Dynamic verification of a multi-body computational model of human head and neck for frontal, lateral, and rear impacts

Abstract

A multi-body computational model of the human head and neck was previously shown to be in good agreement with experimental findings from actual human cervical spine specimens. The model segments were tested in three directions of loading showing main and coupled motions to be accurate and realistic. The model's ability to predict the dynamic response of the head and neck, when subjected to acceleration pulses representing frontal, lateral, and rear-end impacts, is verified using experimental data derived from sled acceleration tests with human volunteers for 15 g frontal and 7 g lateral impacts and from isolated cervical spine specimen tests for rear-end impacts. Response corridors based on sled acceleration tests with human volunteers for frontal and lateral impacts are used to evaluate the model and investigate the effect of muscle activation on the head-neck motion. Firstly, the impacts are simulated with both passive and active muscle behaviour. Secondly, the local loads in the soft-tissue elements during the frontal impact are analysed. For rear-end impact simulation experiments using ligamentous isolated cervical spine specimens are used to evaluate the model performance before investigating the effects of muscle tensioning. Good agreement with human volunteer response corridors resulting from frontal and lateral impacts, and isolated cervical spine specimen sled test rear-end impact experiments is demonstrated for the model, highlighting the important role the muscles of the neck play in the head-neck response to acceleration impacts. The model is shown to be able to predict the loads and deformations of the cervical spine components making it suitable for injury analysis.