title: Prehospital emergency removal of football helmets using two techniques.
abstract: OBJECTIVE
  To compare the Eject Helmet Removal (EHR) System with manual football helmet removal.
  
  
  METHODS
  This quasiexperimental counterbalanced study was conducted in a controlled laboratory setting. Thirty certified athletic trainers (17 men and 13 women; mean ± standard deviation age: 33.03 ± 10.02 years; height: 174.53 ± 12.04 cm; mass: 85.19 ± 19.84 kg) participated after providing informed consent. Participants removed a Riddell Revolution IQ football helmet from a healthy model two times each under two conditions: manual helmet removal (MHR) and removal with the EHR system. A six-camera, three-dimensional motion capture system was used to record range of motion (ROM) of the head. A digital stopwatch was used to time trials and to record a split time associated with EHR system bladder insertion. A modified Borg CR10 scale was used to measure the rating of perceived exertion (RPE). Mean values were created for each variable. Three pairwise t-tests with Bonferroni-corrected alpha levels tested for differences between time for removal, split time, and RPE. A 2 x 3 (condition x plane) totally within-subjects repeated-measures design analysis of variance (ANOVA) tested for differences in head ROM between the sagittal, frontal, and transverse planes. Analyses were performed using SPSS (version 18.0) (alpha = 0.05).
  
  
  RESULTS
  There was no statistically significant difference in perceived difficulty between EHR (RPE = 2.73) and MHR (RPE = 2.55) (t(29) = 0.76; p = 0.45; d = 0.20). Manual helmet removal was, on average, 28.95 seconds faster than EHR (t(29) = 11.44; p < 0.001). Head ROM was greater during EHR compared with MHR in the sagittal (t(29) = 4.57; p < 0.001), frontal (t(29) = 5.90; p < 0.001), and transverse (t(29) = 8.34; p < 0.001) planes. Head ROM was also greater during the helmet-removal portion of EHR in the frontal (t(29) = 4.44; p < 0.001) and transverse (t(29) = 5.99; p < 0.001) planes, compared with MHR. Regardless of technique, sagittal-plane head ROM was greater than frontal- and transverse-plane movements (F(2,58) = 241.47; p < 0.001).
  
  
  CONCLUSIONS
  Removing a helmet manually is faster and creates slightly less motion than removing a helmet using the Eject system. Both techniques were equally easy to use. Future research should analyze the performance of the Eject system in other styles of football helmets and in helmets used in other sports such as lacrosse, motorsports, and ice hockey.
authors.affiliation: Department of Kinesiology, University of New Hampshire, Durham, New Hampshire 03824, USA.
authors.forename: Erik E
authors.initials: EE
authors.lastname: Swartz
authors.forename: Adam E
authors.initials: AE
authors.lastname: Hernandez
authors.forename: Laura C
authors.initials: LC
authors.lastname: Decoster
authors.forename: Jason P
authors.initials: JP
authors.lastname: Mihalik
authors.forename: Matthew F
authors.initials: MF
authors.lastname: Burns
authors.forename: Cathryn
authors.initials: C
authors.lastname: Reynolds
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001265:Athletic Injuries; D002574:Cervical Vertebrae / Q000293:injuries; D006259:Craniocerebral Trauma; D004632:Emergency Medical Services / Q000379:methods*; D004867:Equipment Design; D005260:Female; D005538:Football / Q000293:injuries*; D006260:Head Protective Devices; D006305:Health Status Indicators; D006801:Humans; D008297:Male; D019838:Neck Injuries; D013124:Spinal Injuries; D013178:Sports Medicine / Q000295:instrumentation / Q000379:methods*