Intraosseous blood supply of the capitate and its correlation with aseptic necrosis.

Isolated capitate fractures that result in the development of aseptic necrosis of the proximal pole are uncommon. Five patients were treated who developed aseptic necrosis of the proximal pole. Four had a history of trauma with radiographic evidence of nonunion. In vitro arterial injection studies were done to correlate clinical problem with intraosseous capitate vascularity. Palmar vessels were found to contribute the majority of the blood supply to the capitate. Three patterns of intraosseous blood supply were seen. In each pattern, the proximal pole received its blood supply exclusively in a retrograde fashion across the capitate waist analogous to the proximal scaphoid. Aseptic necrosis without collapse of the proximal pole was successfully managed with curettage and bone grafting in three patients. The remaining two patients, with collapse and pericapitate degenerative changes, were managed with intercarpal fusion.