Wednesday, February 9

An ACL primer
by Dr. Robert Salis

In the past, tears of the anterior cruciate ligament, or ACL, almost always signaled the end of a career for the college or professional athlete, especially one engaged in contact and collision sports, such as football and basketball. However, recent surgical and rehabilitation techniques have given hope to athletes with this injury.

The knee joint is primarily held together with four ligaments. These ligaments connect the femur (thigh bone) to the tibia (shin bone), and allow the knee to flex and twist while preventing excessive front-to-back and twisting motion between the two bones. The ACL is the most important of the four ligaments for knee stability. (The other ligaments are the posterior cruciate, medial collateral and lateral collateral ligaments).

The ACL almost always ruptures suddenly. The tears are generally not the result of repeated pounding -- most often, the injury occurs when a player "plants" or pushes off with the knee bent or in rotation. Some tears occur during a collision or from a direct blow. Professional basketball players Danny Manning and Ron Harper tore their ACL several years ago while they were going in for uncontested lay-ups -- moves they had made hundreds of times before.

Typical symptoms include a "pop" felt in the knee, followed by immediate pain and swelling. The pain may be so severe that the player will feel nauseated and vomit. Sometimes players may have mild pain and swelling. Because of the range of symptoms, a physician should always evaluate the player

ACL treatments
Previous treatment for a torn ACL, with or without surgery, has been frequently unsuccessful. Recent advances in surgical techniques used to repair the torn ligament have now made it possible for many NBA and NFL stars to return to a high level of play. Bernard King was the first NBA player to tear his ACL and return to near the same performance level after his 1995 surgery. Since then, scores of basketball players, including Manning and Harper, and professional football players, such as Barry Sanders and Ty Detmer, have returned to a high level of play after having surgery to repair torn ACLs.

The most common surgical technique used to repair the ACL involves screwing a piece of the patellar tendon (which connects the knee cap, or patella, to the tibia) into place where the ruptured ACL had been. This surgery is accomplished with the help of an arthroscope and a small knee incision. The tendon takes the place of the ACL and returns stability to the knee joint. Because the composition of the patellar tendon graft is not exactly the same as the injured ligament, it is unlikely the knee will return to pre-injury strength. However, that does not mean it won't allow for the high level of function required for competitive sports.

Some players may choose to avoid surgery and simply strengthen the leg through rehabilitation exercises (most often hamstring strengthening exercises). NBA basketball star Sean Elliott, of the San Antonio Spurs, partially tore his ACL when he was 14. He has competed successfully without surgery. People generally can walk and run without an intact ACL, but sudden cutting and twisting is often difficult. For this reason, most high-level football and basketball players who wish to continue competing may be better served having a torn ACL reconstructed. Studies show that more than 50 percent of players with a torn ACL will have recurrent problems with swelling and collapse of the knee. These problems can lead to cartilage damage and eventual arthritis in the involved knee.

The most difficult part about having ACL surgery is the extensive rehabilitation. The process begins with getting one's range of motion back, followed by extensive strengthening exercises. In the typical program, it usually takes the player about a year before he or she can return to a high level of competition. However, with determination and a diligent rehabilitation program, players can usually return to near pre-injury form.

Dr. Robert Salis is co-director of the Sports Medicine Fellowship at Kaiser Permanente Medical Center in Fontana, Calif. He also serves as team physician at Pomona College in Claremont and is an associate clinical professor of Family Medicine within the UCR/UCLA Biomedical Sciences Program.

The information, including opinions and recommendations, contained in this website is for educational purposes only. Such information is not intended to be a substitute for professional medical advice, diagnosis or treatment. No one should act upon any information provided in this website without first seeking medical advice from a qualified medical physician.

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