Table 2 The comparison of the femoral head center location between the DDH (Crowe I-III) group and the healthy control group with all the data mapped proportionally to a representative normal pelvis (the pelvic width = 272.1 mm, the pelvic height = 194.5 mm and the pelvic depth = 136.1 mm). The comparison of the 3D displacement of the femoral heads in DDH patients of different Crowe types relative to the healthy control group. The femoral head center location of the DDH group is significantly more anterior, superior, and lateral than those of the healthy control group. The Crowe classification corresponded to the degree of the femoral head displacement in the SI and 3D distance, while not reflecting the degree of displacement in the ML and SI directions

From: Relations between the Crowe classification and the 3D femoral head displacement in patients with developmental dysplasia of the hip