CHI108 Week 3 - Upper and Lower Appendicular Skeleton class notes

W3 L3

Lecture 3 – Upper and lower appendicular
skeleton and skeletal muscle architecture
Learning objectives

1. Identify the key primary skeletal structures and features on the bones of the upper and lower
appendicular skeleton.
2. Examine the generalised gross structural organisation of the skeletal bones and conceptually
continue to develop your knowledge surrounding the synovial joints of both the upper and lower
appendicular skeleton.
3. Compare and contrast the different morphology of direct and indirect muscle attachments.
4. Describe the different forms of architectural arrangements observed within skeletal muscles.
5. Review the differences seen between various muscles in relation to their anatomical and
physiological cross-sectional area

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The appendicular skeleton

• 1 upper limb; n = 32 • 1 lower limb; n = 31
• Pectoral girdle • Pelvic girdle
○ Clavicle o Ilium
○ Scapula o Ischium
• Upper limb o Pubis
○ Humerus • Lower limb
○ Radius o Femur
○ Ulna o Patella
• 8 carpal bones o Tibia
○ Scaphoid o Fibula
○ Lunate • 7 tarsal bones
○ Triquetrum o Talus
Skeleton of the right upper limb
○ Pisiform o Calcaneus
Palpable bony prominences on the upper limb
o Navicular
○ Trapezium
o Cuboid
○ Trapezoid
o Lateral, intermediate, and medial cuneiform
○ Capitate
○ Hamate • 5 metatarsal
• 5 metacarpal • 14 phalanges
• 14 phalanges


The pectoral girdle

Clavicle

• A long bone that serves as a strut between the scapula and the sternum
• The only long bone in the body that lies on the horizontal plane
• Medially, it forms the sternoclavicular joint between clavicular notch of manubrium and sternal
end of clavicle
• The articular surface of the clavicle is much larger than that of the manubrium
• Laterally, it articulates with the acromion of the scapula at the acromioclavicular joint
• Medial 2/3 convex anteriorly; lateral 1/3 concave anteriorly
• Distinguishing structures include
○ Sternal end
○ Acromial end
○ Superior surface
○ Inferior surface
○ Conoid tubercle Position and shape of the right clavicle
○ Costal tuberosity (costoclavicular ligament)

Scapula

• A thin flat triangular bone that connects the humerus with the clavicle
• Located on the posterior surface of the thoracic cage
• The muscles of the rotator cuff attach to the scapula
• Distinguishing structures include
o Spine of the scapula
o Acromion process
o Coracoid process
The right scapula, ant. & post. view
o Superior border
o Medial border
o Lateral border
o Superior angle
o Inferior angle
o Subscapular fossa
o Supraspinous fossa
o Infraspinous fossa
o Glenoid cavity
o Supraglenoid tubercle
o Infraglenoid tubercle


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, o Supraspinous fossa
o Infraspinous fossa
o Glenoid cavity
o Supraglenoid tubercle
o Infraglenoid tubercle

Upper limb

The humerus

• The long bone of the brachium connecting the scapula to the two bones of the antebrachium, the
radius and ulna
• Proximal humerus The right humerus, ant. post. lat. & med. view
o Head of humerus
o Greater tubercle
o Intertubercular sulcus
▪ Intertubercular groove
▪ Bicipital groove
o Lesser tubercle
o Deltoid tuberosity
• Distal humerus
o Lateral epicondyle
o Medial epicondyle
• Anterior distal surface
o Radial fossa is proximal to capitulum
o Coronoid fossa is proximal to trochlea
• Posterior distal surface
o Olecranon fossa (midline)

Ulna and radius

• The ulna is a long bone on the medial side of the antebrachium when in anatomical position
• It connects the elbow to the hand while lying parallel to the radius
• It is larger and longer than the radius The radius and ulna of the right forearm
• Proximal ulna
o Olecranon process
o Trochlear notch
o Coronoid process
▪ Ulna tuberosity
o Radial notch of the ulna
• Diaphysis
o Interosseous border of the ulna
• Distal ulna
o Ulnar styloid process
o Head of ulna

• The radius is a lone bone located on the lateral side of the antebrachium when in the anatomical
position
• It connects the elbow to the hand while lying parallel to the ulna
• Proximal radius
o Radial head
o Radial tuberosity
• Diaphysis
o Interosseous border of the radius The radius and ulna of the right arm in (a)
• Distal radius supination and (b) pronation
o Radial styloid process
o Ulnar notch of the radius

Carpal bones

• The carpals are eight short bones that make up the wrist
• They connect the hand to the antebrachium
• From lateral to medial, the proximal row of the carpal bones are as follows
1. Scaphoid Some
2. Lunate Lovers ,
3. Triquetrum
Try
4. Pisiform
Positions
• From lateral to medial, the distal row of the carpal bones are as follows The bones of the right hand, plan. & dors. view
That
1. Trapezium
2. Trapezoid They
3. Capitate Can't
4. Hamate Handle

The hand

• The 14 phalanges are long bones, with the pollex (thumb) having two phalanges and the other
digits have three phalanges
• The 5 metacarpals are long bones, forming the intermediate part of the hand located between the
carpal bones of the wrist and the phalanges of the fingers
• There is an inconstant number of sesamoid bones in the hand
• Phalanges and metacarpals have three regions:
o Distally they are referred to as the head
o The diaphysis is known as the shaft
o Proximally they are referred to as the base

Pelvic girdle
Carpal bones of the right hand


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