Radiological outcome analyses of transtrochanteric posterior rotational osteotomy for osteonecrosis of the femoral head at a mean follow-up of 11Â years

The results of this study indicate that the postoperative intact ratio is one of the main influences on progression of collapse and/or joint space narrowing after PRO, and should be at least 36.8 %. An increased awareness of this critical ratio would be useful for planning the optimal use of this procedure.