Anterior cruciate ligament rupture: differences between males and females.

The rate of anterior cruciate ligament (ACL) rupture is three times higher in female athletes than in male athletes. Intrinsic factors such as increased quadriceps angle and increased posterior tibial slope may predispose girls and women to ACL injury. Compared with males, females have smaller notch widths and smaller ACL cross-sectional area; however, no conclusive correlation between ACL size and notch dimension exists, especially in relation to risk of ACL injury. Female athletes who land with the knees in inadequate flexion and in greater-than-normal valgus and external rotation are at increased risk of ACL injury. No conclusive link has been made between ACL injury and the menstrual cycle. Neuromuscular intervention protocols have been shown to reduce the rate of injury in girls and women. Females are more likely than males to have a narrow A-shaped intercondylar notch, and special surgical considerations are required in such cases. Following ACL reconstruction, female athletes are more likely than male athletes to rupture the contralateral ACL; however, males and females are equally likely to rupture the reconstructed knee. Although self-reported outcomes in the first 2 years following reconstruction are worse for females than for males, longer-term studies demonstrate no difference between males and females.