Finite element modelling of impact-induced axonal injury in sheep

Abstract

This paper describes a numerical study of axonal injury caused by an impact to the head of the anaesthetised sheep. In the model, described in Anderson et al. (2003), injury is closely related to the peak impact force and to kinematic measurements, particularly the peak change in linear and angular velocity. A three-dimensional finite element model of the sheep skull and brain was constructed to simulate the dynamics of the brain and skull during the impact. Model validation was attempted by comparing pressure measurements in the experiment with those calculated by the model. The distribution of axonal injury was then compared with the output of the finite element model. The finite element model could account for approximately thirty per cent of the variation in the distribution and extent of axonal injury.