Ninety-five cases with pelvic floor muscle hypertonicity were identified and matched. Sixty-five women suffered from both POP with or without UI and 30 women had UI only. Women sought care for a variety of pelvic floor symptoms. Among cases, 80/95 women (84.2%) presented with symptoms of pelvic pain. Forty-three percent of women with pain had pain alone whereas 57% had pain plus one or more pelvic floor symptoms (in decreasing order of frequency: urinary, bowel and/or prolapse complaints). Fifteen women (15.8%) had hypertonicity without a primary complaint of pelvic pain and instead presented with initial symptoms, in decreasing order of frequency, of urinary, bowel and/or prolapse complaints.
Most women were post-menopausal. Case patients were younger than controls (54 versus 59, p=0.002). On pelvic examination, vaginal atrophy was noted in 42.1% of cases and 45.7% of controls (p=0.616). Among cases, 15 women (15.8%) had provoked vestibulodynia, 81 (85.3%) had levator muscle spasm, 73 (76.8%) had obturator muscle spasm, 40 (42.1%) had coccygeus muscle spasm, 6 (6.3%) had bladder base tenderness and no women had documented increased anal sphincter muscle tone (voluntary or involuntary). Two women (2.1%) had exposure from prior prolapse procedures with synthetic mesh. Eleven women (11.6%) had synthetic suburethral mesh exposure from prior midurethral sling for incontinence.
Overall, univariate analysis showed being younger, having a history of depression, endometriosis, chronic constipation, dyspareunia, fibromyalgia, irritable bowel syndrome, musculoskeletal spine injury (from fall, fracture or motor vehicle accident), pelvic injury, chronic back pain, appendectomy, laparoscopy, hernia repair, back surgery and transobturator midurethral sling for UI to be significantly associated with hypercontracted pelvic floor in cases vs controls (Table 1). Multivariate analysis retained risk factors of decrease in age, history of depression, musculoskeletal spine injury (from fall, fracture or motor vehicle accident) and surgery for UI using a transobturator midurethral sling. Surgery for UI using a retropubic midurethral sling was protective against pelvic floor hypercontraction (Table 1).
Seventy-one percent (n=67) had urogynecologic surgery as a likely trigger for hypercontracted pelvic floor. All presented with subjective complaint of pelvic pain on initial visit. In the postoperative urogynecology surgery cases, age was not significantly different between cases and controls. Univariate analysis showed a history of depression, chronic constipation, dyspareunia, fibromyalgia, irritable bowel syndrome, musculoskeletal spine injury (from fall, fracture or motor vehicle accident), laparoscopy, back surgery and transobturator midurethral sling for UI to be significantly associated with hypercontracted pelvic floor in cases vs controls (Table 1). Retropubic midurethral sling was protective (p<0.001). In contrast, only the transobturator type of midurethral sling for UI remained a significant risk factor in the multivariate analysis.
Within the group of cases with pelvic floor hypercontraction (n=95), women who did not have urogynecologic surgery as a trigger (n=28) had fewer vaginal deliveries (mean 1.8 vs 2.3, p=0.043), a higher prevalence of interstitial cystitis (14.3 vs 1.5%, p=0.025), more chronic back pain (28.6 vs 9%, p=0.014) and a lesser prevalence of cholecystectomy (7.1 vs 28.4%, p=0.023).
The clinical predictive model for myofascial pain after urogynecologic surgery exhibited excellent predictive accuracy as reflected by the large area under the ROC curve (0.87; 95% CI: 0.80, 0.93). The resulting scoring algorithm from the model has a base score of 4 and assigned probability scores to demographic variables of depression (+3), endometriosis (+7), irritable bowel syndrome (+5) and musculoskeletal spine injury (+5). UI surgery using transobturator midurethral sling was also assigned a probability score of +7. In contrast, UI surgery using retropubic midurethral sling was assigned a protective probability score of minus 3. A total score of 7 or higher translated to an estimated probability of over 50% for persistent postoperative pelvic pain. The scoring algorithm showed good agreement between the observed and estimated probabilities (Table 2).