I have an older male with very little use of his back legs. He also can get flipped over when he tries to use them. He is mentally sound and sharp. You should post a picture. Can he curve his spine normally left to right? What are you temps. and what is your supplementation regime? Dragons can build up fibrous material around their spine, it shows on an x-ray on the outside but can build up on the inside as well restricting the nerves that control his back legs. What do you think is causing an impaction. When did he last go to the bathroom? I'm skeptical that it's an impaction if he is eating. Especially with an adult.
The dragon in the picture is Brutus. His spine is always curved as you see in the pics. Since he doesn't walk, his metabolism is very slow and he poops every 2 weeks or so. He's been here over 2 years now. He drags himself around pretty well though and seems very happy here.

