title: Dynamic Response and Residual Helmet Liner Crush Using Cadaver Heads and Standard Headforms.
abstract: Biomechanical headforms are used for helmet certification testing and reconstructing helmeted head impacts; however, their biofidelity and direct applicability to human head and helmet responses remain unclear. Dynamic responses of cadaver heads and three headforms and residual foam liner deformations were compared during motorcycle helmet impacts. Instrumented, helmeted heads/headforms were dropped onto the forehead region against an instrumented flat anvil at 75, 150, and 195 J. Helmets were CT scanned to quantify maximum liner crush depth and crush volume. General linear models were used to quantify the effect of head type and impact energy on linear acceleration, head injury criterion (HIC), force, maximum liner crush depth, and liner crush volume and regression models were used to quantify the relationship between acceleration and both maximum crush depth and crush volume. The cadaver heads generated larger peak accelerations than all three headforms, larger HICs than the International Organization for Standardization (ISO), larger forces than the Hybrid III and ISO, larger maximum crush depth than the ISO, and larger crush volumes than the DOT. These significant differences between the cadaver heads and headforms need to be accounted for when attempting to estimate an impact exposure using a helmet's residual crush depth or volume.
authors.affiliation: Department of Industrial Engineering, University of Miami, Miami, FL, USA.|MEA Forensic Engineers & Scientists, Laguna Hills, CA, USA.
authors.forename: S J
authors.initials: SJ
authors.lastname: Bonin
authors.affiliation: Injury Biomechanics Laboratory, Duke University, Durham, NC, USA.
authors.forename: J F
authors.initials: JF
authors.lastname: Luck
authors.affiliation: Injury Biomechanics Laboratory, Duke University, Durham, NC, USA.
authors.forename: C R
authors.initials: CR
authors.lastname: Bass
authors.affiliation: MEA Forensic Engineers & Scientists, Laguna Hills, CA, USA.
authors.forename: J C
authors.initials: JC
authors.lastname: Gardiner
authors.affiliation: St. Jude Children's Research Hospital, Memphis, TN, USA.
authors.forename: A
authors.initials: A
authors.lastname: Onar-Thomas
authors.affiliation: Department of Industrial Engineering, University of Miami, Miami, FL, USA.
authors.forename: S S
authors.initials: SS
authors.lastname: Asfour
authors.affiliation: MEA Forensic Engineers & Scientists, 11-11151 Horseshoe Way, Richmond, BC, V7A 4S5, Canada. gunter.siegmund@meaforensic.com.|School of Kinesiology, University of British Columbia, Vancouver, BC, Canada. gunter.siegmund@meaforensic.com.
authors.forename: G P
authors.initials: GP
authors.lastname: Siegmund
mesh_terms: D002102:Cadaver; D006259:Craniocerebral Trauma / Q000473:pathology / Q000517:prevention & control*; D006257:Head; D006260:Head Protective Devices; D006801:Humans; D008297:Male; D008954:Models, Biological
keywords: Cadaver head; Head Impact; Headform; Helmet; Residual crush