Acupuncture (Chinese: 針灸, Pinyin: zhēn jiǔ) is a broad term covering techniques for inserting and manipulating thin needles into "acupuncture points" on the body in order to restore health and well-being. In the West, it is associated with Traditional Chinese medicine, or TCM along with herbal medicine and tui na. Other types of acupuncture, notably Japanese, Korean, and classical Chinese acupuncture, are practiced and taught throughout the world. The mechanism of acupuncture and its effectiveness are a matter of active scientific research and debate.

Brief History

Acupuncture originated in China then spread into Asia, spawning a variety of techniques, treatment styles, and theoretical frameworks.

In China, the practice of can perhaps be traced as far back as the 1st millennium BCE and archeological evidence has been identified with the period of the Han dynasty (from 202 BCE to 220 CE). Forms of it are also described in the literature of traditional Korean medicine where it is called chimsul. It is also important in Kampo, the traditional medicine system of Japan.

Recent examinations of ÷tzi, a 5000-year-old mummy found in the Alps, have identified over fifty tattoos on his body, some of which are located on acupuncture points that would today be used to treat ailments ÷tzi suffered from. Some scientists believe that this is evidence that practices similar to acupuncture were practiced elsewhere in Eurasia during the early bronze age[1], [2].

Acupuncture's origins in China are uncertain. The earliest Chinese medical texts (Ma-wang-tui graves 68 BCE) do not mention acupuncture. The Chinese medical text that first describes acupuncture is The Yellow Emperorís Classic of Internal Medicine (History of Acupuncture), which was compiled around 305- 204 BCE Some hieroglyphics have been found dating back to 1000 BCE that may indicate an early use of acupuncture. Bian stones, sharp pointed stones used to treat diseases in ancient times, have also been discovered in ruins (History of Acupuncture in China); some scholars believe that the bloodletting for which these stones were likely used presages certain acupuncture techniques [3].

RC Crozier in the book Traditional medicine in modern China (Harvard University Press, Cambridge, 1968) says the early Chinese Communist Party expressed considerable antipathy towards TCM, ridiculing it as superstitious, irrational and backward, and claiming that it conflicted with the Partyís dedication to science as the way of progress. Acupuncture was included in this criticism. Reversing this position, Communist Party Chairman Mao later said that "Chinese medicine and pharmacology are a great treasure house and efforts should be made to explore them and raise them to a higher level"[4]. Barefoot doctors were trained to provide inexpensive health care in rural Chinese communities. After the Cultural Revolution, TCM instruction was incorporated into university medical curricula under the "Three Roads" policy, wherein TCM, biomedicine and a synthesis of the two would all be encouraged and permitted to develop.

Traditional Theory

TCM is based on a different paradigm than scientific biomedicine. Acupuncture treats the human body as a whole that involves several "systems of function" that are in many cases associated with (but not identified on a one-to-one basis with) physical organs. Some systems of function, such as the "triple heater" (San Jiao, also called the "triple burner") have no corresponding physical organ. Disease is understood as a loss of homeostasis among the several systems of function, and treatment of disease is attempted by modifying the activity of one or more systems of function through the activity of needles, pressure, heat, etc. on sensitive parts of the body of small volume traditionally called "acupuncture points" in English, or "xue" (穴, cavities) in Chinese. This is referred to as treating "patterns of disharmony".

Treatment of acupuncture points may be performed along the twelve main or eight extra meridians, located throughout the body. Of the eight extra meridians, only two have acupuncture points of their own. The other six meridians are "activated" by using a master and couple point technique which involves needling the acupuncture points located on the twelve main meridians that correspond to the particular extra meridian. Ten of the main meridians are named after organs of the body (Heart, Liver, etc.), and the other two are named after so called body functions (Heart Protector or Pericardium, and San Jiao). The two most important of the eight "extra" meridians are situated on the midline of the anterior and posterior aspects of the trunk and head. The twelve primary meridians run vertically, bilaterally, and symmetrically and every channel corresponds to and connects internally with one of the twelve Zang Fu ("organs"). This means that there are six yin and six yang channels. There are three yin and three yang channels on each arm, and three yin and three yang on each leg.

The three yin channels of the hand (Lung, Pericardium, and Heart) begin on the chest and travel along the inner surface (mostly the anterior portion) of the arm to the hand.

The three yang channels of the hand (Large intestine, San Jiao, and Small intestine) begin on the hand and travel along the outer surface (mostly the posterior portion) of the arm to the head.

The three yang channels of the foot (Stomach, Gallbladder, and Bladder) begin on the face, in the region of the eye, and travels down the body and along the outer surface (mostly the anterior and lateral portion) of the leg to the foot.

The three yin channels of the foot (Spleen, Liver, and Kidney) begin on the foot and travel along the inner surface (mostly posterior and medial portion) of the leg to the chest or flank.

The movement of qi through each of the twelve channels is comprised of an internal and an external pathway. The external pathway is what is normally shown on an acupuncture chart and it is relatively superficial. All the acupuncture points of a channel lie on its external pathway. The internal pathways are the deep course of the channel where it enters the body cavities and related Zang-Fu organs. The superficial pathways of the twelve channels describe three complete circuits of the body.

The distribution of qi through the meridians is said to be as follows: Lung channel of hand taiyin to Large Intestine channel of hand yangming to Stomach channel of foot yangming to Spleen channel of foot taiyin to Heart channel of hand shaoyin to Small Intestine channel of hand taiyang to Bladder channel of foot taiyang to Kidney channel of foot shaoyin to Pericardium channel of hand jueyin to San Jiao channel of hand shaoyang to Gallbladder channel of foot shaoyang to Liver channel of foot jueyin then back to the Lung channel of hand taiyin

Traditional Chinese medical theory holds that acupuncture works by normalizing the balance of qi "vital energy" throughout the body. Pain or illnesses are treated by attempting to remedy local or systemic accumulations or deficiencies of qi. Pain is considered to indicate blockage or stagnation of the flow of qi, and an axiom of the medical literature of acupuncture is "no pain, no blockage; no blockage, no pain".

Many patients claim to experience the sensations of stimulus known in Chinese as "deqi" (得氣 "obtaining the qi"). This kind of sensation was historically considered to be evidence of effectively locating the desired point. There are some electronic devices now available which will make a noise when what they have been programmed to describe as the "correct" acupuncture point is pressed.

The acupuncturist will decide which points to treat by thoroughly questioning the patient, and utilizing the diagnostic skills of traditional Chinese medicine which include observation of the left and right radial pulses at three levels of imposed pressure and analysis of the tongue coating, color and the absence or presence of teeth marks around the edge.

There are also theories being developed to explain effects observed for acupuncture within the orthodox Western medical paradigm.

Because the theories of TCM are not based on science, TCM has been called pseudoscience. Ted Kaptchuk, author of the popular introductory text "The Web That Has No Weaver", refers to TCM's conceptual framework as "prescientific" (1983).

According to the NIH consensus statement on acupuncture [5]:

"Despite considerable efforts to understand the anatomy and physiology of the "acupuncture points", the definition and characterization of these points remains controversial. Even more elusive is the basis of some of the key traditional Eastern medical concepts such as the circulation of Qi, the meridian system, and the five phases theory, which are difficult to reconcile with contemporary biomedical information but continue to play an important role in the evaluation of patients and the formulation of treatment in acupuncture."

Categories of Acupuncture Points

Certain acupuncture points are ascribed different functions according to different systems within the TCM framework.

Perspective on Treatment of Biomedical Disease

Although TCM is based on the treatment of "patterns of disharmony" rather than biomedical diagnoses, practitioners familiar with both systems have commented on relationships between the two. A given TCM pattern of disharmony may be reflected in a certain range of biomedical diagnoses: thus, the pattern called Deficiency of Spleen Qi could manifest as chronic fatigue, diarrhea or uterine prolapse. Likewise, a population of patients with a given biomedical diagnosis may have varying TCM patterns. These observations are encapsulated in the TCM aphorism "One disease, many patterns; one pattern, many diseases". (Kaptchuk, 1982)

In 1979, an interregional seminar in Beijing sponsored by World Health Organization drew up the following provisional list of diseases that lend themselves to acupuncture treatment. The compilers of the list stated that "the list is based on clinical experience, and not necessarily on controlled clinical research: furthermore, the inclusion of specific diseases are not meant to indicate the extent of acupuncture's efficacy in treating them" [6].

This list is based on TCM and not on science. Since 1979, large, randomized controlled studies have for the most part failed to demonstrate acupuncture's efficacy for these conditions. Thus, this list is not a scientific endorsement of efficacy, but rather reflects of the clinical experience of TCM practitioners. These indications are still taught in TCM curricula in China, the United States, Great Britain and elsewhere. Classically, "in clinical practice, acupuncture treatment is typically highly-individualized and based on philosophical constructs, and subjective and intuitive impressions" and not on controlled scientific research [7].

Legal and Political Status

In the USA, acupuncture is practiced by a variety of healthcare providers. Practitioners who specialize in acupuncture and TCM are usually referred to as "licensed acupuncturists", or L.Ac.'s. Other healthcare providers such as physicians, dentists and chiropractors sometimes also practice acupuncture. L.Ac's generally receive from 2500 to 4000 hours of training in TCM theory, acupuncture, basic biosciences, and sometimes Chinese herbology and/or bodywork. The amount of training required for healthcare providers who are not L.Ac.'s varies from none to a few hundred hours, and in Hawaii the practice of acupuncture requires full training as a licensed acupuncturist. The National Certification Commission for Acupuncture and Oriental Medicine tests practitioners to ensure they are knowledgeable about Chinese medicine and appropriate sterile technique. Many states require this test for licensing, but each state has its own laws and requirements. In some states, acupuncturists are required to work with an M.D. in a subservient relationship, even if the M.D. has no training in acupuncture.

Acupuncture is becoming accepted by the general public and by doctors. Over fifteen million Americans in 1994 tried acupuncture. A poll of American doctors in 2005 showed that 60% believe acupuncture was at least somewhat effective, with the percentage increasing to 75% if acupuncture is considered as a complement to conventional treatment [8].

In Australia, the legalities of practicing acupuncture also vary by state. In 2000, an independent government agency was established to oversee the practice of Chinese Herbal Medicine and Acupuncture in the state of Victoria. The Chinese Medicine Registration Board of Victoria [9] aims to protect the public, ensuring that only appropriately experienced or qualified practitioners are registered to practice Chinese Medicine. The legislation put in place stipulates that only practitioners who are state registered may use the following titles: Acupuncture, Chinese Medicine, Chinese Herbal Medicine, Registered Acupuncturist, Registered Chinese Medicine Practitioner, and Registered Chinese Herbal Medicine Practitioner.

In the United Kingdom, British Acupuncture Council (BAcC) members observe the Code of Safe Practice with standards of hygiene and sterilization of equipment. Members use single-use pre-sterilized disposable needles. Similar standards apply in most jurisdictions in the United States and Australia.

In Ontario, Canada bill #50 defines "Traditional Chinese Medicine" (TCM) and includes standards for accreditation. It may become law.

In the province of British Columbia the TCM practitioners and Acupuncturists Bylaws were approved by the provincial government on April 12, 2001. The governing body, College of Traditional Chinese Medicine Practitioners and Acupuncturists of British Columbia provides professional licensing. Acupuncturists began lobbying the B.C. government in the 1970s for regulation of the profession which was achieved in 2003.

Many other countries do not license acupuncturists or require they be trained.

Clinical Practice

Most modern acupuncturists use disposable stainless steel needles of fine diameter (0.007" to 0.020", 0.18mm to 0.51 mm), sterilized with ethylene oxide or by autoclave. The upper third of these needles is wound with a thicker wire (typically bronze) to stiffen the needle, provide a handle for the acupuncturist to grasp while inserting the needle, and also provide a surface to which dried mugwort will more easily adhere. The size and type of needle used, and the depth of insertion, depend on the acupuncture style being practiced.

Warming an acupuncture point, typically by moxibustion (the burning of mugwort), is a different treatment than acupuncture itself and is often, but not exclusively, used as a supplementing treatment. The Chinese term zhēn jǐu (針灸), commonly used to refer to acupuncture, comes from zhen meaning "needle", and jiu meaning "moxibustion". Moxibustion is still used in the 21st century to varying degrees among the schools of traditional Chinese medicine. For example, one well known technique is to insert the needle at the desired acupuncture point, attach dried mugwort to the external end of an acupuncture needle, and then ignite the mugwort. The mugwort will then smolder for several minutes (depending on the amount adhered to the needle) and conduct heat through the needle to the tissue surrounding the needle in the patient's body.

Example of Acupuncture Treatment

In western medicine, vascular headaches (the kind that are accompanied by throbbing veins in the temples) are typically treated with analgesics such as aspirin and/or by the use of agents such as niacin that dilate the affected blood vessels in the scalp, but in acupuncture a common treatment for such headaches is to stimulate the sensitive points that are located roughly in the center of the webs between the thumbs and the palms of the patient, the hť gǔ points. These points are described by acupuncture theory as "targeting the face and head" and are considered to be the most important point when treating disorders affecting the face and head. The patient reclines, and the points on each hand are first sterilized with alcohol, and then thin, disposable needles are inserted to a depth of approximately 3-5 mm until a characteristic "twinge" is felt by the patient, often accompanied by a slight twitching of the muscle between the thumb and hand. Most patients report a pleasurable "tingling" sensation and feeling of relaxation while the needles are in place. The needles are retained for 15-20 minutes while the patient rests, and then are removed.

In the clinical practice of acupuncturists, patients frequently report one or more of certain kinds of sensation that are associated with this treatment, sensations that are stronger than those that would be felt by a patient not suffering from a vascular headache: (1) Extreme sensitivity to pain at the points in the webs of the thumbs. (2) In bad headaches, a feeling of nausea that persists for roughly the same period as the stimulation being administered to the webs of the thumbs. (3) Simultaneous relief of the headache. (See Zhen Jiu Xue, p. 177f et passim.)

The Cochrane Collaboration, an international organization dedicated to evidence-based medicine, concluded from peer-reviewed research that "(o)verall, the existing evidence supports the value of acupuncture for the treatment of idiopathic headaches. However, the quality and amount of evidence are not fully convincing. There is an urgent need for well-planned, large-scale studies to assess the effectiveness and cost-effectiveness of acupuncture under real-life conditions." [10].

Scientific Research

Evidence- Based Medicine

There is scientific agreement that an evidence-based medicine (EBM) framework should be used to assess health outcomes and that systematic reviews with strict protocols are essential. Organizations such as the Cochrane Collaboration and Bandolier publish such reviews.

For the following conditions, the Cochrane Collaboration concluded there is insufficient evidence that acupuncture is beneficial, often because of the paucity and poor quality of the research and that further research would be needed to support claims for efficacy:

The Cochrane Collaboration review on the use of the P6 acupoint for the reduction of post-operative nausea and vomiting concluded that "compared with anti emetic prophylaxis, P6 acupoint stimulation seems to reduce the risk of nausea but not vomiting" [11]. A review conducted by the Scientific Review of Alternative Medicine, however, disagrees [12].

Bandolier at Oxford University states "There is no evidence from high quality trials that acupuncture is effective for the treatment of migraine and other forms of headache. The trials showing a significant benefit of acupuncture were of dubious methodological quality. Overall, the trials were of poor methodological quality." They also reported [13] "There were no high quality trials of acupuncture for stroke that showed that it was beneficial."

In practice, EBM does not demand that doctors ignore research outside its "top-tier" criteria [14].

NIH Consensus Statement

In 1997, the National Institutes of Health (NIH) issued a consensus statement on acupuncture that concluded that

there is sufficient evidence of acupuncture's value to expand its use into conventional medicine and to encourage further studies of its physiology and clinical value[15].

The statement was not a policy statement of the NIH [16] but rather the assessment of a panel whose impartiality has been questioned by members of the The National Council Against Health Fraud (NCAHF) [17]. (The NCAHF has itself been accused of bias [18], and two of their lawsuits against alternative medicine advocates were dismissed by courts as SLAPP-suits[19] [20] [21].)

The NIH consensus statement said that

the data in support of acupuncture are as strong as those for many accepted Western medical therapies

and added that

there is clear evidence that needle acupuncture is efficacious for adult postoperative and chemotherapy nausea and vomiting and probably for the nausea of pregnancy... There is reasonable evidence of efficacy for postoperative dental pain... reasonable studies (although sometimes only single studies) showing relief of pain with acupuncture on diverse pain conditions such as menstrual cramps, tennis elbow, and fibromyalgia...

The NIH consensus statement summarizes:

Acupuncture as a therapeutic intervention is widely practiced in the United States. While there have been many studies of its potential usefulness, many of these studies provide equivocal results because of design, sample size, and other factors. The issue is further complicated by inherent difficulties in the use of appropriate controls, such as placebos and sham acupuncture groups. However, promising results have emerged, for example, showing efficacy of acupuncture in adult postoperative and chemotherapy nausea and vomiting and in postoperative dental pain. There are other situations such as addiction, stroke rehabilitation, headache, menstrual cramps, tennis elbow, fibromyalgia, myofascial pain, osteoarthritis, low back pain, carpal tunnel syndrome, and asthma, in which acupuncture may be useful as an adjunct treatment or an acceptable alternative or be included in a comprehensive management program. Further research is likely to uncover additional areas where acupuncture interventions will be useful.

The NIH's National Center For Complementary And Alternative Medicine continues to abide by the recommendations of the NIH Consensus Statement [22], which some have criticized as outdated and superseded by more recent research [citation needed].

American Medical Association Statement

In 1997, the following statement was adopted as policy of the American Medical Association (AMA) after a report on a number of alternative therapies including homeopathy:[23]

"There is little evidence to confirm the safety or efficacy of most alternative therapies. Much of the information currently known about these therapies makes it clear that many have not been shown to be efficacious. Well-designed, stringently controlled research should be done to evaluate the efficacy of alternative therapies."

Note on Scientific Methodology and Acupuncture

One of the major criticisms of studies which purport to find that acupuncture is anything more than a placebo is that most such studies are not (in the view of critics) properly conducted. Many are not double blinded and are not randomized. However, double-blinding is not a trivial issue in acupuncture: since acupuncture is a procedure and not a pill, it is difficult to design studies in which the person providing treatment is blinded as to the treatment being given. The same problem arises in double-blinding procedures used in biomedicine, including virtually all surgical procedures, dentistry, physical therapy, etc.; the NIH Consensus Statement notes such issues with regard to sham acupuncture, a technique often used in studies purporting to be double-blinded. See also Criticism of evidence-based medicine. Tonelli, a prominent critic of EBM, argues that complementary and alternative medicine can never be EBM-based [24].

Safety, Risks

Because acupuncture needles penetrate the skin, many forms of acupuncture are invasive procedures, and therefore not without risk. However, injuries are rare among patients treated by trained practitioners. Forms of acupuncture such as the Japanese Tōyōhari and Shōnishin often use non-invasive techniques, in which specially-designed needles are rubbed or pressed against the skin. These methods are common in Japanese pediatric use.

Hematoma may result from accidental puncture of any circulatory structure. Nerve injury can result from the accidental puncture of any nerve. Brain damage or stroke is possible with very deep needling at the base of the skull. Also rare but possible is pneumothorax from deep needling into the lung, and kidney damage from deep needling in the low back. Needling over an occult sternal foramen (an undetectable hole in the breastbone which can occur in up to 10% of people) may result in a potentially fatal haemopericardium.

Certain acupuncture points have been shown to stimulate the production of adrenocorticotropic hormone (ACTH) and oxytocin; these points are contraindicated for use on pregnant women to avoid inducing abortion or harming the fetus.

Sometimes, when treating pain or using acupuncture as an anesthetic, a mild electrical current is applied to the needles. This stimulates the nerve cells in the area of the needles so that they become depleted of the chemicals needed to transmit signals. Prolonged stimulation of nerve cells in this way can cause irreversible damage.

The NIH consensus panel said:

"Adverse side effects of acupuncture are extremely low and often lower than conventional treatments."


"the incidence of adverse effects is substantially lower than that of many drugs or other accepted medical procedures used for the same condition. For example, musculoskeletal conditions, such as fibromyalgia, myofascial pain, and tennis elbow... are conditions for which acupuncture may be beneficial. These painful conditions are often treated with, among other things, anti-inflammatory medications (aspirin, ibuprofen, etc.) or with steroid injections. Both medical interventions have a potential for deleterious side effects but are still widely used and are considered acceptable treatments."

Needles that are not properly sterilized can transfer diseases such as HIV and hepatitis. Most acupuncturists in the USA use sterile one-time-use needles (rather than resterilizing needles after use). In 1996, the FDA changed the status of acupuncture needles from Class III to Class II medical devices, meaning that needles are regarded as safe and effective when used appropriately by licensed practitioners [25] [26].


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* Acupuncture: an ancient treatment for a current problem - An article discussing acupuncture as a treatment for back and neck pain

* The Skeptics dictionary on acupuncture

* Quackwatch article on acupuncture

* The Straight Dope on Acupuncture - A critical site

* A report from a physician who visited China after Nixon


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