible and Mobile
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Pectoral girdle is very light to allow the
upper limb flexibility and mobility not
allowed anywhere else in body
This is possible because only the sternal
end of clavicle is attached to axial skeleton
thus allowing the scapula to move across
thorax and the arm with it
The socket of the shoulder joint is shallow
and poorly reinforced
Although this arrangement does not
restrict movement it is less stable
Clavicles
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Clavicles are double curved bones extending along the
superior thorax
Attached on the sternal end to sternum and the
acromial
Attachment site or muscles of the thorax and shoulder
Position scapula away from thorax
Right Scapula
Anterior Aspect

Bone markings
are related to
– Joint structures
– Muscle
attachments
– Nerve and blood
vessels
Right Scapula
Posterior Aspect

Bone markings
are related to
– Joint structures
– Muscle
attachments
– Nerve and blood
vessels
Right Scapula
Lateral Aspect

Schematic
representation of
its orientation
THE UPPER LIMB
SECTION V
The Upper Limb
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Arm
– Humerus
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Forearm
– Ulna
– Radius
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Hand
Wrist (8 carpal bones)
Palm (5 metacarpal bones)
Fingers (14 phalanges)
The Humerus
Radius
and ulna
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Ulna is
involved in
elbow flexion
Radius is
involved with
supination
and
pronation
Carpals,
Metacarpals,
& Phalanges
THE PELVIC GIRDLE
SECTION VI
The Pelvic (Hip) Girdle
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Attaches the lower limbs to axial skeleton
Transfers the weight of the torso, head,
and upper extremities to lower limbs
Supports the visceral organs of the pelvis
Secured by strong ligaments and deep
sockets the joint is reinforced for stability
Less range of motion in all planes of
movement
Female pelvic structure to facilitate
childbearing
Pelvis
Pelvis
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Pelvic girdle is formed by a pair of coxal
bones, each called an os coxae
Each os coxae unites anteriorly at the
pubic symphysis and with the sacrum
posteriorly
Each coxa is formed by the ilium, ischium
and pubic which were separate during
childhood but fused in adulthood
Collectively the os coxae, sacrum and
coccyx is called the pelvis
Os Coxa
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Ilium
– Superior
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Ishium
– Posterior
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Pubis
– Anterior
Os Coxa
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Ilium
– Superior
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Ishium
– Posterior
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Pubis
– Anterior
Pelvic Structure and Childbearing
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The female pelvis reflects modifications
for child bearing
It tends to be wider, shallower, lighter,
and rounder than the male
Pelvic modifications accommodate the
growing fetus as well as providing a birth
canal wide enough to allow the infants
head to exit at birth
Pelvic inlet and outlet are critical to
delivery
Male and Female Pelvic Structures
THE LOWER LIMB
SECTION VII
The Lower Limb
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Thigh
– Femur
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Leg
– Tibia
– Fibula
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Foot (7 Tarsal bones)
Instep (5 Metatarsal bones)
Toes (14 Phalanges)
Femur
Tibia
Fibula
Bones of
Right Foot
Right Foot - Medial View
Right Foot - Lateral View
Arches of the Foot
DEVELOPMENTAL ASPECT
OF THE SKELETON
SECTION VIII
Developmental Aspects of the
Skeleton
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Fontanels
Spinal Curvatures
Long Bone Ratio
Changes in Female Pelvis
Adult Skeletal Changes
The Fetal Skull