title: Results of 2 decades of injury surveillance and public release of data in the Australian Football League.
abstract: BACKGROUND
  Injuries are common in all professional football codes (including soccer, rugby league and union, American football, Gaelic football, and Australian football).
  
  
  OBJECTIVE
  To report the epidemiology of injuries in the Australian Football League (AFL) from 1992-2012 and to identify changes in injury patterns during that period.
  
  
  METHODS
  Descriptive epidemiology study.
  
  
  METHODS
  The AFL commenced surveying injuries in 1992, with all teams and players included since 1996. An injury was defined as "any physical or medical condition that causes a player to miss a match in the regular season or finals (playoffs)." Administrative records of injury payments (which are compulsory as part of salary cap compliance) to players who do not play matches determined the occurrence of an injury. The seasonal incidence was measured in units of new injuries per club (of 40 players) per season (of 22 matches).
  
  
  RESULTS
  There were 4492 players listed over the 21-year period who suffered 13,606 new injuries/illnesses and 1965 recurrent injuries/illnesses, which caused 51,919 matches to be missed. The lowest seasonal incidence was 30.3 new injuries per club per season recorded in 1993, and the highest was 40.3 recorded in 1998. The injury prevalence (missed matches through injury per club per season) varied from a low of 116.3 in 1994 to a high of 157.1 in 2011. The recurrence rate of injuries was highest at 25% in 1992 and lowest at 9% in 2012 and has steadily fallen across the 21 years (P < .01). The most frequent and prevalent injury was hamstring strain (average of 6 injuries per club per season, resulting in 20 missed matches per club per season; recurrence rate, 26%), although the rate of hamstring injuries has fallen in the past 2 seasons after a change to the structure of the interchange bench (P < .05). The rate of knee posterior cruciate ligament injuries fell in the years after a rule change to prevent knee-to-knee collisions in ruckmen (P < .01).
  
  
  CONCLUSIONS
  Annual public reporting (by way of media release and reports available freely online) of injury rates, using units easily understood by laypeople, has been well received. It has also paved the way for rule changes with the primary goal of improving player safety.
authors: John W. Orchard, University of Sydney, School of Public Health, Cnr Western Avenue & Physics Road, NSW 2006 Sydney, Australia. john.orchard@sydney.edu.au
authors: John W
authors: JW
authors: Orchard
authors: Hugh
authors: H
authors: Seward
authors: Jessica J
authors: JJ
authors: Orchard
mesh_terms: D000293:Adolescent; D000328:Adult; D001265:Athletic Injuries / Q000453:epidemiology*; D001315:Australia / Q000453:epidemiology; D005538:Football / Q000293:injuries*; D006801:Humans; D015994:Incidence; D011159:Population Surveillance; D012008:Recurrence; D055815:Young Adult