TBL 6 Objectives

Question 1

Describe the antebrachial fascia and bicipital aponeurosis

Answer 1

The antebrachial fascia is continuous with the brachial fascia superior to it and also continues into the palm as the palmar fascia.

The bicipital aponeurosis reinforces the brachial and antebrachial fasciae covering the cubital fossa, a depression on the anterior aspect of the elbow.

Question 2

Describe the palmar fascia and aponeurosis

Answer 2

Palmar fascia is continuous with the antebrachial fascia superior to it and is thickened centrally as the palmar aponeurosis.

Question 3

Cite origins and distributions of designated cutaneous nerves

Answer 3

Lateral cutaneous nerve of the forearm

• from the musculocutaneous nerve
• supplies skin of the anterolateral forearm to wrist

Medial cutaneous nerve of the forearm

• from the medial cord
• supplies skin of the anteromedial forearm to wrist

Posterior cutaneous nerve of the forearm

• from the radial nerve
• supplies skin of the posterior forearm to wrist

Superior lateral cutaneous nerve of the arm

• from the axillary nerve
• supplies skin of the lower part of the deltoid and the lateral side of the mid arm

Medial cutaneous nerve of the arm

• from the medial cord
• supplies skin of the medial aspect of the arm

Question 4

Summarize drainage of the dorsal venous network of the hand

Answer 4

The lateral aspect of the dorsal venous network drains into the cephalic vein. The cephalic vein then ascends laterally to the deltopectoral groove where it pierces the axillary fascia and joins the axillary vein.

The medial aspect of the dorsal venous network drains in the basilic vein. The basilic vein pierces the brachial fascia and ascends medially to join the axillary vein.

Question 5

How are the median nerve and brachial artery somewhat protected when the median cubital vein is used for venipuncture?

Answer 5

The median cubital vein crosses the bicipital aponeurosis, which separates it from the underlying brachial artery and median nerve. The bicipital aponeurosis provides some protection to the artery and nerve.

Question 6

Compare the ulnar head and radial styloid process

Answer 6

The large styloid process of the radius extends farther distally than the head of the ulnar; thus, only the radius contributes to the wrist joint.

Question 7

Define the function of the interosseous membrane

Answer 7

The interosseous membrane interconnects the radius and ulna. It distributes forces received by the radius from the hand to the ulna and humerus.