Improvement of activities of daily living after total hip arthroplasty using a computed tomography-based navigation system.

The purpose of this study was to evaluate the outcome improvements after total hip arthroplasty (THA) using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) in patients who underwent THA with a navigation system in our institutions. The subjects were 219 patients. All patients had adequate data to allow complete scoring of the WOMAC for a 1-year postoperative follow-up. CT-based navigation was used in all THAs. Postoperatively, no restrictions were imposed on patients' ADL. One year after surgery, the average WOMAC pain subscale score was 1.8 ± 2.9, the stiffness subscale score was 1.1 ± 1.6, and the physical function subscale score was 7.5 ± 11.6 points. The number of patients whose score for the WOMAC physical function score was 0 points was 61 (27.9%). A lower WOMAC score usually represents a better status. In some of the most difficult functions, such as ascending stairs, bending to the floor, putting on socks/stockings, and heavy domestic duties, the scores tended to be higher than the other scores postoperatively. These results show that THA using navigation can improve patients' postoperative QOL.