High-quality clinical evidence indicates that although acupuncture seems more effective than usual care in the management of chronic low back pain, there is not much meaningful difference between true and sham acupuncture. This suggests that the benefits of acupuncture are mediated by the placebo response. An alternative explanation is that sham acupuncture is an active treatment and shares a mechanism of action with traditionally applied acupuncture. One plausible candidate for this mechanism is improvement in self-perception mediated through the sensory discrimination-like qualities of acupuncture. The authors’ goal was to compare the effects of acupuncture with a sensory discrimination training component to acupuncture without. 25 people with chronic low back pain were enroled in a randomised cross-over experiment. They compared the effect of acupuncture delivered when sensory discrimination is optimised to acupuncture delivered when it is not, on movement-related back pain immediately following each intervention. They found that the average pain intensity after participants had received acupuncture with sensory discrimination training (2.8±2.5) was less than when they received acupuncture without sensory discrimination training (3.6±2.0). This difference was statistically significant (after adjustment; mean difference=-0.8, 95% CI -1.4 to -0.3; p=0.011).
Their findings were consistent with the idea that acupuncture could provide specific benefit that is not reliant on precisely where the needles are inserted so much as that the patient attends to where they are inserted. They concluded that if this is the case, the placement of the needles might be better focused on the painful area and the need for penetration of the skin may be mitigated.