Reliability of 3D planning and simulations of medial open wedge high tibial osteotomies.

In medial open-wedge high tibial osteotomy (HTO) hinge axis and osteotomy plane influence the resulting anatomy, but accurate angular quantifications using 3D-planning-simulations are lacking. The objectives of this study were developing a standardized and validated 3D-planning method of an HTO and to perform several simulated realignments to explain unintended anatomy changes. The cutting direction of the main osteotomy was defined parallel to the medial tibial slope and the hinge axis 1.