Measurement methods: The baseline (yellow line) was obtained by connecting the center of the bilateral Y-shaped cartilage, and the vertical baseline was used as the reference line (red dotted line). The anterior and posterior margins of the bone acetabulum were connected (red solid line), and the angle of intersection with the reference line was the AAA. A parallel line (blue line) was made through the straight bone cortex of the inner wall of the pelvis, and the angle of intersection with the reference line was the IWAA. The distance from the highest point of the anterior and posterior margins of the bony acetabulum to the straight line of the pelvic wall was the A (green line) and P (green line), respectively. The distance from the point of the projection of the highest point of the anterior and posterior walls onto the straight line of the pelvic wall was the W (brown line).