Reverse Periacetabular Osteotomy

True retroversion of the acetabulum, defined as positive cross-over sign, positive posterior wall sign, and positive ischiatic spine sign, is one possible etiology of femoroacetabular impingement. Several treatments have been proposed, going from rim trimming to reorientation of the acetabulum. The choice of treatment is critical for long-term survival of the joint. Radiological diagnosis of retroversion, indications, and surgical technique of reverse periacetabular osteotomy and simultaneous femoral offset correction are presented.