Effects of transcranial direct current stimulation followed by exercise on neuropathic pain in chronic spinal cord injury: a double-blinded randomized controlled pilot trial

Study design: Double-blinded randomized controlled pilot trial. Objectives: The present study aimed to investigate the effects of multiple sessions of tDCS followed by exercise on neuropathic pain and brain activity in individuals with chronic SCI. Setting: Rehabilitation center in Taipei, Taiwan. Methods: Twelve individuals with neuropathic pain after SCI were randomized into the experimental (real) or control (sham) tDCS group. All participants received 12 sessions of real or sham tDCS, and moderate upper body exercises over 4–6 weeks. Pain intensity, characters of pain, self-rating change of pain, brain activity, and quality of life were assessed at pre, posttest, and 4-week follow-up. Results: The between-group differences (95% CI) of pain intensity at posttest and at 4-week follow-up were −2.2/10 points (−3.0 to 1.0, p = 0.060) and −2.0/10 points (−5.0 to −0.4, p = 0.035), respectively. The between-group differences of paresthesia/dysesthesia pain character were −2.0/10 points (−3.2 to 1.0, p = 0.053) at posttest and −2.3/10 points (−5.0 to 2.5, p = 0.054) at follow-up. No significant changes in brain activity and quality of life were noted at post-intervention and follow-up in both groups. Conclusions: The multiple sessions of anodal tDCS combined with moderate upper body exercise were feasible for individuals with neuropathic pain after spinal cord injury. However, the analgesic effect was not superior to exercise alone after 12 sessions of intervention, and the beneficial effect was observed at 4-week follow-up.