Have your Sciatic nerve looked into. I had a pretty bad bike crash (doored going 30mph, bounced on pavement with left hip). I would have burning sensations about the size of a fifty cent piece in my upper back, numb toes, etc. After 10+ years it finally subsided. Chronic pain is highly correlated with suicide. So best to get that fixed.

https://en.wikipedia.org/wiki/Sciatic_nerve