title: Extrication collars can result in abnormal separation between vertebrae in the presence of a dissociative injury.
abstract: BACKGROUND
  Cervical collars are applied to millions of trauma victims with the intent of protecting against secondary spine injuries. Adverse clinical outcomes during the management of trauma patients led to the hypothesis that extrication collars may be harmful in some cases. The literature provides indirect support for this observation. The purpose of this study was to directly evaluate cervical biomechanics after application of a cervical collar in the presence of severe neck injury.
  
  
  METHODS
  Cranial-caudal displacements in the upper cervical spine were measured in cadavers from images taken before and after application of collars following creation of an unstable upper cervical spine injury.
  
  
  RESULTS
  In the presence of severe injury, collar application resulted in 7.3 mm +/- 4.0 mm of separation between C1 and C2 in a cadaver model. In general, collars had the effect of pushing the head away from the shoulders.
  
  
  CONCLUSIONS
  This study was consistent with previous evidence that extrication collars can result in abnormal distraction within the upper cervical spine in the presence of a severe injury. These observations support the need to prioritize additional research to better understand the risks and benefits of cervical stabilization methods and to determine whether improved stabilization methods can help to avoid potentially harmful displacements between vertebrae.
authors.affiliation: Spine Research Laboratory, Baylor College of Medicine, Houston, Texas 77030, USA.
authors.forename: Peleg
authors.initials: P
authors.lastname: Ben-Galim
authors.forename: Niv
authors.initials: N
authors.lastname: Dreiangel
authors.forename: Kenneth L
authors.initials: KL
authors.lastname: Mattox
authors.forename: Charles A
authors.initials: CA
authors.lastname: Reitman
authors.forename: S Babak
authors.initials: SB
authors.lastname: Kalantar
authors.forename: John A
authors.initials: JA
authors.lastname: Hipp
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002102:Cadaver; D002574:Cervical Vertebrae / Q000000981:diagnostic imaging / Q000293:injuries*; D005260:Female; D006801:Humans; D007103:Immobilization / Q000295:instrumentation*; D008297:Male; D008875:Middle Aged; D008954:Models, Biological; D019838:Neck Injuries / Q000000981:diagnostic imaging / Q000209:etiology* / Q000628:therapy; D009989:Orthotic Devices / Q000009:adverse effects*; D010360:Patient Transfer / Q000379:methods; D016059:Range of Motion, Articular / Q000502:physiology; D013124:Spinal Injuries / Q000000981:diagnostic imaging / Q000209:etiology* / Q000628:therapy*; D014057:Tomography, X-Ray Computed / Q000379:methods