How does an anesthesiologist with a fellowship in pain management differ from a physiatrist?

One is rehab: the anesthesiologist has 3 years of training on epidurals, spinals nerve blocks etc and maybe a 1-2 year fellowship for pain mgmt., The physiatrist starts as a rehab doctor and adds epidurals to their training some blocks as well. Its likely better to see a board certified anesth for pain mgmt. but a well trained physiatrist can handle most situations as well