Objective: To simulate the mechanical and fracture behaviors of cancellous bone in three anatomical directions and to develop an equivalent constitutive model. Method: Micro-scale XFEM models of a cancellous specimen were developed with mechanical behaviors in three anatomical directions. An appropriate ABAQUS macro-scale model replicated the behavior observed in the micro-scale models. The parameters were defined based on the intermediate bone material properties in the anatomical directions and assigned to an equivalent non-porous specimen of the same size. The equivalent model capability was analyzed by comparing the micro- and macro- models. Results: The hysteresis graphs of the micro-scale model show that the modulus is the same in loading and unloading; similar to the metal plasticity models. The strength and failure strains in each anatomical direction are higher in compression than in tension. The micro-scale models exhibited an orthotropic behavior. Appropriate parameters of cast iron plasticity model were chosen to generate macro-scale models that are capable of replicating the observed micro-scale behavior of cancellous bone. Conclusion: Cancellous bone is an orthotropic material that can be simulated using a cast iron plasticity model. This model is capable of replicating the micro-scale behavior in FE analysis simulations without the need for individual trabecula, leading to a reduction in computational resources without sacrificing model accuracy. Also, XFEM of cancellous bone compared to traditional FEM proves to be a valuable tool to predict and model the fractures in the bone specimen.

This content is only available via PDF.
You do not currently have access to this content.