Biomechanical analysis of functionally graded biomaterial disc in terms of motion and stress distribution in lumbar spine

In recent decades, the development of new biomaterials for medical applications has been one of the challenging tasks for biomaterial scientists. Functionally graded biomaterials (FGBM) have been receiving an increasing attention due to their unique advantage, being able to satisfy the requirements of both mechanical and biocompatibility properties simultaneously. This paper evaluates the motion range and stress distribution of FGBM and non-FGBM artificial discs in response to different loading conditions i.e. compression, bending moment and torsion. In order to ensure the accuracy of analytical solution, the numerical solution was performed using finite element method and good agreement was found between the analytical and finite element results. In addition, the experimental data reported in the previous literature were used to predict the optimal model of artificial FGBM disc using the proposed analytical solution. The results of this study suggest that FGBM parameters can play an important role in achieving the goal of mechanical function optimization.