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Both Real and ”Sham” Acupuncture Relieve Knee Pain

In a new study, researchers found that both traditional acupuncture and simulated acupuncture lessened the pain of knee osteoarthritis. Their evidence suggests that it may not be the acupuncture itself, but something about patients’ expectations and their interactions with acupuncturists, that helps reduce pain.

Osteoarthritis is the most common type of arthritis. It affects an estimated 27 million Americans age 25 and older. The condition causes pain, stiffness and swelling in the joints. Because the pain can be difficult to treat, some patients turn to alternative techniques such as acupuncture, an approach based on traditional Chinese medicine.

Acupuncture involves stimulating specific points on the body, usually by inserting thin needles through the skin. Today the most common type of acupuncture, called electroacupuncture, also sends pulses of electricity through the needles. The procedure is said to regulate the flow of qi (vital energy) along pathways known as meridians.

Several studies have shown that acupuncture can alleviate certain types of pain—sometimes more effectively than standard medical care. However, recent studies have also found that sham or placebo acupuncture can be just as effective as the real thing. Some scientists question whether the pain relief results from the procedure itself or from the attentiveness of the acupuncturist and the patient’s expectations.

Dr. Maria Suarez-Almazor of the University of Texas M.D. Anderson Cancer Center and her colleagues designed a 2-pronged study to look at this issue. They not only compared the effects of traditional acupuncture and a sham procedure, but also examined the impact of the acupuncturists’ communication style. The research was funded by NIH’s National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS).

As described in the September 2010 issue of Arthritis Care and Research, the study looked at 527 people, age 50 or older. All had painful osteoarthritis in the knee. None had received acupuncture in the past. The patients were randomly assigned to 3 groups: electroacupuncture, sham acupuncture or a control group placed on a waiting list. In the sham procedure, needles were shallowly inserted at non-meridian points and used minimal stimulation. Patients in the acupuncture and sham groups randomly received 1 of 2 communication styles from their acupuncturists. Some got a high-expectation style (such as "I think this will work for you") and others a neutral, uncertain style ("It really depends on the patient").

After 6 weeks of treatment, the researchers found that the acupuncture and sham procedures were equally effective in lessening knee pain. Both led to significant pain reduction compared to the control group. In addition, in both treatment groups, patients who got high-expectation communication showed a small but significant improvement in knee pain and satisfaction compared to those in the neutral group.

"The improvement in pain and satisfaction suggests that the benefits of acupuncture may be partially mediated through placebo effects related to the behavior of the acupuncturist," says Suarez-Almazor.

One possible limitation of the study, the scientists note, is that the sham procedure’s superficial needling may have had some pain-relieving effects. NIH-funded researchers are continuing to explore acupuncture’s clinical effects and how it might work.

—by Vicki Contie