Persistent (chronic) pain is a widespread problem that affects around 8 million people of all ages in the UK (Chronic Pain Policy 2010). In 22% of cases, chronic pain leads to depression, and some
25% of those diagnosed with chronic pain go on to lose their jobs (Chronic Pain Policy 2010). In fact, around £3.8 billion a year is spent on incapacity benefit payments to those diagnosed with
chronic pain (Chronic Pain Policy 2010).
The International Association for the Study of Pain has defined pain "as an unpleasant sensory or emotional experience resulting from actual or potential tissue damageâ€¦". Chronic pain may be defined as pain that lasts beyond the usual course of the acute disease or expected time of healing, and it may continue indefinitely.
Typical chronic pain conditions include: osteoarthritis; rheumatoid arthritis; low back, shoulder and neck pain; headache and migraine; cancer pain; fibromyalgia; neuropathic pain (e.g. sciatica, trigeminal neuralgia, post herpetic neuralgia); chronic overuse conditions (e.g. tendonitis); and chronic visceral pain (e.g. irritable bowel syndrome, interstitial cystitis, endometriosis) (Singh 2010).
Chronic Pain Policy Coalition, 2010. About chronic pain [online]. Available:
2010 [online]. Available: http://emedicine.medscape.com/article/310834-overview
How acupuncture can help
An early systematic review of acupuncture for chronic pain found very limited evidence to support it (Ezzo 2000), but numerous large, well conducted studies in the last 10 years have substantially changed the picture. Recent reviews have shown that it is more effective than no treatment or usual care for chronic back pain, osteoarthritis, or headache (Sherman 2009). There is also evidence that it is more effective than sham acupuncture for chronic knee pain or headache and, at least in the short term, for chronic back pain (Hopton 2010). Other conditions have been less well researched.
For more details of specific research on chronic pain conditions see our other Factsheets: Acupuncture and Back Pain; Acupuncture and Endometriosis; Acupuncture and Frozen Shoulder; Acupuncture and IBS; Acupuncture and GI Tract; Acupuncture and Migraine; Acupuncture and Headache; Acupuncture and Sciatica; Acupuncture and Fibromyalgia; Acupuncture and Osteoarthritis; Acupuncture and Rheumatoid Arthritis; Acupuncture and Dysmenorrhoea; Acupuncture and Neck Pain. There is also evidence from randomised controlled trials and systematic reviews that suggests acupuncture may reduce chronic pain in myofascial syndrome (Shen 2009), chronic shoulder problems (Lathia 2009), chronic prostatitis/chronic pelvic pain syndrome (Lee 2009) and tennis elbow (Trihn 2004). There is preliminary evidence for ear acupuncture in cancer pain (Lee 2005).
In general, acupuncture is believed to stimulate the nervous system and cause the release of neurochemical messenger molecules. The resulting biochemical changes influence the body's homeostatic mechanisms, thus promoting physical and emotional well-being. Stimulation of certain acupuncture points has been shown to affect areas of the brain that are known to reduce sensitivity to pain and stress, as well as promoting relaxation and deactivating the 'analytical' brain, which is responsible for anxiety (Wu 1999).
Acupuncture may help relieve chronic pain by:stimulating nerves located in muscles and other tissues, which leads to release of endorphins and other neurohumoral factors (e.g. neuropeptide Y, serotonin), and changes the processing of pain in the brain and spinal cord (Pomeranz 1987, Han 2004, Zhao 2008, Zhou 2008, Lee 2009, Cheng 2009);
- stimulating nerves located in muscles and other tissues, which leads to release of endorphins and other neurohumoral factors (e.g. neuropeptide Y, serotonin), and changes the processing of pain in the brain and spinal cord (Pomeranz 1987, Han 2004, Zhao 2008, Zhou 2008, Lee 2009, Cheng 2009);
- increasing the release of adenosine, which has antinociceptive properties (Goldman 2010);
- modulating the limbic-paralimbic-neocortical network (Hui 2009);
- reducing inflammation, by promoting release of vascular and immunomodulatory factors (Kavoussi 2007, Zijlstra 2003);
- improving muscle stiffness and joint mobility by increasing local microcirculation (Komori 2009), which aids dispersal of swelling.