Abstract
Medial opening wedge high tibial osteotomy (MOWHTO) is a knee-preserving surgical option for selected patients with symptomatic medial compartment osteoarthritis (OA) and varus malalignment. Successful outcomes depend on appropriate patient selection, accurate radiographic assessment, individualized correction planning, stable fixation, and careful intraoperative protection of the lateral hinge and posterior neurovascular structures. This educational review summarizes the practical steps in the evaluation and surgical planning of MOWHTO, including clinical assessment, classification of varus deformity, imaging, indications and contraindications, correction target, osteotomy orientation, hinge position, fixation options, bone grafting, drain use, and postoperative considerations. The review also compares MOWHTO with lateral closing wedge high tibial osteotomy (LCWHTO) and discusses areas where evidence remains inconclusive. Rather than proposing a single universal technique, this article emphasizes individualized decision-making based on patient anatomy, severity of OA, ligament status, patellofemoral joint condition, planned correction, and surgeon experience.