title: Comparison of the whiplash injury criteria.
abstract: Whiplash injury criteria are based upon the hypothesis that neck injuries are caused by excessive loads, displacements, or head/T1 relative acceleration and velocity. The objectives of this study were to evaluate and compare the whiplash injury criteria (IV-NIC, NIC, Nkm, Nij, and NDC) during simulated rear impacts of a new Human Model of the Neck (HUMON) with and without an active head restraint (AHR). HUMON consisted of a neck specimen mounted to the torso of BioRID II and carrying an anthropometric head stabilized with muscle force replication. HUMON was seated and secured in a Kia Sedona seat with AHR on a sled. Rear impacts (7.1 and 11.1g) were simulated with the AHR in five different positions followed by an impact with no HR. Statistical differences (P < 0.05) were determined in the peak NIC and NDC due to the AHR, as compared to no HR, and in the peak IV-NIC relative to physiologic limits. Linear regression analyses identified correlation between IV-NIC and NIC, Nkm, Nij, and NDC (R(2) > or = 0.35 and P < 0.001). The AHR caused significant decreases in peak NIC and NDC as compared to no HR. The IV-NIC identified significantly increased motion above the physiologic limit at the middle and lower cervical spine with and without the AHR. Correlation was observed between IV-NIC and NIC, Nkm, Nij, and NDC. Extrapolation using the present correlations and the IV-NIC injury thresholds suggests neck injuries may occur at peak NIC of 14.4m(2)/s(2), Nkm of 0.33, or Nij of 0.09. Nonphysiologic spinal rotation at one or more spinal levels may occur even if head/T1 motions are small.
authors.affiliation: Biomechanics Research Laboratory, Department of Orthopaedics and Rehabilitation, Yale University School of Medicine, 333 Cedar Street, P.O. Box 208071, New Haven, CT 06520-8071, USA. paul.ivancic@yale.edu
authors.forename: Paul C
authors.initials: PC
authors.lastname: Ivancic
authors.forename: Daohang
authors.initials: D
authors.lastname: Sha
mesh_terms: D000054:Acceleration; D000063:Accidents, Traffic; D001696:Biomechanical Phenomena; D003198:Computer Simulation; D019416:Head Movements / Q000502:physiology; D006801:Humans; D008954:Models, Biological; D012149:Restraint, Physical; D014911:Whiplash Injuries / Q000175:diagnosis* / Q000503:physiopathology