Related Experiment Video
Updated: Dec 8, 2025
Quantification of Levator Ani Hiatus Enlargement by Magnetic Resonance Imaging in Males and Females with Pelvic Organ Prolapse
Published on: April 17, 2019
Fecal Continence for Solid and Liquid Stool: The Function of the Anal-External Sphincter Continence Reflex and the
Jara E Jonker1, Monika Trzpis1, Paul M A Broens1,2
1Department of Surgery, Anorectal Physiology Laboratory, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands.
Background:
The anal-external sphincter continence reflex and the puborectal continence reflex control fecal continence by involuntary contractions of the external anal sphincter and puborectal muscle. To date it is unknown what the effect of liquid stool is on these reflexes.
Objective:
The purpose of this study was to analyze the consequence of liquid stool on the presence and function of these fecal continence reflexes.
Design:
This was a prospective, observational study.
Setting:
The study was conducted at the Anorectal Physiology Laboratory, University Medical Center Groningen.
Patients:
Forty-two healthy subjects were included.
Main Outcome Measures:
Pressure changes at the level of the external anal sphincter and the puborectal muscle during the anorectal pressure test used to measure voluntary contractions, the balloon retention test used to measure involuntary contractions mimicking solid stool, and the rectal infusion test used to investigate the effect of only water mimicking liquid stool were measured.
Results:
During the test mimicking solid stool, the pressure at the level of the external anal sphincter increased from the start to the end (132 ± 54 vs 198 ± 69 mm Hg; p < 0.001). The pressure at the level of the puborectal muscle increased simultaneously (30 ± 9 vs 176 ± 52 mm Hg; p < 0.001). After injecting water into the rectum, mimicking liquid stool, we observed immediate activation of the anal-external sphincter continence reflex (87 ± 32 vs 145 ± 36 mm Hg; p < 0.001); this was after a median 30 seconds, whereas no activation of the puborectal continence reflex appeared (26 ± 9 vs 26 ± 7 mm Hg; p = 0.655).
Limitations:
We only performed anorectal function tests mimicking 2 types of stool consistencies, namely water and solid.
Conclusions:
The anal-external sphincter continence reflex controls fecal continence of both solid and liquid stool. Contrarily, the puborectal continence reflex contributes to solid stool continence only. See Video Abstract at http://links.lww.com/DCR/B286. CONTINENCIA FECAL PARA HECES SÓLIDAS Y LÍQUIDAS: LA FUNCIÓN DEL REFLEJO DE CONTINENCIA DEL ESFÍNTER ANAL EXTERNO Y EL REFLEJO DE CONTINENCIA PUBORRECTAL: El reflejo de continencia del esfínter anal externo y el reflejo de continencia puborrectal controlan la continencia fecal mediante contracciones involuntarias del esfínter anal externo y el músculo puborrectal, respectivamente. Hasta la fecha, se desconoce cuál es el efecto de las heces líquidas en estos reflejos.Analizar las consecuencias de las heces líquidas en la presencia y función de estos reflejos de continencia fecal.Estudio prospectivo observacional.Laboratorio de F fisiología anorrectal, University Medical Center Groningen.Cuarenta y dos sujetos sanos.Los cambios de presión a nivel del esfínter anal externo y el músculo puborrectal durante la prueba de presión anorrectal utilizada para medir las contracciones voluntarias, la prueba de retención con balón utilizada para medir las contracciones involuntarias que imitan las heces sólidas, y la prueba de infusión rectal utilizada para investigar El el efecto de solo agua imitando las heces líquidas.Durante la prueba que imita las heces sólidas, la presión a nivel del esfínter anal externo aumentó desde el principio hasta el final (132 ± 54 mm Hg versus 198 ± 69 mm Hg, p <0.001). La presión a nivel del músculo puborrectal aumentó simultáneamente (30 ± 9 mm Hg versus 176 ± 52 mm Hg, p <0,001).Después de inyectar agua en el recto, imitando las heces líquidas, observamos la activación inmediata del AESCR (87 ± 32 mm Hg versus 145 ± 36 mm Hg, p <0.001), esto fue después de una mediana de 30 segundos, mientras que no hubo activación de la continencia puborrectal apareció reflejo (26 ± 9 mm Hg versus 26 ± 7 mm Hg, p = 0,655).Solo realizamos pruebas de función anorrectal que imitan dos tipos de consistencia de heces, a saber, discriminando entre a agua y sólidos.El reflejo de continencia del esfínter anal-externo controla la continencia fecal de las heces sólidas y líquidas. Por el contrario, el reflejo de continencia puborrectal contribuye solo a la continencia de heces sólidas. Consulte Video Resumen en http://links.lww.com/DCR/B286. (Traducción-Dr Adrian Ortega).
Related Concept Videos
01:26Feces Formation and Defecation
The mass peristalsis then pushes the feces into the rectum, which stretches the rectal walls to activate...
01:26The Micturition Reflex
The process begins with bladder filling, where the bladder wall stretches as urine accumulates. This stretching activates the urine storage reflex, mediated by the sacral spinal segments and the pontine storage center. Efferent sympathetic impulses stimulate the detrusor muscle to relax and the internal urethral sphincter to contract, facilitating...
01:25Assessment of the Rectum and Anus
Rectal Inspection
Begin by inspecting the perianal and anal areas for color, texture, rashes,...
01:26Muscles of the Pelvic Floor and Perineum
Perineal Layer
The perineum is a diamond-shaped area below the pelvic diaphragm, divided into an anterior urogenital triangle that contains the external genitals and a posterior anal triangle housing the anus. The urogenital...
01:21Inflammatory Bowel Disease V: Surgical Management
Here are some common surgical interventions for IBD:
01:26Physiology of the Gastrointestinal System III: Elimination