A finite rotation, small strain 2D elastic head model, with applications in mild traumatic brain injury

TL;DR

This paper introduces a simple 2D elastic head model that accounts for finite rotations, enabling rapid prediction of brain strains during traumatic impacts, which could improve injury risk assessment and protective gear design.

Contribution

It presents a novel 2D elastic head model incorporating finite rotations, improving upon prior small rotation models for better brain injury prediction.

Findings

Model predicts strains comparable to detailed finite element models.

Enables rapid estimation of brain injury risk from rotational motions.

Serves as a foundation for more advanced head models.

Abstract

Rotational head motions have been shown to play a key role in traumatic brain injury. There is great interest in developing methods to rapidly predict brain tissue strains and strain rates resulting from rotational head motions to estimate brain injury risk and to guide the design of protective equipment. Idealized continuum mechanics based head models provide an attractive approach for rapidly estimating brain strains and strain rates. These models are capable of capturing the wave dynamics and transient response of the brain while being significantly easier and faster to apply compared to more sophisticated and detailed finite element head models. In this work, we present a new idealized continuum mechanics based head model that accounts for the head's finite rotation, which is an improvement upon prior models that have been based on a small rotation assumption. Despite the simplicity of the model, we show that the proposed 2D elastic finite rotation head model predicts comparable strains to a more detailed finite element head model, demonstrating the potential usefulness of the model in rapidly estimating brain injury risk. This newly proposed model can serve as a basis for introducing finite rotations into more sophisticated head models in the future.