Fig. 1

Measurements of radiographic parameters in anteroposterior and 65° false⁃profile pelvic X-ray radiographs in the standing position. a Lateral center-edge angle (LCEA) is the intersection angle between the vertical center line of the femur and the lateral edge of the acetabulum; AI is the intersection angle formed with the connection line between the acetabular endocoxa and acetabular outer margin and the pelvic horizontal line. b Anterior central edge angle (ACEA) measurement on 65° obliquity on the pelvis of X-ray image. ACEA is the intersection angle formed with the vertical center line of the bilateral femoral head and the anterior margin of the acetabulum. c Discontinuity of Shenton line at the pelvis AP position on the X-ray image is defined as a more than 5 mm distance away from the connection line of the obturator superior border vertex and the head and neck junction of the femoral neck