Dislocation of the extensor tendons over the metacarpophalangeal joints.

Twenty-seven patients who had received treatment for dislocation of the extensor tendons over the metacarpophalangeal joint were reviewed. Sixteen patients had traumatic dislocations, seven had spontaneous dislocations, and four had congenital dislocations. The long finger was most frequently affected. The other fingers were affected almost equally. Displacement of the extensor tendon always occurred in the ulnar direction in the long and ring fingers. The index and little fingers exhibited different patterns of dislocation: two patients had ulnar dislocation of both the common and proprius tendons, and the remaining five patients had divergent dislocation of the two tendons. Nonsurgical treatment was undertaken in six cases. Surgery was performed in 21 cases. No recurrent dislocations were reported in any of the patients. Based on our experience, patients seen within 2 weeks of injury initially should be treated with splinting of the involved metacarpophalangeal joint. Chronic dislocations should be treated with a primary repair of the defect in the sagittal band. When the sagittal band is absent or deficient, the tendon must be stabilized using a loop procedure with a tendon slip.