Abstract
BACKGROUND: Transtrochanteric rotational osteotomy (TRO) for osteonecrosis of the femoral head (ONFH) is considered technically demanding, with varying results among institutions. This is due to the complex soft tissue exposure and determination of the osteotomy line. We report a case in which the osteotomy line was assessed using the Stryker OrthoMap(®) three-dimensional (3D) computed tomography (CT)-based navigation system and determined as preoperatively planned. CASE PRESENTATION: The patient was a 24-year-old male with alcohol-related ONFH. Japanese Investigation Committee Classification Type C2/C2 Stage 3b/3b was confirmed through magnetic resonance imaging, and TRO was performed bilaterally on the same day using the Stryker OrthoMap(®) 3D CT-based navigation system. The patient was hospitalized for 55 days, and full loading was allowed at 6 months postoperatively. Eight months after surgery, the patient could return to work at his previous job in the restaurant industry relatively quickly. One and a half years postoperatively, the functional score improved from a preoperative visual analog scale of 90 to 12 mm at and the Japanese Hip Society Hip Evaluation Questionnaire improved from 31 points preoperatively to 59 points. CONCLUSIONS: This is the first report of a bilateral TRO for bilateral ONFH performed on the same day using CT-based navigation. For osteonecrosis, which is often bilateral, accurate determination of the osteotomy line as planned preoperatively using CT-based navigation contributes to shorter operative time, less intraoperative blood loss, and allows for bilateral same-day surgery. This may improve situations in which patients are hesitant to undergo bone-preserving surgery because of the long period of time required to return to work, thereby facilitating their early reintegration into society.