The structural adaptation of a three-dimensional finite element model of the proximal femur is considered. Presuming the bone possesses the optimal structure under the given loads, the bone material distribution is found by minimizing the strian energy averaged over ten load cases with a volume constraint. The optimized design is used as a start-configuration for the remodeling simulation. The parameter characterizing the equilibrium level where no remodeling occurs is estimated from the optimization parameters. The loads vary in magnitude, location and direction simulating time dependent loading. The remodeling algorithm is derived directly from the optimization recurrence formula, and in a time increment the material distribution changes towards the optimal structure for the present load case. The speed of remodeling is taken from clinical data. Numerical examples of respectively increasing and reducing the joint forces are given.
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