Just wondering what your doctor thinks the underlying problem is. 4 years is a long time to suffer chronic pain. My first question to him would be 'what is left to rule out'?

If you've been to the same doctor for this amount of time and he can't find out what's the root of the problem--1)how does he know how to treat the problem? And 2) maybe it's time for another doctors opinion.

For chronic pain, Fentanyl patches are often used with a supplemental analgesic when you have an exacerbation.

Does any "Medicinal" smoke help?

Hope this helps out a little. Wish you luck in finding a good doc that can connect the dots.