Anterior cruciate ligament injury in elite football: a prospective three-cohort study

Abstract

Anterior cruciate ligament (ACL) injury causes long lay-off time and is often complicated with subsequent new knee injury and osteoarthritis. Female gender is associated with an increased ACL injury risk, but few studies have adjusted for gender-related differences in age although female players are often younger when sustaining their ACL injury.The objective of this three-cohort study was to describe ACL injury characteristics in teams from the Swedish men's and women's first leagues and from several European men's professional first leagues. Over a varying number of seasons from 2001 to 2009, 57 clubs (2329 players) were followed prospectively and during this period 78 ACL injuries occurred (5 partial). Mean age at ACL injury was lower in women compared to men (20.6 ± 2.2 vs. 25.2 ± 4.5 years, p=0.0002).Using a Cox regression, the female-to-male hazard ratio (HR) was 2.6 (95% CI 1.4 to 4.6) in all three cohorts studied and 2.6 (95% CI 1.3 to 5.3) in the Swedish cohorts; adjusted for age, the HR was reduced to 2.4 (95% CI 1.3 to 4.2) and 2.1 (95% CI 1.0 to 4.2), respectively. Match play was associated with a higher ACL injury risk with a match-to-training ratio of 20.8 (95% CI 12.4 to 34.8) and 45 ACL injuries (58%) occurred due to non-contact mechanisms. Hamstrings grafts were used more often in Sweden than in Europe (67% vs. 34%, p=0.028), and there were no differences in time to return to play after ACL reconstruction between the cohorts or different grafts. In conclusion, this study showed that the ACL injury incidence in female elite footballers was more than doubled compared to their male counterparts, but also that they were significantly younger at ACL injury than males. These findings suggest that future preventive research primarily should address the young female football player.

Applied Physiology of Female Soccer: An Update

“…Longitudinal injury patterns in female soccer are of interest to assess if soft tissue injuries are becoming more frequent as the intensity of the female game increases or if the increased Soccer injuries predominately affect the ankle, knee and muscles of the thigh and calf [101]. Injuries to the hip and groin are less common in female players [98,103,106,109,110] [75,98,99,115,116]. The large body of evidence is in part due to the financial and emotional cost of an ACL as well as the potential impact upon the team [117].…”

“…Knee injuries in females are well documented [103] with ligament injuries, specifically injury to the anterior cruciate ligament (ACL) predominant in the literature [75,98,99,115,116]. The large body of evidence is in part due to the financial and emotional cost of an ACL as well as the potential impact upon the team [117].…”

“…The large body of evidence is in part due to the financial and emotional cost of an ACL as well as the potential impact upon the team [117]. Female athletes are reported to have between 2 and 6 fold higher incidence of non-contact ACL injury than their male counterparts [115,118]. In soccer, this has been translated to ACL injury rates of 0.4 and 0.7 injuries per season in males and females respectively [115].…”

“…Female athletes are reported to have between 2 and 6 fold higher incidence of non-contact ACL injury than their male counterparts [115,118]. In soccer, this has been translated to ACL injury rates of 0.4 and 0.7 injuries per season in males and females respectively [115]. Match-play poses a substantially higher risk of ACL injury compared to training (0.09 per 1000 hours versus 0.90 per 1000 hours respectively) [107].…”

“…One study has revealed that the use of the OCP (during the withdrawal phase) has been shown to elicit significantly lower reactive strength index scores during a drop jump. Injury data in female players has largely focussed on ACL injuries, as it is a recognised issue within female team sport athletes, with the incidence quoted as 2-6 times greater compared to males [115,118]. Numerous explanations exist for this increased incidence, some of which are anatomical [74,75,123], whilst others focus on dynamic differences in biomechanical loading and patterns of neuromuscular activation [118,124,126].…”