The anterior cruciate ligament (ACL) is a cruciate ligament which is one of the four major ligaments of the human knee. In the quadruped stifle (analogous to the knee), based on its anatomical position, it is referred to as the cranial cruciate ligament.
The ACL originates from deep within the notch of the distal femur. Its proximal fibers fan out along the medial wall of the lateral femoral condyle. There are two bundles of the ACL—the anteromedial and the posterolateral, named according to where the bundles insert into the tibial plateau. The ACL attaches in front of the intercondyloid eminence of the tibia, being blended with the anterior horn of the lateral meniscus. These attachments allow it to resist anterior translation of the tibia, in relation to the femur.