Table 1.

Jahss Classifi cation System of 1st Metatarsophalangeal Joint Dislocations.³

Type I	Dorsal dislocation with no disruption of the sesamoid mass, usually irreducible on closed reduction attempts
Type 1IA	Dorsal dislocation with a rupture of the intersesamoidal ligament resulting in a wide separation of the sesamoids on the metatarsal head allowing an easier reduction to occur
Type 1IB	Dorsal dislocation with a medial sesamoid transverse fracture, usually reducible
Type III	Dorsal dislocation with the sesamoids maintaining the same anatomical position with complete ruptures of the conjoint tendons and intact sesamoids and volar plate