Download The Appendicular Skeleton

The Appendicular Skeleton
• Includes:
– Limbs (appendages)
– Pectoral girdle (Shoulder joint)
– Pelvic girdle (hip joint)
© 2015 Pearson Education, Inc.
The Pectoral (Shoulder) Girdle
• Composed of two bones that attach the upper
limbs to the axial skeleton
1. Scapula
2. Clavicle
• Allows the upper limb a great deal of freedom
© 2015 Pearson Education, Inc.
Figure 5.23a Bones of the shoulder girdle.
Acromioclavicular joint
Clavicle
Scapula
(a) Articulated right shoulder (pectoral)
girdle showing the relationship to
bones of the thorax and sternum
Figure 5.23b Bones of the shoulder girdle.
Sternal
(medial)
end
Posterior
Acromial
(lateral) end
Superior view
Acromial end
Anterior
Anterior
Sternal end
Posterior
Inferior view
(b) Right clavicle, superior and
inferior views
Figure 5.23c Bones of the shoulder girdle.
Coracoid process
Suprascapular notch
Superior
angle
Spine
Acromion
Glenoid cavity
at lateral angle
Medial
border
Lateral border
(c) Right scapula, posterior aspect
Figure 5.23d Bones of the shoulder girdle.
Acromion
Suprascapular notch
Superior border
Superior
angle
Coracoid
process
Glenoid
cavity
Lateral
(axillary)
border
Medial
(vertebral)
border
Inferior angle
(d) Right scapula, anterior aspect
The Arm
• One bone: The Humerus
– At the proximal end, the head articulates with the
glenoid cavity of the scapula
• This is a ball and socket joint
– At the distal end, the trochlea and capitulum
articulate with the bones of the forearm
© 2015 Pearson Education, Inc.
Figure 5.24a Bones of the right arm and forearm.
Greater
tubercle
Lesser
tubercle
Head of
humerus
Anatomical
neck
Intertubercular
sulcus
Deltoid
tuberosity
(a)
Radial
fossa
Coronoid
fossa
Medial
epicondyle
Capitulum
Trochlea
Figure 5.24b Bones of the right arm and forearm.
Head of
humerus
Anatomical
neck
Surgical
neck
Radial
groove
Deltoid
tuberosity
Medial
epicondyle
(b) Trochlea
Olecranon
fossa
Lateral
epicondyle
The Forearm
• Two bones
1. Ulna—medial bone in anatomical position
• Proximal end articulation
– Coronoid process and olecranon articulate with the humerus
2. Radius—lateral bone in anatomical position
• Olecranon gives us the distinct elbow
© 2015 Pearson Education, Inc.
Figure 5.24c Bones of the right arm and forearm.
Trochlear
notch
Olecranon
Head
Neck
Radial
tuberosity
Coronoid
process
Proximal
radioulnar
joint
Radius
Ulna
Interosseous
membrane
(c)
Radial
styloid
process
Ulnar
styloid
process
Distal
radioulnar joint
Hands
• Carpals—wrist
– arranged in two rows of 4 bones in each hand
– Scaphoid, lunate, triquetrum, pisiform (Row 1)
– trapezium, trapezoid, capitate, hamate (Row 2)
• “some lovers try positions that they can’t handle”
• Metacarpals—palm (5 per hand)
• Phalanges—fingers and thumb
– In each finger, there are 3 bones
– In the thumb, there are only 2 bones
• Thumb is called the pollex
© 2015 Pearson Education, Inc.
Figure 5.25 Bones of the right hand, anterior view.
Distal
Phalanges
(fingers)
Middle
Proximal
Metacarpals
(palm)
Carpals
(wrist)
4
3
2
5
1
Hamate
Trapezium
Pisiform
Triquetrum
Trapezoid
Scaphoid
Capitate
Lunate
Ulna
Radius