Here's a great article we found on ACL Injury Prevention from Dr. Kevin McIntyre of Burlington Sports Therapy.  What makes this article great is it concisely describes common causes of ACL injuries, who is most likely to suffer from an ACL injury, and tips to prevent an ACL injury.

Last June we posted an entry on the prevention of anterior cruciate ligament (ACL) injuries. In that article, we learned that muscular co-contraction was very helpful in preventing an acute tear of this ligament. Today's blog is going to review some of the more current understandings in sports medicine with respect to ACL injury and prevention, including some practical ways that coaches, parents and players can help identify those athletes at risk.

Most ACL injuries are non-contact, occurring during deceleration, landing or pivoting. In soccer, 58% of injuries are non-contact.  Athletes who run and change direction in a more upright position are at more risk of ACL injury.

Females are 4 to 6 times more likely to injure their ACL (some of the points below will help to explain this difference).  Hormonal changes have been shown to influence ligaments (like the ACL).  Such hormonal changes occur during monthly cycles and growth spurts.

Having “loose” joints can predispose you to ACL injury. For example, a positive measure of knee hyperextension increases the odds of anterior cruciate ligament injury status five-fold.  Greater knee laxity and increased general joint laxity are more prevalent in girls.  As boys get older there is a trend toward decreased joint flexibility and ligament laxity. Relative to boys, girls show more joint flexibility and ligament laxity with age.

A trend toward knee valgus (pictured below) has been well established in the literature as a risk factor of ACL injury.  Females tend to land from jumping in a more valgus position than males.  They also tend to land harder, suggesting less muscular recruitment and thereby less stabilization of the knee.

Prevention of ACL injuries would significantly reduce the chances of arthritis in adulthood. There is an estimated ten fold increase (incidence) after ligament injury.

Active and passive flexibility training may be contraindicated for preventing ACL injuries. Flexibility training does not provide protective effects from injury as has been previously reported in the literature.

Prevention works.  According to a recent study of 1435 female varsity soccer players, those who did the proper preventative exercises showed a 3 fold reduction in non-contact ACL tears.  There is a growing body of research validating ACL prevention programs.

[caption id="" align="alignnone" width="352" caption="Prevent ACL Knee Injuries"]Prevent ACL Knee Injuries[/caption]