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

Randomized, double-blinded, placebo-controlled, cross-over study.

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

Outpatient SCI clinic, New York, USA.

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.

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%).

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

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