Anterior cruciate ligament

The anterior cruciate ligament (or ACL) is one of the four major ligaments of the knee.

It connects from a posterio-lateral part of the femur to an anterio-medial part of the tibia. These attachments allow it to resist anterior translation of the tibia, in relation to the femur. More specifically, it is attached to the depression in front of the intercondyloid eminence of the tibia, being blended with the anterior extremity of the lateral meniscus.

It passes up, backward, and laterally, and is fixed into the medial and back part of the lateral condyle of the femur.

Injury
Although there are many ACL injuries, the ACL is next to the most commonly injured knee ligament, the posterior cruciate ligament (PCL) and commonly injured by athletes. The ACL is often torn during sudden dislocation, tortion, or hyperextension of the knee. It is a very common injury in football, hockey, skiing, skating and basketball, due to the enormous amount of pressure, weight and number of blows the knee must withstand.

Diagnosis

The Lachman test is supported by most authorities to be the most reliable and sensitive maneuver for the diagnosis of an ACL tear.