Table of Contents
ISRN Orthopedics
Volume 2013, Article ID 328246, 6 pages
http://dx.doi.org/10.1155/2013/328246
Research Article

Femoral Neck Version Affects Medial Femorotibial Loading

1Department of Orthopaedics, General Hospital of Xanthi, 67100 Xanthi, Greece
2BioHexagon Ltd., Varnis 36, 17124 Athens, Greece

Received 27 December 2012; Accepted 22 January 2013

Academic Editors: C.-H. Lee, E. L. Steinberg, M. van der Linden, B. K. Weiner, and S. Yabuki

Copyright © 2013 T. A. Papaioannou et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

The aim of this study was to provide a preliminary evaluation of the possible effect that femoral version may have on the bearing equilibrium conditions developed on the medial tibiofemoral compartment. A digital 3D solid model of the left physiological adult femur was used to create morphological variations of different neck-shaft angles (varus 115, normal 125, and valgus 135 degrees) and version angles (−10, 0, and +10 degrees). By means of finite element modeling and analysis techniques (FEM-FEA), a virtual experiment was executed with the femoral models aligned in a neutral upright position, distally supported on a fully congruent tibial tray and proximally loaded with a vertical only hip joint load of 2800 N. Equivalent stresses and their distribution on the medial compartment were computed and comparatively evaluated. Within our context, the neck-shaft angle proved to be of rather indifferent influence. Reduction of femoral version, however, appeared as the most influencing parameter regarding the tendency of the medial compartment to establish its bearing equilibrium towards posteromedial directions, as a consequence of the corresponding anteroposterior changes of the hip centre over the horizontal tibiofemoral plane. We found a correlation between femoral anteversion and medial tibiofemoral compartment contact pressure. Our findings will be further elucidated by more sophisticated FEM-FEA and by clinical studies that are currently planned.