What Are Anterior Cruciate Ligament (ACL) Injuries?

Anterior Cruciate Ligament (ACL) Injuries

Say: an-TEER-ee-ur KRU-shee-ate LIG-uh-ment IN-juh-rees

The ACL is one of four ligaments in your knee. It's behind your kneecap, keeping your knee stable and your shinbone from moving too far forward. An ACL injury happens when you tear this ligament and have trouble walking or playing sports.