Measurement of the trochlear groove medialization. The total width of the distal femoral condyle, which is parallel to the femoral posterior condylar line (fPCL), denoted by a solid line, is defined as G. The distance between the medial border of the distal femoral condyle and the bottom of the trochlear groove, which is parallel to the fPCL, is defined as g. The trochlear groove medialization is calculated as g ÷ G.