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Updated: May 28, 2026
Nerve-sparing Mid-urethral Obstruction (NeMO) in Female Small Rodents
Published on: April 25, 2017
Continent women have better urethral neuromuscular function than those with stress incontinence
Kimberly Kenton1, Elizabeth Mueller, Linda Brubaker
1Division of Female Pelvic Medicine & Reconstructive Surgery, Department of Obstetrics & Gynecology, Loyola University Stritch School of Medicine, 2160 South First Avenue, Maywood, IL 60153, USA. kkenton@lumc.edu
Introduction And Hypothesis:
The objective of this study is to describe urethral neuromuscular function using concentric needle electromyography (EMG) in stress incontinent (SUI) and asymptomatic women.
Methods:
Following Institutional Review Board approval, we recruited SUI and asymptomatic women without urinary incontinence. Participants underwent quantitative urethral EMG and urodynamic testing.
Results:
Sixty-seven women (37 SUI, 30 continent) with mean ± SD age of 44 ± 12 years participated. Nearly all EMG parameters showed significant differences between continent and SUI women consistent with better motor unit recruitment in continent women. Continent women had larger-amplitude, longer-duration motor unit action potentials (MUP) with increased turns and better MUP recruitment during bladder filling (P < .05). Increasing age was inversely correlated with nearly all MUP parameters (P < .05), suggesting MUP to be consistent with neuropathy.
Conclusions:
We found significant differences in multiple MUP parameters in urethral sphincter between continent and stress incontinent women, suggesting continent women have better urethral innervation. We also found significant neuropathic MUP changes with advancing age, regardless of continence status.
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