Fig. 1

a: Pre-operative anteroposterior (AP) radiographs taken in June 2011. The patient had undergone bilateral total hip arthroplasty more than 10 years prior. The X-rays revealed wear of the acetabular linings of both hips, and severe osteolysis of both proximal femora and acetabula. b: Radiograph taken after revision of the right hip in 2011. c: Pre-operative AP radiograph taken in 2013. d: Radiograph taken after revision of the left hip in 2013