Which statement best describes the pronator teres test?

• A. It tests median nerve entrapment
• B. It tests ulnar nerve entrapment
• C. It tests radial nerve entrapment
• D. It tests axillary nerve entrapment

Answer: (A)

The main idea is to detect compression of the median nerve as it passes through the pronator teres in the forearm. In this test, the elbow is flexed about 90 degrees and the forearm is held in a position that allows pronation to be resisted. When the patient pronates against resistance, if numbness or tingling appears in the median nerve distribution (the lateral palm and the palmar aspects of the thumb, index, middle, and half of the ring finger), it suggests entrapment of the median nerve at the pronator teres (pronator teres syndrome). The test works because squeezing the nerve between the two heads of the pronator teres during resisted pronation provokes symptoms from the affected segment of the nerve.

This is the best description because other nerves are tested with different provocative maneuvers and would produce symptoms in their own distinct distributions (ulnar nerve entrapment at the elbow would show ulnar-innervated finger symptoms and be tested with signs like Tinel’s at the elbow; radial nerve issues affect extension and dorsal hand sensation; axillary nerve issues involve the deltoid and shoulder region).