Posterior sagittal anorectoplasty.

From October 1980 to November 1981, 34 patients with anorectal anomalies have been operated upon by a sagittal midline approach. The skin incision extends from the sacrum to the perineum (ventral aspect of the anal dimple). The superficial and deep layers of the external sphincter are identified by electrostimulation and split, with the coccyx, in the midline. Ileo- and pubococcygeal portions of the levator dorsally and then the striated muscle complex of the external sphinctor, pubococcygeus and the presumed puborectalis are split ventrally to the urethra. In no cases has the ventral portion of the levators been separated from the thick ventral portion of the external sphincter, hence the term "striated muscle complex." When the terminal bowel is dilated (congenitally ectatic), the bowel is tailored prior to reconstruction of the sphinctors. The posterior sagittal approach provides an excellent exposure for evaluation and mobilization of the terminal bowel. It enables one to construct an anal canal, suture the bowel wall to the striated musculature and the mucosa to the skin, thereby reducing or avoiding the complications of prolapse and stenosis. In males with ectasia and a rectourethral fistula, transrectal closure of the mucosa at the fistula site, leaving the rectal longitudinal smooth muscle insertions on the prostatic capsule, avoids damage to the nerves and genital structures.