Fig. 4A–D.

The radiographs of a 24-year-old woman from Group I (optimal acetabular retroversion and spherical femoral head) are shown. (A) The preoperative AP radiograph showed deficient lateral coverage. (B) Femoral head-neck offset was decreased in the preoperative crosstable view. At the 10-year followup the patient presented with a Merle d’Aubigné-Postel score of 17 points. (C) The AP radiograph showed sufficient lateral coverage and corrected version of the acetabulum without signs of progression of OA. (D) The decreased head-neck offset was corrected by performing an osteochondroplasty of the femoral head-neck junction, leading to impingement-free ROM.