Computational method for determination of bone and joint loads using bone density distributions

Because bone structure is influenced by mechanical loading during ontogeny, the geometry and density distribution of bones contain information about their loading histories. Based on a mathematical theory relating stress history to bone remodeling, we have developed a method to determine dominant bone loading conditions using an optimization procedure. We applied this load determination method using a simplified two-dimensional bone-end finite element model, for which a standard density distribution had been calculated under a given set of loading conditions. With this density distribution, the optimization procedure was used to determine the original loads from a broad set of many plausible basic load distributions and locations. The optimization procedure adjusted the magnitude of each basic load to achieve the desired tissue level attractor stress stimulus throughout the model. The results show that the density-based bone load determination method yields accurate results for basic test cases and, thus, may have potential for estimating in vivo bone loads for both extant and extinct animals.