Epidemiology of football injuries

Abstract

Aim The overall aim of this on-going injury study is to increase the safety in football. Study design Prospective cohort survey. Methods The study population consisted of two cohorts: the Union of European Football Associations (UEFA) Champions League (UCL) cohort and the Swedish Superleague cohort. The UEFA Champions League cohort with 17 teams from nine countries was followed over five consecutive seasons (2001 to 2006). The Swedish Superleague with 14 teams was followed for two full consecutive seasons (2001 and 2002). Exposure for training and matches in the club and in national teams was registered in minutes for each player. The team doctor reported all injuries causing the player to miss at least one match or training session. The study follows the consensus on methods for studies on football injuries agreed upon by the Federation of International Football Associations (FIFA) and UEFA. Results Overall 6300 injuries have been registered during 800,000 h of exposure. The incidence of injury at top-level football is six to nine injuries per 1000 h of total exposure (three to five injuries per 1000 training hours and 24 to 30 injuries per 1000 match hours). As a mean, a team of 25 players can expect 40 to 50 injuries per season, half of them causing absence less than a week but six players of them causing absence more than a month. The risk of injury has not increased during the five-year period. Thigh muscle injury is the most common injury at top-level with an injury incidence of 1.6/1000 h of exposure, which means that a team can expect 10 such injuries each season. The risk of ankle sprain has been reduced by 50%, probably due to the thorough knowledge in top-level teams about optimal treatment and prevention. A correlation has been found between major injuries (causing absence > 4 weeks) and performance. There is a considerable variation in the number of matches played per season in European professional leagues. Top-level players are obliged to play many matches, especially during the final period of the season. A correlation was found between many matches at the end of a season and an increased injury risk and/or underperformance during subsequent world tournaments. Conclusion The injury risk has not increased in male professional football during recent years. At elite level, the risk of ankle sprain has been lowered and thigh muscle strain is the most common injury. A period with a congested match calendar can lead to fatigue increasing the risk of injury and poor performance during the following period.