Anterior Cruciate Ligament Knee Injuries
Jennifer Evans, Jeffery l. Nielson
Abstract
The anterior cruciate ligament (ACL) is one of 2 cruciate ligaments that aids in stabilizing the knee joint. It is a strong band made of connective tissue and collagenous fibers that originate from the anteromedial aspect of the intercondylar region of the tibial plateau and extends posteromedially to attach to the lateral femoral condyle. The anteromedial bundle and posterolateral bundle form the 2 components of the ACL. The ACL and the posterior cruciate ligament (PCL) together form a cross (or an “x”) within the knee and prevent excessive forward or backward motion of the tibia relative to the femur during flexion and extension. The ACL additionally provides rotational stability to the knee with varus or valgus stress. ACL sprains and tears are common knee injuries, with a reported incidence of 100,000 to 200,000 in the United States every year.