Correlation between Femoral Head Lateralization and Bone Morphology in Primary Hip Osteoarthritis

Figure 2

θ1 is Sharp’s angle. θ2 is the CE angle. θ3 is the femoral shaft-neck angle (FNA). b/c is the acetabular depth ratio (ADR). Sharp’s angle was the angle between the line joining the lateral aspect of the weight-bearing zone and the inferior point of the teardrop, parallel to the transverse axis of the pelvis. The CE angle was the angle between the line joining the lateral aspect of the weight-bearing zone and the center of the femoral head with the line perpendicular to the transverse axis of the pelvis. FNA was the angle between the axis of the femoral neck and femoral shaft. ADR was calculated by dividing the depth of the acetabulum by the length between the inferior teardrop point and the lateral weight-bearing zone of the center of the femoral head in the coronal plane, then multiplying by 1000.