In most cases, you’ll know your dog has sustained a ruptured CCL due to knee area being swollen, or you notice your dog in sudden pain, weakness, or instability in the hind limb or knee cap area.
However, the key diagnosis is the presence of a type of knee instability called cranial drawer sign. This occurs when the tibia moves forward when touching the femur like in the motion of a drawer being opened. This extremely painful testing is best performed when the dog is under anesthesia, allowing for the knee to totally relax.
In serious conditions, radiographs, MRI, and arthroscopic surgery are helpful diagnostics tools that are used diagnose knee injuries.