The anterior cruciate ligament (ACL) is one of the two cross-shaped (cruciate) ligaments located within the knee joint and which cross over each other as they run diagonally between the thigh and leg bones, providing additional support, preventing overbending and overstraightening of the knee, and limiting sliding movement between the bones.
An ACL tear occurs most often during sports. ACL tears can also occur during rough play, mover vehicle collisions, falls, and work-related injuries. About 80% of sports-related ACL tears are “non-contact” injuries. Most often ACL tears occur when pivoting or landing from a jump. The knee gives-out from under the athlete when the ACL is torn.
The ACL is one of the most commonly injured ligaments of the knee in women participating in competitive sports. Why women are more prone to ACL injury then men is still unknown.
Symptoms of an ACL tear include:
- An audible pop at a moment of injury
- Knee tends to slip out of joint, feels unstable, and swelling and pain hinder movement
- Knee often feels as though it will give way or is unstable
Only about a third of people with a completely torn ACL are able to build their muscle strength enough to resume normal activities without surgery. Still, the non-operative option exists, and having surgery or forgoing it is partly a personal choice. Active, athletic people are more likely to opt for surgery, so that the knee can be repaired and rehabilitated and they can return to their activities.
The surgery is called an endoscopic ACL reconstruction and is done using small instruments through a Band-Aid size incision. It is done either on an outpatient basis or you may have to spend the night in the hospital. After four to six months, you should be able to return to unrestricted activity and competitive sports.
Those who are not very active may choose a strengthening program instead of surgery, since the injury is not likely to interfere with their daily activities. Such a program takes about six to 10 months to complete. However, about 65 percent of all patients with a torn ACL will eventually develop a torn meniscus — a protective cartilage that reduces friction between the knee bones — which may predispose them to early onset arthritis.