Pelvic floor myofascial pain severity and pelvic floor disorder symptom bother: is there a correlation?

Background Pelvic floor myofascial pain, which is predominantly identified in the muscles of the levator ani and obturator internus, has been observed in women with chronic pelvic pain and other pelvic floor disorder symptoms, and is hypothesized to contribute to their symptoms. Objectives To describe the prevalence of pelvic floor myofascial pain in patients presenting with pelvic floor disorder symptoms and to investigate whether severity of pelvic floor myofascial pain on examination correlates with degree of pelvic floor disorder symptom bother. Study Design All new patients seen at 1 tertiary referral center between 2014 and 2016 were included in this retrospectively assembled cross-sectional study. Pelvic floor myofascial pain was determined by transvaginal palpation of the bilateral obturator internus and levator ani muscles and scored as a discrete number on an 11-point verbal pain rating scale (range, 0–10) at each site. Scores were categorized as none (0), mild (1–3), moderate (4–6), and severe (7–10) for each site. Pelvic floor disorder symptom bother was assessed by the Pelvic Floor Distress Inventory short form scores. The correlation between these 2 measures was calculated using Spearman rank and partial rank correlation coefficients. Results A total of 912 new patients were evaluated. After exclusion of 79 with an acute urinary tract infection, 833 patients were included in the final analysis. Pelvic floor myofascial pain (pain rated >0 in any muscle group) was identified in 85.0% of patients: 50.4% rated as severe, 25.0% moderate, and 9.6% mild. In unadjusted analyses and those adjusted for postmenopausal status, severity of pelvic floor myofascial pain was significantly correlated with subjective prolapse symptoms such as pelvic pressure and heaviness but not with objective prolapse symptoms (seeing or feeling a vaginal bulge or having to push up on a bulge to start or complete urination) or leading edge. Severity of myofascial pain at several individual pelvic floor sites was also independently correlated with lower urinary tract symptoms, including pain in the lower abdomen (myofascial pain at all sites) and difficulty emptying the bladder (right obturator internus and left levator ani); and with defecatory dysfunction, including sensation of incomplete rectal emptying (pain at all sites combined and the right obturator internus), anal incontinence to flatus (pain at all sites combined), and pain with defecation (pain at all sites combined, and the right obturator internus and left levator ani). Conclusion Pelvic floor myofascial pain was common in patients seeking evaluation for pelvic floor disorder symptoms. Location and severity of pelvic floor myofascial pain was significantly correlated with degree of symptom bother, even after controlling for postmenopausal status. Given the high prevalence of pelvic floor myofascial pain in these patients and correlation between pain severity and degree of symptom bother, a routine assessment for pelvic floor myofascial pain should be considered for all patients presenting for evaluation of pelvic floor symptoms.