Three-flap anoplasty for imperforate anus: results for primary procedure or for redoes

Three-flap anoplasty was first described in 1987 by Yazbeck for the treatment of rectal prolapse after pull-through operations for imperforate anus, and in 1992 in a case of anterior perineal approach. It is intended to reproduce the normal anatomy of a sensitive anal canal. The purpose of this study is to evaluate 14 children (9 boys and 5 girls) operated for imperforate anus.

Eleven children had an intermediate or high imperforate anus and 3 had a low imperforate anus. Nine were operated for the first time with a three-flap anoplasty (GrA), and 5 were reoperated with this technique because of fecal incontinence and/or rectal prolapse (GrB). Seven patients had associated malformations: one Hirschsprung's disease, one cloacal defect with renal insufficiency, three complex caudal malformations with tethered cord, one Down syndrome, and two psychological and psychomotor troubles. The patients (average age = 6 years) have been evaluated every year since 1997, with a questionnaire based on a clinical score validated with 30 healthy children, used as a control group. Ten anal manometries were carried out.

In 1998, the GrA score was 16.1 (control = 22.5) and the GrB score was 11.5 (p = 0.25). In 1999, GrA and GrB score were approximately the same. The score of those without associated anomalies was 19.6 whereas the score of the children with other malformations or anomalies was 10 (p = 0.02). Anal manometry is almost normal in patients with low or intermediate imperforate anus (rectoanal relaxation reflex for 10 cm H2O, and basal resting pressure more than 40 cm H2O). Even though anal manometry is subnormal in patients with Down syndrome or psychomotor troubles, the clinical score remains low (score = 10). In cases of complex caudal malformations or high imperforate anus, the results of anal manometry and clinical score are bad (score 9.7).

The three-flap anoplasty can be carried out in newborns without colostomy and often represents the only possible surgical approach to avoid a laparotomy. This plasty, proposed secondarily to correct a defect of continence, can be performed without colostomy, with satisfactory results.