Pelvis architecture and urinary incontinence in women

To examine anatomic features in the pelvic bones and muscles in women with urinary incontinence (UI).

Between October 2005 and January 2006, 212 consecutive women underwent pelvic computerized tomography in our center. Preceding the examination, all women completed a clinical and demographic questionnaire including detailed questions about UI. Several anatomic parameters using multiplanar reformation and three-dimensional techniques (volume rendering) were examined. We specifically evaluated different bony parameters, pelvic floor muscle angles, densities, and cross-sectional areas. Ninety-three women (46.5%) had UI; the remaining women served as the control group. A logistic regression model was used to evaluate risk factors for UI.

The mean age was 55.5 yr (range: 19-90). Women who suffered from UI were older (60.97 vs. 50.77 yr, p<0.0001), had higher body mass index (27.65 vs. 25.49, p<0.01), had more previous hysterectomies (21.5% vs. 6.5%, p<0.005), underwent more pelvic irradiation (9.7% vs. 1.8%, p<0.05), and had more diabetes mellitus (31.2% vs. 13.1%, p<0.005). Patient's age and previous hysterectomy were found to be the major clinical risk factors for UI (OR: 1.029, p=0.002; OR: 2.94, p=0.024, respectively). Logistic regression analysis on all clinical and morphologic variables yielded the following risk factors: pelvic-inlet diameter (OR: 1.216, p<0.0001), pelvic-inlet anterior-posterior diameter (OR: 1.109, p=0.003), pelvic-outlet diameter (OR: 1.077, p=0.011) and transverse perineal muscle cross-section diameter (OR: 0.773, p<0.0001).

Pelvic inlet and outlet dimensions are major risk factors for developing UI in women. These findings may lead to a better comprehension of the pathophysiology of UI in women.