Gluteus maximus flap transplantation for anrectal dysfunction after anorectal malformation operation

Abstract

Objective To evaluate the effect of gluteus maximus flap transplantation to reinforce levator ani for the anorectal dysfunction after previous anorectal malformation operation. Methods Twenty eight children aged 4-14 years old, including 19 boys and 9 girls, were enrolled in this study. All the children suffered from anorectal dysfunction after previous operations for congenital anal atresia. Among them, 18 patients had levator ani muscle dysfunction, while the other 10 had levator ani muscle and anal sphincter dysfunction. All subjects received examinations including pelvic floor MR, barium enema and gluteus maximus electromyography. All patients underwent gluteus maximus flap transplantation to reinforce levator ani. Colonic transit testing, anorectal pressure and defecation score were also studied to evaluate the surgical efficacy. The patients were followed up for 4-48 months, with an average of 24 months. Results Twenty six patients were followed up after surgery. Before surgery, gluteus maximus electromyography and barium enema revealed normal muscle function and bowel movement. Colonic transit testing showed outlet obstruction. Pelvic floor MR revealed levator ani muscle complex was poorly developed and asymmetric. All 28 patients' defecation function was scored as poor before operation. After surgery, 69.23％ patients achieved excellent and good defecation function. Among the patients with levator ani muscle dysfunction, 6 patients' defecation were scored excellent and 10 were good. However, among the patients with levator ani muscle and anal sphincter dysfunction, 2 patients' defecation function was scored good while the other 8 were poor. Conclusions Gluteus maximus flap transplantation to reinforce levator ani is safe and effective to treat anorectal dysfunction in patients with previous anorectal malformation operation. Key words: Anus, abnormalities; Rectum, abnormalities; Colorectal surgery