Chapter II: Part 2

Should the operator deviate from the described directions for the manipulation of his fingers and so twist his hands as to divulse the anus in the anteroposterior direction instead of laterally, he invites defeat upon himself, for in the male the fixation of the perineum and the immobility of the coccyx interfere with the requisite dilatation; while, in the female, the extreme mobility of the perineum and particularly the backward displaceability of the coccyx will allow such traction to be made upon the levatores ani as to pull their inner fibers parallel and almost together, and, in consequence, the wider the female’s anus be opened anteroposteriorly the closer is it made to contract laterally to rob one of his view.

INSTRUMENTAL INSPECTION.

Certain paraphernalia and much practice in their use are necessary for rapid, complete and painless inspection of the rectum.

The _chair_ which is shown in the illustrations was designed by me to facilitate the placing of the patient in a new posture, which is equivalent to the knee-chest posture.[13]

Fig. 3 exhibits the chair and the attached illumination-apparatus in the first position to receive the patient. Fig. 4 shows the chair and illumination attachment in the second position, and Fig. 5 shows the chair and illumination-apparatus in the position for the third step in the procedure. Fig. 3 shows, also, hanging from the head of the chair, a small pillow and the shoulder-suspender.

The _anoscope_ (Fig. 6) consists of a short cylindric tube open at the ends. It is two inches (5.08 cm.) in length and seven-eighths of an inch (2.22 cm.) in diameter. The proximal end is provided with a trumpet-shaped expansion and a strong handle. The distinctive feature of the anoscope is the peculiar form of its obturator (Fig. 7), which has a capacity for a multiplicity of uses.

The _obturator_ consists of a hard-rubber cylinder, in the middle of which is fixed a brass tube for the purposes of irrigation. Its surface is fluted in such a manner that it may be made to lock in any of several positions upon a tubercle within the cylinder. These flutes also provide for escape from the rectum of fluids and gases under certain conditions. The contracted neck near the distal end of the obturator provides a cup to facilitate the application of ointments to certain rectal areas.

The contracted neck is a feature which contributes to the instrument’s usefulness as a means for irrigation, providing in the one case a self-retaining direct-flow irrigator, and in the other case when locked in the position shown in Fig. 9, an unobstructed two-way irrigator. Platinum pins connect the centrally-placed brass tube with the surface of the neck of the obturator, which makes the instrument an anal electrode.

The _proctoscope_ (Fig. 10) is of the same diameter as the anoscope, and is four inches (10.16 cm.) in length, which, because of the displaceability of the pelvic floor is usually of sufficient length to reach as high as the promontory of the sacrum, except in some especial instances, the management of which exceptions will be treated of in another place.

_Special preliminary preparation_ of the patient is ordinarily not required, as the usual condition of the rectum is that of emptiness. In some cases, however, it facilitates the inspection if the patient employs rectal lavage an hour before the examination. This injection should not consist of more than one pint of fluid. The excess of this might be accidentally dejected from the sigmoid and obscure the field during examination. The bladder should be emptied, since its distention would necessarily interfere with the accuracy of the examination.

THE TECHNIC.

_Step 1._--The patient should be required to sit on the operating-chair with his body turned to the left, facing the knee-board. The right knee should be crossed over the left knee, the left arm should embrace the right border of the chair-back, or it may be folded at the side as for Sims’ posture. The small pillow should be held in the patient’s right hand and against and upon his left shoulder (Fig. 13).

_Step 2_ consists in shifting the chair to the horizontal position shown in Figs. 14 and 4, and in adjusting the light-fixture. This movement brings the patient into Sims’ semiprone-semiflexed posture, without requiring any movement whatever on the part of the patient after he is properly seated. In this posture, the external anus and fixed rectum are to be examined.

(_a_) Digital examination and ocular inspection should now be made of the anal verge, the external anus, and superficial ischiorectal space, at a moment when the patient is relaxed, and, again, when he is bearing down.

(_b_) Digital examination of the fixed or anal rectum, also, should be made preliminary to the introduction of the anoscope.

(_c_) The anoscope should be gently pressed into the anus in the direction of its axis till the sphincters relax to receive it. The introduction of an instrument into the rectum may be much facilitated by placing its lubricated end against the ectal sphincter and requiring the patient to bear down; bearing down expands the ectal sphincters, relaxes the levator ani, thins the pelvic floor, or shortens the fixed rectum, and presses the ental sphincter over the instrument--in other words, the patient’s anus is made to climb down upon the speculum. After the introduction of the anoscope, its obturator should be removed, and the inspection made. These observations should be made coincident with the withdrawal of the anoscope. In cases of extremely sensitive ani, a skillfully put hypodermic injection into the sphincters of 10 or 20 minims of ⅒ of 1% solution of cocain may render anoscopy painless.

A desire for precision requires that _lesions of the fixed or anal rectum_ should be noted as occupying a given quadrant, and as situated at a given zone, _e.g._, a circumscribed disease may be described as situated at the ental sphincter zone, and in the left lateral quadrant.

_Step 3_ (_a_) requires that the shoulder-suspender should be placed and fixed to the chair, as shown in Figs. 5 and 16, that the knees be drawn up, so that the thighs are at a right angle to the length of the chair-top, and that the chair should be tilted to put the patient in the new posture shown in Fig. 16. The leg foot-board should now be lowered, and the operator’s stool placed in convenient position.

The illumination-apparatus should now be adjusted, as shown in the illustrations. In this new posture, which is equivalent to the knee-chest posture, the abdominal rectum is to be examined.

(_b_) Introduction of the proctoscope requires supported eversion of the buttocks and steady gentle pressure of the well-lubricated instrument upon the anus and in the direction of the umbilicus, until the sphincters are felt to yield, or the patient may be required to bear down to take the speculum; as the instrument enters the inflatable movable rectum, it should be pointed toward the promontory of the sacrum, and subsequently into the sacral hollow. The withdrawal of the obturator is followed by atmospheric inflation of the rectum.

(_c_) The operator should observe the degree of rectal distention, the situation and number of the rectal valves, their propinquity to one another when passive, and the relation of one valve to another at the time of the patient’s bearing down. Under pressure of the proctoscope if possible, or the hook if necessary, each valve should be effaced or displaced, and in regular order each of the rectal chambers should be carefully inspected. A proctoscopic mirror may be necessary for viewing the supravalvular surfaces (Fig. 18). The examination being finished:

_Step 4._--The proctoscope should be withdrawn, the illumination-apparatus fixed in the first position, the leg foot-board lifted to its place, the lever extended, the crank turned and the chair carried back to the horizontal and upright positions, and thus the passive patient may be returned to his feet by the execution in the reverse order of the several steps described.

This method of inspection does not subject the patient to struggle, strain or embarrassment.

Observation by this method has taught me that in nearly all cases of disease at the anus there is congestion or inflammation of the rectal mucous membrane.

Those cases in which there is no apparent lesion at the anus, and which are in a perfunctory way sometimes declared catarrh of the rectum, will at once have the real condition, such as a high up rectal polypus, congenital or organic stricture or ulceration, positively diagnosed, and will be made accessible for intelligent treatment.

New growths and ulcerations may be seen and by means of a long-handled curet scrapings made in order that the microscopist may determine their exact character.

Stricture of the rectum need no longer be regarded as of only doubtful presence, and this method proves positively, even to the casual observer, how fallacious is the method of rectal sounding usually employed for the diagnosis of stricture. I have repeatedly proved to visitors how easy it is for an entering or returning bulb-sound to be caught and held by the rectal valves,[14] and thereby yielding signs generally considered diagnostic of organic stricture of the rectum.

Vesicorectal, vaginorectal and other deep fistulas are often apparent at a glance, but in any case may be discovered by the use of the proctoscopic mirror.

If this method of ocular examination be practised, I am convinced there need be no longer any excuse for calling an undiagnosed disease of the rectum obscure disease, and whatever the disease present this method makes it susceptible of demonstration by the proctologist to the attending physician. There is no necessity that a diagnosis be taken on faith.

TOPOGRAPHIC ANATOMY.

A close study of the lesions of the rectum and their manifestations and some experience in discussion of these subjects have convinced me of the necessity of methods of greater accuracy than those generally employed in designating the precise situation of a pathologic feature in this organ. Mensural methods of designating the situation of strictures in the rectum are of no surgical value.

The manner of the application of the details in a given method of treatment for a disease situated in the fixed or anal portion of the rectum should differ essentially from that employed in the application of the same principles of treatment to a similar disease situated in the movable abdominal rectum; and the application of the details of a given kind of treatment should differ, too, according to the situation of the disease at one point or another in the circumference of the rectum. The prognosis as well as the treatment of rectal disease is determined not only by the pathologic character of the lesion, but also by its anatomic situation. “Two inches up,” or “one and a half inches from the anus,”[15] if one were positively sure of the precise location referred to as the anus, would point to very different anatomic parts, whether the subject were male or female, and whether young or old, and whether thin or stout.

The rectum, the terminal 8 or 10 inches (20.32 or 25.40 cm.) approximately of the intestine, presents an upper abdominal and essentially movable portion, which is about three-fourths the length of the entire rectum, and a lower coccygeoischioperineal and essentially fixed anal portion, which is about one-fourth the length of the rectum. The upper half of the movable rectum is, in the majority of adult persons, completely invested with peritoneum, which sometimes provides this portion with a mesentery. The lower half of the movable rectum begins at a point about the upper border of the second sacral bone, and is not completely invested with peritoneum; the peritoneum is reflected from the sides of the rectum toward the lateral masses of the sacrum, so that the posterior wall of this part is not covered by peritoneum. The movable rectum begins opposite the sacroiliac synchondrosis. If a subject lies in the dorsal posture, and if the abdomen be normal, the upper end of the rectum will lie opposite the left sacroiliac synchondrosis. If the patient is inverted to the knee-chest posture or its equivalent, and if the abdomen is normal, the upper end of the rectum, if distended, is usually found nearer the right sacroiliac synchondrosis. The movable abdominal rectum terminates at the levator ani muscle.

The fixed anal rectum begins at the levator ani and coccygeus muscles. The levator ani has its origin at the sides of the bodies of the pubic bones, the coccygeus at the spines of the ischii, and the levator ani has additional origin from the fascia and bony parts on a line between these two points. The fibers of these muscles are directed downward and inward to the fixed anal rectum; many fibers are blended into the contiguous structures of the pelvic floor. The coccygeolevator muscles may be compared to an opened slat-fan, the apex having its place at the anus, and its long border representing the line of origin of the muscles, Fig. 19. The ental sphincter ani muscle, situated a few lines below the levator ani, is made up of an aggregation of the fibers of the circular non-striated muscular intestinal coat, Fig. 20. The ectal sphincter ani striated muscle is situated immediately beneath the external skin. It serves the present occasion to describe the ectal sphincter of the male as a loop of muscle thrown about the terminal end of the rectum and hitched to the terminal bone of the coccyx, and in the female as a longer loop of muscle twisted upon itself so as to make a tandem-loop, which, in the form of the figure eight (8), is thrown about the vagina and terminal end of the rectum.

In the passive subject the finger discovers the ectal sphincter as a broad, relaxed band of muscle situated beneath the external skin and surrounding the infra-anal depression. In action the ectal sphincter is contracted and is retracted from beneath the external skin to a point beneath the mixed mucocutaneous integument. In such a state of ectal sphincter contraction the fixed portion of the rectum is lengthened, or in other words, the pelvic floor is deepened one-half inch (1.27 cm.), approximately. The finger progressing, it engages the tonicly contracted ental sphincter muscle which the delicate touch discovers as vibratory in its grasp of the finger, presenting to the touch the sense of a sharp rigid ring, and again as a flat band snugly applied about the finger. A few lines above the ental sphincter the finger discovers the upper limits of the fixed or anal portion of the rectum surrounded by the somewhat V- or U-shaped borders of the levator ani muscle; the anterior quadrant is not encircled by the levator ani. The fixed portion of the rectum presents, then, to the touch, three landmarks: the usually relaxed ectal sphincter, the usually contracted ental sphincter, and the levator ani muscles. The normal levator ani muscle can not by the contraction of its fibers close the upper end of the fixed rectum. It is possible, however, for the patient to contract his levator upon the finger of the examiner to quite an appreciable degree, a fact which led Mr. Harrison Cripps to state that the levator ani can close the upper end of the fixed rectum. If a tubular speculum of seven-eighths of an inch (2.22 cm.) diameter be introduced through the fixed rectum and then withdrawn through the levator ani to a point above the ental sphincter and the patient be directed to contract the muscles of the pelvic floor, it may be observed that the axis of the fixed rectum is directed more forward at its upper end, and that the depression between the levatores ani is partially encroached upon by the levator fibers but is in no sense effaced; hence, we must recognize that the lower fixed portion of the rectum presents a canal of an hour-glass form, expanded above as a concavity between the borders of the levatores ani, narrowed at its middle part by the contracted ental sphincter, and expanded below where it is surrounded by the relaxed ectal sphincter muscle.

In the same subject the length of the fixed anal rectum is variable with a state of activity or passivity, and in a state of activity there are variations in its length of at least one inch (2.54 cm.) between a contracted, uplifted pelvic floor and that of a depressed floor with anal eversion; both of which conditions may rapidly follow one upon the other while the examiner’s finger is engaged in diagnosis. Again, variations in depth of the fixed anal rectum are quite noticeably regulated by the size of the finger introduced. The thumb may find a fixed anal rectum of two inches (5.08 cm.) in depth, while the little finger discovers it but a little more than an inch (2.54 cm.). Because of the bony confines to the tissues of the ischiorectal space, displacement of its structures to open the anus must occur in the vertical direction, the larger the finger the greater the displacement upward.

Passing the finger beyond the borders of the levator ani, the distal phalanx enters the movable or abdominal rectum, where it may be hooked over the pelvic floor. In some instances, if the finger be directed backward and crowded with a boring maneuver through the loose folds of the movable rectum, and provided the folded knuckles displace upward the pelvic floor, the finger may be made to engage the lowermost of the rectal valves, which will contract about the finger with a rhythmic action and mislead the uninformed, inexperienced and undiscriminating explorer to think that he is but now encountering the ental sphincter muscle, or, perhaps, that he has discovered a stricture--the phantom stricture? In the passive rectum, this valve is usually about three inches (7.62 cm.) above the lower border of the ental sphincter muscle. The great range of mobility of the pelvic diaphragm permits a finger of two inches (5.08 cm.) length to be hooked over a valve which under some circumstances may be an inch and a half (3.81 cm.) beyond its reach.

The pelvic floor in the infant is often less than one-half inch (1.27 cm.) in depth. The depth of the pelvic floor in the adult, from the lower border of the relaxed ectal sphincter ani muscle to the levator ani muscle, is extremely variable. In the aged male, because of senile enlargement of the prostate, the fixed rectum may seem to be three inches (7.62 cm.) in depth. In the aged female, because of senile atrophy of the generative organs and contiguous structures, the pelvic floor may be much less than an inch (2.54 cm.) in depth. In the adipose and in emaciated subjects because of the character of the tissues occupying the ischiorectal space, there are the greatest variations in the depth of the pelvic floor. Hence, it is obvious that the palpable muscular landmarks of the fixed rectum are situated at variable positions in the different sexes, and that the length of the fixed rectum is changed in the same person at different periods of life and in differing conditions of flesh.

The visible topographic features of the fixed rectum are several, and under the influence of disease may become somewhat changed in appearance and situation. In the male they are readily discoverable by putting the subject in the dorsal posture, separating the nates with the hands and placing the thumbs on bits of dry cotton to prevent their slipping just exterior to the anus. Simultaneously to the patient’s bearing-down impulse the thumbs may be used to evert the anal mucous membrane. The anterior and posterior borders of the anus may in a measure be everted by a somewhat similar manipulation. In the female the visible landmarks of this region may be inspected by entering the finger into the vagina and placing the thumb over the perineum; the former is to push the rectum down while the thumb draws the external skin forward over the perineum. The posterior segment may be exposed by pushing the post anal skin toward the coccyx; the lateral segments may be exposed with the finger and thumb of the left hand while the right hand keeps up the initial pressure. Marked pigmentation of the anal skin is observable in a circumscribed area about the anus; beneath this area of darkened skin, intimately attached to the skin, lies the surgically unappreciated corrugator cutis ani. Within the borders of the everted anus the complexion fades to a light gray, within which zone is sometimes noticeable the distinctly lighter zone known as Hilton’s white line. Above, is noticeable an undulating zone of deeply red mucous membrane the lower border of which has been given the name of _linea dentata_ (Stroud). Between the linea dentata and the white line is a zone occupied by several pyramidal elevations about half an inch (1.27 cm.) in length, to which has been given the names: columns of Morganni and pecten of Stroud. Their bases are of a somewhat purple reddish color. Toward their apices they may pale and terminate in projecting white eminences. The bases of these pyramids, which, I believe, may without impropriety be called anal pilasters, are extremely vascular and their structure partakes somewhat of the character of erectile tissue. The apex contains a nerve end-bulb. Under the influence of disease the color of these bodies is changed. Their antemortem and postmortem appearance is quite different. There are usually present in each anus from four to eight of these bodies. Between these projections and at their lower borders, sometimes, there is discoverable a thin fold of membrane. The saccule which it, together with the anal wall and pilasters on either side, forms, has been known as the saccule Horneri, pocket of Physic, and anal pocket, sometimes inaptly called rectal pocket. Its cavity is about the size of a split pea. The three typic visible topographic features of the fixed rectum, then, are the white line of Hilton, the pecten of Stroud, or anal pilasters, and the linea dentata.

The mucocutaneous membrane of which these visible landmarks are a part, rests upon a quantity of loose connective tissue, which permits of a great range of mobility of these features independent of movement of the structures constituting the palpable landmarks of the fixed or anal rectum.

THE RECTAL VALVE.

That the rectal valve constitutes the most hypsometric of the topographic features of the movable abdominal rectum, is conclusively proven by the photographic pictures. The specimens from which the photographs were taken were prepared by a method consisting in fixing the cadaver in the knee-chest posture and pouring melted paraffin into the atmospherically inflated rectum; when the wax had sufficiently hardened the gut was carefully removed, for a few weeks immersed in alcohol and subsequently dried, varnished, and finally dried and cut into longitudinal, shell-like halves. A comparative study of the photographs of the rectal interiors discovers the fact that _the prominence of the rectal valve is increased with the degree of distention of the rectum_.

The accompanying drawing was made from a microscopic section taken from the middle of the lower valve of an adult specimen. In the illustration, Fig. 33, it is shown magnified 5 diameters. Beneath the mucosa is noticeable the heavy layer of fibrous tissue which gradually diminishes till it is lost at the valve base. Bundles of circular muscular fibers are seen in the middle of the valve. At its base are seen arteries and veins for its special nutrition. This structural arrangement makes this organ the typic anatomic valve. The evidence of the fibrous tissue in the valve is an original contribution to our knowledge of this subject.

The attached border of each valve spans a little more than half the circumference of the rectum, and its free border projects half across the diameter of the inflated rectum. Each valvular partition projects at nearly a right angle to the wall of the compartment below it and terminates in a sharply defined free border. The free margin of the structure is slightly concave in form and is directed a little obliquely. In life it is noticeable that the free border of the valve is less elastic than the main wall of the valve. The latter will yield to a modicum of traction without disturbing its free border, while traction applied at the margin may at once disturb the entire circumference of the gut at that point. The rectal wall opposite the valve is usually concave. The aperture thus formed between two rectal compartments is irregularly elliptic; it may be called the valve-strait. Usually the greatest diameter of a rectal compartment is directed laterally or else obliquely; it is almost never parallel to the direction of the sacrum. Thus, what has been heretofore considered a cavernous ampulla is seen to be divided into several chambers. There are as many chambers in the rectum as there are rectal valves. The number of rectal valves is variable. Some subjects have but two, others have four, but 90% of persons possess three. The uppermost valve is invariably situated at the juncture of the rectum and the sigmoid flexure, which valve is invariably situated on the left, the next lower is on the right wall, and the lowermost is on the left. The positions of the lower two valves are sometimes anterior and posterior.

The specimen shown in Fig. 30 exhibits the rectum naturally distended with feces. It was found in a deceased member of the demimonde who had been habituated to opium indulgence. She was forty years of age and of robust stature. On opening the abdomen the colon was discovered loaded with a collection of scybalous feces, and the upper chamber of the rectum was partially occupied with a similar deposit. The abdomen was then opened through the pubes and perineum down to the coccyx. The genitourinary organs and contiguous structures were removed, the symphisis forcibly separated and the exposed sigmoid flexure and rectum were photographed as shown in Fig. 29. The sigmoid and rectum were carefully removed and immersed in alcohol. After a fortnight the gut was divided into anterior and posterior halves, as shown in Fig. 30.

It must be readily seen that the new methods of rectal inflation for rectal inspection and the cast method of dissection, which have determined our newer ideas of the topography of this part, justify that the lowermost chamber be considered the first rectal chamber; the cavernous area beyond the first valve and below the second should be called the second chamber; and the upper chamber the third or perhaps fourth, according to the number of valves. The ancient arbitrary division of the rectum by the anatomists into upper first, middle second and lower third parts should be abandoned because such a method is inaccurate and has no surgical significance. As the arrangement of the fibers of the muscular coats of the abdominal rectum and the attachments of the abdominal rectum provide for extension and contraction of the gut on its axis, as well as expansion of the diameter of the organ, it is obvious that there must be in the same individual a great variation in the distance of any given valve from the levator ani with the variable normal states of the organ. The normal range of movement upward and downward of a given valve is from two to three inches (5.08 to 7.62 cm.).

A discriminating study of the diseases of the rectum requires an arbitrary division of the organ into several quadrants.

Regard for the conveniences of scientific description and considerations of technic and of anatomy justify that the fixed anal rectum be called _the anus_, and that the movable abdominal rectum be called _the rectum_. The former is bounded above by the levator ani and below by the ectal sphincter muscle.

From this survey of the topography of the anus and rectum and consideration of the arrangement of the contiguous structures the following salient aphorisms may be deduced:

1. In treating lesions on a level with the sphincter muscles the operator should beware of dividing these structures through the anterior quadrant. In the male the ectal sphincter terminates in the tendinous raphe in common with the transversus perinei. Contraction of the transversus perinei will separate the cut fibers of the ectal sphincter and defeat the desired subsequent union of this muscle. If an incision be carried forward or forward and laterally into the transversus perinei the perineal fascia which doubles over this muscle will be opened and the perineum and peri-urethral structures will be made accessible to infection from the anus and ischiorectal regions. In the female, to carry an incision forward through the anterior quadrant would be unsurgical because the peculiar arrangement of the fibers of the ectal sphincter ani and sphincter vaginae and their relation with the transversus perinei would perhaps conspire to produce vulvoanal or rectovaginal fistulas.

2. A stricture located at the upper end of the fixed rectum and situated in the anal fascia, in the pelvic fascia, or in the fibers of the levator ani muscle, should not be cut in the anterior quadrant nor in the posterior quadrant, but in one or the other, or both, lateral quadrants. An incision through the anterior quadrant on the plane of the levator ani muscle would divide none of its fibers because there are none there and would endanger the urinary organs and vagina in the male and female respectively. An incision made into the posterior quadrant on this plane would fail to increase the diameter of the rectum for the reason that contraction of the fibers of the levator ani would hold in coaptation the lips of the wound in such a manner as to early reestablish the stricture. A skilfully made incision in the lateral quadrants in this region will not endanger the peritoneum. A possible hemorrhage may be readily avoided by digitally ascertaining the situation of the middle hemorrhoidal arteries. And because of the direction of the fibers of the levator muscle a short lateral incision will effectually increase the diameter of the part.

3. The rectal valve must be reckoned with in studying the strictures of the movable abdominal rectum. Linear posterior proctotomy, because of the relation of the peritoneum to the posterior wall of the lower part of the movable rectum, is eminently safe, but will be efficacious only in some special instances--those instances in which the rectal valve involved is posteriorly situated. Semilunar (annular) strictures may be situated at any point in the circumference of the movable rectum, for they are built on the foundations supplied by the rectal valves, and may be safely cut through to the depth of a quarter of an inch (.63 cm.), provided the surgeon be equipped with the proper instruments and provided the rectum be maintained in a state of atmospheric inflation at the time of the operation.

The studies of the topography of the human rectum made in this research employed more than 50 autopsies, on subjects of all ages, and physical examinations of many hundred living persons, and the facts which are set forth above justify the inference, I believe, that none but the topographic designation of the precise situation of the rectal lesion is of reliable surgical significance.

Dissection of many rectums of rabbits, cats, dogs and monkeys proved that these animals are not provided with rectal valves.

DEFECATION.

“Defecation is partly a voluntary and partly a reflex act. But in the infant the voluntary control has not yet been developed; in the adult it may be lost by disease; in an animal it may be abolished by operation; in each case the action becomes wholly reflex. In the normal course of events, the rectum which is empty and quiescent in the intervals of defecation, is excited to contraction as soon as feces begin to enter it through the sigmoid flexure, and the sensations caused by their presence give rise to the desire to empty the bowels. This desire may for a time be resisted by the will, or it may be yielded to. In the latter case the abdominal muscles are forcibly contracted, and the glottis being closed, the whole effect of their contraction is expended in raising the pressure within the abdomen and pelvis.... The sphincter ani is now relaxed by the inhibition of a center in the lumbar portion of the spinal cord, through the activity of which the tonic contraction of the sphincter is normally maintained. This relaxation is partially voluntary, the impulses that come from the brain acting probably through the medium of the lumbar center; but in the dog, after section of the cord in the dorsal region, the whole act of defecation, including contraction of the abdominal muscles and relaxation of the sphincter, still takes place, and here the process must be purely reflex. The contraction of the levatores ani helps to resist overdistention of the pelvic floor and to pull the anus up over the feces as they escape.”[16]

The above paragraph concisely represents the accepted interpretation of the act of defecation. The rectal valve, an individual anatomic organ in itself, must, however, be reckoned with in studying the operations of the integral mechanism of defecation.

DIGITAL OBSERVATION OF THE NONANESTHETIZED SUBJECT.

In the normal rectum, when the first rectal valve can be reached by the finger, provided it be immediately discovered on the introduction of the finger, a definite but not rigid band of tissue may be felt buried behind the masses of lax mucosa. This band presents at one side that which seems to be a circular aperture of variable diameter; a few seconds’ application of the passive finger detects a gradual relaxation of what first had seemed a ring-like constriction till the finger can make out but an indefinite thickening on a side of the gut-wall. If the finger be held passive, this constriction may again surround the finger; but if so, it does so with a somewhat weaker grasp. Often the presence of the finger within the rectum excites a peristalsis-like contraction, during which the valve usually cannot be detected. When the rectum is filled with water, the valve is sometimes more readily discoverable by the finger, and when discovered, the diameter of the valve-strait is greater than that before noticed, and the grasping tendency of the valve is not so noticeable.

OCULAR OBSERVATION OF THE ANESTHETIZED SUBJECT.

If a somewhat emaciated male be selected, one whose rectum is susceptible to atmospheric inflation while in the lithotomy posture, and if the large intestine be freed of its contents, if such a subject be anesthetized and his colon or sigmoid filled with water, and the anus divulsed and held open with the speculum, the water confined to the rectum may be bailed out, and the rectum will then be seen to present the multichambered condition already described. If the inquirer will now place a hand on the abdomen over the sigmoid flexure, and give the part a quick, firm pressure, his watchful eye may observe a downward rush of waters into the rectum, first striking the concave wall formed by the juncture of the upper surface of the uppermost visible valve and the adjoining rectal wall, bounding from this surface to the opposite next lower valve, from which the stream is deflected to a lower point on the opposite wall, by which time all may be obscured by a wave of contracting peristalsis, rhythmically repeated, which may project small quantities of water through the anus. In the intervals of the contractions, the rectal chambers are observed to be either submerged or else atmospherically inflated.

OCULAR OBSERVATION OF THE NONANESTHETIZED SUBJECT.

If a subject under proctoscopy be directed to bear down, it is observable that the empty and atmospherically inflated rectum closes under the compression of the voluntary forces by the concave anterior wall becoming convex, and being carried backward toward the fixed posterior wall, the transverse diameters remaining apparently but little shortened. The compression may be noticed as being applied from before and in a backward direction, and simultaneously from above downwardly. In case firm fecal masses, or lubricated balls of cotton experimentally placed, are dejected by these efforts, there will be noticeable depression of the valve-floor under the pressure of the descending mass. Presently the mass will appear at the valve-edge, where it may seem suspended for a few seconds before it is plunged on into the next lower chamber. Occasional rhythmic contractions of the rectal muscular coats occur, which fill and transitorily obscure the field under observation with masses of the reduplicated mucosa, and it is always possible to note that such contractions have changed the positions of the gut’s contents.

These anatomic findings and physiologic observations warrant the conclusion that the rectal valve has a function. Its histologic elements endow it with essentially passive and active properties. When the muscular elements are relaxed and the gut is either greatly dilated or else in a lesser measure distended, the valve is passively projected across the channel to resist the hurried or uncontrolled descent of the feces. The presence of the bands of fibrous tissue under the free margin of the valve provides a guard or _control_ to receive and retain the bolus, or, I may say, the valves receive a series of boluses, till a sufficient pressure is made to stimulate the complex involuntary mechanism of defecation to an expulsion of the feces or to a reversed peristalsis. The presence of the feces or the involuntary movements incident to their presence, signals the consciousness to cooperative voluntary expulsory effort, or gives warning of the necessity of voluntary resistance. In the event of the exercise of these forces in the direction of resistance there seems to be some reason to believe that an antiperistalsis returns the feces to the sigmoid flexure. The same arrangement which sets in operation the involuntary factors of defecation also provides for the minimum expenditure of energy on the part of the voluntary forces for the reason that the gut’s contents are collected on the surface of the unyielding sacrum and steadied there to receive the pressure of the really expulsory voluntary effort. Such an arrangement of the feces as is mentioned above further facilitates defecation for the reason that the entire contents of the rectum are not rushed upon the anus at once. The surgeon remembers that it is usually impossible to reduce a hernia _en masse_.

The bundles of circular muscular fibers which constitute the muscular element of the valve evidently belong to the same mechanism and have the same function as those which form the ental sphincter. Their usual state may be that of tonic contraction; they are relaxed by inhibition; when the muscle is in a state of inaction the fibrous bands are projected and support the valves across the channel of the rectum. In health the valve is susceptible, under pressure, of a temporary effacement.

If it be the function of the normal rectal valve to beneficently retard the descent of the feces it is obviously true that it may be the especial property of the valve, in certain other than normal conditions, to maliciously obstruct the descent of the feces.

My experience convinces me that a perfect knowledge of the rectal valve constitutes the key to an understanding of obstipation, rectal stricture, and their sequels.

OBSTIPATION IN INFANTS.

The infant strains at stool because of the imperfect development of the anatomic features concerned in the mechanism of defecation. These are as follows:

1. The infant’s lower gut is muscularly deficient.

2. Its great length and its mobility within the abdomen are obstructive to defecation.

3. The rectal valves are obstructive.

4. The infant’s anus not being sufficiently expansible is also obstructive to the descent of feces.

The specimens of infant rectums and sigmoids here pictured are all fairly illustrative of the facts upon which the foregoing declarations are based.

The dried specimens shown in the illustrations were prepared by flushing the intestine and then fixing the subject in the genuacromial posture; the anus was then fixed open and melted paraffin was injected under about twelve ounces’ pressure. When the cast had hardened, that portion of the gut which it occupied, was removed. Specimens shown in Figs. 43 and 44 were prepared by placing the subject upon its back and by opening the descending colon; the intestine below was then washed out and the colon perforation fixed at the abdominal wound, which, save for this point, was sewed up, the anus was tied up and as much melted paraffin as would enter under two-pounds’ pressure was forced into the gut; subsequently the sigmoid and rectum were removed as in the other instances. After immersion in alcohol the specimens were varnished.

Following are the memoranda of a few of the autopsies made in this study:

CASE 1.--Female, stillborn, height 16 inches (40.64 cm.);
circumference at anterior superior spinous process 7½ inches
(19.05 cm.); anterior superior spinous process diameter 3
inches (7.62 cm.); ensiform to pubes 4 inches (10.16 cm.);
transverse diameter pelvic outlet ¾ inch (1.90 cm.);
peritoneum at last vertebra of coccyx. (Fig. 35).

CASE 2.--Female, aged 1 hour, height 17 inches (43.18 cm.);
circumference at anterior superior spinous process 7½ inches
(19.05 cm.); anterior superior spinous process diameter 2½
inches (6.35 cm.); ensiform to pubes 4 inches (10.16 cm.);
transverse diameter pelvic outlet ½ inch (1.27 cm.); peritoneum
at last vertebra of coccyx. (Fig. 37).

CASE 3.--Male, aged 1 month, height 23 inches (58.42 cm.);
circumference at anterior superior spinous process 9 inches
(22.86 cm.); anterior superior spinous process diameter 3½
inches (8.89 cm.); ensiform to pubes 4 inches (10.16 cm.);
transverse diameter pelvic outlet ⅝ inch (1.59 cm.); peritoneum
at last vertebra of coccyx.

CASE 4.--Female, aged 6 weeks, height 24 inches (60.96 cm.);
circumference at anterior superior spinous process 10½ inches
(26.67 cm.); anterior superior spinous process diameter 3
inches (7.62 cm.); ensiform to pubes 5½ inches (13.97 cm.);
transverse diameter pelvic outlet ⅝ inch (1.59 cm.); peritoneum
at last vertebra of coccyx. (Fig. 41).

CASE 5.--Female, aged 2 months, height 20 inches (50.80 cm.);
circumference at anterior superior spinous process 8 inches
(20.32 cm.); anterior superior spinous process diameter 3
inches (7.62 cm.); ensiform to pubes 3½ inches (8.89 cm.);
transverse diameter pelvic outlet ¾ inch (1.90 cm.); peritoneum
at last vertebra of coccyx. (Fig. 49).

CASE 6.--Male, aged 6 months, height 24 inches (60.96 cm.);
circumference at anterior superior spinous process 10 inches
(25.40 cm.); anterior superior spinous process diameter 4
inches (10.16 cm.); ensiform to pubes 5 inches (12.70 cm.);
transverse diameter pelvic outlet ¾ inch (1.90 cm.); peritoneum
at last sacral vertebra. (Fig. 43).

CASE 7.--Male, aged 6 months, height 24 inches (60.96 cm.);
circumference at anterior superior spinous process 12 inches
(30.48 cm.); anterior superior spinous process diameter 4
inches (10.16 cm.); ensiform to pubes 5 inches (12.70 cm.);
transverse diameter pelvic outlet ¾ inch (1.90 cm); peritoneum
at first bone of coccyx. (Fig. 44).

CASE 8.--Male, aged 17 months, height 25 inches (63.50 cm.);
circumference at anterior superior spinous process 12 inches
(30.48 cm.); anterior superior spinous process diameter 4
inches (10.16 cm.); ensiform to pubes 6 inches (15.24 cm.);
transverse diameter pelvic outlet 1 inch (2.54 cm.); peritoneum
at last sacral vertebra.

Examination of the pictures of _the dried specimens reveals that the wall of the infant rectum and sigmoid flexure is thin_ compared to that of the adult.

It is impossible to distinguish the longitudinal muscular bands which are so apparent in the gut of the adult. The infant gut being very deficient in muscular elements, therefore the intrinsic power of peristalsis cannot be present in that degree necessary to it as a component factor of defecation.

_The relations of the peritoneum to the rectum_ of the infant also contribute to the difficulties of defecation, as also does the relatively _great length of the descending colon and sigmoid flexure_. In young children the length of sigmoidal mesentery from its attachment to the parietes to its invagination of the lower loop of the sigmoid is often greater than the distance from the promontory of the sacrum to the distal bone of the coccyx. (See Figs. 44 and 45.) From the sigmoidorectal juncture to the beginning of the middle third of the rectum the mesentery rapidly shortens but apparently completely invests the upper third of the rectum. The middle and lower thirds are not so completely invested, and present upon their posterior parts a vertical lane bare of peritoneum, from the borders of which the peritoneum is reflected in lateral directions. This uncovered part of the gut is not applied directly to the sacrum and coccyx. There is a space between which is occupied by loose connective tissue. The distance from the dorsal parietes to the gut is variable here, being from one-half to one-fourth of an inch (1.27 to .63 cm.). At the beginning of the middle third there is usually a gradual decrease in the length of the peritoneal band as it descends, till it is one-eighth or possibly but one-sixteenth of an inch (.32 or .16 cm.) in length at the last bone of the coccyx; it rapidly shortens from this point to its termination. The parietal peritoneum descends over the ischial tuberosities and approaches nearly to the ental sphincter muscle. In the newly-born the peritoneum is situated within one-fourth inch (.63 cm.) of the anal skin.

The disproportionately great length of the descending colon and mesentery of the infant obviously contributes to the possibility of angulation of the gut.

We may see in the presence in the child of lax and long, or relatively long, peritoneal ligaments, and in the great length of the descending colon and the consequent probability of numerous acute angulations in the infant sigmoid and rectum, and in the mobility of these parts within the abdomen, the possibility of development of a perfect adult mechanism for defecation. The essential features of this development are two: (1) the growth of prostate or uterus and their supports which relatively fix the lower rectum; and (2) the downgrowth and outgrowth of the pelvic bones and the consequent conversion of mesenteric peritoneum to parietal peritoneum, which shortens the adult mesentery and in some measure fixes the upper rectum; thus the entire rectum is steadied to facilitate discharge when the mechanism of defecation is set in operation.

The diagrammatic figures do not exaggerate these obstructive elements. The collateral muscles which assist in the performance of the act of defecation force the feces in the direction of the lower angle in each flexion, and in that flexion whose onward, or, to be paradoxic, whose downward direction for the time points upward (Fig. 46), the auxiliary pressure is in the direction opposite to that of peristalsis.

Inspection of the pictures of the dried specimens reveals the angulations referred to, which may be expected to be more numerous the more segmentary the gut’s contents.

_The third feature obstructive to defecation in infants is the rectal valve._ It is a feature and factor which not only is not recognized, but is one whose very anatomic existence has been persistently disputed by Matthews, Kelsey, and others. It was imperfectly described as an anatomic feature of the rectum by Mr. Houston in the Dublin Hospital Reports in 1830, and in 1887 Dr. Walter A. Otis more practically demonstrated its presence; neither of these gentlemen, however, attributed to it the characteristic element of an anatomic valve, although happily and by chance bestowing upon it its proper name. A number of investigators have discovered this organ and have miscalled it by various names and given it widely varying descriptions; but a greater number still deny its existence and critically strive to dissolve away the imperfect evidence recorded in medical literature.[17]

The pictures here shown of the dried specimens prove that in the infant the valve is such a matter of fact that its existence is no longer a question for debate.

The fetal specimens pictured indicate that the valves are particularly well developed early in embryonic life. The infant specimen shown in Fig. 49 is marked by two valves, situated so close together that the middle portion of the rectum presents its longest diameter at right angles to the main direction of the gut. Another valve may be seen at the juncture of the upper portion and the sigmoid flexure.

It must be readily seen that the presence in the rectum of such a structure as an anatomic valve would be essentially obstructive to the passage of feces.

In studying the physics of the rectum it is important that we recognize that the posterior wall from which the mesentery is reflected is less movable than other parts in the circumference, hence distention of the rectum not only tends to carry a given point of its wall away from the point opposite to it, but also carries it away from a given point cephalad or caudad. So it may be assumed that if the two valves situated at the middle of the cast-distended dried specimen (Fig. 49) are three-eighths of an inch (.95 cm.) separated, and that the two opposite walls of the rectum in the portion bounded by these valves are one inch (2.54 cm.) apart, that in a state of the gut’s collapse or systole the valves would be in contact, and thus afford a very definite obstruction to the descent of semisolid feces.

The _bony pelvic outlet_ in the infant is so contracted that the limits of anal expansion are such as to almost defeat the passage through it of other than fluid feces. It should be remembered that the normal average measurement from ischial tuberosity to ischial tuberosity in the adult is about four inches (10.16 cm.), and it is a fact proven by our observation that the average transverse diameter of the newly-born infant’s pelvic outlet is but a little more than one-half inch (1.27 cm.), the pubococcygeal measurement is even less. Those who are familiar with instrumental divulsion of the adult anus may have observed that two and a quarter inches (5.71 cm.) is the average limit of lateral separation of the anus, the remaining portion of the pelvic outlet being filled with the compressed soft tissues of the ischiorectal space. Therefore it may be estimated that nine-sixteenths at most, of the diameter of the pelvic outlet is the reasonable limit of expansibility of the anus for the passage of feces. Applying this calculation to the infant we find that if the ischial tuberosities are one-half inch (1.27 cm.) separated, that the anal expansibility is but five-sixteenth of an inch (.79 cm.), which is, as we know, the diameter of a No. 22 sound (French scale). Reference to the paraffin cast of the infant gut (Fig. 51) indicates that the average distensibility of the sigmoid flexure and rectal chambers, in which the feces when firm are formed, is four or five times that of the anal expansibility; thus it is readily perceived that compared to the adult the juxtaposition of the ischial tuberosities in the infant supplies a most obstinate obstructive factor in defecation.

To collate in brief:

1. The muscular development of the adult rectum and lower sigmoid is plainly apparent in the plates here exhibited of the fresh specimens. A deficient muscularity is observed in the infant specimens.

2. The peritoneal band of these parts in the adult is observed to be, relatively, very considerably shorter than that in the infant, and the sigmoid flexure is relatively shorter.

3. The rectal valves appear to bear the same proportion to the gut in both adult and infant, but when we remember the difference in muscular development in the two the disproportionately greater resistance of the valve in the infant rectum is obvious.

4. The anal expansibility is remembered as adequate in the adult, and is seen to be deficient in the infant.

Correlative to the facts just stated we must recognize that the adult rectum has resident within its own wall a powerful expulsive muscular mechanism; that the shortening of the mesentery holds the upper rectum steady under the applied auxiliary forces; that the angulations of the normal sigmoid are not necessarily obstructive, though in a desirable measure retardative; that the forward incline of the lower sacrum and coccyx behind, and the development of the uterus and prostate and their inherent supports in front, provide the lower adult rectum with a firm funnel-like arrangement which guides the feces directly upon the os internum of the anus; that the valves divide the feces into portions to facilitate their separate successive discharge, and finally in sequence, that the physiologic descent of the structures of the ischiorectal space reduces this last resistance to the minimum in adult defecation.

Straining, the ruptures and prolapses, obstipation, retention of feces, and the multitudinous consequent ills demand our consideration, though this study forces the conclusion, I believe, that the individual’s escape is ultimately assured by process of development, and that for the normally formed infant, the physician will find the solution of the problem of difficult defecation in the solution of the stool.

TREATMENT.

Diet, hygroscopic suppositories, and fluid injections which may render more fluid the intestinal contents will favor their descent through the convoluted gut, the valvulated rectum, and the contracted anus.

Massage of the abdomen over the region of the colon aids in (1) the development of the auxiliary abdominal muscles of defecation and of the intrinsic expulsory muscles in the intestinal wall; and further, such manipulations (2) directly propel the gut’s contents along the tortuous course of the bowel and hence (3) reduce, inasmuch as they may overcome the obstructive features of the valve.