Female athletes are known to have a higher risk of injuring their anterior cruciate ligament, or ACL, while participating in competitive sports. Unfortunately, understanding why women are more prone to ACL injury is unclear.
Several studies have been done to investigate ACL tears in female atheltes, and what is well known is that in sports that place a significant demand on the ACL, such as basketball, soccer, cheerleading, and others, ACL injuries are up to ten times more common in women than in men.
It's no secret that men and women are built differently, have differently shaped skeletons, and have unique body types. But no one knows exactly what causes ACL injuries to be so much more common in women.
Some theories are:
- Anatomic Differences
There are many anatomic differences between men and women, including pelvis width, Q-angle, size of the ACL, and size of the intercondylar notch (where the ACL crosses the knee joint). Limited studies have shown a difference in these factors, but not an ability to predict individuals who will sustain an ACL tear.
- Hormonal Differences
It is known that the ACL has hormone receptors for estrogen and progesterone, and it has been thought that hormone concentration could play a role in ACL injuries. This was a popular theory, but most scientists agree that menstrual cycle has little effect, if any at all, on the likelihood of ACL tear.
- Biomechanic Differences
Stability of the knee is dependent on different factors. The two most important are the static and the dynamic stabilizers of the knee. The static stabilizers are the major ligaments of the knee, including the ACL. The dynamic stabilizers of the knee are the muscles and tendons that surround the joint. Women have been found to have differences in biomechanic movements of the knee seen when pivoting, jumping, and landing -- activities that often lead to an ACL injury.
Should women do anything to prevent ACL tears?
Neuromuscular training programs can lower the risk of ACL injury in female athletes. Prevention of ACL tears has been shown to be effective with the utilization of these neuromuscular training programs. These programs teach athletes muscles to better control the stability of their joints. Studies have shown when women perform these neuromuscular training programs, their risk of ACL tears drops down to the risk of men tearing their ACL (about an eightfold drop in risk).
"Slauterbeck J, et al. "ACL injuries in women: Why the gender disparity and how do we reduce it?" Orthopaedics Today 23:1, July 2003.
Griffin LY, et al. "Noncontact Anterior Cruciate Ligament Injuries: Risk Factors and Prevention Strategies" J. Am. Acad. Ortho. Surg., May/June 2000; 8: 141 - 150.
Hewett TE, et al. "The effect of neuromuscular training on the incidence of knee injury in female athletes: A prospective study." Am J Sports Med 1999;27:699–706.