Combined supramalleolar osteotomy and ankle arthrodesis for end-stage ankle arthritis with large varus deformity

This study aimed to report our experience with the combined use of hemiwedge supramalleolar osteotomy (SMO) procedure and open ankle arthrodesis (AA) for correcting end-stage ankle arthritis with large varus deformity in the same operative session.

This retrospective study prospectively followed 14 consecutive patients (15 ankles), consisting of 5 men and 9 women, with a mean age of 68.3 years, and underwent SMO/AA for treating end-stage ankle arthritis and varus deformity of the hindfoot of ≥ 15° from April 2019 to June 2023. The participants were followed up for a mean duration of 3.4 years.

All patients experienced pain relief and walking ability improvement after SMO/AA. The mean osteotomy wedge height was 7.0 mm. The mean time to full-weight bearing and bone union time was 8.4 weeks and 11.7 weeks, respectively. The mean visual analog scale and the Japanese Society for Surgery of the Foot scale score significantly improved from 7.3 and 51.9 preoperatively to 1.4 and 82.2 postoperatively, respectively (p < 0.001). Further, the Self-Administered Foot Evaluation Questionnaire was significantly improved on all subscales (p < 0.001). The mean hindfoot alignment angle significantly decreased from 22.5° preoperatively to 1.8° postoperatively (p < 0.001). Complications included secondary subtalar joint arthritis in two, asymptomatic stress fracture of the calcaneus in one, and delayed union of the osteotomy site in one patient.

Combined SMO/AA is a potential option for preserving the subtalar joint in treating end-stage ankle arthritis with large varus deformity. This technique successfully corrects ankle/hindfoot varus deformity and preserves leg length and subtalar joint motion. Further, a single lateral incision minimizes the risk of impaired blood supply. One-stage surgical treatment reduces recovery time, hospitalization duration, and surgical cost. Rigid locking fixation with careful postoperative weightbearing is required to attain uneventful bone healing.

IV.