Correction of ulnar claw hand and Wartenberg's sign

Ulnar claw hand usually occurs when the ulnar nerve is damaged distally. Claw hand deformity is characterized by metacarpophalangeal hyperextension and interphalangeal flexion, making it impossible to oppose the fingers and thumb. Bouvier's test is used to guide the procedure. Palliative surgery requires prior preparation of paralytic hands. In case of a positive Bouvier's test, Zancolli's lasso technique is preferred because of its effectiveness. Capsuloplasty with anteroposterior transosseous fixation is used if the bone is strong enough and when flexor digitorum profondus muscle is inactive and does not allow flexor digitorum superficialis tendon transfer. In case of a negative Bouvier's test with interphalangeal extension deficit of 45° of less, direct interossei muscle restoration techniques by active transfers are performed. If the interphalangeal extension deficit is more than 45°, proximal interphalangeal arthrodesis is indicated. Wartenberg first described actively irreducible abduction of the little finger. Wartenberg's sign is seen when ulnar paralysis occurs, and during ulnar nerve regeneration. Treatment of isolated Wartenberg's sign consists of re-routing the extensor digiti minimi. Among the other techniques, Belmahi's "tie lasso" is preferred when flexible claw hand is associated with Wartenberg's sign.