Because of its anatomical attachments this ligaments primary function is to prevent the
lower or Tibial side of the joint from slipping forward on the upper or Femoral side of the
joint (See illustration below). The Stifle or knee joint is only meant to rotate like a hinge.
The Tibia is not meant to shift forward on the Femur.
The most common injury by far is the Anterior or Cranial Cruciate injury. It is the most
common orthopedic injury in dogs. Approximately 1.5 billion dollars a year is spent on
treating this injury.