@andilynn, my experience may not be pertinent to yours, but I thought it might, so here goes. I had lower back pain for several months, and I was examined by spine specialists, imaged out by MRI, and had physical therapy for weeks. To no avail. Back to my Internist for a talk. She speculated that I may have an inflammation in one of my sacroiliac joints, where the lower end of my spine connected to my pelvis. "How can we find out?" I asked. "There was nothing on the MRI to suggest it."

"Sacroiliac inflammation isn't diagnosed or confirmed with Xrays, CT scans, or MRIs," she said. "We'll have to inject an inflammatory medication directly into the sore joint and see if that takes care of it." So we did, and it did. And it's been three years now since I had a lower back pain. I had inflammation of one sacroiliac joint, confirmed when it went away after direct injection of an anti-inflammatory medication (the identity of which I don't know). Even so, talk it over with your doctor and, if that proves fruitless, get a second opinion from another qualified medical professional.