Dislocation of the metacarpaphalangeal joint of the finger is apparently rare except in the thumb_ Closed reduction of this peculiar dislocation is usually unsuccusful.
In 197, Kaplan made a thor~zgh study of dislocations of the metacarpophalangeal joint of the index finger and emphasized that open reduction is usually necessary. He advocated a triple incision. that is, release of the-anterior fibrocartilagenous plate, the natatory ligament, and the superficial transverse metacarpal ligament, exposing the joint through a palmar approach.
In the index finger, the dislocated metacarpal head becomes firmly wedged between the fibrocartelagenous plate and the super;icial transverse metacarpal ligament. The flexor tendon traps the metacarpal head from the ulnar side and the lumbrical does so radially.
Because of the more radial course of the long flexor tendons, in the little finger the flexor ten-dons trap the metacarpal head on the radial side while the tendon of the abductor digiti minimi is the ulnar trapping element.
We experienced a case of dislocation of the metacarpophalangesl joint of the index finger and a case involving the little finger which presented an essentially similar problem. As advocated by Kaplan, a triple release was carried out with satisfactory results.
We report these rare and iatresting cases with a review of literaure.
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