Luxation dorsale complexe de la métacarophalangienne des doigts longs – quels résultats ?

Dislocation of the metacarpophalangeal joint of long fingers is a rare pathology. Dorsal metacarpophalangeal joint dislocation typically occurs from forced hyperextension. Closed reduction is possible for simple dislocations but open reduction is usually required for complex dislocations. Soft tissue interposition and button hole entrapment of the metacarpal head are associated with complex dislocations and require particular attention in open reduction. The purpose of this study was to describe the long term follow-up of 4 patients and to review the literature concerning follow-up and complications. We reviewed the cases of 4 patients with isolated dorsal dislocation of the metacarpophalangeal joint who were available for long-term follow-up. The study included age, sex, and dominant hand, number of reduction attempts, time from injury to operation, surgical approach, intraoperative findings, and length of immobilization postoperatively. The QuickDASH and the range of motion of the metacarpophalangeal joint and grip strength were measured. X-rays were realized. The dislocation concerned the metacarpophalangeal joint of the little finger in two cases and the index finger in two others. The median follow-up was 8 (range, 5–11) years. All patients reported full function of the hand, a mild loss of MPJ flexion was noted in 1 patient. Grip strength was reduced in 2 patients. The mean QuickDASH score was 4 (range, 0–20). No osteoarthritis changes were found on X-ray. The review of literature found that the most of the articles describing this injury did not report long-term follow-up and indicates that complications in patients with complex dorsal metacarpophalangeal joint are related to failure of diagnosis, multiple attempts at closed reduction, traumatic open reduction, or prolonged immobilization, and may result in joint stiffness, early degenerative arthritis, or osteonecrosis of the metacarpal head, pain, premature epiphysis closure, and metacarpal shortening. The complex dorsal MPJD is a rare injury, if treated on the day of injury with dorsal or volar open reduction techniques and short lenght immobilization, it can results in a good outcome.