Multiple techniques exist for treatment of irreducible painful hips in CP, including proximal femoral resection-interposition arthroplasty, resection at the femoral neck with subtrochanteric valgus osteotomy, hip replacement or hip arthrodesis (fusing the femur to the socket in a static position). This wide variation in practices is consistent with clinical uncertainty regarding the optimal treatment method for this problem. The most frequently performed intervention for a painful irreducible hip in the setting of CP is a form of resection arthroplasty, either alone (proximal femoral resection-interposition arthroplasty) or in conjunction with valgus support osteotomy. Technique selection is based on the functional level of the patient, patient symptoms, and surgeon preference.{{257 Van Riet,A. 2009; 253 Wright,P.B. 2013}}