Treatment of unstable dorsal proximal interphalangeal fracture/dislocations using a hemi-hamate autograft.

PURPOSE: This retrospective study was designed to evaluate the clinical and radiographic results of a hemi-hamate autograft for the treatment of comminuted dorsal proximal interphalangeal (PIP) joint fracture/dislocations.

METHODS

Thirteen consecutive patients underwent hemi-hamate autograft for the treatment of an unstable dorsal PIP fracture dislocation. The fractured middle phalangeal base was debrided and the defect was replaced using a size-matched portion of the dorsal/distal hamate osteoarticular surface and was secured with miniscrews. The average middle phalangeal volar lip involvement on initial radiographs was 60% (range, 40% to 80%). The average time to surgery was 45 days (range, 2-175 d). Range of motion, stability, and grip strength were measured at a mean follow-up evaluation of 16 months. Radiographs were evaluated for union, graft incorporation, and/or collapse. Subjective data, satisfaction, and return to work were obtained on 12 of the 13 patients at a mean follow-up evaluation of 17 months.

RESULTS

The average arc of motion at the PIP joint was 85 degrees (range, 65 degrees to 100 degrees ). The distal interphalangeal (DIP) joint average arc of motion was 60 degrees (range, 35 degrees to 80 degrees ). Average grip strength was 80% of the uninjured side. Bony union was achieved in all patients. One graft showed ulnar collapse but graft resorption was not noted. Except for 2 patients with recurrent dorsal subluxation there were no complications. The average pain level was 1.3 (as rated on a visual analog scale of 0-10). Eleven of 12 patients were very satisfied with their function and one was somewhat satisfied; one patient was lost to follow-up.

CONCLUSIONS

When greater than 50% of the volar base of the middle phalanx is fractured in a PIP fracture/dislocation or the joint remains unstable despite a lesser degree of involvement, a hemi-hamate autograft should be considered. This procedure reconstructs the cup-shaped contour of the middle phalangeal articular surface and facilitates a stable, functional arc of motion at the PIP joint. Additionally, in our experience the procedure renders minimal disability and has a low complication rate.