Tibial rotational alignment was significantly improved by use of a CT-navigated control device in total knee arthroplasty.

This study compared the accuracy of three methods to set tibial component rotational alignment: (1) conventional method, the anteroposterior (AP) axis was determined by the surgeon using anatomical landmarks; (2) partial-navigation method, the tibia was prepared according to the AP axis using a CT-based navigation system and the component was manually positioned; (3) full-navigation method, the tibial component was positioned and fixed with cement under the control of navigation using a newly developed instrument. The conventional method showed considerable deviation (range, -18.6° to 14.7°), and the partial-navigation method also showed considerable deviation (-11.3° to 8.1°). In contrast, the full-navigation method significantly improved the accuracy of alignment (-2.9° to 2.1°). The tibial component can become malaligned during cement fixation, even after proper bone preparation.