Anterior Cruciate Ligament Tear
(ACL Tear)

The ACL is a ligament that runs in the center of the knee at a diagonal that aids in knee stability with rotational motion. It prevents the tibia from sliding forward on the femur. Injury is most common in those who play sports such as soccer, football, and basketball.

Causes & Symptoms

Cause of an ACL injury include rapid change in direction, sudden stopping, landing incorrectly, and direct collision. Typical symptoms include a “pop” sound at time of injury with immediate knee swelling. Over a few hours the knee may feel unstable and range of motion with be decreased.

Evaluation & Treatment

Initial evaluation includes a medical history, physical examination, and x-rays to rule out other associated conditions. Specialized examination maneuvers to test the integrity of the ACL and other structures in the knee may be done. An MRI is indicated in those where there is a suspicion for an ACL tear.

Treatment of ACL tears is dependent on age, activity level, and desire to return to activity. ACL tears do not heal though nonsurgical treatment may be indicated in those without knee instability or who are interested in activity modification and possibly bracing. For those who desire return to previous activity level, surgical treatment is recommended. This is done arthroscopically as an outpatient and several options exist in regards to graft. Regardless of treatment, rehabilitation plays a critical role. A physical therapy program will help regain knee strength and motion and typically lasts until the knee is equal to the other side.