The missus took him while I was at work, she said the felt down his spine till the found like a knotch or tight spot, lifted his back legs off the ground and applied pressure on his back and he yelp and shied alot of discomfort, I also think I may no what caused it, yesterday I noticed when he walks in and out of his cage he catches the last part of his back and he was arching to get in, so out cane the hacksaw and took about 2 inches off it so now it's not a problem.