A simplified technique for treating the complex dislocation of the index metacarpophalangeal joint.

The volar approach to open reduction of the complex dislocation of the index metacarpophalangeal joint as described by Kaplan proved to have certain disadvantages. Digital nerves are easily damaged during exposure and there is a limited view of the entrapped fibrocartilaginous volar plate dorsal to the metarcarpal head. A direct dorsal longitudinal incision through the skin and extensor tendon gives full exposure. The volar plate attached to the proximal phalanx and trapped over the dorsal aspect of the metacarpal head is in full view. The volar plate is split longitudinally and the dislocation reduces spontaneously as the flexor tendons and lumbrical muscle slip by the metacarpal head. The advantages of this approach as compared with the volar approach are: (1) there is full exposure of the fibrocartilaginous volar plate, the main structure blocking reduction; (2) digital nerves are not as apt to be damaged; and (3) accurate reduction and fixation of the osteochondral fracture of the metacarpal head, frequently seen with this dislocation, is possible.