This is an article about The Active thyroid Hormone T3 and its role in the regeneration of peripheral nerves.

http://www.ncbi.nlm.nih.gov/pubmed/17402861

This could definitely be a treatment option for some people.

I developed peripheral neuropathy from long standing untreated hashimoto's thyroiditis and have been using primarily T3 with good success. I have finally begun to feel relief from these peripheral neuropathy symptoms. Return in muscle strength and size, less eye floaters, almost complete reduction in tingling in arms and legs as well as numbness and tingling in fingers.

If you have PN of any cause you could look into T3.