https://blogs.scientificamerican.com/observations/treating-chronic-pain-in-the-right-place-remotely/

An estimated 20.4 percent, or 50 million, Americans live with chronic pain, leading to nearly $560 billion each year in direct medical costs, lowering productivity and increasing disability. Today, chronic pain is one of the most common reasons for adults to seek medical care and has led to opioid dependence, anxiety, depression, restrictions in mobility and daily activities and overall reduction in quality of life. While short-term pain-relieving therapies provide relatively good solutions, an effective long-term solution for chronic pain has yet to be identified.

To establish what we are missing in chronic pain treatment, we first need to understand how the body perceives and responds to pain. Throughout the body we have pain-receptive neurons, known as nociceptors, which respond to damaging or potentially damaging stimuli by sending a “possible threat” signal. The signal travels through the nerves to the spinal cord, which processes the pain message and carries it up to the brain, where it is further processed by the thalamus and then sent to the cerebral cortex, where we perceive it.