We originally used two or three large cancellous screws for a transtrochanteric rotational osteotomy for osteonecrosis. Since January 2002, a screw and plate system (K-MAX Adjustable Angle Hip Screw) has been used to obtain more rigid fixation at the site of osteotomies. We investigated the clinical and radiological results of a transtrochanteric anterior rotational osteotomy.