Transcranial Electrical Stimulation (TCES) treatment involves applying electrodes to an individual’s scalp to allow electrical current to be applied and presumably stimulate the underlying cerebrum (Tan et al. 2006).

Table: Transcranial Electrical Stimulation Post-SCI Pain

Discussion

Despite the fact that TCES is a relatively new treatment for post-SCI pain, 3 RCTs (Tan et al. 2006; Fregni et al. 2006; Capel et al. 2003) have been published, all suggesting it may be useful in reducing SCI-related chronic pain. Each of these investigations employed a sham stimulation control condition, using modified equipment. Although patients in all 3 studies reported some pain relief following treatment, there was no comment on how long the treatments should continue or how often they should be used.

Tan et al. (2006) conducted a double-blind RCT with 38 SCI participants with either chronic musculoskeletal or neuropathic pain receiving either active transcranial electrical stimulation (TCES) or inactive TCES (sham control) over 21 days. The electrical stimulation was set at a subthreshold level ensuring that patients were blind to their treatment group. The study found that SCI patients receiving transcranial electrotherapy stimulation (n=18) experienced a significant reduction in post-SCI neuropathic and musculoskeletal average daily rating of pain intensity (p=0.03); however, there was no significant reduction in pain as noted on the Brief Pain Inventory (BPI).

Capel et al. (2003) reported transcranial electrostimulation resulted in lower pain scores on the McGill Pain Questionnaire for those in the treatment group (n=15), while those in the control group (n=15) reported no change. No statistical differences were noted across different pain types, although the authors did comment that subjects had greater relief of visceral pain following each active 4-day treatment phase of the study. Transcranial electrostimulation was associated with a reduction in the use of analgesics and antidepressants.  

Fregni et al. (2006)found similar results after examining the effects of transcranial direct current stimulation (tDCS) on central neuropathic pain. The treatment group (n=11), those receiving active tDCS for 5 consecutive days, experienced a significant reduction in pain relief over time (p<0.0001) compared to those receiving sham treatments (n=6)

Conclusion

• Based on three level 1 studies, there is strong evidence, of the benefits of transcranial electrical stimulation in reducing post-SCI pain.

• Transcranial electrical stimulation is effective in reducing post SCI neuropathic pain.