ACL injuries are among the most common sport related knee injuries. Approximately 100,000 to 200,000 people in the United States acquire a torn or ruptured ACL every year. These injuries often occur during athletic activities such as soccer, football, and skiing when one stops suddenly with the foot planted firmly on the ground. This action causes an over extension of the knee with the tibia moving too far forward on the femur. This stresses the ACL beyond its normal limits causing a tear of the ligament.
A physician can usually diagnose an ACL injury through a physical exam, although an MRI is often used to assist in the diagnosis.
If the tear is severe enough, an orthopedic surgeon may need to repair the ligament by performing arthroscopic knee surgery. By using a small camera and special instruments, the ACL can be replaced or repaired with special anchors guided by this surgical technique.
Guidelines for rehabilitation after ACL tear or repair will be made by the managing physician. However, common exercises after ACL injury and/or repair include:

