The selection of dermatomes for sham (placebo) acupuncture points is relevant for the outcome of acupuncture studies: a systematic review of sham (placebo)-controlled randomized acupuncture trials

The findings of this review confirm our hypothesis. Acupuncture studies that employed verum and sham locations on overlapping dermatomes helped to create a mediocre to negative picture of acupuncture's efficacy. The segmental structure of the body with its interconnected reflex system offers an additional neurophysiological explanation for the effectiveness of acupuncture applied to structures segmentally innervated by the spinal and visceral nervous system. Further comparative acupuncture studies should be based on knowledge of segmental anatomy. In testing verum acupuncture versus sham acupuncture, the chosen sham acupuncture needling locations should be situated on non-overlapping dermatomes.