Varus-valgus balancing in knee replacement surgery

There are many different approaches to achieving balancing in total knee surgery. The most frequently used method is to obtain correctly aligned bone cuts, and then carry out necessary soft tissue releases to achieve equal flexion and extension gaps. In some techniques, the bone cuts themselves are determined by the prevailing soft tissue status or the kinematics during flexion-extension. Navigation can provide quantitative data during these processes but so far, navigation is used in only in a minority of cases. However in recent years, new technologies have been introduced with lower cost and implementation time, allowing for more widespread use. Early studies have indicated that more reproducible balancing can be obtained, and that balancing has a positive effect on clinical outcomes. However the ability to measure balancing quantitatively during surgery, has raised the questions of the most systematic method for implementation during surgery, and the relative influence of various correcting factors. F...