Fig. 2

Reference points for 3D-CT measurement of anteversion. A proximal reference point in the center of the medullary canal at the lower level of trochanter minor and a second 3 cm more distal reference point in the center of the medullary canal formed the longitudinal axis of the femur. The perpendicular line (femoral offset) runs from the longitudinal axis of the femur to the center of rotation. The hip anteversion is the angle between this perpendicular line in relation to the posterior femoral condylar line