Mixed uniform boundary conditions improve homogenized FE models of bone-screws and inverse remodelling

Abstract

In the field of numerical bone biomechanics, either micro finite element model (FE) or homogenized FE models (hFE) are used. The latter requires a material law that translates the information on the micro level into effective material behavior on the macro level. Different trabecular bone material models can be used, including orthotropic and isotropic material derived from homogenization based on kinematic uniform boundary conditions (KUBC) as well as periodicity-compatible mixed uniform boundary conditions (PMUBC) [1]. There are a number of studies that have described both [2] for stiffness or bone strength predictions. This work focuses on the question which kind of boundary condition is better suited in case of screw-bone construct and inverse bone remodeling algorithms. The gold standard are FE models of the same construct or bone.