rabbits back legs not functioning

Question
We have had our rabbit almost 9 years and he is about 9+ years old.  He was a shelter bunny and looks like he came from a local golf course. He is neutered.  He has been very healthy for the most part although he had two episodes of not eating, drinking or pooping in the past two years from which he recovered.  We were on vacation for a week and had care for him.  When we returned, he was not using his hind legs and had to drag himself around his enclosure.  I see no trauma to his body and he does not mind being handled or moved. Any ideas on what might be ailing him?  We will not do any expensive procedures on him and want to know how to keep him as comfortable as possible.  Thank you.

Answer
This usually means a back injury. A rabbit kicking too hard with their back legs could break thier backs really easy. It also could be a kidney infection or an impaction of feces. I am not a vet, so i can not tell you 100% The best thing to do would be to take him to the vet and see what they say about him. If they want to do expensive procedures or stuff you cannot afford, then tell them that you just want to take him home and let him live out the rest of his life at home with out being proded and poked.
Samantha