Based on the history you provided, below are possible causes for your kitten’s paralysis. If you still seek further information, please visit our Ask The Vet page to submit a one on one consultation with a licensed veterinarian 24 hours a day, 7 days a week.
Intervertebral disc injury
I rescued a kitten two days ago. He has deformed rear legs and has trouble knowing when he’s using the bathroom and needs helping having a bowel movement. He’s six weeks old. He eats well, plays and sleeps like a normal kitten. He even can drag his back end and chase my other cat. He’s very loving. I don’t want to euthanize him I just don’t know what to do from there. I need help. I work at a vet clinic and my doctor didn’t give me much information just said “wait and see”