Many people kill or "put down" their precious dog because they are in pain and the vet's/dr.'s cannot figure out what is wrong with them. I have learned over the past 5 years (because it happened to my dog) that 9 times out of 10, if all tests come back "normal", take your dog directly to a Chiropractor because the dog is in significant pain in his back. Many dogs cannot walk and have severe weakness/paralysis in their legs due to pain, pinched nerved, ruptured disc. etc...