System as a measurement tool Variation in femoral rotational alignment lines in total knee replacement

摘要

Objectives: The purpose of this study was to measure the variation of three different lines for femoral rotational alignment to show the possible difference and check the so far used values in manual instrumentation technique. Background: Flexion Stability and Patella tracking after Total Knee Replacement is mainly influenced from the rotational alignment of the femoral component [1, 4]. Different implant philosophies use different landmarks for rotational alignment, as the epicondylar line, the posterior condyles or the antero-posterior line (APL/"Whiteside-line"). In manual technique, depending on the implant, only a small variation of rotational positioning is possible by the given instruments. A given value of the difference between the transcondylar line (TCL) and the dorsal condylar line (DCL) is 3掳 of internal rotation of the DCL related to the TCL [2]. An individual variation is known; detailed measurements of this variation are available only for small collectives with special pathology [4].