COMPUTATIONAL MODEL TO PREDICT CHANGES IN IN VIVO KINETIC EFFECTS DUE TO COMPONENT MALALIGNMENT IN TOTAL KNEE ARTHROPLASTY

Abstract

The objective of this study was to compute the in vivo dynamic tibiofemoral contact forces for normal alignment, and then evaluate the change in contact forces and pressures with increasing varus-valgus and internal-external rotational malalignment of the femoral component. A three-dimensional computational model of the lower limb during deep knee bend was created using Kane’s method of dynamics. The change in forces from normal with malalignment of up to 10° valgus, 10° varus, 10° internal axial femoral rotation, and 10° internal axial femoral rotation were determined. In this study, varus-valgus malalignment had the greatest effect on medial-lateral pattelofemoral contact forces, with a maximum increase of 2.25 times body weight for 10° valgus malalignment. Axial malalignment had the greatest influence on tibiofemoral contact forces.