I'm an expert on this, because I had Piriformis Syndrome before it was a recognized condition.
Most doctors are MDs, and many of them do not believe in this. Plus, the condition can be confused with, or concurrant with, a disc problem at L5-S1. But the kind of doctors called Osteopaths, or DOs, are more likely to know how to treat the piriformis, because the first article on the syndrome was written by a DO, and published in their journal.
But what you really need to do is to seek out a doctor of Applied Kinesiology. It would be a violation of site rules to give you a link. Google "International College of Applied Kinesiology". On their website, you will find a link to find AK doctors in your area. They will know how to shut down the spasms of the piriformis muscle that are impinging on your sciatic nerve, and if there is a spinal issue that is involved, they will know how to fix that too.
