Medial open-wedge proximal tibial osteotomy is among the surgical treatments revealed successful clinical outcomes in patients with early-stage medial compartmental gonarthrosis. Plate fixator system (Tomofix) is commonly used for the fixation of medial open-wedge proximal tibial osteotomy. Plate fixator system (Tomofix) has been designed as a locking compression plate-screw system in order to provide increased biomechanical stability at the site of osteotomy. When plate fixator (Tomofix) used, union at the osteotomy site as well as protecting the acquired correction can be achieved with high success rates. Besides, in low-degree corrections, it reduces necessity of grafting the osteotomy line. On the other hand, dimensions and thickness of the plate fixator may cause need for implant removal due to irritation.