Computed Tomography-based Surgical Navigation for

Component malpositioning and postoperative leg length dis-crepancy are the most common technical problems associ-ated with total hip arthroplasty (THA). Surgical navigation offers the potential to reduce the incidence of these problems. We reviewed 317 patients (344 hips) that underwent THA using computed tomography-based surgical navigation, in-cluding 112 THAs using a simplified method of measuring leg length. Guided by the navigation system, cups were placed in 40.8 ° ± 2 ° of operative abduction (range, 35°–50°) and 30.8 ° ± 3.2 ° (range, 19°–43°) of operative anteversion. We subsequently measured radiographic abduction on plain anteroposterior pelvic radiographs and calculated abduction and anteversion. Radiographically, 97.1 % of the cups were in the safe zone for abduction and 92.4 % for anteversion. The mean incision length was less than 8 cm for 327 of th