I also have a lot of muscles spasm in my thoracic spine and have trouble
breathing and heaviness too. I can understand and it's very painful and makes you fatigued. I have a bulging disk at T11-12 but the Dr. said they
usually don't do surgery in the thoracic unless it was critical. Yesterday,
the Dr. gave me Lidoderm patches to try on my thoracic back. I didn't try it yet b/c I have a rash and that needs to clear up first. It's suppose to relax the muscles spasms. Medication I've tried doesn't seem to help. Do you find if you lay on the floor to stretch, those muscles go into spasms even more until they relax some and takes your breathe away? That's how it is with me and it also cracks like crazy. I hope you can find relief soon!