The Effect of Material Inhomogeneous for Femoral Finite Element Analysis
The accuracy of a finite element simulation depends mostly on the mesh model. Many parameters influence the precision of a finite element mesh. In orthopedic biomechanics, the material property of bone is one of the major parameters in the simulation, especially the heterogeneous of cortex and cancellous bone. The common approach to simulate the heterogeneous of bone is to model with several sets of elastic modulus for the bone material. However, the required set numbers of elastic modulus to obtain a feasible solution is still unclear for bone structure. The objective of this study was therefore to investigate the necessary of heterogeneous femoral material for finite element simulation. Three rabbit femora were selected as the target subjects and three-point bending test was used as the loading mode. Experimental measurement of the displacement value under the three-point bending test was used as the reference point for justification the analytical results and convergence. The results indicated that the displacement value decreased as the set number of cortex elastic modulus reduced. To achieve a 5% absolute convergence for displacement, a minimum of 60 sets of cortex bone elastic modulus is required.