Fig. 9

The treatment algorithm for protrusio joint preservation surgery is shown. We used MRA with radial sequences to determine the status of the articular cartilage. In cases without cartilage degeneration, open surgical dislocation with osteochondroplasty of the acetabular rim and femoral neck is recommended. Valgus ITO may be indicated in cases with inadequate femoroacetabular clearance. In cases with early cartilage degeneration on MRA, the osteochondroplasty is not sufficient and osteotomy of the pelvis, femur, or both depends on the individual morphology. MRA, magnetic resonance arthrography; ITO, intertrochanteric osteotomy; FA, femoroacetabular; WB, weight bearing.