title: Estimating the influence of neckform compliance on brain tissue strain during a Helmeted impact.
abstract: The aim of this study was to determine if a change in neckform compliance could influence maximum principal strain in the brain white and grey matter, the brain stem and the cerebellum. This was done by impacting a Hybrid III headform with a 16.6 kg impactor arm at 5 m/s. Three different Hybrid III neckforms were used: 1) one 50th percentile male neckform - standard neckform; 2) one 50th percentile male neckform plus 30 per cent compliance - soft neckform; 3) one 50th percentile male neckform minus 30 per cent compliance - stiff neckform. The kinematic data obtained was then used to drive a finite element model developed by University College Dublin. The results showed that a decrease in neckform compliance had a significant effect on maximal principal strain in the cerebellum, where the stiff neck (0.050 ± 0.004) generated higher maximum principal strains than the standard neck (0.036 ± 0.003) and the soft neck (0.037 ± 0.001). There were no significant differences between the stiff (0.122 ± 0.013), standard (0.114 ± 0.020) and soft neck (0.119 ± 0.019) in the white matter; the stiff (0.168 ± 0.011), standard (0.176 ± 0.011) and soft neck (0.176 ± 0.007) in the grey matter; or the stiff (0.080 ± 0.003), standard (0.081 ± 0.006) and soft neck (0.085 ± 0.009) in the brain stem. The results were not linked to brain injury due to the absence of a commonly accepted threshold.
authors.affiliation: Neurotrauma Impact Science Laboratory, University of Ottawa, A106-200 Lees Av., Ottawa, Ontario, K1S 5S9, Canada. prous088@uottawa.ca
authors.forename: Philippe
authors.initials: P
authors.lastname: Rousseau
authors.forename: T Blaine
authors.initials: TB
authors.lastname: Hoshizaki
authors.forename: Michael D
authors.initials: MD
authors.lastname: Gilchrist
authors.forename: Andrew
authors.initials: A
authors.lastname: Post
mesh_terms: D000063:Accidents, Traffic / Q000517:prevention & control*; D001921:Brain / Q000502:physiology*; D001930:Brain Injuries / Q000150:complications / Q000503:physiopathology*; D003187:Compliance; D006260:Head Protective Devices / Q000592:standards*; D006801:Humans; D008297:Male; D008348:Manikins; D008954:Models, Biological; D013180:Sprains and Strains / Q000209:etiology / Q000503:physiopathology*