It is believed by some surgeons that these membranous valves sometimes become so thickened as to form an obstruction to the passage of feces. The writer has seen no cases of this sort, although he has carefully looked for them in hundreds of cases.
Failure of the anus to relax when the colon contracts interferes seriously with defecation, and may prevent movement of the bowels. This may result from various causes, as a weak stimulus from the defecation center, or unduly contracted anal muscles. This point will be considered further in another connection.
Virchow was the first to observe the conditions to which Mr. Lane, an eminent London surgeon, first applied the term "kinks," but his observations received little attention until within recent years. Mr. Lane has shown the important relation which they bear to the functions of the colon and to general conditions of the body arising from autointoxication.
The narrowing which occurs from folding of the bowel or compression by bands, is usually the result of adhesions. The obstruction thus produced causes stasis, or stagnation, and increase of putrefactive changes in the foodstuffs, with infections of the intestine, from which come still further thickening and narrowing of the bowel, and so continual increase of delay and of constipation.
The pelvic loop sometimes becomes so much elongated that when it is emptied and falls over backward into the pelvis it makes several folds upon itself. If adhesions form an extension of infection through the wall to the outer surface, as they sometimes do from pericolitis, "kinks" are developed which may require surgical means of relief.
Within the last dozen years there has been much discussion in medical circles about a "kink" located at the lower end of the small intestine within a few inches of the ileocecal valve. Lane, of London, has attributed to these adhesions of the terminal ileum stasis or stagnation of materials in the ileum, and most of the disease conditions which develop in the stomach, liver, duodenum, gall-bladder and pancreas.
Recent observations made at the operating table by the writer and others, clearly show, however, that "Lane's Kink" is practically always associated with incompetency of the ileocecal valve. It seems most probable that adhesions of the lower end of the ileum are the result of inflammation caused by the backing up of fecal matters into the small intestine through the open valve. It has also been observed that these "ileal kinks," first mentioned by Lane, are seldom obstructive, the real cause of the delay in the small intestine associated with "kinks" being incompetency of the ileocecal valve, which also is the cause of the "kink."
Fecal accumulations in the rectum, and in some casespossibly also accumulations in the pelvic colon and in the caecum, may give rise to various reflex pains on account of pressure. Fain in the buttocks and the back of the thigh, and a dull pain in the region of the sacrum is often due to the pressure of fecal matters in the rectum. Neuralgia of the testicles and of the ovaries, and dysmenorrhea in young women, is often traceable to this cause. Abnormal sexual excitability, especially during sleep, is also sometimes traceable to accumulations in the rectum. Itching about the anus, is often caused by the pressure of a small amount of fecal matter in the anal canal, disappearing at once when the feces are removed. Hemorrhoids may be caused by the pressure of fecal matters upon the hemorrhoidal veins; and varicocele, if not produced, is certainly aggravated by accumulations of fecal matters in the iliac colon.
Headache and sometimes vertigo and a sensation of exhaustion and depression are symptoms commonly experienced by persons suffering from cumulative constipation. These symptoms may be the result of reflex action, which seems most probable, or they may be in whole or in part the result of chronic poisoning due to the absorption of long retained fecal matters. The fact that the symptoms disappear almost immediately when the bowel is emptied by an enema, does not necessarily indicate that the act is reflex. Effects due to autointoxication are the result of over-saturation of the blood with poisons derived from the bowel contents. When, by removal of the source of the poisons, the intake ceases, the liver and kidneys quickly clear the blood of the subtle intoxicants, and the nerve disturbance ceases.
The violent straining occasioned by the presence of dry and hard feces in the rectum and lower colon is not merely an inconvenience, but often results in serious and sometimes fatal injury.
One of the most common results of straining at stool, especially when prolonged or repeated several times daily, is hemorrhoids, or piles. These are excrescences which form just in the anus, or at its lower edge. The accumulation of fecal matters in the rectum obstructs the flow of blood in the veins which have their origin at this point, and in straining these veins become greatly distended with blood; their walls become thickened, forming irregular masses which are usually forced out when the bowels move. As the result of the straining, and often as the result of the use of rough toilet paper, the delicate mucous membrane becomes abraded or cracked, infection occurs, and the hemorrhoids become 'inflamed and swollen causing still further thickening. Thus the hemorrhoids gradually increase in size, until they may become so large that the anal sphincters are over-stretched and become relaxed, and in time the rectum may be pushed outside whenever the bowels move. Prolapse of the rectum is most likely to occur in children and emaciated adults.
In persons suffering from arteriosclerosis or degeneration of the blood-vessels, especially aged persons, straining at stool may cause rupture of a blood vessel and sudden death. In angina pectoris a spasm may result from straining at stool, sudden death having been known to occur in cases in which the heart was very feeble.