One wrong twist of the knee can cause the common and painful ACL tear. The injuries generally occur without contact from another person and most often occur while the athlete is participating in basketball, gymnastics or soccer.
Female athletes have four to ten times more ACL injuries than male athletes have.
In general, women have wider pelvises than men, which impacts the angle of the knee, which could increase the risk of ACL injuries. However, studies have not demonstrated any consistent correlation between the knee alignment and ACL injury. In general, women have greater flexibility than men. Women basketball and soccer players have been shown to have greater ACL flexibility than their male counterparts. With more flexibility within the ligament, the ACL in women could twist much further and tear.