Optimizing alignment

Abstract

Optimizing alignment in total knee arthroplasty requires an understanding of the assumptions of a chosen instrumentation system. This understanding involves knowing the possible alignment errors of a system and knowing how the particular system leads the surgeon through the various steps of component placement. Current intramedullary and extramedullary instrumentation can assist in component placement; however, the surgeon must be aware of situations such as extra-articular deformities that can affect the final alignment. Additionally, computer-assisted knee navigation is available for routine use. These systems allow for more accurate positioning of jigs, the ability to correctly establish femoral component rotation, instantaneous feedback on overall alignment, and the ability to prevent implantation of malpositioned components. Overall, computer assistance results in decreased variability and the elimination of outliers. An armamentarium of alternative techniques must be kept in mind for use as secondary checks on the primary technique and in situations of distorted or absent anatomical landmarks. © 2005 Springer Medizin Verlag Heidelberg.