Pelvic floor muscle training in women with stress urinary incontinence causes hypertrophy of the urethral sphincters and reduces bladder neck mobility during coughing

Abstract

Aims: The purpose of this study was to determine the effect of a 12-week pelvic floor muscle (PFM) training program on urethral morphology and mobility in women with stress urinary incontinence (SUI).

Methods: Forty women with SUI were randomly assigned to one of two groups: the treatment group received 12 weekly physiotherapy sessions during which they learned how to properly contract their pelvic floor muscles (PFMs) and a home exercise program was prescribed, reviewed, and progressed; the control group received no treatment. Before and after the 12-week study period, ultrasound imaging was used to evaluate bladder neck position and mobility during coughing and Valsalva maneuver in supine and in standing, as well as urethral morphology. Secondary outcome measures included a 3-day bladder diary, 30-min pad test, the Incontinence Impact Questionnaire (IIQ-7) and the Urogenital Distress Inventory (UDI-6).

Results: The women in the treatment group demonstrated reduced bladder neck mobility during coughing and increased cross-sectional area of their urethra after as compared to before the training. These changes were not evident in the control group. No differences in the resting position of the bladder neck or in bladder neck excursion during Valsalva maneuver were noted in either group. Concomitantly the women in the treatment group demonstrated significant improvements in the 3-day bladder diary and IIQ-7 after the PFM training and improved significantly more than the control group.

Conclusion: Physiotherapist-supervised PFM training reduces bladder neck motion during coughing, and results in hypertrophy of the urethral sphincter in women who present with SUI.

Keywords: exercise; pelvic floor; physiotherapy; stress urinary incontinence; ultrasound; urethra.

Fig. 1

CONSORT flow diagram.

Fig. 2

Vertical position of the bladder neck relative to the levator plate at rest. The perpendicular distance between the bladder neck and a line drawn between the inferior aspect of the pubic symphysis and the anorectal angle is presented. Measures were taken in supine and in standing both before (Pre-Rx) and after (Post-Rx) the 12-week study period. Bars indicate mean distance and whiskers indicate 95% confidence intervals for the mean. The bladder neck was located significantly higher in standing than in supine, as indicated by “*.” No change in this distance was seen after the study period as compared to before the study period.

Fig. 3

Displacement of the bladder neck during a maximal effort Valsalva maneuver. The change in perpendicular distance between the bladder neck and a line drawn between the inferior aspect of the pubic symphysis and the anorectal angle is presented for both groups before (Pre-Rx) and after (Post-Rx) the 12-week study period. Measures were taken in both the supine and standing positions. Bars indicate means and whiskers indicate the 95% confidence interval for the mean. In both groups and positions, there was more bladder neck displacement during the Valsalva noted at Post-Rx as compared to Pre-Rx, as indicated by “*.”

Fig. 4

Bladder neck displacement during coughing. The excursion of the bladder neck measured in the sagittal plane during coughing is presented before (Pre-Rx) and after (Post-Rx) the 12-week study period for both groups (No Rx, Rx) in both the supine and standing positions. Bars in indicate means and whiskers indicate 95% confidence intervals for the mean. In the treatment group, in both supine and standing, there was a significant reduction in bladder neck displacement during coughing after the study period compared to before the study period, as indicated by “*.” The control group did not demonstrate this same effect.

Fig. 5

Urethral wall cross sectional area. The cross sectional area of the urethral wall was measured in both groups before (Pre-Rx) and after (Post-Rx) the study period. Overall the MANOVA revealed a significant (P = 0.004) difference between groups, where the treatment (Rx) group showed an increase in cross sectional area but the control group (No Rx) did not. Univariate ANOVA results are presented here, where “*” indicates significant differences between Pre- and Post-Rx for each group at each specific point that was measured along the length of the urethra.