What is an ACL? The ACL is the Anterior Cruciate Ligament, or one of two crossing ligaments in the middle of the knee. Basically, the ligaments are soft tissue bands that stabilize the knee. The function of the ACL is to prevent the tibia from moving too far forward on the femur.
What is an ACL tear? ACL tears are one of the more common knee injuries that people are aware of given that (relatively) high numbers of these injuries happen in professional and recreational sports. Most likely, you or someone you know has had an ACL injury. ACL tears commonly happen with cutting, pivoting, and jumping sports such as soccer, basketball, football, lacrosse, and volleyball.