In December of 2013, the New England Journal of Medicine published a randomized controlled trial demonstrating that partial meniscectomy was no better than a sham procedure involving just the arthroscopy. Interestingly, typical knee acupuncture involves fine needle insertion into locations that include those used by arthroscopic instruments in both treatment and control groups of this study. We should consider that the authors may have inadvertently provided a very strong knee-specific acupuncture-type treatment with their instruments, and this may account for some of what was referred to as the “placebo effect” in the trial.
In December of 2013, the New England Journal of Medicine published a randomized controlled trial demonstrating that partial meniscectomy, a procedure using arthroscopic probes to repair the meniscus within the knee, was no better than a sham procedure involving just the arthroscopy. The authors suggest these findings are related to the profound placebo effect of performing surgery itself, and that the surgical interventions on the meniscus were irrelevant. According to acupuncture theory, the incision points used by the surgeons for both the real and sham procedures are at the same locations as acupuncture points used for thousands of years in the treatment of knee pain. Could it be that the sham procedure accidentally provided an acupuncture-like stimulation that was as effective as the surgery itself?
Is knee meniscus surgery helpful?
For decades, people with chronic knee pain have benefitted from surgical procedures to repair known deformities. These procedures range from minimally invasive procedures such as arthroscopy (a term describing the use of probes to perform surgery within the knee joint itself) to full blown knee replacement surgery. Generally, people seem to get better with these procedures, so over the past few decades their use has skyrocketed up to about 1 million procedures in 2006. About half of these procedures were performed for tears of the meniscus, which is a small piece of cartilage that cushions the bones of the knee. For this reason, the results of this study can have large implications for the way we treat knee pain.
What is the placebo effect?
Most medicines are evaluated for their efficacy using a placebo-controlled trial, where some people are given the real medicine while others are given a “fake” medicine called a placebo, and the study participants don’t know which medicine they are taking. This is done because people generally get better when they feel that they are being treated with a medicine that works, regardless of any true efficacy. This was demonstrated very elegantly in 2008 by Ted Kaptchuk, Professor of Medicine at Harvard University, in which people with irritable bowel syndrome were given placebo medications and told up front that the medications were inactive but that they would be effective. Those patients did better than one of the leading irritable syndrome bowel drugs at the time.
With surgical procedures, placebo-controlled trials become ethically challenging. While it is considered safe to give a placebo tablet to a patient in order to study a new medication, a placebo surgery, a fake surgical intervention without any understood benefit, has the potential to harm the patient and is thus harder to study. Because of this, surgical procedures are rarely evaluated using placebo-controlled trials. The authors of this study managed to perform one of the rare placebo-controlled surgical trials, and the results were striking.
The results of the study
Raine Sihvonen, MD of Hatanpaa Hospital in Tampere, Finland, conducted a trial that randomized participants into two groups, where one underwent a meniscus repair procedure and the other underwent the placebo procedure. The placebo procedure involved the same levels of anesthesia as the true surgery, and surgical incisions were made into the knee and arthroscopic probes were inserted as well. The only difference between the two surgeries was that the placebo surgery did not repair the meniscus. On follow up, both groups did much better than before the procedure, but there was no statistically significant difference between the two groups. The implication of this is that arthroscopic meniscus surgery was ineffective in treating knee pain.
An East-West explanation
Acupuncture has been demonstrated to be effective in treating knee pain when compared to non-penetrating control treatment. Interestingly, typical knee acupuncture involves fine needle insertion into locations that include those used by arthroscopic instruments in both treatment and control groups of this study (See Figure 1). For a stronger effect, larger needles can be used and physical manipulation or electrical stimulation of those needles can strengthen the effect even further.
Both the real surgery and the placebo surgery in this study involved the placement of relatively large probes into the knee through known acupuncture points, followed by heavy manipulation of the probes to perform the surgery itself. In effect, the authors may have inadvertently provided a very strong knee-specific acupuncture treatment with their instruments.
Instead of focusing on the negative implications for meniscectomy, one might look into providing the same clinical improvement without the cost and morbidity associated with arthroscopic procedures. Bruce Moseley, MD reported in the same journal in 2002 that simply performing the three 1 cm incisions was enough to have an indistinguishable effect from arthroscopic debridement for knee osteoarthritis. It is possible that needle stimulation to those points can provide the same effect.
 Sihvonen R et al, “Arthroscopic partial miniscectomy versus sham surgery for a degenerative meniscal tear.” The New England Journal of Medicine, 2013 Dec 26;369(26):2515-24.
 Kim S, Bosque J, Meehan JP, Jamali A, Marder R. Increase in outpatient knee arthroscopy in the United States: a comparison of National Surveys of Ambulatory Surgery, 1996 and 2006. J Bone Joint Surg Am. 2011 Jun 1;93(11):994-1000. doi: 10.2106/JBJS.I.01618.
 Kaptchuk TJ, Friedlander E, Kelley JM, Sanchez MN, Kokkotou E, et al. (2010) Placebos without Deception: A Randomized Controlled Trial in Irritable Bowel Syndrome. PLoS ONE 5(12): e15591. doi: 10.1371/journal.pone.0015591
 Witt, C et al, “Acupuncture in patients with osteoarthritis of the knee: a randomised trial.” The Lancet, Volume 366, Issue 9480, 9-15 July 2005, Pages 136-143.
 Moseley, Bruce et al, “A controlled trial of arthroscopic surgery for osteoarthritis of the knee.” The New England Journal of Medicine, 2002; 347:81-88.
By Andrew Shubov, MD
UCLA Center for East-West Medicine, Fellow
Rosana Chan, MPH, UCLA Fielding School of Public Health
UCLA Center for East-West Medicine, Administrator
Vivianne Chang, Human Biology and Society B.S., UCLA 2014
UCLA Center for East-West Medicine, Administrative Assistant