Fig. 5From: Focal concavity of posterior superior acetabulum and its relation with acetabular dysplasia and retroversion in adults without advanced hip osteoarthritisRelation between acetabular dysplasia and retroversion in subjects at 50 years or younger with focal concavity of posterior superior acetabulum. Focal concavity of posterior superior acetabulum was evaluated by three-dimensional CT image. Acetabular dysplasia was determined by lateral center edge angle <25°, Tönnis angle >10°, or anterior center edge angle <25° on standing pelvic radiographs. Acetabular retroversion was judged by version angle <0° at the one-fourth cranial level of axial CT imageBack to article page