Female athletes appear to suffer a higher incidence of ACL ruptures than males. What are the reasons for this?
"To answer this question, you first have to understand how and when ACL tears occur. ACL tears usually occur during competitive situations, not when the athlete is doing solo activities. Typically, the athlete is hurt when reacting to an unexpected situation. Sometimes it is when the athlete is planting his or her foot to change directions or is landing from a jump. Whatever the circumstances, the athlete mistimes the foot plant, and the forces generated across the knee joint causes the ACL to tear.
"Research has shown that women, on average, have smaller ACLs than men. Therefore, given the same forces, a smaller ACL would be more likely to tear. Interestingly, in my ACL-reconstructed patients, who all receive a 10mm wide ACL graft, there is no difference in the ACL graft tear rate between men and women after surgery, even in a group of highly competitive athletes who returned to their respective sports.
"Unfortunately, this factor of ACL size is not something that can be changed. There are many types of ACL prevention programs being recommended to female athletes. These programs involve doing agility, plyometrics, and strengthening exercises, all of which are performed in controlled situations. ACL tears, however, do not occur in controlled situations. I still perform more ACL reconstructions on men than women (70% versus 30%). If these prevention programs are effective, then they should prevent ACL tears in men as well. Any athlete, male or female, who has a small ACL is at higher risk for ACL injury than athletes with larger ACLs. It just so happens that more women than men have small ACLs."