Causes of constipation after surgical treatment of anorectal malformations with vestibular fistula: a clinical study of 51 children

Objective To investigate the possible causes of constipation after surgical treatment of anorectal malformations with vestibular fistula (ARMVF). Methods A total of 51 ARMVF children treated in our hospital from January 2015 to December 2017 were enrolled, and their clinical data were retrospectively analyzed. The postoperative defecation function was evaluated by Rintala rating scale, and according to the results, they were divided into constipation group and non-constipation group. Their defecation function scores, surgical methods, neuromuscular development of rectal blind, perianal muscle development, position of rectal blind, fistula diameter, and MR images of sacrococygeal region were ananlyzed and compared between the 2 groups. Results ① Postoperative defecation function: in the 48 cases with follow-up data, 43 cases (89.6%) had good defecation function and 5 cases (10.4%) had dysporia. There were 20 cases (41.7%) with constipation. Statistical difference was seen in the score between the 2 groups (P=0.014). ② There were 37 cases (77.1%) undergoing multi-stage surgery, and 11 cases (22.9%) one-stage surgery. No significant differences were found in surgical approach between 2 groups. ③Pathological results showed that concerning the development of intestinal ganglion cells, 1 case (2.0%) was normal, 44 cases (91.7%) were poorly developed, and 3 cases (6.3%) were aganglionosis. The difference in the abnormal development of intestinal ganglion cells were statistical different between the 2 groups (P=0.025). ④There were no significant differences in the diameter of fistula and the position of rectal blind between 2 groups (P=0.150, P=0.837). ⑤The development of perianal muscles and sacrococygeal region were statistically significant between 2 groups (Chi-square=6.237, P=0.044; Chi-square=5.573, P=0.018). Conclusion Abnormal development in intestinal ganglion cells of the rectum, poor development of the perianal muscles, and abnormality of the sacrococygeal region are the possible causes of constipation after surgical treatment of ARMVF. The associations of surgical approaches, diameter of fistula, position of rectal blind with postoperative constipation are not observed