An international team of researchers wanted to determine the efficacy of laser and needle acupuncture for chronic knee pain. They conducted a Zelen-design clinical trial (randomization occurred before informed consent), in Victoria, Australia (February 2010-December 2012). Community volunteers (282 patients aged ≥50 years with chronic knee pain) were treated by family physician acupuncturists.
The treatments consisted of A) no acupuncture (control group, n = 71), B) needle (n = 70), C) laser (n = 71), and D) sham laser (n = 70) acupuncture. Treatments were delivered for 12 weeks. Participants and acupuncturists were blinded to laser and sham laser acupuncture. Control participants were unaware of the trial.
Primary outcomes were average knee pain (numeric rating scale, 0 [no pain] to 10 [worst pain possible]; minimal clinically important difference [MCID], 1.8 units) and physical function (Western Ontario and McMaster Universities Osteoarthritis Index, 0 [no difficulty] to 68 [extreme difficulty]; MCID, 6 units) at 12 weeks. Secondary outcomes included other pain and function measures, quality of life, global change, and 1-year follow-up. Analyses were by intention-to-treat using multiple imputation for missing outcome data.
At 12 weeks and 1 year, 26 (9%) and 50 (18%) participants were lost to follow-up, respectively. Analyses showed neither needle nor laser acupuncture significantly improved pain (mean difference; -0.4 units; 95% CI, -1.2 to 0.4, and -0.1; 95% CI, -0.9 to 0.7, respectively) or function (-1.7; 95% CI, -6.1 to 2.6, and 0.5; 95% CI, -3.4 to 4.4, respectively) compared with sham at 12 weeks. Compared with control, needle and laser acupuncture resulted in modest improvements in pain (-1.1; 95% CI, -1.8 to -0.4, and -0.8; 95% CI, -1.5 to -0.1, respectively) at 12 weeks, but not at 1 year. Needle acupuncture resulted in modest improvement in function compared with control at 12 weeks (-3.9; 95% CI, -7.7 to -0.2) but was not significantly different from sham (-1.7; 95% CI, -6.1 to 2.6) and was not maintained at 1 year. There were no differences for most secondary outcomes and no serious adverse events.
The authors drew the following conclusions: In patients older than 50 years with moderate or severe chronic knee pain, neither laser nor needle acupuncture conferred benefit over sham for pain or function. Our findings do not support acupuncture for these patients.
This is one of the methodologically best acupuncture studies that I have seen so far.
- its protocol has been published when the trial started thus allowing maximum transparency
- it is adequately powered
- it has a very clever study-design
- it minimizes bias in all sorts of ways
- it tests acupuncture for a condition that it is widely used for
- it even manages to blind acupuncturists by using one treatment arm with laser acupuncture
The results show quite clearly that acupuncture does have mild effects on pain and function that entirely rely on a placebo response.
Will acupuncturists learn from this study and henceforward stop treating knee-patients? Somehow I doubt it! The much more likely scenario is that they will claim the trial was, for this or that reason, not valid. Acupuncture, like most of alternative medicine, seems unable to revise its dogma.