Musculoskeletal Anatomy: Arm

Question 1

What are the muscles of the anterior compartment of the arm?

Answer 1

Biceps brachii, coracobrachialis, brachialis.

Question 2

What is the origin, insertion, and action of biceps brachii?

Answer 2

O: Supraglenoid tubercle of the scapula (long head) and Coracoid process (short head) | I: Radial tuberosity | A: Supination of the forearm, flexion of the elbow and accessory flexion at the glenohumeral joint.

Question 3

What is the origin, insertion, and action of coracobrachialis?

Answer 3

O: Coracoid process | I: the anterior shaft of the humerus | A: flexion of the arm at the glenohumeral joint.

Question 4

What is the origin, insertion, and action of brachialis?

Answer 4

O: anterior shaft of the humerus | I: Ulnar tuberosity | A: flexion of the elbow.

Question 5

What are the muscles of the posterior compartment of the arm?

Answer 5

Triceps brachii and anconeus

Question 6

What is the origin, insertion, and action of triceps brachii?

Answer 6

O: infraglenoid tubercle of the scapula (long head), the posterior shaft of the humerus above the radial groove (lateral), and posterior shaft of the humerus below the radial groove (medial head) | I: olecranon | A: extension of the forearm at the elbow.

Question 7

What is the origin, insertion, and action of the anconeus?

Answer 7

O: lateral epicondyle of the humerus | I: Olecranon | A: Extension of the forearm at the elbow.