I have dealt with a similar issue for awhile now. I was lucky enough to never experience back pain or issues until I turned 38. Then out of nowhere I not only felt pain, I lost quite a bit of flexibility and mobility. Doctors offered pain meds and said it was muscular. I refused the pain meds and sought other advice.
Eventually I found a chiropractor who also took X-rays and video scans from the front, back and side view. He said I was perfect for my age as far as back and spine, but that my right hip was so far out of whack it was causing major issues with my lower back.
I got about 2 adjustments per week for 3 weeks. I slowly regained my flexibility and mobility and by the 3rd week zero pain at all. It was so awesome to feel pain I had dealt with for a whole year disappear.
I still have to go and get adjustments from time to time. Usually about once every 2-3 months. I can feel when I need the adjustment because the flexibility and mobility begins to tighten up rapidly when my hip begins to slip. Luckily this process has helped my issue and is affordable.
I would definitely at least see a chiro if you have the resources to do so. It is an awful feeling when you cannot do what you love due to pain and mobility issues, but it's even worse when it spills over into your day to day routine. Also, remember not all chiro do physical adjustments and take X-rays and video. My first chiro only used the little hammer gun and didn't catch my hip out of place without the X-ray and video. So keep that in mind when betting who you want to see.
Good luck and if this helps let us know how your treatment goes!
RE: Practicing Jiujitsu with chronic backpain