TY - JOUR
T1 - Effects of delivery mode and age on motor unit properties of the external anal sphincter in women
AU - Li, Xuhong
AU - Zhang, Chuan
AU - Dias, Nicholas
AU - Liu, Jiaojiao
AU - Hu, Fang
AU - Yang, Shuo
AU - Zhou, Yanhua
AU - Zhang, Yingchun
N1 - Publisher Copyright:
© 2019, The International Urogynecological Association.
PY - 2019/1/1
Y1 - 2019/1/1
N2 - Introduction and hypothesis: This study aimed to assess the individual and interactive effects of delivery mode and age on the function of the external anal sphincter (EAS) by analyzing the motor unit properties with intramuscular electromyography (EMG). Results are expected to improve the understanding of delivery-related occult obstetric EAS injuries and its development over the aging process and further support early clinical detection and intervention. Methods: A total of 49 postpartum women were recruited into four test groups according to their age and delivery mode: young vaginal delivery (Y-VD), elderly vaginal delivery (E-VD), young cesarean section (Y-CS), and elderly cesarean section (E-CS) groups. Anorectal ultrasonography, manometry, and intramuscular EMG were employed for comprehensive evaluation of EAS function. Results: No significant difference in anorectal ultrasonography and most manometry measurements was associated with delivery age or mode. Intramuscular EMG, however, revealed a statistically significant difference in the characteristics of motor unit potentials (MUPs), including duration, turns, phases, and multiphase wave ratio between four subject groups. No significant interaction effect between age and delivery mode was found. Conclusions: Delivery mode and age have a significant effect on the neuromuscular function of the EAS, suggesting a potential protectiveness of cesarean section against impairment to the EAS. Our results do not provide significant evidence regarding the interaction effect of delivery mode and age; further investigations are needed to confirm this conclusion.
AB - Introduction and hypothesis: This study aimed to assess the individual and interactive effects of delivery mode and age on the function of the external anal sphincter (EAS) by analyzing the motor unit properties with intramuscular electromyography (EMG). Results are expected to improve the understanding of delivery-related occult obstetric EAS injuries and its development over the aging process and further support early clinical detection and intervention. Methods: A total of 49 postpartum women were recruited into four test groups according to their age and delivery mode: young vaginal delivery (Y-VD), elderly vaginal delivery (E-VD), young cesarean section (Y-CS), and elderly cesarean section (E-CS) groups. Anorectal ultrasonography, manometry, and intramuscular EMG were employed for comprehensive evaluation of EAS function. Results: No significant difference in anorectal ultrasonography and most manometry measurements was associated with delivery age or mode. Intramuscular EMG, however, revealed a statistically significant difference in the characteristics of motor unit potentials (MUPs), including duration, turns, phases, and multiphase wave ratio between four subject groups. No significant interaction effect between age and delivery mode was found. Conclusions: Delivery mode and age have a significant effect on the neuromuscular function of the EAS, suggesting a potential protectiveness of cesarean section against impairment to the EAS. Our results do not provide significant evidence regarding the interaction effect of delivery mode and age; further investigations are needed to confirm this conclusion.
KW - Aging
KW - Delivery mode
KW - External anal sphincter
KW - Intramuscular electromyography
KW - Motor unit potential analysis
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U2 - 10.1007/s00192-019-03900-5
DO - 10.1007/s00192-019-03900-5
M3 - Article
C2 - 30863945
AN - SCOPUS:85062974451
SN - 0937-3462
JO - International Urogynecology Journal
JF - International Urogynecology Journal
ER -