title: Intentional versus unintentional contact as a mechanism of injury in youth ice hockey.
abstract: BACKGROUND
  Youth ice hockey injury rates and mechanisms have been described by various classification systems. Intentional versus unintentional contact was used to classify mechanisms of injuries. All injuries (n=247) in one youth hockey programme over a 5-year period were recorded and included in the analysis.
  
  
  OBJECTIVE
  To evaluate youth ice hockey injuries and compare programmes that allow body checking versus programmes that do not allow body checking. A primary goal was to determine whether programmes that allow body checking have increased injury rates from intentional body contact. Another goal was to describe the rates of injury across ages, levels of competitive play and during games versus practices.
  
  
  METHODS
  Rates of injury were compared for three levels of competition (house, select and representative) for approximately 3000 boys aged 4-18 years over a 5-year period. This represents 13 292 player years. Data were collected prospectively in this cohort study. All injuries were reported prospectively by a designated team official and verified by a physician. The log injury rate (per 1000 player hours) was modelled via Poisson regression with log player hours used as an offset. Rate ratio was used to explain the covariate-adjusted injury rate for each of three groups (all injuries, intentional injuries, unintentional injuries).
  
  
  RESULTS
  Unintentional contacts accounted for 66.0% of overall injuries (95% CI 60.0 to 72.0), compared with 34.0% from intentional contacts (p<0.001; Z=5.25). Serious injuries (fractures, dislocations, concussions) resulted more often from unintentional collisions (p=0.04). Players in more competitive leagues that allow body checking had a greater incidence of total injuries than less competitive leagues.
  
  
  CONCLUSIONS
  Most injuries in the youth hockey programme studied were the result of unintentional contact, and were generally more severe. These findings were not expected given previously published research.
authors.affiliation: Department of Orthopaedics, University at Buffalo, Buffalo, NY 14214, USA. sdarling@buffalo.edu
authors.forename: Scott R
authors.initials: SR
authors.lastname: Darling
authors.forename: Douglas E
authors.initials: DE
authors.lastname: Schaubel
authors.forename: John G
authors.initials: JG
authors.lastname: Baker
authors.forename: John J
authors.initials: JJ
authors.lastname: Leddy
authors.forename: Leslie J
authors.initials: LJ
authors.lastname: Bisson
authors.forename: Barry
authors.initials: B
authors.lastname: Willer
mesh_terms: D000293:Adolescent; D001265:Athletic Injuries / Q000453:epidemiology / Q000209:etiology; D001924:Brain Concussion / Q000209:etiology; D002648:Child; D002675:Child, Preschool; D050723:Fractures, Bone / Q000209:etiology; D006688:Hockey / Q000293:injuries* / Q000706:statistics & numerical data; D006801:Humans; D015994:Incidence; D004204:Joint Dislocations / Q000209:etiology; D008297:Male; D009864:Ontario / Q000453:epidemiology; D011446:Prospective Studies; D013180:Sprains and Strains / Q000209:etiology