Long-term preservation of metacarpophalangeal joint function in traumatic defects by metatarsophalangeal osteochondral transplantation.

Introduction: The integrity of the metacarpophalangeal (MCP) joints is essential for finger and hand function. Preservation of range-of-motion is one of the aims in reconstruction of complex injuries to these joints. Osteochondral transplants have shown to be reliable in reconstruction of various joint defects. This series presents three patients with traumatic injuries to four MCP joints, which were reconstructed by seven avascular osteochondral transplants of metatarsophalangeal (MTP) joints. The joints were examined for radiographic signs of resorption or joint space narrowing, and if this would affect the joints' function in the long term.

Methods: In three patients (40, 45 and 48 years) with complex injuries to their MCP joints (one milling, two saw injuries), four joints were reconstructed by three metatarsal head and four osteochondral transplants of the base of the proximal toe phalanges. Beside the joint itself, various soft tissue defects were reconstructed in each patient. The patients were clinically and radiographically examined after 9, 6, respectively, 7 years.

Results: All patients were satisfied with the result without any pain in the MCP joints. Range-of-motion in the four affected joints rated 25, 60, 75, and 80°, DASH scores rated 13, 29, and 17, respectively. None of the patients complained of problems at their feet. Radiographic examination revealed moderate joint space narrowing in one of the four joints. In another patient, localized osteolysis was found around the screws' heads, so that the screws were removed 7 years post-op.

Conclusions: Osteochondral transplants for reconstruction of MCP defects are able to preserve function in severely injured joints even in the long term. Joint space narrowing may occur, which is not accompanied by pain, however. Since localized osteolysis can cause screw head prominence, mid-term radiographic follow-up is necessary to prevent damage to the joint. In the long term, remaining bone stock may be adequate for total joint replacement.