Recognition and treatment of uncommon carpal fractures.

Fractures of the trapezial ridge, hamate hook, and pisiform are often due to isolated, direct injury, but other carpal bone fractures are seldom isolated injuries. Midcarpal fractures should stimulate a search for associated perilunate injury; distal carpal row fractures suggest carpometacarpal fracture--dislocations or subluxations. Crush injury with fracture of the hamate, triquetrum, or trapezium may indicate an axial subluxation of the ulnar or radial carpus. Bone scans can be useful as a screening tool. Diagnosis will often require special radiographic techniques such as tomography. Carpal bone fractures are usually intra-articular, and treatment should be aimed at restoring joint congruity. Small extra-articular fractures and injuries to the pisiform can be successfully treated with excision.