[Experimentally established material data of human femurs and analysis of direction-dependent stress tolerance]

All the calculations given in the literature concerning the material data for human femora are based on the very simplistic assumption that the bone is isotropic, i.e. that it has the same mechanical behaviour in every direction. This assumptions has been employed by all authors because no detailed data on bone as a material, especially in connection with the human femur. The results of the present experiments show, however, that the femur exhibits variations in material data which are markedly direction dependent, so that support can no longer be given to the simplistic assumption of isotropic behaviour.