Altered muscle activation patterns in symptomatic women during pelvic floor muscle contraction and Valsalva manouevre.
OBJECTIVE
To investigate the muscle activation patterns of the abdomino-pelvic region used by incontinent women during a pelvic floor muscle (PFM) contraction and a Valsalva manouevre compared to healthy, asymptomatic subjects.


METHODS
Thirteen incontinent (symptomatic) women, identified using ultrasound to be consistently depressing the bladder base during PFM contraction, and thirteen continent women (asymptomatic) able to perform an elevating PFM contraction were assessed using surface electromyography (EMG) of the PFM, abdominal and chest wall muscles and vaginal and intra-abdominal pressure (IAP) measurements during PFM contraction and Valsalva under ultrasound surveillance.


RESULTS
There were no differences between groups in age, parity or BMI. There was a difference in muscle activation patterns between groups (P = 0.001). During PFM contraction the PFM were less active and the abdominal and chest wall muscles were more active in the symptomatic group. During Valsalva, the PFM and EO were more active in the symptomatic group but there was no difference in the activation of the other muscles between groups. There was a significant interaction (group x pressure) for change in IAP (P = 0.047) but no significant interaction for change in vaginal pressure (VP) (P = 0.324).


CONCLUSIONS
The symptomatic women displayed altered muscle activation patterns when compared to the asymptomatic group. The symptomatic women were unable to perform a voluntary PFM contraction using a localized muscle strategy, instead activating all the muscles of the abdomino-pelvic cavity. The potential for muscle substitution strategies reinforces the need for close attention to specificity when prescribing PFM exercise programs.
School of Physiotherapy, Curtin University of Technology, Western Australia.
Judith A
JA
Thompson
School of Physiotherapy, Curtin University of Technology, Western Australia.
Peter B
PB
O'Sullivan
School of Physiotherapy, Curtin University of Technology, Western Australia.
N Kathryn
NK
Briffa
School of Physiotherapy, University of South Australia, Adelaide, South Australia.
Patricia
P
Neumann
D000328:Adult; D005260:Female; D006801:Humans; D009119:Muscle Contraction; D017773:Pelvic Floor / Q000503:physiopathology*; D014549:Urinary Incontinence / Q000503:physiopathology*; D014636:Valsalva Maneuver