title: Correlation between neck injury risk and impact severity parameters in low-speed side collisions.
abstract: METHODS
  In vitro acceleration study on human cadaveric cervical spine specimens.
  
  
  OBJECTIVE
  To investigate the correlation between the risk to sustain a structural cervical spine injury and vehicle-related impact severity parameters.
  
  
  BACKGROUND
  Impact severity parameters, such as the peak acceleration of the vehicle, its mean acceleration, and its velocity change, are often used to predict the whiplash injury risk or to objectify the patient's symptoms even though their correlation to injury is still not well understood.
  
  
  METHODS
  In a series of three in vitro experiments, a total of 18 human cadaveric cervical spine specimens were subjected to incremental side accelerations until structural injury occurred. While the duration of the acceleration pulse was kept constant throughout all three experiments, its shape was varied: In Experiment I, the acceleration pulse had a fast increase up to the maximum value and a fast decrease down to zero (fast-fast). Experiment II was characterized by a slow increase and fast decrease (slow-fast), and Experiment III was characterized by a fast increase and a slow decrease (fast-slow).
  
  
  RESULTS
  The specimens of Experiment II (slow-fast) sustained structural injury at a significantly higher peak acceleration of the sled (4.6 g on average) than those of Experiments I (fast-fast) (2.6 g) and III (fast-slow) (3.1 g). In contrast, mean acceleration and velocity change of the injuring impacts were almost the same in all three experiments.
  
  
  CONCLUSIONS
  The injury risk to the cervical spine was predictable by the mean acceleration of the sled and since the duration of the crash pulses was constant also by its velocity change but not by its peak acceleration.
authors.affiliation: Institute for Orthopedic Research and Biomechanics, University of Ulm, Ulm, Germany. annette.kettler@medizin.uni-ulm.de
authors.forename: Annette
authors.initials: A
authors.lastname: Kettler
authors.forename: Kai
authors.initials: K
authors.lastname: Fruth
authors.forename: Erich
authors.initials: E
authors.lastname: Hartwig
authors.forename: Lutz
authors.initials: L
authors.lastname: Claes
authors.forename: Hans-Joachim
authors.initials: HJ
authors.lastname: Wilke
mesh_terms: D000054:Acceleration / Q000009:adverse effects; D000063:Accidents, Traffic; D000368:Aged; D000369:Aged, 80 and over; D002574:Cervical Vertebrae / Q000293:injuries; D005260:Female; D006801:Humans; D007403:Intervertebral Disc / Q000293:injuries; D017746:Joint Capsule / Q000293:injuries; D008297:Male; D009038:Motion; D019838:Neck Injuries / Q000453:epidemiology / Q000209:etiology*; D012306:Risk; D012421:Rupture / Q000209:etiology; D013124:Spinal Injuries / Q000453:epidemiology / Q000209:etiology*; D014911:Whiplash Injuries / Q000453:epidemiology / Q000209:etiology; D021801:Zygapophyseal Joint / Q000293:injuries