Which nerve is primarily tested by the pronator teres test?

• A. Radial nerve
• B. Median nerve
• C. Ulnar nerve
• D. Musculocutaneous nerve

Answer: (B)

The pronator teres test is primarily used to assess the median nerve. This nerve is responsible for innervating not only the pronator teres muscle but also several other muscles in the forearm and hand that contribute to motor function. During the test, when resistance is applied to the pronation of the forearm, any weakness or pain experienced typically indicates a potential issue with the median nerve.

In contrast, the radial nerve primarily innervates muscles involved in extending the elbow and wrist, and is not directly associated with the action of pronation. The ulnar nerve mainly affects the muscles involved in fine motor activities of the hand and is less involved in forearm movement. The musculocutaneous nerve innervates muscles in the anterior compartment of the arm responsible for flexion at the elbow, but it does not play a significant role in the function being tested by the pronator teres test. Consequently, any testing focusing on the pronator teres is specifically indicative of the median nerve and its related functions.