In their 2019 systematic review of spinal manipulative therapy (SMT) for chronic back pain, Rubinstein et al included 7 studies comparing the effect of SMT with sham SMT.
They defined SMT as any hands-on treatment of the spine, including both mobilization and manipulation. Mobilizations use low-grade velocity, small or large amplitude passive movement techniques within the patient’s range of motion and control. Manipulation uses a high-velocity impulse or thrust applied to a synovial joint over a short amplitude near or at the end of the passive or physiological range of motion. Even though there is overlap, it seems fair to say that mobilization is the domain of osteopaths, while manipulation is that of chiropractors.
The researchers found:
- low-quality evidence suggesting that SMT does not result in a statistically better effect than sham SMT at one month,
- very low-quality evidence suggesting that SMT does not result in a statistically better effect than sham SMT at six and 12 months.
- low-quality evidence suggesting that, in terms of function, SMT results in a moderate to strong statistically significant and clinically better effect than sham SMT at one month. Exclusion of an extreme outlier accounted for a large percentage of the statistical heterogeneity for this outcome at this time interval (SMD −0.27, 95% confidence interval −0.52 to −0.02; participants=698; studies=7; I2=39%), resulting in a small, clinically better effect in favor of SMT.
- very low-quality evidence suggesting that, in terms of function, SMT does not result in a statistically significant better effect than sham SMT at six and 12 months.
This means that SMT has effects that are very similar to placebo (the uncertain effects on function could be interpreted as the result of residual de-blinding due to a lack of an optimal placebo or sham intervention). In turn, this means that the effects patients experience are largely or completely due to a placebo response and that SMT has no or only a negligibly small specific effect on back pain. Considering the facts that SMT is by no means risk-free and that less risky treatments exist, the inescapable conclusion is that SMT cannot be recommended as a treatment of chronic back pain.