Complex dislocations of the metacarpophalangeal joint.

A dorsal longitudinal incision provides excellent exposure for reducing complex dislocations of the metacarpophalangeal joints of the thumb and index finger. Within the past four years, we have successfully treated five patients with irreducible dislocations of the metacarpophalangeal joint of the thumb and four with dislocations of the index finger by open reduction through a dorsal incision. This approach exposes the joint and the major structure blocking reduction, the volar plate. The digital nerves, which are tented volarly over the metacarpal head, are not prone to injury and osteochondral fracture fragments can be easily removed from the joint. All of the dislocations were stable following reduction.