Question

A man suffers a penetrating wound through the anterior axillary fold, with resulting damage to one of the main terminal branches of the brachial plexus. Among the effects is a significant weakening of flexion of the elbow. One or more other effects to be expected is (are):______.

A. Loss of cutaneous sensation on the tips of several fingers.
B. Weakening of flexion at the shoulder and loss of cutaneous sensation on the anterolateral surface of the forearm.
C. Only weakening of flexion at the shoulder.
D. Weakening of flexion at the shoulder and loss of cutaneous sensation on the anterolateral surface of the arm.

Answer 1

The correct answer is option b. Weakening of flexion at the shoulder and loss of cutaneous sensation on the anterolateral surface of the forearm.

Step-by-step explanation:

Brachii and brachialis are the two muscles that are innervated by the Musculocutaneous nerve. These muscles help in the production of the flexion at the elbow, and it is known that the musculocutaneous nerve is damaged due to the penetration through the anterior axillary fold.

Other than these muscles there would be an effect on the nerve that provides sensory signals or information to the anterolateral surface of the forearm, known as the lateral antebrachial cutaneous nerve.

Thus, the correct answer is: option B.