I am having terrible back issues. My muscles seem to seize up from the middle of my back to lower back.

At first I blamed it on my low back fusion (Si-L5). Then I chalked it up to the lack of muscle tone, but I have been back to "gym" exercising for a few weeks now. Even at the gym it seizes up. I can't get the problem to go away or even dissipate.

If I sit for a bit it seems to ease up. But even then, returning to sweeping, doing laundry, etc. it returns within a few minutes.

Could this be dystonia in my back?

I can't walk very far without support; e.g. cane, walking stick. Even then I the muscles seize on me. It is painful and is dragging me down