Most individuals who watch sports have seen the falls players take in the course of the game and hear the sports announcers nearly wince when they announce the player sustained an ACL tear. This is one of the most common knee injuries. Those who participate in highly physical sports like soccer, basketball and football are the most likely athletes to injure the ACL.
Responsibility of the ACL in the Knee
The anterior cruciate ligament (ACL) is one of the four major knee ligaments that connect the tibia to the femur. The ACL is positioned inside the knee and runs diagonally through the middle. It is responsible for making sure that the tibia does not slide out of place. It also provides rotational stability in the knee. The ACL is positioned between the menisci which work like shock absorbers to help reduce stress between the femur and tibia.
Symptoms of an ACL Tear
While there are other ligaments in the knee, the ACL is the most commonly injured ligament. Annually there are approximately 200,000 ACL injuries in the US; and about 100,000 reconstructions performed each year. About half of the ACL injuries occur along with damage to other areas of the knee including the other ligaments and the meniscus. Many times there when an ACL injury occurs the bones in the knee are bruised as well. When the ACL tears it affects the stability of the knee joint and many complain that the knee just “gives out” on them. When the ACL is injured it is typical for the knee to swell and it may be too painful to put any weight on it. Some people say that they heard or felt a “pop” when the initial injury occurred. There are some common ACL injuries, but when the ACL actually tears, it cannot be sown back together. It has to be replaced with new tendon taken from another portion of the knee or leg.
Causes of an ACL Tear
Only about a third of the ACL injuries are a result of coming in contact with other players or objects. The other 70 percent happen without contact with an outside force. The ACL can be torn when an athlete makes a sudden turn and decelerates at the same time, while pivoting, or landing in an awkward position. In some sports, women are more likely to tear the ACL than men.
Preventing an ACL Injury
There are some ways to help reduce the chances that an ACL injury or tear will occur. Strength and stability exercises, plyometric exercises, aerobic conditioning and exercises that help improve balance can all be beneficial. Especially women athletes can benefit from exercises that strengthen the hamstrings and the quadriceps. Many sports include jumping which can make it more likely that you will sustain an injury therefore, it is important to learn how to land properly and safely. Many times the ACL tears or is injured when the knee collapses inward when landing on a jump. Learning the proper technique and proper strengthening of the hip muscles can be beneficial in reducing the risk. Always make sure that the gear you are using is properly adjusted. This is particularly true for skiers. The skis need to be adjusted correctly so that they release properly when there is a fall.
When to see a Doctor
With any type of knee injury it is always wise to have it checked out by a medical professional. They can run the proper diagnostic tests to determine what type of injury has occurred and determine its severity. They can explain treatment options and proper care of a knee injury as well as recommend a specialist or surgeon if needed.