Irreducible dislocation of the metatarsophalangeal joints of the foot.

An unusual dislocation of the metatarsophalangeal joints of the third, fourth, and fifth toes with fractures of the neck of the second metatarsal bone occurred in a 23-year-old man. Hyperextension of the metatarsophalangeal joints is the mechanism of injury and is substantiated by the anatomic investigation. The metatarsal head is trapped between the fibrocartilaginous plate on the plantar surface of the foot, the dorsal capsule and deep transverse metatarsal ligament on the dorsal surface, the flexor tendons on the lateral aspect and the lumbrical tendons on the medial aspect. Division of the fibrocartilaginous plate, the deep transverse ligament and the dorsal capsule facilitates reduction of dislocation.