Perioperative axial loading computed tomography findings in varus ankle osteoarthritis: Effect of supramalleolar osteotomy on abnormal internal rotation of the talus

Abstract

BackgroundWe used axial loading computed tomography (AL CT) to evaluate preoperative and postoperative talocrural joints of patients who underwent supramalleolar osteotomy (SMO) to treat varus ankle osteoarthritis. MethodsWe performed retrospective analyses of 16 patients (18 feet) who underwent SMO including fibular osteotomy. Radiographic assessment was performed with weightbearing radiographs and AL CT. Clinical outcomes were assessed based on American Orthopedic Foot & Ankle Society (AOFAS) scale, visual analog scale (VAS) for pain, and Foot and Ankle Ability Measure (FAAM). ResultsThe mean 2-year follow-up tibial-ankle surface angle, talar tilt angle, Takakura stage, and tibial-lateral surface angle were all significantly different relative to preoperative parameters (P<.05). The mean 6-month follow-up talus rotation ratio was significantly corrected compared to the preoperative value (P=.001). The mean 2-year follow-up AOFAS, VAS at gait, and FAAM scores were all significantly improved relative to preoperative measurements (P=.001). ConclusionsAbnormal internal rotation of the talus in mild to moderate varus ankle osteoarthritis found on AL CT was significantly corrected after SMO. Level of evidenceTherapeutic Level IV