ACL injuries aren’t uncommon, but in most instances, the only time we hear about them is when a player in a traditionally male-dominated sport like football or basketball gets injured. As a result, many people tend to think of ACL injuries as happening far more often among men. But actually, the opposite is true. Women are far more likely to experience an injury to their ACL than men — about two to eight times as likely, according to research — and only now, researchers are beginning to understand why.
ACL injuries are a type of knee injury where the anterior cruciate ligament gets damaged. The ACL is one of four major ligaments in the knee. The other three are the posterior cruciate ligament, the medial collateral ligament, and the lateral collateral ligament. All four ligaments work together to help the knee function normally and to keep the joint stable. The anterior and posterior cruciate ligaments cross in the middle of the knee, with both ligaments controlling the way the knee bends.
ACL injuries are most often associated with sharp pivoting movements, like changing direction when running. The ligament can also be injured when it’s stretched or strained beyond its normal limits during a fall, car accident, or work-related injury.
Although they know women experience more ACL injuries than men, researchers aren’t exactly sure why that occurs. But they do agree that it’s probably due to a combination of factors.
Part of the reason why women have more ACL injuries may be because their knees are just “built” differently. The ACL rests in a groove in the knee joint. This groove helps keep the ligament moving the way it’s supposed to when you bend or flex your knee. In women, this groove tends to be narrower than in men, which means it may be more likely to “jump out” of the groove. ACL ligaments also tend to be thinner in women, which means impact or strain on the ligament is likely to cause more damage.
Anatomical differences in women’s knees mean they don’t respond the same way to nerve stimuli. As a result, women’s knees tend to be less able to adequately “brace” against impacts, making injury more likely. Muscular differences in women’s knees also cause their knees to be more “bent” when landing, which means the stress on the ACL is also increased.
Finally, some researchers think the differences in ACL injury rates might have to do with how women train and perform in sports and other physical activities. For instance, while men tend to rely mainly on their hamstring muscles (the muscles in the back of the thigh) for pivoting movements (the main cause of ACL tears), women are more likely to use their quadriceps muscles (the muscles in the front of the thigh). Plus, women tend to land with their feet flat rather than landing on the balls of their feet, which is more common among male athletes. Landing on the balls of the feet reduces strain on the knee, helping to prevent ACL injuries and other knee joint damage.
One of the best ways to prevent ACL injuries is to warm up adequately before any type of physical activity that uses your legs. Warming up with a few basic aerobic activities increases blood flow to your muscles so they’re less stiff — and therefore less prone to injury.
Stretching is also important. When you stretch your hamstrings and your quadriceps, you direct increased blood flow to those muscle groups, and you also “prime” the muscles and nerves for increased activity. It’s also a good idea to stretch your calves and your lower back as well.
Finally, make sure you use proper form when exercising or participating in a sport or other physical activity, and make sure you're training the right way too. Getting a little guidance from a physical trainer or rehab specialist is a good way to make sure you're doing all the right moves and none of the wrong ones.
What's one of the worst things you can do for knee pain? Ignore it. Delaying treatment will just make things worse — usually much worse. At Orange Orthopaedic, Dr. James Lee offers state-of-the-art treatment options for treating knee injuries, as well as guidance to help prevent problems in the future. If you’re having knee pain, don’t put off treatment. Book an appointment online today.