Arm

Question 1

Biceps Brachii

Answer 1

Origin:

• short head: coracoid process of scapula
• long head: supraglenoid tubercle of scapula

Insertion: tuberosity of radius and ulna and aponeurosis of biceps brachia

Action: flex elbow, supinate forearm, flex shoulder

Nerve: musculocutaneous nerve C5, 6

Question 2

Brachialis

Answer 2

Origin: distal half of anterior surface of humerus

Insertion: tuberosity and coracoid process of ulna

Action: flex elbow

Nerve: musculocutaneous nerve, small branch from radial nerve C5, 6

Question 3

Coracobrachialis

Answer 3

Origin: coracoid process of scapula

Insertion: medial surface of mid-humeral shaft

Action: flex shoulder, adduct shoulder

Nerve: musculocutaneous nerve C6, 7

Question 4

Triceps Brachii

Answer 4

Origin:

• long head: infraglenoid tubercle of scapula
• lateral head: posterior surface of proximal half of humerus
• medial head: posterior surface of distal half of humerus

Insertion: olecranon process of ulna

Action:

• all head: extend elbow
• long head: extend shoulder, adduct shoulder

Nerve: radial nerve C6, 7, 8, T1

Question 5

Anconeus

Answer 5

Origin: lateral epicondyle of humerus

Insertion: olecranon process

Action: extend elbow

Nerve: radial nerve C7, 8