Am J Phys Med Rehabil. 2023 Mar 14. doi: 10.1097/PHM.0000000000002239. Online ahead of print.
OBJECTIVE: The aim of this umbrella review with meta-meta-analysis was to assess the effectiveness of orthopedic manual therapy in isolation on pain sensitization in patients with chronic musculoskeletal pain.
DESIGN: A systematic search was performed in different databases including systematic reviews with or without meta-analysis. The outcome measures included were pressure pain threshold, temporal summation, and conditioned pain modulation. We statistically synthesized the results of the different reviews through a random-effect meta-analysis of all standardized mean differences and the corresponding 95% confidence interval reported by each study.
RESULTS: For mechanical hyperalgesia, the meta-meta-analysis of three meta-analysis revealed a statistically significant small-moderate effect of orthopedic manual therapy, with no evidence of heterogeneity and moderate quality evidence. In terms of temporal summation, one meta-analysis revealed a statistically significant small effect of orthopedic manual therapy intervention, with moderate heterogeneity and low quality of evidence. Finally, one review without meta-analysis found that orthopedic manual therapy improved endogenous analgesia with low quality evidence.
CONCLUSION: Orthopedic manual therapy in isolation improved mechanical hyperalgesia with moderate quality evidence, as well as temporal summation and conditioned pain modulation with low quality evidence. However, its effects are limited only to immediate and short-term.