Pelvic floor muscle function in the standing position in women with pelvic floor dysfunction

Introduction and hypothesis Clinical assessment of the pelvic floor muscles (PFMs) in a standing position may provide a more valid representation of PFM function experienced by patients in daily life than assessment in the lying position. The primary aim of this study was to examine PFM function in a standing versus a lying position in parous women with any type of urinary incontinence and/or pelvic organ prolapse. Methods In this exploratory cross-sectional study, participant symptom status was determined using the Australian Pelvic Floor Questionnaire. Pelvic floor muscle function was assessed in standing and lying positions with a randomised order of testing. The primary outcome measure was vaginal squeeze pressure (VSP) using intra-vaginal manometry. Secondary outcomes included vaginal resting pressure, total PFM work and digital muscle testing. The difference between PFM function in a standing position compared with a lying position was analysed using paired t test or Wilcoxon's signed rank test. Results Vaginal squeeze pressure assessed with manometry was higher in a standing than in a lying position (p = 0.001): standing (mean [SD]) 24.90 [12.67], lying 21.15 [14.65]. In contrast, PFM strength on digital muscle testing was lower in a standing position than in a lying position. Conclusions This study has demonstrated that PFM function in a standing position is different from that in a lying position in women with pelvic floor dysfunction. Whether the higher VSP observed in a standing position reflects a true difference in strength between positions, or a higher pressure reading due to incorrect PFM contraction technique in a standing position is uncertain. Further research with larger cohorts and a measurement tool that can accurately distinguish a rise in intra-vaginal pressure from PFM contraction rather than increasing intra-abdominal pressure is required to confirm this difference, and the clinical significance of any difference.

Automated summary

Clinical assessment of pelvic floor muscle (PFM) function in standing position showed differences compared to lying position, indicating a potential impact on daily life activities for women with pelvic floor dysfunction. Further research with larger cohorts and accurate measurement tools is needed to confirm and understand the clinical significance of these differences.