Cupping therapy for non-specific chronic low back pain

Cupping is a so-called alternative medicine (SCAM) that has been around for millennia in many cultures. We have discussed it repeatedly on this blog (see, for instance, here, here, and here). This new study tested the effects of dry cupping on pain intensity, physical function, functional mobility, trunk range of motion, perceived overall effect, quality of life, psychological symptoms, and medication use in individuals with chronic non-specific low back pain.

Ninety participants with chronic non-specific low back pain were randomized. The experimental group (n = 45) received dry cupping therapy, with cups bilaterally positioned parallel to the L1 to L5 vertebrae. The control group (n = 45) received sham cupping therapy. The interventions were applied once a week for 8 weeks.

Participants were assessed before and after the first treatment session, and after 4 and 8 weeks of intervention. The primary outcome was pain intensity, measured with the numerical pain scale at rest, during fast walking, and during trunk flexion. Secondary outcomes were physical function, functional mobility, trunk range of motion, perceived overall effect, quality of life, psychological symptoms, and medication use.

On a 0-to-10 scale, the between-group difference in pain severity at rest was negligible: MD 0.0 (95% CI -0.9 to 1.0) immediately after the first treatment, 0.4 (95% CI -0.5 to 1.5) at 4 weeks and 0.6 (95% CI -0.4 to 1.6) at 8 weeks. Similar negligible effects were observed on pain severity during fast walking or trunk flexion. Negligible effects were also found on physical function, functional mobility, and perceived overall effect, where mean estimates and their confidence intervals all excluded worthwhile effects. No worthwhile benefits could be confirmed for any of the remaining secondary outcomes.

The authors concluded that dry cupping therapy was not superior to sham cupping for improving pain, physical function, mobility, quality of life, psychological symptoms or medication use in people with non-specific chronic low back pain.

These results will not surprise many of us; they certainly don’t baffle me. What I found interesting in this paper was the concept of sham cupping therapy. How did they do it? Here is their explanation:

For the experimental group, a manual suction pump and four acrylic cups size one (internal diameter = 4.5 cm) were used for the interventions. The cups were applied to the lower back, parallel to L1 to L5 vertebrae, with a 3-cm distance between them, bilaterally. The dry cupping application consisted of a negative pressure of 300 millibars (two suctions in the manual suction pump) sustained for 10 minutes once a week for 8 weeks.

In the control group, the exact same procedures were used except that the cups were prepared with small holes < 2 mm in diameter to release the negative pressure in approximately 3 seconds. Double-sided adhesive tape was applied to the border of the cups in order to keep them in contact with the participants’ skin.

So, sham-controlled trials of cupping are doable. Future trialists might now consider the inclusion of testing the success of patient-blinding when conducting trials of cupping therapy.