A first of its kind randomized, controlled, double-blinded clinical trial has confirmed the effectiveness of botulinum toxin A in combination with physical therapy in treating chronic sciatica and buttock pain arising from piriformis syndrome. The study was led by Loren Fishman, MD, assistant clinical professor at Columbia Medical School and medical director of Manhattan Physical Medicine and Rehabilitation. The work further confirmed the validity of electromyography (EMG), or electrophysiological assessment of muscles and nerves, as a technique for differential diagnosis of piriformis syndrome and then for guiding the injection of botulinum toxin. The findings appear in this month’s edition of the journal Muscle and Nerve.
Although piriformis syndrome is responsible for anywhere from 10% to 50% of cases of sciatica, most clinicians have found it difficult to diagnose. In the current 3 month trial, 56 patients received electromyography in conjunction with a test of the piriformis muscle to rule out spinal causes of sciatica and narrow the diagnosis to piriformis syndrome. 28 patients received EMG-guided botulinum injection in conjunction with weekly physical therapy. The remaining control group received placebo injection with the same PT routine. An 81.5% improvement in reported pain levels was observed in the cohort who received the guided botulinum injections, while the control group reported no significant improvement.
Read a news story about the findings.
The journal abstract may be read here.
Posted on August 16, 2017