Congenital Malformations

The simplest form of congenital malformation in this region consists in an anus of insufficient size for the natural demands of the system, but in no other manner abnormal. The most frequent variety of imperforate anus is where complete occlusion is effected by the common integument or by two cutaneo-mucous flaps, which owing to defective development remain united without forming a raphé or perceptible line of union. The rectum is not involved, and when the child strains the contained meconium causes bulging of the part, which disappears under slight pressure, but reappears when again free. In other cases the occluding tissue is very firm, dense, with a disposition to pucker or form rugæ. The sphincter muscle is rarely perfect, and though an artificial anus may be made, years may elapse before the child can control the evacuation. In conjunction with an imperforate anus the colon may terminate in a cul-de-sac, or it may communicate with the urethra, the bladder, or the vagina.

An imperforate rectum has been known to discharge at the umbilicus, upon the face, under the scapula, upon the penis or the anterior part of the scrotum. Sometimes, though very rarely, a common cloaca has been found, as in fowls, common to the rectum and to the genito-urinary organs; and still more rarely the rectum has opened in abnormal sites upon the perineum and upon the buttocks.

The anus may be entirely absent. The rectum may be entirely absent or it may be incomplete, terminating at various distances from the anus. These malformations of the bowel may be associated with a perfect anus, or with any of its imperforate forms, or with a fecal fistula. In occlusion of the rectum the offending structure is in some cases a hymen-like fold of mucous membrane, which, during straining, can be recognized by the finger as a fluctuating protrusion; while in others it consists of a mass of dense fibrous tissue which extends upward from an inch to an inch and a half: in the former there is always found a normal anus; in the latter there is either no trace of anus or one in a more or less rudimentary state. In those cases where the rectum is entirely absent the intestine terminates either in a cul-de-sac or a fecal fistula; very rarely the rectum is replaced by a fibro-ligamentous cord or band which springs from the colon, and, descending toward the bladder, blends with the connective tissue of the part. In the latter the pelvis is always in an imperfect state of development, being much contracted in its lower diameters, and the anus is absent; and Rokitansky and Curling lay stress upon the non-development of the pelvis as a diagnostic guide in determining the absence of the rectum. The passage of a sound into the bladder or vagina is a procedure of some diagnostic value, as if its point impinges directly against the sacrum it may be presumed that no rectum exists. If the malformation is of such a character that the fecal matter can find no exit, a train of symptoms ensues analogous to those seen in the adult affected with intestinal obstruction: the infant cries and is constantly restless, refuses food, vomits, the abdomen distends, and death speedily ensues. A remarkable exception to this rule was the case mentioned by Bodenhamer of a child with absence of the rectum who was not operated on until three months after birth, and who was apparently in perfect health. At the operation the intestine was found three inches from the surface, and the child made a good recovery.

Although the statistics of this class of malformations are somewhat contradictory and confusing, it is safe to state that more male than female children are so afflicted.

The prognosis in the large majority of these cases is grave, for unless the operator can see or feel the fluctuating protrusion, or can recognize it after a very slight exploratory incision, he is working totally in the dark and in close proximity to the peritoneum. Hemorrhage, peritonitis, pelvic cellulitis, and septicæmia diminish the chances for recovery. Indeed, the majority of these cases are scarcely amenable to surgical treatment.