Sorry to hear about your dog.
We had a Daschund and he needed a back surgery and had cataracts removed in his old age. Months and months of therapy helped he was very happy. He was not in pain any more but it was woth it. I know some people can't justify spending a lot of $$ on their pets but I would, it is part of your family. We had him for almost 3 years more. At the age of 14 we had him put to sleep for different complications that was not operable.