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

Froment's sign is utilized to evaluate the functionality of the adductor pollicis muscle, which is primarily responsible for adducting the thumb. This test is particularly relevant in assessing ulnar nerve function. During the test, the patient is asked to hold a piece of paper between the thumb and index finger while the examiner tries to pull the paper away. A positive Froment's sign occurs when the patient flexes the thumb at the interphalangeal joint due to the weakness of the adductor pollicis, indicating ulnar nerve compromise or dysfunction.

The other tests mentioned in the question serve different purposes. Phalen's test is designed to assess for carpal tunnel syndrome by evaluating median nerve compression. Tinel's sign is another test for carpal tunnel syndrome, measuring the sensitivity or pain along the median nerve as it traverses the wrist. The grip strength test evaluates overall hand strength but does not specifically isolate the function of the adductor pollicis. Thus, Froment's sign is the appropriate choice for assessing the functionality of this specific muscle.