Irreducible dorsal dislocation of the interphalangeal joint of the great toe.

A 54-year-old man had an irreducible dorsal dislocation of the interphalangeal (IP) joint of the great toe, and injury that seems not to have been previously reported in the literature. The stability at the IP joint afforded by collateral ligaments, tendons, and plantar accessory ligament along with the short level arm of the distal phalanx normally resists dislocation. A strong dorsiflexion force to this joint with the foot and metatarsophalangeal joint fixed in a weight-bearing position is necessary to produce this injury. Treatment should begin with attempted closed reduction, but if this proves unsuccessful, an invaginated volar plate may be preventing reduction, in which case open reduction will be required. A dorsal approach affords easy exposure. Once the volar plate is reflected plantarward, the joint is easily reduced. Neither repair of the volar plate nor prolonged immobilization is necessary. At 15-month follow-up, our patient had no residual instability.