I woke up this morning to find that my Pommeranium X who is about 9 years old is having problems walking on his hind legs. I rang the on-call vet as I was worried it was a tick. As we have no ticks in the area the vet advised that its probably a muscle issue. I'm still concerned as he can put slight weight on but slides/ falls over. He's in no visible pain & he's eating & toileting. I've looked up "slipped disc disease". Can anyone suggest anything I can do to test or help my pooch?

Wait for your regular vet to examine him. It could be something not very easy to find, however, such as a damaged nerve. Could he have been injured when you weren't watching?

My sister had a (younger) lab whose hind legs wouldn't work and she spent thousands, never getting a diagnosis. The problem finally resolved, but it wasn't clear why. It wasn't a disease carrying tick, it wasn't displasia, it wasn't visible on X rays, and the dog was healthy otherwise. Maybe a pinched nerve that unpinched, who knows.

You don't say how much regular exercise he gets, which if low can speed up old age arthritic symptoms. Get him a water bed but also keep him as active as possible. Don't feed him cheap dog food. If the vet finds nothing on exam and X-ray, massage him and maybe press a bit along his spine to check for a pain reaction. Move his legs while he's lying down to see if they can bend and lift without pain. Your vet of course may do this too, but if it's a nerve or nerves, finding it is almost impossible.