James, similar but different. I had lower back pain for years. Finally I decided to do something about it. The procedure, same as yous but different place, is called a radiofrequency ablation. Since I had pain on both sides of my back I had the anesthetic injections done on different days and then the ablations done on different days. Four visits to the surgery center. They burn out the specific nerves that are sending the pain signals to the brain. The nerves will eventually grow back. Both of my ablations were a success and I've had little to no back pain in the last 3 months. Don't know how long it will last but, if the pain returns, they can do that procedure again. That's on the good side and I hope that's the way it turns out for you.
Unfortunately, for me, shortly after I had that procedure my Sciatic nerve decided that it should take over producing pain going from my left butt down my leg into my foot. I've had 3 injections, each one more localized trying to stop the pain. The last one did, for 24 hours, until the anesthetic wore off and the pain came back with a vengeance. That, at least, identified where the pain was coming from. I'm now trying to find a neurosurgeon to correct the problem. Again, unfortunately, specialists are booked up months in advance.
One of my problems with all of this is my shop time has been severely limited. Most days, no time at all, other days an hour or two with periods of having to sit down. With the holidays upon us I wasn't able to make some of the gifts that I intended to. Will have to buy some junk instead. Oh, well, Merry Christmas to all of you who persevered to read this. And Merry Christmas to those of you who didn't.