Prolapse and Procidentia of Rectum and Anus

Primary Diseases of the Rectum and Anus.

These conditions obtain most frequently at the two extremes of life, infancy and senility, but have a very different causation in each. Prolapse of the bowel may be partial or complete—partial when a portion of the mucous membrane is extruded, and complete when the entire rectum appears outside the anal orifice. A predisposing cause in infants is found in the mobility of the bowel—in the fact that it and the sacrum are much less curved than in the adult, and the abdominal viscera are more voluminous: this, associated with the undeveloped state of the muscular system, causes the weight and strain to act directly and forcibly upon the sphincters, and the extrusion takes place. It is often excited by allowing children to sit for a length of time upon the chamber-vessel. It is frequently caused among children by the presence of vesical calculi, by Oxyuris vermicularis, diarrhoea, constipation, dysentery, polypi, and by the long-continued acts of coughing and crying.

In adults and the aged it may be caused by loss of tone of the anus and rectum in chronic diarrhoea and dysentery, or from the energetic action of drastic cathartics, by urinary calculi, the long-continued use of enemata, chronic cough, diarrhoea alternating with constipation, stricture of the urethra, prostatic hypertrophy, tenesmus due to the presence of polypi, and by the pressure of a pelvic tumor. It may accompany procidentia uteri and hemorrhoids. An incomplete, reducible prolapse consists of two or more overlapping plications of normal-looking mucous membrane, sensitive but painless. In these cases there is provoked a hyperplasia of much-elongated connective tissue in the submucous space which undergoes serous infiltration and causes an oedematous condition of the part. In a complete prolapse the entire rectum—all of its component layers—is protruded through the anus. In a recent case the folds of the gut are well marked, but in one where the bowel has remained in this abnormal condition for some time the submucous tissue becomes charged with inflammatory deposit which effaces the plications and causes the bowel to become pale, hard, dry, and tough; and finally pigmentation occurs and the part assumes somewhat the character of true skin. These vary greatly in size, from the slightest protrusion of mucous membrane to a tumor the size of a melon. Usually they are reduced with ease, but their reappearance is occasioned by the slightest tenesmus.

In old age the soft parts of the floor of the pelvis and the anal sphincters lose to a great extent their tone and contractile vigor, and the rectum, also participating in this change, is often unable to withstand the increased thrust of the diaphragm and the compression of the abdominal muscles during defecation; which act frequently demands more exertion on account of a tendency to constipation in advanced life.

In these long-standing cases of senile procidentia it is a matter of experience, verified by post-mortem dissection, that the fibres of the sphincters and of the levatores ani muscles are flattened, pale, and stretched beyond the possibility of contraction, while the entire perineum is in a state of atrophy.