title: Concussion incidence and time lost from play in the NHL during the past ten years.
abstract: BACKGROUND
  The problem of concussions in professional hockey has attracted much recent attention. To evaluate the current state of this injury in the National Hockey League (NHL), we analyzed the concussion incidence and time lost from play due to concussions during the past ten NHL seasons.
  
  
  METHODS
  Data were obtained from a complete review of injury reports in two different sports media sources covering the NHL seasons 1997-98 through 2007-08. Time lost from play was measured in missed games per concussion.
  
  
  RESULTS
  The incidence of concussions reported in the regular season ranged from a high of 1.81/1000 athlete exposures in 1998-99 to a low of 1.04/1000 athlete exposures in 2005-06. There was a downward trend in the number of concussions reported per season during the past ten years (p=0.01). However, average time lost from play per concussion increased over the same period (p<0.0005). Forwards suffered a disproportionately high percentage of concussions (p<0.0001).
  
  
  CONCLUSIONS
  Possibly related to injury reduction efforts, the number of concussions reported per season in the NHL has trended downward in recent years. However, the incidence of concussion remains high and the average time lost from play per concussion has increased. This may reflect increased injury severity in recent years or, alternatively, increased adherence to modern management guidelines preventing premature return to play.
authors.affiliation: Division of Neurology, Krembil Neuroscience Centre, Toronto Western Hospital, University of Toronto, Ontario, Canada.
authors.forename: Richard A
authors.initials: RA
authors.lastname: Wennberg
authors.forename: Charles H
authors.initials: CH
authors.lastname: Tator
mesh_terms: D000328:Adult; D001265:Athletic Injuries / Q000453:epidemiology*; D001924:Brain Concussion / Q000453:epidemiology*; D017408:Guidelines as Topic / Q000592:standards; D006688:Hockey / Q000706:statistics & numerical data* / Q000639:trends; D006801:Humans; D015994:Incidence; D012044:Regression Analysis; D012307:Risk Factors; D017751:Safety Management / Q000639:trends; D018582:Sick Leave / Q000706:statistics & numerical data / Q000639:trends; D019876:Sports Equipment / Q000009:adverse effects; D013997:Time Factors; D055815:Young Adult