Citation

Dupuis R, Meyer F, Willinger R. Proc. Int. Tech. Conf. Enhanced Safety Vehicles 2005; 2005: 9p.

Copyright

(Copyright © 2005, In public domain, Publisher National Highway Traffic Safety Administration)

DOI

unavailable

PMID

unavailable

Abstract

Despite recent progress in occupant safety, the protection of children is still not optimal. To offer a better understanding of child injury mechanisms, the present study proposes a human-like finite element model of a three year old child’s neck. The subject was scanned with a medical scanner. The images were first semi-automatically segmented in order to extract the soft tissues and the bones. In the second step, the authors separate the different bones slice by slice on the geometry previously reconstructed. The anatomic structures are identified and each vertebra is reconstructed independently with special attention for the articular process. In a second step, the authors have generated a original meshing on the previous geometry to obtain a finite element model of the child’s neck. The anatomical structures incorporated are the head, the seven cervical vertebrae (C1–C7), the first thoracic vertebra (T1), the intervertebral discs and the principle ligaments which are modelled using non-linear shock-absorbing spring elements. The stiffness values used are taken from literature, and scaled down using scale factors from Irwin. This model incorporates 7340 shell elements to model the eight vertebrae, the head and 1068 solid 8-node elements to model the intervertebral discs. Contact between the articular surfaces is represented by interfaces permitting frictionless movement. Since this study does not aim to reproduce bone fractures, the authors have modelled the cervical vertebrae as rigid bodies. A scaling factor for the intervertebral discs modulus of 0,705 is supposed by Yoganandan for the 3 year old child. Given that validation data were not available, the model validation was conducted against Q3 dummy component sled tests. The accelerometric responses of the head model were similar with those recorded experimentally with a Q3 dummy neck in rearward, frontal and lateral impact direction.