Practice Patterns of Pelvic Floor Botulinum Toxin Use Among Clinical Experts

Objectives: Myofascial pelvic pain (MPP) is an under-recognized, under-treated etiology of pelvic pain characterized by painful pelvic floor muscles or tender points, with or without hypertonicity. While MPP has dramatic effects on quality of life, productivity, and health care utilization, little consensus exists on optimal treatment approaches, particularly when patients fail to improve with physical therapy. Limited data supports the use of onabotulinumtoxinA (BTA) tender point injection (TPI) for refractory cases. This study sought to use a modified Delphi technique to derive an expert consensus on effective practice patterns for application of pelvic floor BTA TPI.

Methods: Clinical experts were identified based on clinical volume, research publications, and publication of related patient-facing materials. Forty-six pelvic floor BTA experts were identified and 18 agreed to participate. A survey to characterize patterns of BTA TPI use from respondents (N=15) was analyzed using descriptive statistics. A secondary survey was distributed to respondents to clarify practices, with a total of 11 experts completing the secondary survey.

Results: Most respondents practice in academic hospitals (N=12/15, 80%) with the majority specialized in Obstetrics and Gynecology (N=14/15, 93%) with subspecialty Urogynecology (N=9/15) or Minimally Invasive Gynecologic Surgery (N=4/15) training (Table 1). Median number of TPI performed over the prior 6 months was 30 (range: 1-80). Respondents unanimously agreed BTA TPI is a useful treatment strategy for pelvic floor myofascial pain (N=15/15, 100%), with utility in global MPP (N=12/15, 80%), hypertonicity (N=14/15, 93%), and dyspareunia (N=15/15, 100%); respondents to the secondary survey endorsed utility in ilioinguinal/groin pain (N=6/11, 54%), anismus/dyssynergic defecation (N=8/11, 72%), and vaginismus (N=11/11, 100%). Most providers agreed that pelvic floor BTA should be considered after other therapeutics including physical therapy and vaginal relaxants/analgesics (N=9/11, 82%). Patient tolerance was the most common justification for injection in an operative setting, with most providers preferring the office vs. the operating room (N=8/11, 73%). Most providers did not endorse the need for test injection with anesthetic or steroid before proceeding to BTA (N=9/15, 60%). Providers agreed that BTA TPI should target tender points or hypertonic muscles when present, however in the setting of global symptoms, a templated injection pattern is appropriate (N=9/11, 82%); a subset of providers reported injecting specific muscles based on indication (N=4/11, 36%). All providers agreed clinical exam alone was sufficient for identification of injection sites (N=15/15, 100%); most reported mapping points of interest pre-operatively (N=12/15, 80%; N=10/11, 91%). Most providers perform BTA TPI bilaterally (N=10/11, 91%), typically taking a transvaginal approach (N=8/11, 72%) and using 100-200 units BTA per procedure (N=11/11, 100%).

Conclusions: While widespread expert consensus endorses the utility of BTA TPI for MPP, there exists a variety in injection approaches; future work to standardize TPI technique will allow for the study of optimal treatment efficacy and accessibility.