Effects of joint mobilisation on clinical manifestations of sympathetic nervous system activity: a systematic review and meta-analysis

Background A potential mechanism of action of manual therapy is the activation of a sympathetic-excitatory response. Objective To evaluate the effects of joint mobilisation on changes in clinical manifestations of sympathetic nervous system activity. Data sources MEDLINE, EMBASE, AMED, CINAHL, EBSCO, PubMed, PEDro, Cochrane Collaboration Trials Register, Cochrane Database of Systematic Reviews and SCOPUS databases. Study selection Randomised controlled trials that compared a mobilisation technique applied to the spine or the extremities with a control or placebo. Data extraction and data synthesis Human studies collecting data on skin conductance or skin temperature were used. Data were extracted by two reviewers. Risk of bias was assessed using the Cochrane guidelines, and quality of evidence was assessed using the GRADE approach. Standardised mean differences (SMD) and random effects were calculated. Results Eighteen studies were included in the review and 17 were included in the meta-analysis. The meta-analysis found a significant increase in skin conductance [SMD 1.21, 95% confidence interval (CI) 0.88 to 1.53, n= 269] and a decrease in temperature (SMD 0.92, 95% CI -1.47 to -0.37, n= 128) after mobilisation compared with the control group. An increase in skin conductance (SMD 0.73, 95% CI 0.51 to 0.96, n= 293) and a decrease in temperature (SMD -0.50, 95% CI -0.82 to -0.18, n = 134) were seen after mobilisation compared with placebo. The risk of bias was generally low, but the heterogenicity of the results downgraded the level of evidence. Limitations Most trials (14/18) were conducted on asymptomatic healthy subjects. Conclusion There is moderate evidence suggesting a sympatho-excitatory effect of joint mobilisation. (C) 2020 Chartered Society of Physiotherapy. Published by Elsevier Ltd. All rights reserved.