Fig. 2

Femoral and tibial component rotational angle. Axial computed tomography (CT) image of the femur. The surgical epicondylar axis (SEA) connects the lowest point of the medial epicondyle to the midpoint of the lateral epicondyle. The prosthetic posterior condylar line (PCL) connects the medial and lateral prosthetic posterior condylar surfaces. The femoral component rotational angle was defined as the angle between the SEA and the PCL. Axial CT image of the tibia. Akagi’s line connects the center of the posterior cruciate ligament and the medial border of the tibial tuberosity. The tibial component rotational angle was defined as the angle between the centerline of the tibial component and Akagi’s line. The difference in rotational angles between the femoral and tibial components constituted the rotational mismatch