Joint-Preserving Osteotomy of the Lateral Tibial Plafond for Posttraumatic Osteonecrosis: A Prospective Cohort Study.

BACKGROUND: Posttraumatic osteonecrosis (ON) of the lateral distal tibia is a rare but severe complication of malleolar fractures. Treatment options include ankle fusion, arthroplasty, osteotomy, and drilling but clinical data on outcomes are limited to single case reports. The aim of this study was to prospectively evaluate the outcome following joint-preserving reconstruction.

METHODS: Over a 10-year period, 10 patients (8 females and 2 males, average age 36 years; range, 27-68 years) with posttraumatic ON were treated with intra-articular osteotomy of the distal tibia and bone grafting. All patients initially sustained a closed pronation injury, 7 with initial tibiotalar subluxation. Chronic syndesmotic instability following initial treatment was present in 4 patients and 5 were smokers. All patients were followed for a median of 68 (range, 12-103) months, 7 returned in person for clinical and radiographic follow-up.

RESULTS: No immediate postoperative complications were seen. Secondary ankle fusion was necessary in 1 case (10%) because of progressive osteoarthritis. At the time of follow-up, anterior ankle arthritis leading to impingement and requiring cheilectomy was noted in 4 cases, partial graft necrosis, and secondary syndesmotic instability requiring revision surgery was seen in 1 case each. Compared with the preoperative values, significant improvement in the Olerud-Molander Ankle Score ( P  = .012), EuroQuol-5 Score ( P  = .008), and Foot Function Index (FFI-D pain, P  = .028; FFI-D restriction, P  = .038) was seen. Average range of motion at the ankle was 45 degrees.

CONCLUSION: In our limited series of patients with posttraumatic ON of the lateral distal tibia, we found that joint-preserving reconstruction using an intra-articular distal tibial osteotomy with autologous bone grafting usually provided significant functional improvement and pain relief. In our cohort secondary fusions by a median 5.5-year follow-up were rare, but secondary, joint-sparing surgeries were common.

LEVEL OF EVIDENCE: Level III, prospective study.