Modified Hemihamate Arthroplasty With Oblique Osteotomy of the Middle Phalanx Base to Reconstruct Proper Contour of...

Treatments of unstable dorsal fracture dislocations of the proximal interphalangeal (PIP) joint are very challenging. The authors performed modified hemihamate arthroplasty for these injuries in 13 patients (13 fingers). Our surgical technique was unique in the point that we put volarly oblique osteotomy in the coronal plane at the recipient site to create an adequate reconstruction of the volar lip of the articular surface of the middle phalanx. Affected fingers are index in 2, middle in 4, ring in 3, and little in 3, and the mean duration of follow-up was 14 months. Hemihamate arthroplasty was indicated if >30% to 50% of the volar articular surface of the middle phalangeal base showed comminuted fracture which was not large enough to allow open reduction and internal fixation. The average range of motion of the PIP joint was 17.7 degrees preoperatively, which was improved significantly to 71.3 degrees at final follow-up. Radiographically, all grafts were united but 1 showed mild graft absorption. Ten patients demonstrated normal joint space and other 3 showed mild degenerative change of PIP joints. Eleven patients showed good congruency of the PIP joint and other 2 demonstrated slight dorsal subluxation. Four patients complained of mild pain in flexion, but other 9 had no pain at all. The modified hemihamate arthroplasty is a reliable technique to treat comminuted dorsal fracture dislocations of the PIP joint.