I think your neurologist is wrong. Back problems do cause foot/leg pain but never erythema, never. You are getting the run around and need to see a dermatologist preferably at a Medical center. I also have burning red toes, it is not neurological though many people with EM also have neuropathy it is not causal. The Cleveland Clinic site on neuropathy states it does not cause erythema however they do find a high correlation in people with these symptoms.
Sorry for the attitude i am just so fed up with the broken medical system we now have in this country.
Also if you read some of the Australian research on EM they are finding it much more common than stated here in the US. The reason its called rare seems to be that few doctors diagnosis it and most people with secondary EM just live with it. They give up after having the medical experience you describe in your post.
Looks like EM is not that rare.
Oh the burning pain can be from your back just not the redness.
Yeah, getting a Dr to diagnose EM is like pulling teeth because it’s so rare and they haven’t seen it before, but finally after many tests to rule out anything else causing my symptoms (2 and a half years) I got the diagnosis. It’s very frustrating, but be patient and persistent.