<qa>  What is the thickness of the radiolucency in the acetabular or fe2. Conventional X-rays: To evaluate possible aseptic loosening, all patients will have a standardized full pelvic antero-posterior X-ray and a lateral X-ray with fixed magnification both preoperatively, postoperatively, at the 2 years follow-up visit and at the 5 years follow-up visit. Radiolucent lines at the bone-implant interface and evidence of osteolysis will be measured on both recordings. The standard Gruen zones will be used to record radiolucency surrounding the femoral component and the acetabular zones described by DeLee and Charnley will be used to record radiolucency surrounding the acetabular component. The apparent thickness of the radiolucency within these zones will be recorded. Evidence of osteolysis radiolucency 2mm thickness in the periprosthetic tissue of the acetabular or femoral component will be considered a failure. 