Fig. 4

Rototional malalignment of the TKA. a) shows 3.3⁰ of internal rotation of the femoral component of patient 3, measured as the angle between the posterior condylar axis and the surgical transepicondylar axis. b-d) show 4.4⁰ tibial component rotation, measured in accordance with the Berger protocol, wherefore b shows the top of the tibia tuberosity, which is connected with the centre of the tibia determined in c. In d, the angle between the yellow line and the green line perpendicular on the tangent of the tibia plateau of the tibial component (red) was calculated as 4.4⁰ tibial component rotation