SHOULDER FUNCTION

Question 1

3 joints of the elbow

Answer 1

ulnohumeral joint
Radiohumeral joint
Proximal radioulnar joint

Question 2

Medial collateral ligament

Answer 2

provides resistance to valgus forces

Question 3

Lateral Collateral ligament

Answer 3

provides resistance to varus forces

Question 4

Elbow flexors

Answer 4

Biceps brachii
Brachialis
Brachioradialis

Question 5

Biceps brachii

Answer 5

O: Supraglenoid tubercle of scapula
SH- tip of the coracoid process
I: Radial tuberosity and fascia of forearm via bicipital aponeurosis
Action: supinates the forearm, flexes the elbow. Short head resists dislocation
Inn: Musculocutaneous nerve (C5,6,7)

Question 6

Brachialis

Answer 6

O: Distal 1/2 of anterior surface of humerus
I: coronoid process and tuberositiy of ulna
Action: Flex the elbow
Inn: Musculocutaneous nerve (C5,6,7) small branch from radial nerve

Question 7

Brachioradialis

Answer 7

O: Proximal 2/3 lateral supracondylar ridge of humerus
I: Lateral surface of distal end of radius
Action: flexes elbow joint, especially in semi-pronated position
Inn radial nerve (C5,6,7)

Question 8

Extensors of elbow

Answer 8

Triceps brachii
anconeus

Question 9

triceps brachii

Answer 9

O: Long head- infraglenoid tubercle of scapula
Lateral head- Posterior surface of humerus, superior to the radial groove
Medial head- Posterior surface of humerus, inferior to radial groove
I: Proximal end of olecranon of ulna and fascia of forearm
Action: extends elbow, long head resists dislocation of shoulder, especially during adduction
inn: radial nerve (C6,7,8)

Question 10

Anconeus

Answer 10

O: Lateral epicondyle of humerus
I: Lateral surface of olecranon and superior part of posterior surface of ulna
Action: Assists triceps in elbow extension, stabilize elbow joint and may abduct the ulna during pronation
Inn: Radial nerve (C7, C8, T1)