An open source software tool to assign the material properties of bone for ABAQUS finite element simulations

A new software tool to assign the material properties of bone to an ABAQUS finite element mesh was created and compared with Bonemat, a similar tool originally designed to work with Ansys finite element models. Our software tool (py_bonemat_abaqus) was written in Python, which is the chosen scripting language for ABAQUS. The purpose of this study was to compare the software packages in terms of the material assignment calculation and processing speed. Three element types were compared (linear hexahedral (C3D8), linear tetrahedral (C3D4) and quadratic tetrahedral elements (C3D10)), both individually and as part of a mesh.

Comparisons were made using a CT scan of a hemi-pelvis as a test case. A small difference, of -0.05 kPa on average, was found between Bonemat version 3.1 (the current version) and our python package. Errors were found in the previous release of Bonemat (version 3.0 downloaded from www.biomedtown.org) during calculation of the quadratic tetrahedron Jacobian, and conversion of the apparent density to modulus when integrating over the Young’s modulus field. These issues caused up to 2 GPa error in the modulus assignment. For these reasons, we recommend users upgrade to the most recent release of Bonemat.

Processing speeds were assessed for the three different element types. Our Python package took significantly longer (110 s on average) to perform the calculations compared with the Bonemat software (10 s). Nevertheless, the workflow advantages of the package and added functionality makes ‘py_bonemat_abaqus’ a useful tool for ABAQUS users.