Fig. 3

Measurements of TT-TG, DFT, PFCT and PTT. a, Slice above the gastrocnemius insertion of the distal femur. b, Slice of the gastrocnemius insertion of the distal femur. c, Slice of the proximal tibia. d, Slice of the level of the tibial tuberosity. A The TT-TG distance is the superposition of slices b and d. The TT-TG distance is defined as the distance measured on MRI between the most anterior part of the tibial trochanter and the middle of the trochlear groove. B The DFT is the superposition of slices a and b. The DFT is defined as the angle between the posterior cortical line of the distal femur and the posterior condylar line. C PFCT is defined as the angle between the line passing through the medial sulcus/apex of lateral epicondyle and the line passing through the posterior condylar axis on the slice b. D The PTT is the superposition of slices c and d. The PTT is defined as the angle between the line that joins the posterior border of the tibial plateaus at the level of the tibial insertion of the posterior cruciate ligament and the line that joins the posterior border of the tibia at the level of the tibial tubercle. TT-TG, tibial tubercle to trochlear groove. DFT, distal femoral torsion. PFCT, posterior femoral condylar torsion. PTT, proximal tibial torsion