Clinical and radiologic evaluation of medial epicondylar osteotomy for varus total knee arthroplasty

Abstract

BackgroundIn varus total knee arthroplasty (TKA), a pathologic contracture of the medial soft tissue should be released for ligament balancing. A medial epicondylar osteotomy has been performed as an alternative method for this. The purpose of this study was to demonstrate the clinical and radiologic results of medial epicondylar osteotomy for varus TKA, focusing on the union type of osteotomy site. MethodsThe study retrospectively evaluated 61 cases with a mean femorotibial angle of 10.4° varus and a mean flexion contracture angle of 8.5±9.8°. Intraoperative medial and lateral gap difference in extension and 90° flexion was accepted at <2mm. Clinical outcomes (Knee Society Scores, range of motion) and radiologic outcomes (coronal alignment and valgus stability) were compared between the two groups divided by the union type of osteotomy site (bony union or fibrous union). ResultsThe clinical and radiologic outcomes were significantly improved at the latest follow-up. Bony union was achieved in 39 (63.9%) patients, whereas 22 patients showed fibrous union. There was no difference in the varus–valgus angle on the stress radiographs between the bony union and fibrous union group (1.6±1.2° vs. 1.6±0.8°, P<0.916). The Knee Society Scores (knee, function), range of motion and radiographic alignment did not differ between the two groups. ConclusionMedial epicondylar osteotomy was a good option for gap balancing during TKA, as it provided satisfactory clinical and radiological results, regardless of union type of the osteotomy site.