The article reads that piriformis syndrome can cause RSD-like symptoms from the compression of the sciatica...and the RSD symptoms are secondary to the primary cause, which is piriformis syndrome.

I had a terrible bout of piriformis syndrome diagnosed by my P.M. doc.
Iwent to my new chiro who had me lay on my stomach, and with all the pressure he could muster, pushed down on the piriformis and also another muscle that lies deeper called the obdurator (sp) I believe they are underneath the glutteous muscles..right where we sit!
He had just taken a special workshop where this muscle cluster was reviewed..
I felt relief over the next few days...he must have released a trigger point or a knot that was causing the nerve constriction.

This same chiro has also ordered a lumbar spine MRI which I will be scheduling soon...
I can't believe after all these years with really bad back/hip problems, none of my docs have ordered an MRI.
I like my new chiropractor!!!
Hope4thebest