The epidemiology of anterior cruciate ligament injury in football (soccer): a review of the literature from a gender-related perspective

Football (soccer), the most popular sport worldwide, is associated with a high injury risk, and the knee joint is often affected. Several studies have found female players to be more susceptible to knee injury, anterior cruciate ligament (ACL) injury in particular, compared to their male counterparts. There is, however, some controversy regarding the magnitude of this risk increase and a few studies have found no differences. The influence of age and activity type on gender-related differences in injury risk is only scarcely investigated. In this paper, the literature reporting gender-specific ACL injury risk in football is reviewed. A literature search yielded 33 relevant articles that were included for review. These show that female players have a 2-3 times higher ACL injury risk compared to their male counterparts. Females also tend to sustain their ACL injury at a younger age than males, and a limiting factor in the existing literature is that age is not adjusted for in comparisons of ACL injury risk between genders. Furthermore, the risk increase in females is primarily evident during match play, but type of exposure is also rarely adjusted for. Finally, the studies included in this review share important methodological limitations that are discussed as a starting point for future research in the field.