I have used capsaicin on my scar. It defunctionalizes vanilloid receptors in small fiber nerves preventing them from sending pain signals. Over time some of the defunctionalized receptors retract from the dermis and new receptors form over a period of weeks to months. I wonder sometimes if that might mean you can get new ones that act right! There are actually some decent studies on the use of capsaicin for pain and there is currently a high power 8% capsaicin pain patch called Quetenza that must be used in a doctor's office. It has been used with CRPS and diabetic neuropathy patients per literature. Forgive me if I explained poorly or got something wrong, it has been a while since I read those studies.