Background: An improper femoral and tibial component rotation is one of a major reason leading to a failed TKA. There is controversial on determination of rotational alignment particularly on a tibial component. An anatomical landmarks and a self-aligned technique have been proposed. It is the authors’ purpose to determine the difference between two techniques in setting the rotation of tibial component.
Material and Method: The authors conducted a prospective, comparative study of 30 consecutive primary total knee arthroplasty. There were 4 men and 26 women with mean age of 68.6 years. All procedures were performed by a single surgeon with a navigation system. The degree of rotation of the tibial trial component established by a just-medial to the tibial tuberosity and self-aligned technique was compared.
Results: A mean of the degree of the tibial component rotation with the self-aligned of the center-post technique was 3° more externally rotated than the just-medial to the tibial tuberosity technique. The self-aligned technique had standard deviations of 4.41°, of which was significantly less variable (p < 0.05) than 5.94° of the just-medial to the tibial tuberosity technique.
Conclusion: The authors conclude that establishment of the tibial component rotation by using the self-aligned of the centerpost technique will rotate the component more external compared with the just-medial to the tibial tuberosity technique.

Keywords: Tibial component, Rotational alignment, Self-aligned of the center-post technique, Total knee arthroplasty, Navigation system