ABAQUS Scripting for Bone Microstructure Modeling and Cutting Analysis in Cortical Bones

Vibration-assisted cutting (VAC) has transitioned from industrial applications to orthopedic bone cutting. However, the anisotropic nature of bone complicates the process due to its intrinsic toughening mechanisms and susceptibility to surface damage. Finite element analysis (FEA) is widely used to evaluate cutting efficiency, but simulating toolbone contact remains challenging due to large deformations causing convergence issues. To simplify modeling, this study develops a Python-based micro-modeling framework incorporating user-defined bone microstructure and porosity. Two models, representing young and aged bones, are validated by comparing stress intensity factors with analytical results for a single-edge notch bending (SENB) specimen, yielding a 4.5% deviation. Using the extended finite element method (XFEM), these models are used to examine the effects of amplitude and cutting depth on VAC performance. Results indicate that VAC reduces cutting force by up to 30.6% in aged bone compared to conventional cutting, with force reductions being more pronounced at higher amplitudes. Cutting stress is also reduced, particularly at 40 μm depth, where VAC decreases von Mises stress by 4