Treatment of at-level spinal cord injury pain with botulinum toxin A.

[STUDY DESIGN] Randomized, double-blinded, placebo-controlled, cross-over study.

[OBJECTIVE] To explore whether botulinum toxin A (BoNTA) could be effective for treating at-level spinal cord injury (SCI) pain.

[SETTING] Outpatient SCI clinic, New York, USA.

[METHODS] Participants were randomized to receive subcutaneous injections of either placebo or BoNTA with follow-up (office visit, telephone, or e-mail) at 2, 4, 8, and 12 weeks to assess the magnitude of pain relief post injection. Crossover of participants was then performed. Those who received placebo received BoNTA, and vice versa, with follow-up at 2, 4, 8, and 12 weeks.

[RESULTS] Eight participants completed at least one of the two crossover study arms. Four completed both arms. The median age of the eight participants was 45 years (range 32-61 years) and 75% were male. All had traumatic, T1-L3 level, complete SCI. Although our data did not meet statistical significance, we noted a higher proportion of participants reporting a marked change in average pain intensity from baseline to 8 and 12 weeks post-BoNTA vs. post-placebo (33% vs. 0%). At 2 and 4 weeks post-BoNTA, almost all participants reported some degree of reduced pain, while the same was not seen post-placebo (83% vs. 0%).

[CONCLUSION] The subcutaneous injection of BoNTA may be a feasible approach for the control of at-level SCI pain and is worthy of further study.

[SPONSORSHIP] The onabotulinumtoxinA (BOTOX) used in this study was provided by Allergan (Irvine, CA).