Our Husky, Yeti, tore her cranial cruciate ligament (like a humans Anterior cruciate ligament or ACL). Interestingly, unlike humans who really don't use the ligament unless the joint is overextended, a dogs ligament is used full time to keep the femur from slipping backward on the tibia plateau. Thus, repairing the ligament is almost futile since it will likely tear again.
There is a proceedure that seems kinda radical
called Tibial Plateau Leveling Osteotomy or TPLO. In this proceedure the tibia is cut and rotated so that the femur sets level and doesn't need the ligament. It's an interesting proceedure and requires a long recovery time but the dog is suppose to be able to walk and run normally afterward.
