The Sham Challenge
This Clinical Kit looks at issues surrounding acupuncture and dry-needling research from the perspective of sham interventions to create an effective control group.
Medical researchers need a control group as a basis for experimental comparison. Typically as participants are enrolled in a trial, they are randomly allocated to experimental and control groups. The control or placebo group mimics all the intervention group's metrics (gender, age, background), thereby controlling for intervention bias or placebo effect. The control group either receives no treatment or sham treatment.
In pharmaceutical trials, it is very easy to create a reliable control group intervention; have two pills, both the same size, colour and scour marks, with only one containing the active ingredient being tested. It is much more difficult when providing acupuncture or dry needling. Even if unable to see, the research participant knows from the sensation felt, whether a needle has been inserted or not -just like your clients. For this reason, creating a true control group requires some form of intervention that mimics a needle insertion, physical sensation and visual. Acupuncture experiments often use the term verum (true) to identify the active acupuncture intervention, compared to sham, the control group.
Chronic Non-Specific LBP
For background information, in chronic non-specific low back pain, there is moderate evidence that verum acupuncture (and sham) is found to be better than no treatment and strong evidence that the use of acupuncture as an adjunct therapy is more effective than adjunct therapy by itself.
If we look at some research findings comparing verum acupuncture and sham, an outcomes difficulty becomes clear. Prior to 2008, there had been 3 high-quality papers looking a CLBP;
- Brinkhaus B, Witt CM, Jena S, et al. Acupuncture in patients with chronic low back pain: a randomized controlled trial. Arch Intern Med 2006;166: 450–7
- Haake M, Muller HH, Schade-Brittinger, et al. German acupuncture trials (GERAC) for chronic low back pain – randomized, multicenter, blinded, parallel-group trial with 3 groups. Arch Intern Med 2007;17:1892–8.
- Mendelson G, Selwood TS, Kranz H, et al. Acupuncture treatment of chronic back pain: a double-blind placebo-controlled trial. Am J Med 1983;74:49–55.
These studies have shown no significant difference between acupuncture and sham acupuncture for short and intermediate-term pain relief and functional improvement (n = 298, n = 1162 & n=190, respectively). The first two used superficial needle insertion at non-acupuncture points without stimulation, and the last one used superficial needle insertion with lignocaine 2% at non-acupuncture points as sham acupuncture, but they all involved actual needle insertions.
This lack of difference achieved between sham and real acupuncture, raises a research debate about how appropriate controls can be chosen and also a clinical debate, does it matter where needles are placed?. The problem is that studies using superficial needling outside of TCM meridians still stimulate non-specific pain-modulating pathways. In TCM practice, needling sensitive points (ah shi) in the region of pain are considered therapeutic benefits. Nabeta and researchers 2003 (1) compared acupuncture with sham acupuncture on tender points (ah shi points) in a chronic neck and shoulder pain group. They treated ah shi points once a week for 3 weeks. They found that there was a better short-term improvement using verum acupuncture but not a long-term superiority of verum over sham acupuncture.
Because of these powerful effects of sham needling, alternative controls must be considered. Historically other methods have been no treatment, sham interventions and other comparative interventions (massage, conventional therapy, transcutaneous electrical nerve stimulation, and spinal manipulation). As noted before, the most common sham intervention is minimal acupuncture at non-acupuncture points. A newer method is a non-penetrating sham acupuncture needle that recoils up into the needle handle, has a blunt tip and is non-penetrating. In a group of acupuncture-naive post-stroke participants, participants couldn’t determine whether they had received verum or sham acupuncture when using the Park Sham Device. To confirm the usefulness of this sham needle, it will need to be further trialled on different groups, but it will provide a useful tool to help determine acupuncture effectiveness.
When reading acupuncture and dry needling research, remember the type of control group employed and how this could influence the study's findings.
(1) Nabeta T, and Kawakita K. Relief of chronic neck and shoulder pain by manual acupuncture to tender points—a sham-controlled randomized trial. . Complementary Therapeutic Medicine 10: 2003.
Clinical Corner
I thought it would be good to include some interesting case studies from other practitioners. The 'Clinical Corner' frequency will depend upon the volume sent to me. If you like information in this format, please consider sending in your experiences. I will provide minor commentary if I feel I have something to add, similar to our case study presentations on the courses.
If you can stick to a format of headings, < b>Subjective Examination, Objective Examination (if possible, include relevant questionnaire measurements), Treatment Outcome, and Thoughts. Please limit submissions to around 300 words.
S/E A 15-year-old girl who had left knee surgery (patellar tendon reattachment) two years earlier, with ongoing pain and inability to walk any distances, unable to bear anything to touch the knee or the scar. No one could explain, and the surgeon had dismissed her. Her first statement was, “Do you think I should sue the surgeon?” She was unhappy generally, and more so with the pain, somewhat aggressive.
Objective Examination She had a transverse scar just lateral to the tibial tubercle insertion, maybe 2cm long, not particularly thick. The skin couldn’t be lifted or moved due to reduced mobility and skin hypersensitivity.
Treatment I offered some dry needling around the scar tissue. She wasn’t in favor of needling but provided consent. The first session was superficial, followed by progressively deeper insertion around the scar.
Method I used only two needles initially, then up to four. Initially placed about 10mm away from the scar, each visit progressively closer, either side of the scar. Depth: just into the skin, no more than 5mm deep. Length of insertion: initially only about 10 seconds each, one at a time. Later duration was about 5 minutes, and all needles in together. Initially, treatment was 3 days apart, then at weekly intervals.
Outcome Four sessions later she reported almost no knee pain and was able to return to netball without pain after the match as previously. There was no longer any skin hypersensitivity; the skin was mobile without any tethering around the scar, and one could touch the scar without the previous facial and bodily theatrics. She never mentioned the law again. Six months later the response was, “what knee problem?”
Peter Bryner
Burswood Health Clinic
Commentary A big thank you to Peter for the first Clinical Corner submission.
As it is a chronic presentation, it would be nice to have a multimodal tool like the Lower Limb Functional Index as part of her assessment. If it were a compensation situation, using a risk assessment tool like the Orebro Musculoskeletal Screening Questionnaire would be appropriate to evaluate the potential for delayed recovery. These tools are available here.
Clinically, she exhibits sensitisation symptoms of allodynia but not neuropathic, implying peripheral changes are more likely than central changes. The needling provided was superficial and targeted trauma tissue (scar), therefore probably provoking cutaneous A-delta and C fibres. The clinical changes were quick (2-3 weeks) and significant. With a resolution of pain, the function was restored promptly, even though you would have anticipated significant deconditioning effects given the prior 2 years of history. Something to consider....
Many thanks again to Peter for his case study and the interest it has generated. If you have your own comments, they will be posted on our Facebook page, and you are welcome to join the discussion. If you would like to send in a clinical case yourself, please do.
Recent Blogs of Interest
All the best,
Dr Doug Cary PhD
Specialist Musculoskeletal Physiotherapist
Clinical Director AAP Education
Examples include;
Resource 1. Calcific Tendinopathy: A personal and professional perspective
Resource 2. Fibromyalgia Syndrome
Resource 3. Needling and Infection Control Guide v3.2
Resource 4. Sleep Hygiene Guide - 16 Key Tips
Resource 5. Step-by-Step Guide to Managing Acute Back Pain
Resource 6. The Top 7 App Guide
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