HI I m Dr Steve. I am sorry to hear about Taff's problems. WIth torn ligaments, it can take weeks or even a few months for ligaments to heal. IF it is the anterior cruciate ligament in the knee, it may require surgery to completely heal. The Rimadyll is an antiinflammatory and pain medicine that helps to make him feel better and to promote healing, but if the ligament is torn or stretched severely, it will still take time to heal. In some cases, giving the rimadyl will make a dog feel good enough to walk on the leg which may continue to stretch or move the ligament enough to prevent healing. WIth that said, it is still necessary t have some pain relief and antiinflammatory activity for healing. THis means that if the rimadyl was helping him feel better, that is good, but you may need to severely restrict his exercise to a very small kennel or cage so he doesn't continue to reiinjure the leg. If the Rimadyl is causing problems, there are other antiinflammatory medicines that your vet can try like Deramaxx, Metacam or Etogesic. In some cases when the side effects of one medicine are not tolerable, there usually another one that will work. You should ask your vet about restricting exercise or even possibly putting the leg in a cast to immobilize the ligament and prevent more stretching or damage from walking. WIthout examining Taff, it is hard for me to say for sure that this will work in his case, but would be worth discussing with your vet, I hope this has helped. I will check back later to see if you have more questions. Thanks for your question and good luck.