The axisymmetric computational study of a femoral component to analysis the effect of titanium alloy and diameter variation.

This work presents a numerical approach in order to predict the influence of implant material stiffness in a femoral component design when submitted in compression. The implant success depends on the transferred load to the neighboring bone. The finite element method can be used to analysis the stress and strain distribution in the femoral component allowing to improve the implant selection. For this purpose, 2D axisymmetric computational models of an implant-cement-bone (Model 1), implant-bone (Model 2) and core implant-bone (Model 3) were constructed using the finite element method with ANSYS program. The finite element model was assumed a state of ideal osseointegration, where the cortical bone, cement and implant were assumed as perfectly bonded. Three different implant diameters were chosen and two materials considered, a typical titanium alloy and iso-elastic titanium alloy with low stiffness. The finite element analysis was carried out to calculate the von Mises stress, the shear stress and the strain energy density in all studied models. Also, an analytical procedure, based on the elastic stress theory and applied to composite materials for an axial load, was used to measure the load transferred to the bone. In all results, Model 3 with the vertical graded iso-elastic alloy in vicinity to the bone with high diameter has a good performance.