–REPORT OF TWO CASES–

Various complications occur during total hip arthroplasty (THA). It is common to implement trial treatments of various implants during THA. Here we report on 2 cases in which the trial femoral head fell into the pelvis and migrated during THA. The trial head was not retrieved but left inside in one case, while the other presented the opportunity for a possible retrieval. It is important to recognize the existence of such rare complications. Key Words: total hip arthroplasty, intraoperative Migration, intraoperative complicatio