A Single-center Retrospective Study of Laparoscopic-Assisted Megarectosigmoid Resection with Anal Reconstruction: Long-term Functional Outcomes and Prognostic Factors

Background Megarectosigmoid (MRS), a complication following anorectal malformation (ARM) repair, impairs pediatric quality of life. Current treatments lack consensus due to variable efficacy. Objective To evaluate the long-term outcome of laparoscopic-assisted MRS resection with anal reconstruction (LAMR-AR) and prognostic factors in refractory MRS post-ARM repair. Methods A retrospective cohort analyzed 49 pediatric MRS patients undergoing LAMR-AR. Clinical data included imaging and surgical parameters. Patients were stratified by anal morphology: primary (normal anatomy) vs secondary (stenosis/ectopic anus). Functional outcomes were assessed via Rintala scores (R-score) and Krickenbeck criteria for soiling/constipation. Results This study enrolled a cohort of 49 pediatric patients (28 males, 21 females) with a median age of 2.75 years (interquartile range [IQR]: 1.42-3 years). Postoperatively, in primary group, constipation decreased from 92.9%(26/28 grade3:26) to 7.1%(2/28 grade2:1 grade3:1), while soiling increased from 3.6%(1/28 grade3:1) to 57.1%(16/28 grade1:9 grade2:7). As for the secondary group, constipation decreased from 85.7%(18/21 grade3:18) to 23.8%(5/21 grade2:4 grade3:1) and soiling increased from 4.8%(1/21 grade3:1) to 71.4%(15/21 grade1:2 grade2:9 grade3:4).Secondary cases showed higher complications after ARM repair rates (32.1% vs 14.3%, p =  0.04) and lower R-scores (2.8 vs 3.4, p  = 0.012). Pelvic muscle abnormalities correlated with poorer R-scores ( p =  0.02). R-score improvement positively correlated with age (r = 0.306, p =  0.032). Conclusion The long-term outcomes of LAMR-AR demonstrated a better outcome in primary group than secondary group. Pelvic muscle abnormalities predict poorer bowel function after LAMR-AR, while bowel function improvement correlates with patient’s age.