ACL Injury Prevention

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.

valgus knee1 ACL Injury Prevention

Prevent ACL Knee Injuries


Can I still ski if I have a torn ACL?

Our Brace Coaches are often asked by skiers if it’s possible to ski after they’ve suffered from an ACL injury.  The answer is yes, but a skier will need to take some steps to ensure their knee is well protected on the slopes.  The first thing you’ll want to do is meet with your doctor and make sure skiing won’t further damage your knee.  The next step will be to strengthen the muscles in your knee, which will help protect you knee joint from further injuries.  The last step  to take would be to wear a protective knee brace to ensure maximum stability for your knee joint while skiing.  Check out our article on skiing with a torn ACL for additional recommendations, including the recommendations on which knee brace to wear.

Prevent ACL injuries in Football

football1 200x300 Prevent ACL injuries in Football

Common Football Injuries - Torn ACL

With football season drawing to a close, there are many players out there suffering from a torn or ruptured ACL – one of the most common football injuries.  A torn ACL can drastically affect his ability to play the sport as coordination and mobility can both be drastically impaired. Players like Willis McGahee, Donovan McNabb, and Dante Culpepper have all had their careers impacted by torn ACL injuries.

As disastrous as this injury can be for a football player, prevention is the best way to avoid sitting on the sidelines for the remainder of the season.   A knee brace is one of the best options for ACL injury prevention.  Many colleges and professional football teams are turning to the DonJoy Armor Knee Brace with FourcePoint hinge.  Check out this article to see why the Armor brace with FourcePoint hinge is great at preventing an ACL injury in football players.

ACL Injuries in Skiers

skiing knee braces ACL Injuries in Skiers

Skiing Knee Braces

Knee injuries while skiing is a hot topic as the ski resorts are getting ready to open for the season.  Researchers are also trying to reconcile conflicting findings about gender as a risk factor for injury. Investigators from Oslo analyzed a single season of data for nine World Cup alpine ski teams and found a higher rate of injury for men than women (11 vs. 5.4 injuries per 1000 runs).5 However, all 14 of the ACL injuries reported occurred in female skiers, according to Tone Bere, a researcher in the Oslo Sports Trauma Research Center.

The Oslo results about ACL and gender are consistent with those of Vermont researchers, whose 1998 survey-based study of competitive alpine ski racers6 found that female skiers are 2.3 times more likely to experience a knee injury and 3.1 times more likely to experience an ACL disruption than their male counterparts. But a 1999 study7 from the Steadman Hawkins Sports Medicine Foundation in Vail, CO, found that the incidence of ACL injury among ski patrollers or instructors does not differ significantly between men and women (4.2 vs 4.4 injuries per 100,000 skier-days), suggesting that gender may be more significant as a risk factor for competitive skiers than for skiing pros.

Of course, the primary mechanism of ACL injuries in skiers is not in question. That would be the “phantom foot” scenario, in which a skier falls backwards in such a way that the load on the ACL causes the ligament to rupture (called phantom foot because the downhill ski produces a force as if an imaginary foot were pushing on its tail). The bindings that connect the boot to the ski are designed to release when excessive levels of force are experienced, but because the ski boot typically pivots around an axis near its heel, the bindings are better able to sense loads applied at the front of the ski than those applied at the back (as in a phantom foot fall).

“What the leg feels and what the binding feels are not the same thing,” said Carl F. Ettlinger, MME, an adjunct assistant professor in orthopedics and rehabilitation at UVM and a keynote speaker in Tromsö. “We don’t necessarily have an idealized binding, one that was designed for today’s skiers.”

That may be about to change. Former competitive skier Rick Howell has designed a knee-friendly binding that features a virtual second pivot point to better respond to torque generated during phantom foot falls, as well as force-filtering technology that differentiates skiing-related forces from potentially injurious forces to minimize inadvertent binding release.

A study8 that validates the new device, called KneeBinding, was presented in July 2007 at the International Society for Skiing Safety (ISSS) conference in Aviemore, Scotland. KneeBinding is expected to be available for the upcoming ski season.

In the meantime, Johnson, Ettlinger, and others are working to promote ACL awareness among skiers, including knee-friendly techniques for skiing, falling, and recovering from falls (see vermontskisafety.com).

They also recommend against the more-is-better approach to tightening bindings far beyond the typical range of release settings, also known as DIN settings (typical range, four to 12). Instead of preventing injury, release settings that are too high tend to result in bindings that fail to release when they should.

“Some competitors’ bindings go up into the 20s and 30s, and there isn’t any way out at that point,” said congress keynote speaker Jasper Shealy, PhD, professor emeritus of industrial and systems engineering at the Rochester Institute of Technology in New York. “It’s really gotten way out of order.”

from Biomechnics Magazine November/December 2008 by Jordana Bieze Foster

Do you suffer from a skiing knee injury?  Shop our selection of knee braces for skiing.  Wearing a knee brace while skiing can help stabilize your knee and prevent injuries.