My father has had chronic pain in his side for 10 years: what to do?

First of all, I wanted to thank you for your concern and sensitivity in making your knowledge available to users. I am looking for a natural treatment for the treatment of neuropathic pain, that is from the involvement of a nerve root with abdominal projection. My father has a pain in the form of burning, particularly in his right side; in his side he has been in pain for about 10 years, the pains are unbearable. He describes them as an open wound. To the touch the abdomen is palpable, pressing deeply on the side in question feels pain, even when he moves he starts to jump. His conviction leads him to ask if there is a specific exam that detects the problem in that specific part of the body. He moves, gets up by himself, does his things … even if he lately finds rest by lying down.