Slide 5.32b Download

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The Skeletal System
The Appendicular Skeleton
 Limbs (appendages)
 Pectoral girdle
 Pelvic girdle
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Slide
The Appendicular Skeleton
Figure 5.6c
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Slide
The Pectoral (Shoulder) Girdle
 Composed of two bones
 Clavicle – collarbone
 Scapula – shoulder blade
 These bones allow the upper limb to
have exceptionally free movement
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Slide 5.33
Bones of the Shoulder Girdle
Figure 5.20a, b
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Scapulae (Shoulder Blade)
• Situated on the dorsal surface of rib
cage, between ribs 2 and 7
• Flat and triangular, with three borders
and three angles
• Seven large fossae, named according to
location
Acromion
Suprascapular notch
Superior border
Coracoid
process
Glenoid
cavity
Lateral border
Superior
angle
Subscapular
fossa
Medial border
(a) Right scapula, anterior aspect
Inferior angle
Figure 7.25a
Suprascapular notch
Coracoid process
Superior
angle
Supraspinous
fossa
Spine
Infraspinous
fossa
Acromion
Glenoid
cavity
at lateral
angle
Medial border
Lateral border
(b) Right scapula, posterior aspect
Figure 7.25b
Supraspinous fossa
Acromion
Coracoid
process
Supraspinous
fossa
Infraspinous
fossa
Posterior
Spine
Glenoid
cavity
Subscapular
fossa
Anterior
(c) Right scapula, lateral aspect
Inferior angle
Figure 7.25c
The Upper Limb
• 30 bones form the skeletal framework of
each upper limb
– Arm
• Humerus
– Forearm
• Radius and ulna
– Hand
• 8 carpal bones in the wrist
• 5 metacarpal bones in the palm
• 14 phalanges in the fingers
Humerus
 The arm is formed by
a single bone
 Humerus
• Largest, longest bone
of upper limb
• Articulates superiorly
with glenoid cavity of
scapula
• Articulates inferiorly
with radius and ulna
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Figure 5.21a, b
Slide
Radius and Ulna
• The forearm has
two bones
• Ulna
• Radius
Figure 5.21c
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Slide
Radius & Ulna
• Ulna
– Medial bone in forearm
– Forms the major portion of the
elbow joint with the humerus
• Radius
– Lateral bone in forearm
– Interosseous membrane connects
the radius and ulna along their
entire length
Figure 5.21c
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Slide
Head
Olecranon
process
Trochlear
notch
Neck
Radial
tuberosity
Proximal
radioulnar
joint
Interosseous
membrane
Ulna
Head of
radius
Neck of
radius
Radius
Ulnar notch
Radius
of the radius
Head of ulna
Styloid
Styloid
process of ulna
process
Distal radioulnar
Styloid process
of radius
joint
of radius
(a) Anterior view
(b) Posterior view
Figure 7.27a-b
Bones of the Upper Limb
 The hand
 Carpals – wrist
 Metacarpals –
palm
 Phalanges –
fingers
Figure 5.22
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Slide 5.36
Hand: Carpals
• Eight bones in two rows
– Proximal row
– Distal row
• The scaphoid is the most
broken bone in the wrist.
Figure 5.22
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Hand: Metacarpals and Phalanges
• Metacarpals
– Five metacarpal bones
(#1 to #5) form the palm
• Phalanges
– Each finger (digit), except
the thumb, has three
phalanges—distal, middle,
and proximal
– Fingers are numbered 1–5,
beginning with the thumb
(pollex)
Figure 5.22
– Thumb has no middle
phalanx
Bones of the Pelvic Girdle (Coxal)
 Hip bones
 Composed of three pair of fused bones
 Ilium
 Ischium
 Pubic bone
 The total weight of the upper body rests on the
pelvis
 Protects several organs
 Together with the sacrum and the coccyx, these
bones form the bony pelvis
Ilium
Posterior
superior
iIiac spine
Posterior inferior
iliac spine
Greater sciatic
notch
Ischial body
Ischium
Ischial
tuberosity
Iliac crest
Anterior
superior
iliac spine
Anterior inferior
iliac spine
Acetabulum
Pubic body
Pubis
Obturator foramen
(a) Lateral view, right hip bone
Figure 7.30a
The Pelvis
Figure 5.23a
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Slide
Bones of the Lower Limb
• Carries the weight of the body
• Subjected to exceptional forces
• Three segments of the lower limb
– Thigh: femur
– Leg: tibia and fibula
– Foot: 7 tarsal bones in the ankle, 5
metatarsal bones in the metatarsus, and
14 phalanges in the toes
Neck
Fovea
capitis
Greater
trochanter
Head
Lesser trochanter
Apex
Anterior
Facet for
medial
condyle
of femur
Facet for lateral
condyle of femur
Lateral
condyle
Lateral
epicondyle
Surface for
patellar
Posterior
ligament
(a) Patella (kneecap)
Medial condyle
Lateral epicondyle
Patellar surface
Medial
epicondyle
Anterior view
Posterior view
(b) Femur (thigh bone)
Figure 7.31
Femur
• Largest and
strongest bone in
the body
• Articulates
proximally with the
acetabulum of the
hip and distally
with the tibia and
patella
Bones of the Leg
• Tibia
– Medial leg bone
– Receives the weight of the
body from the femur and
transmits it to the foot
• Fibula
– Not weight bearing; no
articulation with femur
– Site of muscle attachment
– Connected to tibia by
interosseous membrane
Lateral condyle
Head
Proximal tibiofibular
joint
Medial condyle
Tibial tuberosity
Interosseous membrane
Fibula
Tibia
Distal tibiofibular
joint
Lateral malleolus
Medial malleolus
(a) Anterior view
Figure 7.32a
Bones of the Foot (Tarsals)
• Seven tarsal bones form the posterior
half of the foot
• Talus transfers most of the weight from
the tibia to the calcaneus
• Other tarsal bones: cuboid, navicular,
and the medial, intermediate, and lateral
cuneiforms
Intermediate
cuneiform
First metatarsal
Talus Facet for
medial
Navicular
malleolus
Sustentaculum tali
(talar shelf)
Calcaneus
Medial
cuneiform
(b) Medial view
PLAY
Calcaneal
tuberosity
Animation: Rotatable bones of the foot
Figure 7.33b
Foot: Metatarsals and Phalanges
• Metatarsals:
– Five metatarsal bones (#1 to #5)
– Enlarged head of metatarsal 1 forms
the “ball of the foot”
• Phalanges:
– The 14 bones of the toes
– Each digit (except the hallux) has
three phalanges
– Hallux has no middle phalanx
Distal
Middle
Proximal
1
Medial
cuneiform
Intermediate
cuneiform
Navicular
Talus
Trochlea
of talus
(a) Superior view
2
3
4
5
Phalanges
Metatarsals
Lateral
cuneiform
Cuboid
Tarsals
Calcaneus
Figure 7.33a
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