>>Back sleeping causes me to have low back pain.
Side sleeper here. Back sleeping causes me to wake up and roll onto a side :-) I can't stay asleep on my back.
I spent almost a month bedridden in a SICU (brain infection I've mentioned before). I normally alternate sides, but all the tubes attached to me meant it was back or left side. Had a frozen left shoulder by the time I was in rehab (relearning walking, etc.)
BTW/FWIW, the hospital I was in had amazingly comfy mattresses - but they had me on one specifically to prevent bed sores. If you're in the hospital for more than one night it's IMO worth it to advocate for one of those. I got lucky: my neurosurgery team did that, but if you - or a loved one- is a side sleeper stuck and in the hospital it might be worth asking.
Also: I mostly slept, but when I was awake I'd read fiction or watch hospital shows. When my wife asked me why those shows, I realized it was because the patents in those shows were so much worse off than me - so it helped me keep perspective - and do my *one* job, which was to not die. :-)