Voluntary anal continence after surgery for anorectal malformations

Area of Science:

• Pediatric Surgery
• Urology
• Physiology

Background:

• Anorectal malformations (ARMs) are congenital conditions requiring surgical correction.
• Assessing external sphincter muscle function is crucial for predicting continence outcomes.
• Surgical outcomes for ARMs can vary based on anomaly type and severity.

Purpose of the Study:

• To evaluate external sphincter muscle function in children post-surgical correction of anorectal malformations.
• To compare sphincter function between different types of anorectal malformations and healthy controls.
• To investigate the relationship between sphincter function and continence in pediatric patients.

Main Methods:

• Electromyography (EMG) was used to assess external sphincter muscle activity.
• Voluntary contraction pressure of the external sphincter was measured in 28 patients (aged 5-14) and 10 controls (aged 5-15).
• Patients were categorized based on high-type, low-type, or intermediate-type anorectal malformations.

Main Results:

• External sphincter function, including tonic activity and reflex responses, was compromised in patients with high-type ARM.
• Sphincter function was preserved in patients with low-type or intermediate-type ARM, comparable to controls.
• Phasic activity was present in all patient groups and controls; however, low voluntary contraction pressures (<20 cmH2O) were noted in some high-type ARM patients.

Conclusions:

• High-type anorectal malformations significantly impact external sphincter function.
• Low-type and intermediate-type ARM patients demonstrate preserved sphincter function.
• Despite functional deficits, patients with high-type ARM may achieve voluntary continence through targeted bowel training programs.