Neurophysiological effects of constraint-induced movement therapy and motor function: A systematic review

Abstract

Background/Aims: There is a claim that improvements in motor function in people with stroke following constraint-induced movement therapy (CIMT) is due to compensation but not actually neurorestoration. However, few studies have demonstrated improvements in neurophysiological outcomes such as increased motor map size and activation of primary cortex, or their positive correlations with motor function, following CIMT. The aim of this study was to carry out a systematic review of CIMT trials using neurophysiological outcomes, and a meta-analysis of the relationship between the neurophysiological outcomes and motor function. Methods: The PubMed, PEDro and CENTRAL databases, as well as the reference lists of the included studies, were searched. The included studies were randomised controlled trials comparing the effect of CIMT on neurophysiological outcomes compared with other rehabilitation techniques, conventional therapy, or another variant of CIMT. Methodological quality was assessed using the PEDro scale. The data extracted from the studies were sample size, eligibility criteria, dose of intervention and control, outcome measurements, and time since stroke. Findings: A total of 10 articles (n=219) fulfilled the study inclusion criteria, all of which were used for narrative synthesis, and four studies were used in the meta-analysis. The methodological quality of the studies ranged from low to high. Strong, positive, and significant correlations were found between the neurophysiological and motor function outcomes in fixed effects (z=3.268, p=0.001; r=0.52, 95% confidence interval (CI) 0.227–0.994) and random-effects (z=2.106, p=0.035; r=0.54, 95% CI 0.0424–0.827) models. Conclusions: Randomised controlled trials evaluating the effects of CIMT on neurophysiological outcomes are few in number. Additionally, these studies used diverse outcomes, which makes it difficult to draw any meaningful conclusion. However, there is a strong positive correlation between neurophysiological and motor function outcomes in these studies.