What is an ACL injury?
An ACL injury is a tear of the anterior cruciate ligament, the primary stabilizer of the knee. The ligament is a band of tissue that connects the upper leg bone, the femur, to the lower leg bone, the tibia. ACL damage causes the knee to "give out," limiting or stopping mobility, and is a particular problem for athletes.
How does an ACL injury typically occur?
Most commonly, an ACL tear is sustained when a person stops running suddenly and twists or swivels a knee with feet fixed on the ground. Another way that it can occur is when the knee is stretched backward with too much force. In sports like football, the impact of twists and tackles are especially likely to cause an ACL injury. ACL injuries are also common among those who participate in contact or pivoting sports such as baseball, basketball and lacrosse.
How is an ACL injury treated?
For those who aren't actively participating in sports, physicians recommend bracing and physical therapy — treatments that strengthen surrounding muscles to support the knee and give the tear time to heal — as first-line therapies.
Athletes, especially those whose sports require pivoting, often opt for surgical repair or replacement of the damaged ligament to restore pre-injury strength and stability to the leg. The tissue used to replace the ligament may be taken from another part of the patient's knee or from a cadaver.
Many surgeons report that while ACL surgical repairs heal within six to nine months, an ACL graft takes a year to mature. This means that even with the best surgical replacement, most athletes will not be able to return to contact or pivoting sports for one year.
Are athletes truly competitive after an ACL injury?
Yes, most athletes can resume sports at a very high level after successful repair or ligament replacement. Many athletes are able to continue at a professional level, and some can count on long careers.
How has ACL treatment advanced over the years?
In the past, ACL injuries often meant the end of a competitive sports career for professionals and amateurs. Early surgical treatments were frequently unsuccessful and nonsurgical treatments often failed to fully restore strength and stability. Today's surgical intervention typically enables athletes to perform nearly as well as they did prior to surgery. A prime example is NFL running back Adrian Peterson, who returned to play after a bone-to-bone ligament graft and months of physical therapy. For nonathletes, nonsurgical treatment is usually effective, but surgical intervention is often a better choice for those who play demanding sports.