Injuries to the anterior cruciate ligament, or ACL, are very common among athletes, particularly those participating in high-impact sports like soccer, football, and basketball. The ACL is one of the most commonly injured areas of the knee. Depending on the severity of the injury, surgery may be necessary in order for the athlete to regain full function of the knee.

Anatomy of the Knee

In order to understand how ACL injuries can happen, it helps to know about the anatomy of the knee. The knee is made up of three bones: the femur (thighbone), the tibia (shinbone), and the patella (kneecap).

There are four primary ligaments that connect these bones, helping to keep the joint stable. The collateral ligaments are located on each side of the knee. The inner ligament is called the medial collateral ligament, and the outer ligament is called the lateral collateral ligament. These two ligaments control the sideways motion of the knee.

The cruciate ligaments are found on the inside of the knee, controlling the back and forth motion of the knee. They cross each other, forming an “X,” with the anterior cruciate ligament, or ACL, to the front, and the posterior cruciate ligament, or PCL, to the back. The ACL helps to keep the tibia in place, so that it does not slide out in front of the tibia. It also gives rotational stability to the knee.

Causes and Symptoms of ACL Injuries

Roughly half of all ACL injuries occur in conjunction with damage to other components in the knee, such as articular cartilage, meniscus, or other ligaments. The ACL may be sprained, meaning the ligament is stretched, possibly to the point that it is unable to help stabilize the knee. Sometimes, the ligament is stretched to the point that it tears. Generally, the ACL will split completely into two pieces, or come very close to a complete tear; partial tears in the ACL are rare.

There are several ways that an athlete can injure the ACL. For example, if an athlete is running, then suddenly changes direction, stops, or slows down, he or she may experience an ACL injury. Landing incorrectly from a jump, or experiencing direct contact or a collision, like a tackle during a football game, may also result in injury to the ACL.

If you have injured your ACL, you may feel your knee give out from under you. This is sometimes accompanied by a “popping” sound. You may also find that you have lost the full range of motion in your knee, and that walking is uncomfortable. Tenderness and pain can occur along the joint line, and within 24 hours of the injury, the knee will swell. Sometimes, the swelling and pain will go away without treatment, but your knee will likely be less stable than it was previously. It is always a good idea to rule out serious injury before trying to return to athletic activities, even if the swelling goes away on its own. If the ACL is injured, you risk damaging the knee further if you proceed without treatment.

Treatment of ACL Injuries

Most athletes with a torn ACL will need to have surgery in order to return to sports; a torn ACL will not heal without surgery. Older or less active individuals may be able to bypass surgery if the knee is still stable overall. For these patients, nonsurgical methods such as physical therapy and wearing a knee brace may be used.

Generally, the ACL cannot simply be stitched back together when it has torn. In order to surgically repair the ACL, the ligament will need to be reconstructed. During surgery, the torn ligament will be replaced with a tissue graft, which acts as a foundation to grow the new ligament. Tissue grafts are commonly taken from the patellar tendon, which is located between the kneecap and the shinbone, or from the hamstring tendon, located at the back of the thigh. The quadriceps tendon, which runs from the kneecap to the thigh, is also used occasionally, and a cadaver graft, or allograft, can be used as well. Your doctor will help to determine which option is best for you.

Generally, the surgery will be delayed in order to allow for inflammation to decrease. ACL repair surgery is done arthroscopically, using a small camera called an arthroscope to see inside the joint. This allows the surgeon to perform the surgery using a smaller incision than what would be required for an open surgery. Because arthroscopic surgery is less invasive, it can result in less pain, a shorter hospital stay, and a faster recovery time.

Following surgery, you will need to participate in physical therapy to regain motion and strengthen the knee. Although arthroscopic surgery can help to speed up recovery time, it may be as long as six months or more until an athlete can return to sports, as it takes time for the ligament to regrow.

ACL Injury Treatment in Las Vegas, NV

Dr. Randa Bascharon has extensive experience in sports medicine, working with both professional and amateur athletes. For information about ACL surgery, or to schedule and appointment, please contact our office at (702) 947-7790.