The efficacy of Graded Motor Imagery (GMI) for the management of Complex Regional Pain Syndrome (CRPS) is supported by evidence, but its treatment effect remains generally modest. Transcranial Direct Current Stimulation (tDCS) has been advocated as an adjunct intervention to enhance the effect of motor imagery approaches in pain populations.
The purpose of this study was to investigate the effectiveness of GMI+active tDCS compared with the GMI+sham tDCS in the treatment of CRPS type I.
A total of 22 patients (n=11/group) were randomly assigned to the experimental (GMI+tDCS) or placebo (GMI+sham tDCS) group. GMI treatments lasted 6 weeks; anodal tDCS was applied over the motor cortex for 5 consecutive days during the first 2 weeks and once a week thereafter. Changes in pain perception, quality of life, kinesiophobia, pain catastrophizing, anxiety and mood were monitored after 6 weeks of treatment (T1) and 1-month posttreatment (T2).
GMI+tDCS induced no statistically significant reduction in pain compared with GMI+sham tDCS. Although we observed significant group differences in kinesiophobia (P=0.012), pain catastrophizing (P=0.049), and anxiety (P=0.046) at T1, these improvements were not maintained at T2 and did not reached a clinically significant difference.
We found no added value of tDCS combined with GMI treatments for reducing pain in patients with chronic CRPS. However, given that GMI+sham tDCS induced no significant change, further studies comparing GMI+tDCS and tDCS alone are needed to further document tDCS’s effect in CRPS.
*Research Center of the Centre Hospitalier Universitaire de Sherbrooke (CRCHUS)
†Faculty of Medicine and Health Sciences, School of Rehabilitation
‡Department of Nuclear Medicine and Radiobiology, Faculty of Medicine and Health Sciences
§Faculty of Medicine and Health Sciences, School of Nursing, Université de Sherbrooke
#Research Center on Aging, CSSS-IUGS, Sherbrooke
∥Department of Rehabilitation, Faculty of Medicine, Université Laval
¶Center for Interdisciplinary Research in Rehabilitation and Social Integration (CIRRIS), Québec City, QC, Canada
Supported by grants from the Canadian Pain Society (CPS) Toronto, ON, Canada, the Quebec Pain Research Network (QPRN) Sherbrooke, QC, Canada, as well as the Inflammation and Pain Axis and the Faculty of Medicine and Health Sciences from the Université de Sherbrooke, Sherbrooke, QC, Canada. C.M. and G.L. were supported by salary awards from the Fonds de recherche Québec-Santé (FRQS) Montréal, QC, Canada. K.W. holds a Canada Research Chairs (CRC), Ottawa, ON, Canada. Y.T.-L. is a supported member of the Quebec Pain Research Network (QPRN), Sherbrooke, QC, Canada. The authors declare no conflict of interest.
Reprints: Yannick Tousignant-Laflamme, PT, PhD, Faculty of Medicine and Health Sciences, School of Rehabilitation, Université de Sherbrooke, 3001, 12e Avenue Nord, Z7, Sherbrooke, QC, Canada J1H 5N4 (e-mail: Yannick.Tousignant-Laflamme@USherbrooke.ca).
Received January 10, 2017
Received in revised form April 26, 2017
Accepted May 31, 2017