I don't know the ages of my older dragons. They were all nameless rescues. I do have one that cannot use his back legs. He has a build up of fibrous material around his spine that has fused it in a curved position. I have no idea what his age is but he has been here since 9/1/07. He can move his back legs and can almost walk in the bath, but, otherwise he drags himself in his tile enclosure.
Reduced use of hind legs is also a sign of advanced MBD. It can also be the result of impaction or a tumor putting pressure on the spine. My suggestion is to have him x-rayed. You will be able to tell if it is MBD or a condition similar to the one mine hasd or at least you will be able to narrow out some of the possibilities.
