Claw hand is caused by:
(Ulnar nerve) Ref: 174-BDC-l, 242, 342-Appley* The most common are drop wrist and drop fingers - Radial nerve palsy* Siamian thumb and pointing index finger - Median nerve palsy* Partial cloud hand -- ulnar nerve palsy* Complete claw hand - ulnar and median nerve palsyUlnar nerve lesions(A) Low ulnar nerve palsy: Intrinsic muscle wasting, in the ring and little fingers in the knuckle joints are hyperextended (paralysed lumbricals) and the interphalangeal joints are flexed (paralysed interossei)(B) High ulnar nerve palsv: Profundus action is lost so the terminal interphalangeal joints are not flexed (ulnar paradox)Fromet's sign - Finger abduction is weak and this together with loss of thumb adduction, makes pinch difficult. The patient is asked to grip a sheet of paper forcefully between thumb and index fingers. While the examiners tries to pull it away: powerful flexion of the thumb interphalangeal joint signals weakness of adductor pollicis and over compensation by the flexor pollicis longus.
Median nerve palsy
Ulnar nerve palsy
Radial nerve palsy
Anterior interroseus nerve
Upper Extremity