Bowel function after surgery for anorectal malformations in patients with tethered spinal cord

Tethered spinal cord (TC) is an anomaly frequently recognized in association with anorectal malformations (ARM). However, the influence of TC on bowel function in children with ARM remains unknown. Furthermore, there are few studies that have assessed anorectal function in children with ARM and TC. The aim of this study was to evaluate anorectal function in ARM patients with TC using clinical assessment and anorectal manometry. Among 258 patients with ARM, this retrospective investigation included 35 patients who underwent spinal magnetic resonance imaging (MRI) after surgery for ARM. The patients were divided into two groups based on the presence or absence of TC, and bowel function was assessed by Kelly's clinical score and anorectal manometry. Tethered cord was found in nine of the 35 patients (26%) with ARM. Of the ARM patients, TC was noted in four of 11 (36%) with high type anomalies, one of 8 (13%) with intermediate type anomalies, two of 14 (14%) with low type anomalies, and two of two patients (100%) with cloacal anomalies. Kelly's clinical score did not significantly differ between the two groups. However, two of the nine patients with TC had poor bowel function (Kelly's score; 2-0 points). On the contrary, patients without TC did not have poor bowel function. Anorectal manometry did not show a significant difference between patients with and without TC. However, the two patients with TC who had poor bowel function by Kelly's score had low anal resting pressure, which was essential for achieving fecal continence. In conclusion, the present study showed that tethered cord was more frequently found in patients with more severe anorectal anomalies. Patients with TC were more likely to have poor bowel function, but this did not reach statistical significance.