Plate Fixation of Hamate Fractures in Fourth and Fifth Carpometacarpal Fracture Dislocations.

Abstract

Traumatic dislocations of the fourth and fifth metacarpals, in conjunction with dorsal hamate fractures, are a common entity that can lead to the instability of the fourth and fifth carpometacarpal (CMC) joints. The fracture of the hamate, usually in a coronal dorsal shear configuration, can lead to the dorsal subluxation of the hamatometacarpal joint. Open reduction and internal fixation of the hamate bone with a dorsally applied buttress plate can re-establish a stable and congruent joint surface and anatomically align the articular surfaces of the small and ring finger CMC joints. We present a technique of internal fixation of the hamate to facilitate the reduction of the hamatometacarpal joints. Using a dorsal approach centered over the fourth and fifth CMC joints, the joint surfaces are directly visualized and subsequent fixation of the hamate is performed using a 1.3-mm T-plate to securely buttress its articular surface. This technique presents an approach to the multifaceted injury pattern of fourth and fifth CMC dislocations associated with a hamate fracture.