Anterior compartment of the arm

Question 1

What are the 3 muscles of the anterior compartment of the arm and

Answer 1

Biceps Brachii, Brachialis, Coracobrachialis

Question 2

What nerve innervates all the muscles of the the anterior compartment of the arm

Answer 2

musculocutaneous nerves

Question 3

What is the origin, insertion, action and innervation of Biceps Brachii,

Answer 3

Origin: Scapula

• Long head= the supraglenoid tubercle of the scapula, on its way there it passes through the intertubcler groove
• Short head= coracoid process of the scapula

Insertion: tuberosity of the radius

Action: flexes elbow (when hand is supinated), flexes arm at the shoulder, supinates and pronates forearm

Innervation: musculocutaneous nerve

Question 4

What is the origin, insertion, action and innervation of Brachialis

Answer 4

Origin: Humerus

Insertion: Ulnar (tuberosity and coronoid process)

Action: major flexer the elbow (because it can flex arm when hand is supinated and pronated)

Innervation: musculocutaneous nerve

Question 5

What is the origin, insertion, action and innervation of Coracobrachialis

Answer 5

Origin: coracoid process

Insertion: humerus shaft

Action: flexes and adducts the shoulder

Innervation: musculocutaneous nerve

Question 6

Be able to identify the cutaneous nerves of the anterior arm

Answer 6

I.e. look at the names

Question 7

How can you assess the fxn of the flexor digitorum profundus and/or the median nerve

Answer 7

hold the middle phalanx in full extension then have pt actively flex the distal phalanx

Question 8

Describe Trigger Finger

Answer 8

catching or locking of the involved finger flexor tendon caused by a disparity in the size between the flexor tendon and surrounding retinacular pulley system