What test is used to assess the functionality of the adductor pollicis?

Froment's sign is the test used to assess the functionality of the adductor pollicis muscle. This muscle is innervated by the ulnar nerve and is responsible for the adduction of the thumb. During the test, the patient is asked to hold a piece of paper between their thumb and index finger while the examiner attempts to pull the paper away. If the adductor pollicis is functioning properly, the patient should be able to maintain a firm grip without flexing their thumb.

A positive Froment's sign indicates that the adductor pollicis is not functioning effectively, often compensating with flexor pollicis longus, which is innervated by the median nerve. This can suggest ulnar nerve neuropathy or dysfunction.

In contrast, Phalen's test evaluates for carpal tunnel syndrome by assessing for numbness or tingling in the distribution of the median nerve when the wrists are flexed. Tinel's sign, on the other hand, involves tapping over the median nerve at the wrist to elicit similar symptoms indicative of nerve irritation from carpal tunnel syndrome. The grip strength test measures overall hand strength but does not specifically isolate the functionality of the adductor pollicis.