What is the CCL?
The cranial cruciate ligament (known as the anterior cruciate ligament, or ACL, in humans) is one of several ligaments in the stifle (knee) that connect the femur (thigh bone) to the tibia (shin bone). The CCL has 3 main functions: (1) prevent cranial displacement of the tibia in relation to the femur (cranial drawer sign) (2) prevent hyperextension of the knee, and (3) prevent internal rotation of the tibia.