title: Effect of Head-Neck Position on Cervical Facet Stretch of Post Mortem Human Subjects during Low Speed Rear End Impacts.
abstract: The purpose of this study was to determine the effect of head-neck position on cervical facet stretch during low speed rear end impact. Twelve tests were conducted on four Post Mortem Human Subjects (PMHS) in a generic bucket seat environment. Three head positions, namely Normal (neutral), Zero Clearance between the head and head restraint, and Body Forward positions were tested. A high-speed x-ray system was used to record the motion of cervical vertebrae during these tests. Results demonstrate that: a) The maximum mean facet stretch at head restraint contact occurs at MS4 and MS5 for the Body Forward condition, b) The lower neck flexion moment, prior to head contact, shows a non-linear relationship with facet stretch, and c) "Differential rebound" during rear end impact increases facet stretch.
authors.affiliation: Ford Motor Company.
authors.forename: Srini
authors.initials: S
authors.lastname: Sundararajan
authors.forename: Priya
authors.initials: P
authors.lastname: Prasad
authors.forename: Constantine K
authors.initials: CK
authors.lastname: Demetropoulos
authors.forename: Scott
authors.initials: S
authors.lastname: Tashman
authors.forename: Paul C
authors.initials: PC
authors.lastname: Begeman
authors.forename: King H
authors.initials: KH
authors.lastname: Yang
authors.forename: Albert I
authors.initials: AI
authors.lastname: King