Hi there,
Sorry you're having such a hard time, you have definitely come to the right place for help and support. I've had sacroiliitis for 13 years diagnosed with crohns last december. I find that heat is the best thing for soothing my SI joint and my sore tum, I use the heat things you microwave, before that I used to walk around with a hot water bottle down the back of my trousers, it really worked a treat. I know its not the answer to everything but i do find that when I've had all the pain relief I'm allowed that the warmth does wonders. Good luck with the surgery, take care and keep in touch. :hug: