Explicit Finite Element Method Applied to Impact Biomechanics Problems

Biofidelic numerical models require accurate geometry, material properties, representative loading conditions, and proper verification and validation based on relevant experimental studies. Imaging techniques such as CT or MRI are typically used to generate anatomically correct model geometry. Accurate biological material properties and constitutive models present a challenge since tissues are typically anisotropic with nonlinear viscoelastic behavior and must be represented using a continuum approach. Verification and validation is a crucial development step to demonstrate the biofidelity of the model against experimental studies and is differentiated from model calibration, which involves adjusting FE modeling parameters to improve the agreement between the model and experimental data. Validation of the model should be performed in a continuous stepwise process, with increasing levels of complexity. Evaluating a numerical model against a variety of different loading conditions is the best means to obtain a fully validated model and this should be considered as a continuous process throughout the useful life of the model.