Botulinum injections for myofascial pelvic pain.

INTRODUCTION AND HYPOTHESIS: The aim of this study was to assess the impact of botulinum toxin injection in women with myofascial pelvic pain (MFPP) syndrome of the pelvic floor who had failed conservative treatment. METHODS: This was a retrospective descriptive observational study of 48 consecutive patients receiving botulinum toxin to the pelvic floor for MFPP syndrome in a tertiary teaching hospital over an 8-year period. Trigger points were identified, and botulinum toxin was injected into the pelvic floor at the trigger points in doses ranging from 50 to 200 units. The patient-reported global impression of improvement scale was used to evaluate the success at follow-up, and adverse effects were recorded. RESULTS: Forty-six women attended for follow-up at 3-6 months. Of these, 34 (74%) reported an improvement in their symptoms (slightly better, much better, very much better), 12 (26%) had no change, and no patients reported worsening of symptoms. One patient (2%) reported transient postoperative faecal incontinence, which resolved after 2 weeks. There appeared to be no difference in outcome between the doses. CONCLUSIONS: Botulinum toxin injection into the pelvic floor of women with MFPP appears to be beneficial in those who have failed conservative treatment. Prospective studies, including dose-finding studies, are now required.