According to National Institute of health (NIH), results from a number of studies suggest that acupuncture may help ease types of pain that are often chronic such as low-back pain, neck pain, and osteoarthritis/knee pain. It also may help reduce the frequency of tension headaches and prevent migraine headaches. Therefore, acupuncture appears to be a reasonable option for people with chronic pain to consider.
The mechanism of action of how acupuncture works in pain management is interesting, it seems the stimulation of specific sites on the body surface (Acupoints) exerts a marked inhibitory influence on pain. The acupoints have been known to the Chinese for many years. Their validity in pain control has been verified by numerous researchers.
One experimentally well-documented mechanism for pain relief by acupuncture is the modulation of endorphin levels. Myofascial pain is relieved primarily by inactivating the source of pain. Acupuncture apparently alleviates the awareness of pain.
For more information visit : https://nccih.nih.gov/health/acupuncture/introduction#hed3