Froment sign is a special test of the hand for weakness of the ulnar nerve, specifically, the action of adductor pollicis. __TOC__ Process of examination A patient is asked to pinch an object, usually a flat object such as a piece of paper, between the thumb and index finger (pinch grip). The examiner then attempts to pull the object out of the subject's hand.Jeff G. Konin et al. Special Tests for Orthopedic Examination: Third Edition. Thorofare, NJ. SLACK Incorporated, 2006. A person with notable weakness of the adductor pollicis due to advanced ulnar neuropathy will flex the thumb using the flexor pollicis longus.Richardson, Craig and Fabre, Gerd. '"Froment's Sign." Journal of Audiovisual Media in Medicine. Vol. 26, No. 1 (2003):34. Froment sign is the flexion of the interphalangeal joint of the thumb rather than adduction of the entire thumb. The flexor pollicis longus is nearly always innervated by the anterior interosseous branch of the median nerve. Simultaneous hyperextension of the thumb MCP joint is indicative of ulnar nerve compromise. This is also known as Jeanne's sign.
Eponym It is named after French neurologist Jules Froment.
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