Three-dimensional curved beam stress analysis of the human femur

Abstract

We discuss an analytical approach to the investigation of the normal, shear, and principal stresses transmitted to the human femur. Two cases are considered: in the first the femur is treated as a three dimensional isotropic curved beam, and in the second as a three dimensional anisotropic composite curved beam, consisting of two different materials, the spongy bone and the cortical bone. The composite beam theory is used to investigate stresses in the femur, in which the spongy bone is surrounded by a cortical bone jacket; compatibility of stresses and strains being introduced at the interface of the two bones in order to derive the stress equations at any point in the cross section. General loading conditions are considered in the analysis, in which the femur is subjected to normal and shear forces, and to biaxial bending and twisting moments.