Acetabular frontal inclination and femoral stem position. Pelvic anteroposterior radiograph. The acetabular inclination corresponds to the orange angle between the acetabular piece contour (orange circle) and the transichiatic line (dotted yellow line). Additionally, note that the acetabular piece is aligned (green line) with the bottom of teardrop shadow (dotted black curve). The femoral stem should be placed in a neutral position (blue line). A slight valgus (red line) can be tolerated, but varus (yellow line) should not occur.