Fig. 3
From: Assessing component orientation of total hip arthroplasty using the low-dose bi-planar radiographs
A-D The pelvis and femur are 3D reconstructed. A Identification of the acetabular axis by the edge of the cup. B Identification of the sacral crest. C Identification of the bilateral anterior superior iliac spine (ASIS) and pubic tubercles, and the midline of bilateral ASIS. D Definition of the stem anteversion as the angle formed by the axis of the femoral neck and the posterior tangential line of femoral condyles