[Treatment of chronic scapholunate dissociation using Cuénod's bone-ligament-bone autograft]

Abstract

Objective: Correction of chronic scapholunate dissociation by replacement of the biomechanically most important dorsal part of the scapholunate ligament using a bone-ligament-bone autograft taken from the carpometacarpal joint II and, additionally, a modified dorsal capsulodesis.

Indications: Nonfixed chronic scapholunate dissociation without useful remnants of the ligament in which loss of the dorsal part of the scapholunate ligament is the crucial pathophysiological moment.

Contraindications: Chronic scapholunate dissociation with fixed deformity. Osteoarthritis.

Surgical technique: Dorsal incision. Approach to the wrist using the capsular flap described by Berger. Reduction of deformity and temporary transfixation of the scaphoid to the capitate as well as to the lunate. Creation of a trough at the ulnar edge of the dorsal aspect of the scaphoid and another trough at the radial edge of the dorsal aspect of the lunate. Fixation of an exactly fitting bone-ligament-bone autograft taken from the trapezoidometacarpal joint II with 1.2-mm screws into the troughs. Fixation of a part of the dorsal intercarpal ligament which is based on the scaphoid to the lunate using a bone anchor.

Postoperative management: Immobilization using a below-elbow cast including the metacarpophalangeal joint of the thumb for 8 weeks; removal of Kirschner wires 10 weeks postoperatively; after Kirschner wire removal physiotherapy to improve range of motion.

Results: Twelve out of 16 male patients were available for a clinical and radiologic examination after a mean follow-up time of 6.3 years (minimum 1.6, maximum 7.3 years). Clinical results were excellent. The modified Mayo Wrist Score averaged 87 points (minimum 65, maximum 100 points). Eleven patients had an excellent or good result, none of the patients showed a poor result. The DASH Score (Disability of the Arm, Shoulder and Hand) was 13 points on average (minimum 0, maximum 42 points). All patients would have the same operation again. Radiologically, a stretching of the bone-ligament-bone autograft was found in six cases. A symptomatic SLAC (scapholunate advanced collapse) wrist with the need for a salvage operation could not be observed.