@Murrmurr I'm sorry to hear about your back pain issues.
I had a fall some years ago, head over heels down some stairs, fractured two fingers on one hand, thumb and wrist on the other, did some damage to an ankle. Back was literally black and blue for weeks and only ached during that time - the pain kicked in later and never left. Doctor just keeps prescribing pills but they don't work, nor do over-the-counter painkillers. I've never had proper investigations and unlikely now with the way things are here in our health care system these days, so I live with chronic pain and restricted mobility it causes.
Your experience(s) sound dreadful and I hope
@Moon Rat's recommendation offers/provides a solution for you.