Abstract 7: Scrambler Therapy for Treatment of Post Stroke Pain

Abstract

Objective: Infarcts involving sensory pathways can result in a post-stroke pain syndrome that is often refractory to traditional medical therapy. Scrambler Therapy (ST) is a noninvasive electroanalgesia device effectively used to treat peripheral neuropathy; however, data is scarce regarding its use in the central nervous system. In this pilot, we evaluate the efficacy of ST to treat post-stroke pain syndromes. Methods: Twenty patients with a history of stroke resulting in contralateral pain were enrolled and randomized to receive ST or Sham as an adjunct to their current medication regimen. Participants underwent 5 consecutive sessions, each lasting 40 minutes. Pain scores were recorded at baseline, as well as before and after each session using a Numeric Rating Scale (0-10). The study was double-blinded to both the participant and operator. Following treatment, pain scores were collected weekly for 4 weeks. Student’s t tests were used to compare scores at: baseline, immediately post-treatment #5, and at 4 week follow-up, between groups as well as the change in pain score between individuals. Results: To date, 15 patients have been enrolled and completed the intervention; 10 have completed longer-term follow-up. The average age of the cohort was 57.8 years; 47% were male; 53% black; and the average time from stroke was 26 months. Participants randomized to ST (n=7) had a mean pain score of 6.52 at baseline; the Sham group (n=8) had a mean score of 5.83. The ST group had a mean change from initial score to score after 5 days of treatment of -4.17 (SD 2.64), while the Sham group had a mean change in score of -1.03 (SD 1.42). For patients completing follow-up, the ST group (n=5) saw a mean change pain score from baseline to follow-up of -3.37 (SD 1.71). The Sham group (n=5) a mean change of -0.37 (SD 0.34). Differences in change in score were significant between groups at both time points (p=0.01 and 0.005 respectively). Conclusion: There is a significant difference in both acute and longer-term pain reduction for patients with post-stroke pain who undergo treatment using ST compared to Sham that suggests it may be an effective treatment option. Larger studies are needed to evaluate confounders such as stroke location, time from stroke, and concomitant treatment with medications.