Can women without visible pubococcygeal muscle in MR images still increase urethral closure pressures?
OBJECTIVE
The purpose of this study was to determine if the ability to increase maximum urethral closure pressure (MUCP) with a pelvic muscle contraction is impaired in women without pubococcygeal muscle (PCM).


METHODS
This was a cross-sectional study of continent women comparing those with (n=28) and those without (n=17) PCM as identified by MR scans. A pelvic muscle contraction was performed simultaneously with recordings of urethral and bladder pressures.


RESULTS
Eighty-six percent of the women with PCM compared with 41% of the women without could volitionally increase (>5 cm H(2)O) their MUCP. Those with PCM generated a mean intraurethral pressure rise of 14.0 (10.8) cm H(2)O, compared with 6.2 (8.7) cm H(2)O in those without (P=.015). Among women who could produce a visible pressure rise, there was not a statistically significant difference between groups (with PCM=17.2 [7.8] cm H(2)O; without PCM=14.7 [7.5] cm H(2)O; P=.457).


CONCLUSIONS
Selective women without visible PCM can increase MUCP.
Miller
Janis M
JM
Department of Obstetrics and Gynecology, School of Nursing, University of Michigan, Ann Arbor, USA. janismm@umich.edu
Umek
Wolfgang H
WH
Delancey
John O L
JO
Ashton-Miller
James A
JA
D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D009119:Muscle Contraction / Q000502:physiology*; D009130:Muscle, Smooth / Q000033:anatomy & histology* / Q000502:physiology; D011312:Pressure; D014521:Urethra / Q000502:physiology*