Background: The aim of this study was to evaluate the clinical and radiologic outcomes of medial compartment ankle osteoarthritis after supramalleolar osteotomy (SMO) without the bone marrow stimulation procedure and confirm cartilage recovery by second-look arthroscopy.
Methods: Twenty-two ankles that were followed for more than 1 year after SMO were retrospectively reviewed. Visual analog scale pain scores and American Orthopaedic Foot & Ankle Society ankle-hindfoot scores were used for functional evaluations. The tibial anterior surface angle and tibial lateral surface angle were measured on radiographs, and ankle osteoarthritis was classified by Takakura stage. Among the 22 patients, 21 underwent ankle arthroscopy prior to SMO, and second-look arthroscopy was performed in 16 patients 1 year postoperatively. Tibiotalar cartilage regeneration was evaluated according to the modified Outerbridge classification for the 14 patients who had undergone SMO without the bone marrow stimulation procedure.
Results: The mean visual analog scale and American Orthopaedic Foot & Ankle Society scores significantly improved from 6.5 preoperatively to 1.1 postoperatively and from 60.7 preoperatively to 87.1 postoperatively, respectively ( P < .05). The mean tibial anterior surface and tibial lateral surface angles significantly improved from 83.5° and 76.9° preoperatively to 93.8° and 80.2° postoperatively, respectively ( P < .05). All preoperative Takakura stage IIIa cases and IIIb case improved to postoperative stage II. On second-look arthroscopy, cartilage regeneration of the medial compartment of the tibiotalar joint was observed in 12 of 14 patients (85%), whereas cartilage deterioration was not observed in any patient.
Conclusions: SMO without the bone marrow stimulation procedure for medial ankle osteoarthritis demonstrated cartilage regeneration in the medial tibiotalar joint in most patients by second-look arthroscopy, as well as satisfactory clinical and radiologic outcomes.
Level of evidence: Level IV, case series.
Keywords: arthritis; cartilage regeneration; second-look arthroscopy; supramalleolar osteotomy.