Fracture of the hook of the hamate.

Three patients with hamate hook fractures were evaluated. These fractures were difficult to diagnose clinically and radiographically. Mechanisms of injury reported in the literature include blunt trauma to the hamulus or pisiform, forceful swinging of a grasped object, or a forceful muscular contraction. Delayed diagnosis may result in late complications including carpal tunnel syndrome, flexor tendon rupture, ulnar nerve palsy, or ulnar artery compromise. Pain when grasping or swinging an object is often a clue to the correct diagnosis. Normal standard and carpal tunnel views do not exclude this injury. Tomography may be necessary for radiographic detection and permits detailed evaluation of fracture margins. Pertinent carpal anatomy is reviewed.