This condition occurs when the anterior cruciate ligament (ACL), the band of tissue that connects the femur to the tibia inside the knee joint, becomes torn or worn away, causing pain and instability of the knee.



An ACL tear is typically caused by a severe injury or trauma to the knee, often during athletic activities. A sudden stopping and twisting motion of the knee, or a blow to the knee that forces the joint to bend beyond its normal range of motion may cause the ACL to stretch and tear.


The most common symptom of a torn ACL is pain in the knee. Other symptoms may include immediate weakness or a popping sound in the knee, swelling, stiffness, and bruising. Walking is painful and the knee may feel unstable.


Treatment options for torn ACL include rest, cold compress, wrapping the knee, elevating the knee, physical therapy and anti-inflammatory medications. Surgery is commonly required.