Medial Open-Wedge Supramalleolar Osteotomy for Patients with Takakura 3B Ankle Osteoarthritis: A Mid- to Long-Term Study

It is controversial whether supramalleolar osteotomy is suitable for Takakura Stage 3B osteoarthritis or not. The aim of this study was to evaluate the outcomes of supramalleolar osteotomy in patients with Takakura 3B osteoarthritis. From February 2008 to August 2013, supramalleolar osteotomy was performed in 21 patients matching the inclusion criteria. The mean patient age at operation was 53.7±5.8 years (range: 39 to 61 years). The mean duration of follow-up was 87.7±19.5 months (range: 61 to 125 months). The radiologic evaluation included the tibial articular surface (TAS) angle, tibial lateral surface (TLS) angle, and talar tilt (TT) angle. Functional assessment was performed with use of the AOFAS, VAS, SF-36, and AOS. All patients were followed. TAS angle improved from 82.8±2.4 to 90.3±2.3. TLS angle changed from 77.5±2.8 to 79.4±2.7. The preoperative TT angle and postoperative TT angle were 13.4±3.6 to 4.8±3.6, respectively. For functional evaluation, the preoperative VAS and AOFAS-AH scores were 5.7±1.3 and 48.0±15.8, while the postoperative VAS and AOFAS-AH scores were 2.5±1.9 and 74.8±11.5. The mean SF-36 scale improved from 41.2±13.1 to 66.7±14.9. The AOS score improved from 61.4±12.5 to 27.5±17.8. 1 patient underwent total ankle replacement 3 years postoperatively. 4 patients remained stage 3B including the TAR one. 4 improved to stage 3A, 11 improved to stage 2, and 2 improved to stage 1. Supramalleolar osteotomy combined with auxiliary procedures can restore the malalignment of ankle joint and modify the abnormal stress distribution so as to achieve functional improvement and improve radiographic stages.