Phalen’s test is used to diagnose which condition?

Phalen’s test is used to diagnose which condition?

• A. Pronator syndrome
• B. Thoracic outlet syndrome
• C. Cubital tunnel syndrome
• D. Carpal tunnel syndrome

Answer: (D)

Phalen’s test works by increasing pressure on the median nerve at the carpal tunnel through sustained wrist flexion. When the wrists are fully flexed, the densities within the carpal tunnel compress the median nerve, and if there is carpal tunnel syndrome, the patient typically experiences numbness or tingling in the median nerve distribution (thumb, index, middle finger, and the radial side of the ring finger) within about a minute. This direct link between wrist flexion, carpal tunnel pressure, and median-nerve symptoms makes the test specific for carpal tunnel syndrome. The other conditions involve different nerves or locations of compression. Pronator syndrome is a proximal median nerve issue in the forearm, which wouldn’t reliably reproduce carpal-tunnel–type symptoms with mere wrist flexion. Cubital tunnel syndrome affects the ulnar nerve at the elbow, so symptoms appear in the ulnar distribution rather than the median pattern. Thoracic outlet syndrome involves compression higher up in the thoracic outlet and produces a broader set of vascular or neurogenic signs that aren’t specifically tied to the median nerve symptoms elicited by Phalen’s maneuver.

Phalen’s test works by increasing pressure on the median nerve at the carpal tunnel through sustained wrist flexion. When the wrists are fully flexed, the densities within the carpal tunnel compress the median nerve, and if there is carpal tunnel syndrome, the patient typically experiences numbness or tingling in the median nerve distribution (thumb, index, middle finger, and the radial side of the ring finger) within about a minute. This direct link between wrist flexion, carpal tunnel pressure, and median-nerve symptoms makes the test specific for carpal tunnel syndrome.

The other conditions involve different nerves or locations of compression. Pronator syndrome is a proximal median nerve issue in the forearm, which wouldn’t reliably reproduce carpal-tunnel–type symptoms with mere wrist flexion. Cubital tunnel syndrome affects the ulnar nerve at the elbow, so symptoms appear in the ulnar distribution rather than the median pattern. Thoracic outlet syndrome involves compression higher up in the thoracic outlet and produces a broader set of vascular or neurogenic signs that aren’t specifically tied to the median nerve symptoms elicited by Phalen’s maneuver.