Here is an article of a topical mix used in diabetic neuropathy where nothing else worked: painmuse.org/?p=274.

Aren't you on painkillers at night? I wonder if your team told you the Canadian Pain Society (CPS) found the meds you use only worked 23.7% of time. I presented a poster to the CPS 2 years ago finding that high dose B12 1000 ug every 1-2 days subcut has an analgesic effect and not only reduces pain 20% but augments gabapentin. If your pain is >7/10 you should be on marijuana or ketamine shots - another situation poorly known but the latter you can read about here:

http://www.anodyneheadachepain.com/Research/APS4.pdf