The efficacy of acupuncture has been and will likely remain a matter of ongoing debate. Some experts speculate that it may offer some benefit in pain management. However, a new report suggests that acupuncture offers no benefit to those suffering moderate to severe chronic knee pain.

The new report published in the October 1 issue of the Journal of the American Medical Association, describes a randomized, placebo-controlled clinical trial involving nearly 300 adults over the age of 50 who suffered chronic knee pain. The trial was designed to compare laser and needle acupuncture treatments for chronic knee pain to sham or “fake” procedures and to no procedure at all.

“Among patients older than 50 years with moderate to severe chronic knee pain, neither laser nor needle acupuncture conferred benefit over sham for pain or function,” the authors of the report wrote. “Our findings do not support acupuncture for these patients.”

The researchers who conducted the trial used sham acupuncture as a procedural placebo. The sham procedure was accomplished in a blinded manner with a robotic device that operated normally except without delivering the laser light in the laser acupuncture treatment routine. Neither the patients receiving sham treatments nor the operators delivering them knew that the procedures were fake. This arm of the study was included to account for “placebo effect,” a phenomenon whereby slight benefits may be conferred in the form of a patient’s belief that the treatment has provided a benefit but really has no measurable physiological change associated with it.

“Subjective measurements such as pain are particularly subject to placebo responses,” said senior author Kim Bennell, a professor of physiotherapy at the University of Melbourne in Australia. “This can be attributed to factors such as the treatment setting, patient expectations and optimism, the physician’s confidence in the treatment, and how the physician and patient interact.”

Patients enrolled in the study received 20-minute laser, needle, or sham acupuncture treatments twice each week for three months. Control subjects with chronic knee pain received no treatments. Knee pain was assessed by questionnaires at the study onset, at three months, and at one year after the study onset.

After three months, subjects receiving laser, needle, and sham laser acupuncture reported similar decreases in knee pain while walking, compared to the no-treatment control group. However, neither laser nor needle acupuncture provided significantly greater pain relief than did sham laser acupuncture, the researchers found. All pain decreases were gone by one year, regardless of procedure.

Audio of an interview with Bennell is available via The Jama Network.