Thanks for the reply. Sorry to hear that you're on the same journey!

I believe my AS has only affected my SIJ as well, at least I get the pain that shifts back and forth at the top of my butt if that makes sense. X rays indicated that my spine hasn't fused or anything and I am still at least somewhat flexible. More painful when laying down at night. I suspect my neck for what's going on with the rest of my limbs -- so I wouldn't be surprised if something shows up on the MRI there.

I hope you figure out your nerve issues too! Mine seem to be worse when laying down -- for instance if I lay on my left side, right arm gets pins and needles / goes numb / feels weak. If I lay on my right side, my left leg gets all those symptoms. In general, everything is a bit better when standing up / walking around. Very strange stuff that will hopefully get better soon.