Results of the first large scale study of patients with chronic low back pain found that transcranial direct current stimulation (tDCS) does not reduce pain intensity or disability. The new research was published last month in the British Medical Journal. The study involved 135 subjects with low back pain who were randomized into 2 groups. Half received 20 minutes of left motor cortex tDCS stimulation for 5 days, while the other half received a sham stimulation (including 5 seconds of current to mimic the physical sensations of tDCS) for the same amount of time. The researchers measured pain levels with a visual analogue scale and overall disability with the Oswestry Disability Scale at several time points and found no difference between groups with respect to either measure.
tDCS is a noninvasive brain stimulation technique that has gained attention for its potential to enhance cognition as well as treat a wide range of conditions, including depression, stroke, and pain. Unlike TMS—a more expensive technique that elicits neuronal firing—tDCS exerts a more subtle effect on the brain by altering levels of neuronal excitability below the threshold of firing. The latest study notwithstanding, not everyone is convinced that it’s time to abandon tDCS for pain treatment. Citing concerns about the stimulation protocol, study population, and other study design issues, Felipe Fregni of Harvard Medical School said, “Due to the methodology used in this trial, we cannot conclude that tDCS is ineffective in treating chronic low back pain.”
Read more on the varying points of view concerning tDCS here.
View related content here.