Determination of the anal position in newborns and in children with chronic constipation: comparative study in two European healthcare centres

• Published in: Pediatric surgery international Vol. 27; no. 10; pp. 1111 - 1115
• Main Authors: Núñez-Ramos, R., Fabbro, M. A., González-Velasco, M., Núñez Núñez, R., Romanato, B., Vecchiato, L., D’Agostino, S., Blesa Sánchez, E.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer-Verlag 01.10.2011; Springer Nature B.V
• Subjects: Anal Canal - abnormalities; Child; Child, Preschool; Chronic Disease; Constipation - epidemiology; Constipation - etiology; Female; Humans; Incidence; Infant; Infant, Newborn; Italy - epidemiology; Male; Medicine; Medicine & Public Health; Original Article; Pediatric Surgery; Pediatrics; Prospective Studies; Sex Distribution; Spain - epidemiology; Surgery; Italy; Spain; Anterior displacement of the anus; Anterior ectopic anus; Chronic constipation; Anal position index; Anal-genital index
• ISSN: 0179-0358; 1437-9813
• DOI: 10.1007/s00383-011-2914-4

Introduction The objective of this study was to determine the normal anal position index (API) in neonates and in a group of older children with chronic constipation, and to identify the incidence of anterior ectopic anus (AEA) in the two groups. Materials and methods A prospective random study was carried out in two European hospitals determining the API in 1,012 neonates (529 in Group A, and 483 in Group B) and in 64 children suffering chronic constipation of ages between 3 months and 12 years (Group C). The API is defined as the ratio between the fourchette-anal and fourchette-coccygeal distances in girls and the scroto-anal and scroto-coccygeal distances in boys. The gestational age, weight, meconium evacuation and anal calibre were recorded in Groups A and B, and age, sex, and API in Group C. Statistical comparisons were made using Student’s t test and Welch’s t test for independent sample groups. Results The mean API in Group A was 0.53 ± 0.06 in males and 0.40 ± 0.05 in females, and in Group B 0.51 ± 0.06 in males and 0.39 ± 0.08 in females, with significant differences between the sexes ( p  < 0.0001) in both groups; 1.7% of the neonates in Group A and 2.4% of Group B presented AEA. 4/13 newborns females with AEA presented with severe constipation during their first months of life. For the 64 patients in Group C: 59.3% were female; the mean API was 0.47 ± 0.1 in males and 0.36 ± 0.1 in females ( p  < 0.0001). The incidence of AEA was 47% in females and 35% in males. Conclusions In the neonates (Groups A and B), the position of the anus in the perineum was more anterior in females than in males ( p  < 0.0001); 31% of the newborns females with AEA presented with constipation in their first months of life. In the Group C patients, there was a high incidence of AEA, especially in the females, and we consider it to be the probable cause of this defecation disorder.