Finite Element Analysis of Femur Stress under Bending Moment and Compression Load

A quantitative assessment of femur stress under compression and bending condition is essential for the understanding of failure mechanisms and providing guidance for the design and operation of femur replacement. The stress distribution of femur under bending moment and compressive load is simulated using finite element method (FEM) in this paper. A two-dimensional FEM model is established according to the dimension of a typical human femur. The bending moments are obtained by shifting the load action point to the outward lateral direction. Four excursion lengths 0mm, 5mm, 10mm and 15mm are tested. The deformation and stress distribution of femur, the stress in the cross section of femoral head, neck and femoral shift under bending moment and compressive load are obtained. It can be found from the numerical results that there is obvious stress concentration at femoral neck and tension stress occurs in the outside while the compressive stress occurs in inner side. In the cross section of femoral shaft, tension stress again occurs in the outside and compressive stress occurs in inner side. The femur stress increases significantly with the bending moment.