What would you do??

Its suspected that Zorro has either a very bad bone infection, or bone cancer. He's getting tests done in two weeks to determine what it is. Right now the vets trying a different type of antibiotic, hoping that it will clear up the infection. If it is bone cancer, or if the bone infection is so bad that it has worn holes in the bone, the vet wants to amputate the leg to prevent it from spreading.
Here's my dilema. Zorro has a collapsed disk in his back, and therefor has back legs which are partially paralized. This makes walking a little more difficult for him since his back legs don't have much muscle, and have no stability. Its also a little painful.
I'm worried that if I amputate the leg(one of the front ones) his quality of life would be horrible since it would be even harder than it already is to walk. Right now he uses his front legs to support himself. I don't know what he would do if I took away one of them. I'm also worried that it would be more painful since he wouldn't be able to use his front legs to help out as much.
If you were in my situation, what would you do? Would you just let him live as long as possible until the infection was really bad, then put him down, or would you get the operation? I don't want him to be in constant pain. He's not even two years old yet and I hate to think of this, but I want to be prepared when the time comes so that if I have to make the decision, I'll have had plenty of time to think about it.
Your opinions are greatly appreciated.

TOugh call ... for you and Zorro ...

Wow that is really tough!
I think you need to weigh the benefits against the deficits like the effects to your kitty's quality of life. I do hope that the amputation is not necessary and that it is just an infection that the antibiotics can take care of.
With his back legs in such bad condition, I would also be worried about him getting around. If he was in great condition, losing one leg (I've heard) is something they can quickly adapt to.
I'm sorry you are in this position. It's heartbreaking to see our kitties sick. I think on this one if the vet is pushing for amputation I'd get a second vet opinion, maybe from a specialist.

Devlyn

I can't make your decision for you, it must be very difficult. Recently my neighbor's little dog got hit by a car and the dog is paralyzed in it's back legs. They would place her in the grass and the dog could do nothing but sit there. I thought what kind of life will that dog have. Now several weeks later the dog pulls itself around the back yard and appears happy to be alive, I underestimated it's desire to live. Of course this isn't exactly your situation but animals are survivors and if they are loved they will tolerate a lot, hopefully not a lot of pain.

Oh I am so sorry about this. I feel for you as we had to make the very decision to put our precious Marbles to sleep just two weeks ago. I couldn't make this decision for you but I know that we were faced with a hard decision of keeping him alive with hardly any quality of life or letting him be out of pain. I will just pray for you in this difficult time.

Thank you all so much for your replies. These past two years have been the hardest ever (Although also the most rewarding). Its just problem after problem with this little guy. He's actually started running around a little again(its more like a bunny hop though, lol) and his teeth are looking great for once. I hate having to think about this when he seems so healthy and happy to be alive.
When the vet suggested amputation(As a very very last resort he said) I don't think he thought much about the state of his back legs. I'll have to talk to him about it again.
I really hope this isn't the case though. Even if he has to be on antibiotics for months and months. I'd much rather that.