I don't know if heat soothes him - but I have a lot of back pain and I find a hot water bottle really helps me. I also find that I sometimes have to sleep almost sitting up in bed - but thats because of a lesion sitting on my sciatic nerve -  I use v shaped pillows to support myself. I also find that lying in a big L shape helps sometimes too. I have been also known to sleep in a chair - beds are not always comfortable when your back and hips are sore. The most important thing is getting sleep, so how you find that comfort is really trial and error.