Hi. I can relate though I have seen multiple specialities and multiple opinions. Really unless they took my body apart I am diagnosticly tested out. They don't know why I have PN either. In addition though I have RSD which does make my limb feel dead cold and sends the pain very high. I think if you have not had another opinion yet you need one but also what other specialties have you seen? Have you had extensive bloodwork for things like auto immune? Hang in there