Figure 2

Landmarks of the rat skeleton used for the determination of the knee joint angle. Point 1 is the center of the proximal femur epiphysis at the level of the femur neck, point 2 is the center of the distal femur epiphysis at the level of the epicondylus (with points 1 and 2 defining the femoral axis), point 3 is the center of the proximal tibial epiphysis and point 4 is the center of the distal tibial epiphysis at the level of the ankle (with points 3 and 4 defining the tibial axis). The knee joint angle was calculated on the posterior side between the two axes (Angle).