Pain very low back/hips, tingles down legs to ankles. Pelvis feels out of place. Mri discs ok. Had si inject, pt, lumbar denervation. Dr out of idea?

One diagnosis. That can present sciatic symptoms with normal lumbar discs is pyriformis syndrome whereby the pyriformis muscle impinges on the sciatic nerve. This is a somewhat controversial and difficult diagnosis to make but might be something to discuss with your doctor. Mr neurography can sometimes help make the diagnosis.