I also have had good results from cold therapy. I can no longer tolerate heat as it triggers my symptoms almost immediately. Even my Epsom Salts baths are no hotter then room temperature.

Since it is looking like my lumbar spine area is the source of symptoms (L4-5 & S1) that is where I place my gel product. Mine is by Elasto Gel. It wasn't inexpensive, but I have had it for over 10 years without a problem. It has velcro and I can attach it where I need it and it stays put. 10-15 minutes no more than 3 times a day is a big help. I also use it for prevention when I have overdone something before the burning begins.