Hi, well the vet thinks it's either arthritis or a neurological problem. Skittle's been prescribed an anti-inflammatory (Metacam for cats) at a very small dose for 4-5 days (we're to stop giving it on day 5 whether it works or not) but hopefully will see an improvement in a couple of days if it is arthritis.
If after day 5 there's no improvement then we're to go back to the vet for an x-ray to see if there's any compression in his back/spine area. If that's proved positive then I have no idea what will happen to be honest. As the vet said, they are so tiny and have such a short lifespan (it may be just kinder to let him live it out I suppose providing he's happy and healthy in all other aspects until he is in evident pain maybe is what she was getting at?).
But fingers crossed the Metacam will work.
In time we may have to alter his cage set up as Cypher has indirectly suggested but I did mention that to the vet but she said that while he's coping with his tunnels just leave him for now basically quality of life; he's enjoying himself so leave him be. No more hamster balls though I think, which is fine by us as he can't escape into the walls or anything - we're lucky that the lounge/dining room is hamster proof!
He didn't bite the vet either, which was nice!
Thanks for the suggestion on the oil as well Cypher
and yes, she said if he won't take the Metacam from the bottle I can put it on food.