Froment's Sign | Rationale & Interpretation

The video tutorial explains Froment's sign, a test for diagnosing ulnar nerve palsy. It covers the procedure for both negative and positive test results, highlighting the role of the lateral prehensile grip and thumb interphalangeal joint. A positive test indicates compensation due to weakness in the adductor pollicis muscle, often caused by ulnar nerve damage. The tutorial also discusses the involvement of the flexor pollicis longus muscle and the lack of psychometric data for Froment's sign.

What is the primary purpose of the Froment's sign test?

• To assess the strength of the biceps muscle

• To evaluate shoulder mobility

• To diagnose carpal tunnel syndrome

• To diagnose ulnar nerve palsy

In a negative Froment's sign test, what is observed?

• Compensation by the flexor pollicis longus

• Maintenance of the lateral prehensile grip

• Massive flexion at the thumb's interphalangeal joint

• Loss of grip on the paper

What indicates a positive Froment's sign during the test?

• The paper is not pulled away

• The thumb's interphalangeal joint remains neutral

• Flexion at the thumb's interphalangeal joint

• The patient uses both hands

Which muscle is primarily weakened due to ulnar nerve damage, leading to a positive Froment's sign?

• Biceps brachii

• Flexor pollicis longus

• Adductor pollicis

• Triceps brachii

Which nerve innervates the muscle that compensates during a positive Froment's sign?

• Ulnar nerve

• Radial nerve

• Median nerve

• Sciatic nerve