Kim JT, et al. - Researchers located the site of the impingement and determined the width of tolerable osteophytes, which does not induce impingement during activities of daily living (ADL), using a three-dimensional simulation. They positioned the acetabular cups at 45° abduction and 20° anteversion, and the anteversion of femoral stems was 15°. In order to avoid impingement of the femur–stem construct on the acetabular osteophytes during ADLs, osteophytes excision of the anterosuperior and posterior portion of the acetabulum during a THA was suggested.