The region, in the axis of the anal canal, until it reaches the cavity of the rectum, the inferior part of which is dilated to form the ampulla. The transverse folds of the rectum or valves of Houston, three in number, project into the cavity of the bowel in the form of prominent crescentic shelves, which are produced by the three permanent or true flexures into which the rectum is thrown (Birmingham); the inferior valve, which may be sufficiently prominent to impede the passage of the finger, must not be mistaken for a pathological condition. Through the anterior wall the finger can palpate from below up-ben wards the bulb of the urethra, the membranous part of the urethra, the bulbo-urethral glands (when inflamed and enlarged), the apex and lateral lobes of the prostate, the Ex vesiculæ seminales, and the external trigone of the bladder. With the left forefinger in the rectum, an instrument passed into the bladder can be distinctly felt as it traverses the mem The sacrum has been sawn across through the 4th sacral vertebra, and its inferior part removed with the coccyx. The posterior portions of the coccygei, levatores ani, and of the external sphincter have been cut away. The "pinching in" of the inferior end of the rectum by the medial edges of the levatores ani, resulting in the formation of the flattened anal canal, is suggested in the illustration, which has been made from a formalin-hardened male body, aged thirty. The lateral inflections of the rectum, corresponding to Houston's rectal valves, are also shown. (From Birmingham.) branous urethra ; as it lies in the prostatic urethra it is separated from the finger by the prostate. Hence, when a false passage is made through the bulbous or membranous portion of the urethra, the instrument, if pushed onwards towards the bladder, will be felt immediately outside the rectum between it and the prostate. In the child, owing to the rudimentary condition of the prostate, the instrument is distinctly felt close to the rectum, as it lies in the prostatic as well as in the membranous portion of the urethra. When the prostate is not enlarged the tip of the finger can just reach the external trigone, which is most distinctly felt when the bladder is full. The vesiculæ seminales, indistinctly felt when healthy, may be readily palpated when enlarged and indurated from disease. Through the side wall of the rectum may be palpated the ischio-rectal fossa, the bony wall of the pelvis minor, and, when enlarged, the hypogastric lymph glands; through the posterior wall the hollow of the sacrum and coccyx, and the lymph glands lying in the retrorectal cellular tissue. In the child rectal examination enables one to palpate, in addition to the structures in the cavity of the pelvis minor, those which occupy the lower segment of the abdomen. When the bladder is empty even a small calculus can be readily felt by recto-abdominal palpation. The distance of the apex of the recto-vesical pouch of peritoneum from the anus varies considerably, according to the degree of distension of the bladder and rectum; when both are empty it reaches to about 2 in. from the anus; when both are distended it is at least one inch higher (Fig. 1108). Examination by Sigmoidoscope. In introducing the sigmoidoscope into the pelvic colon the direction of the anal canal and the curve of the rectum must be borne in mind; as the instrument traverses the anal canal it must be directed forwards as well as upwards, after which it is pushed onwards, in a backward and upward direction, towards the hollow of the sacrum; while, finally, in order to reach the pelvic colon, it is again directed forwards and a little to the left so as to clear the promontory of the sacrum. The instrument is more difficult to pass in women, on account of the greater abruptness of the curvature of the sacrum in the female as compared with the male. When examined with the sigmoidoscope the mucous membrane of the rectum is seen to possess a deep red colour, and an excellent view is obtained of the rectal valves of Houston. The most conspicuous fold, known as the plica transversalis, projects from the right wall about the level of the recto-vesical peritoneal reflection, i.e. about three inches from the anus. The highest valve, situated at the colo-rectal junction, gives rise to a distinct narrowing which must not be mistaken for a stricture. The pulsations of the left common iliac artery can generally be seen to be communicated to the postero-lateral wall of the pelvic colon about four inches from the anus. Removal of the Rectum.-In removing the rectum and anal canal for malignant disease, an incision is carried round the anus and then upwards and backwards over the coccyx and inferior half of the sacrum. The ano-coccygeal raphe is divided longitudinally and the coccyx (either alone or along with more or less of the lower part of the sacrum) is excised by dividing the structures attached to its margins, viz., the inferior fibres of the gluteus maximus, the coccygeus, and the sacro-tuberous and sacro-spinous ligaments (O.T. greater and lesser sacro-sciatic). The parietal pelvic fascia, here very thin and adherent, is removed along with the bone. The middle sacral artery is ligatured. This is now seen, stretching across the floor of the wound, a well-defined sheet of fascia, viz., the rectal layer of the visceral pelvic fascia, which is divided longitudinally and stripped to either side off the posterior surface of the rectum; in doing this the branches of the middle hæmorrhoidal arteries, and, higher up, the two divisions of the superior hæmorrhoidal are encountered and ligatured. Anteriorly, the anal canal is detached from the central point of the perineum, after which the anterior surface of the rectum is freed from below upwards from the urogenital diaphragm containing the membranous urethra, the posterior surface of the prostate, the trigone of the bladder and the vesiculæ seminales and the ductus deferentes. This procedure is facilitated by the existence of a cellular interval between the anterior wall of the rectum and the strong recto-vesical layer of visceral pelvic fascia, which forms the posterior part of the sheath of the prostate, and, higher up, encloses the vesiculæ seminales and ductus deferentes. In order to strike this cellular interspace, the surgeon, after dividing the central point of the perineum transversely, deepens the incision down to the apex of the prostate. In doing this he divides a band of muscular fibres (recto-urethral muscle) which passes from the anterior wall of the lowest part of the rectal ampulla to blend with the sphincter urethræ muscle surrounding the urethra at the apex of the prostate. It is these recto-urethral fibres, which, by pulling forwards the ampulla, bring it into close relation with the urethra; hence it is especially at this stage of the operation that great care must be taken not to open into the rectum or to wound the urethra. After exposing the apex of the prostate the next step is to retract the anal canal well backwards and to define the anterior or pubo-prostatic borders of the levator ani muscle. These muscles are then divided, on each side, a little above their insertion into the rectum. The posterior surface of the prostate, covered with recto-vesical fascia, is now exposed. By continuing the separation of the rectum upwards in the cellular plane above mentioned, the bottom of the recto-vesical pouch of peritoneum is reached; it can usually be stripped for some distance off the rectum, without opening into the peritoneal cavity. In freeing the rectum laterally, bands of connective tissue containing branches of the middle and superior hæmorrhoidal vessels are divided. If the tumour is situated at the superior part of the rectum, the recto-vesical pouch of peritoneum is freely opened in a transverse direction. The colo-rectal junction is then mobilised by dividing the sacral attachment of the pelvic mesocolon and securing the superior hæmorrhoidal artery. After dividing the rectum well above the tumour, the opening into the peritoneal cavity is closed by suturing together the anterior and posterior walls of the recto-vesical pouch. If a permanent colostomy has been established, the divided bowel is closed; if not, a sacral anus is made. FEMALE PELVIS. On opening the abdomen by a median incision extending from the umbilicus to the pubes, and looking into the pelvis minor from above, after displacing some coils of the small intestine upwards, the fundus of the uterus, directed forwards and a little upwards, is seen resting upon the superior surface of the bladder. Behind the uterus is the rectum, and between the two the recto-uterine pouch of Douglas, containing the pelvic colon and the inferior part of the ileum. The ovary lies a little below the level of the superior aperture of the pelvis minor upon a triangular shelf, bounded in front by the broad ligament, behind and medially by the uterosacral ligament, and behind and laterally by the pelvic wall. When the vermiform process overhangs the superior aperture of the pelvis minor its tip may come into close relation with the right ovary, a condition which often leads to a difficulty in distinguishing an inflammation of that ovary from appendicitis. The round ligaments are seen passing forwards and laterally from the upper parts of the right and left borders of the uterus to the abdominal inguinal rings, which lie immediately in front and to the medial side of the terminations of the external iliac arteries. Inferiorly and at the medial side of the round ligament, as it leaves the pelvis, is the inferior epigastric artery. By pulling the uterus upwards the attachments of the broad ligament to the floor and side walls of the pelvis are brought into evidence, as also are the utero-vesical and recto-vaginal peritoneal pouches; the former is shallow, while the deepest part of the latter covers the upper fourth of the posterior wall of the vagina, and comes into relation, therefore, with the posterior fornix. The utero-vesical peritoneal reflection takes place at the level of the junction of the body of the uterus with the cervix. The anterior wall of the cervix comes into relation, therefore, with the superior part of the base of the bladder, from which. however, it is separated by a layer of loose connective tissue. It is the existence of this cellular plane which enables the surgeon to separate the bladder readily from the uterus in the operation of hysterectomy. While the anterior wall of the vagina is firmly united to the urethra, its posterior wall, on the other hand, can be readily separated from the rectum, in consequence of the interposition between the two organs of the recto-vaginal fascia The ureter crosses the brim of the pelvis in front of the bifurcation of the common iliac artery 1 in. lateral to and a little below the centre of the sacral promontory. The corresponding point on the anterior abdominal wall is at the junction of the lateral and middle thirds of a line joining the anterior superior spines of the ilium. After crossing the termination of the common iliac artery from lateral to medial side, the ureter dips vertically into the pelvis minor behind the peritoneum covering the hypogastric artery. It then courses medially in the parametric cellular tissue below the base of the broad ligamenta. In this position it lies a little above the lateral fornix of the vagina, about three-quarters of an inch lateral to the superior part of the cervix uteri; finally, just before it pierces ate The Enders perforu The Th the lateral angle of the bladder, it lies in front of the antero-lateral aspect of the upper part of the vaginal wall. The relation of the pelvic portions of the ureters are of special importance in the female as their close relation to the cervix uteri and upper part of the vagina renders them liable to injury, more especially in the operation of hysterectomy performed for malignant disease of the uterus. The uterine artery, in the first part of its course, passes downwards and forwards a little anterior and lateral to the ureter. At the level of the orificium internum uteri it takes a medial direction and passes along the inferior border of the broad ligament, and crosses, above and in front of the inferior part of the ureter, from lateral to medial side; it then passes above the lateral fornix of the vagina and finally ascends close to the side of the body of the uterus, and ends by anastomosing with the ovarian artery below the isthmus of the uterine tube. The ovarian artery enters the pelvis minor between the layers of that portion of the broad ligament known as the ligamentum suspensorium ovarii; it is here that the vessel may be most readily ligatured in abdominal hysterectomy, and in ovariotomy. The lymph vessels from the inferior part of the vagina pass to the superficial vaginal and sacral glands, while those from the rest of the vagina, from the cervix uteri and from the body of the uterus, pass to the hypogastric, the external iliac, and the sacral glands. The hypogastric glands are situated on the side wall of the pelvis in close relation to the origins of the branches of the hypogastric artery. The sacral glands form a chain along the medial side of the anterior sacral foramina. The lymph vessels from the fundus of the uterus, and from the ovary, terminate in the glands around the aorta. The external genitals are fully described elsewhere (p. 1324). The external orifice of the urethra, surrounded by a slight annular prominence of the mucous membrane, is situated about 1 in. behind the clitoris, immediately above the centre of the base of the vestibule-a smooth triangular area at the anterior part of the vulva, with its sides formed by the labia minora and its base by the anterior margin of the ostium vaginæ. In passing a catheter the instrument is directed along the forefinger (introduced just within the ostium vagina with the palmar surface towards the symphysis pubis) to the base of the smooth vestibule, where it is tilted slightly upwards so as to bring its point opposite the urethral orifice. The larger vestibular glands, about the size of a bean, are placed on each side of the posterior third of the orifice of the vagina, below the urogenital diaphragm. Their ducts, nearly one inch in length, open posteriorly between the hymen and the posterior commissure (fossa navicularis). Abscesses and cysts not infrequently develop in connexion with these glands. The bulbs of the vestibule are two piriform collections of erectile tissue situated on each side of the vestibule, between the bulbo-cavernosus muscle and the inferior fascia of the urogenital diaphragm. Rupture of these bodies gives rise to the condition known as pudendal hæmatocele. The cervix uteri projects downwards and backwards into the roof of the vagina so as to leave a distinct fornix between the two. The relations of the fornix are of so much practical importance that for descriptive purposes it is customary to subdivide it into an anterior, a posterior, and two lateral portions. The anterior fornix, which is shallow, is related to the base of the bladder and to the utero-vesical pouch of peritoneum. The posterior fornix, which is deeper, extends upwards for some little distance in front of the anterior wall of the lowest part of the pouch of Douglas. The septum between the two is formed merely by the wall of the vagina; hence the readiness with which the pelvis may be drained by puncturing it and pulling a tube through the opening from the pelvis into the vagina. The lateral fornix lies below the medial part of the base of the broad ligament. An incision carried through it would therefore open into the parametric cellular tissue and would expose the uterine artery as it passes transversely to the uterus, after crossing above and in front of the lower part of the ureters. Vaginal Examination. In making a vaginal examination the patient should be placed in the dorsal position, with the thighs well flexed; the index-finger of the right hand is now carried along the fold of the buttock towards the median plane, where it will impinge against the posterior aspect of the introitus vagina, whence it is inserted Exposure of Kidney from behind.-In exposing the kidney from the loin, by a vertical incision between the lateral border of the sacrospinalis and the free posterior border of the external oblique muscle, the following structures are divided from without inwards: (1) the integuments; (2) the lower fibres of the latissimus dorsi and serratus posterior inferior muscles; (3) the middle layer of the lumbar aponeurosis, just lateral to the sacrospinalis compartment, and parallel to the lateral fibres of the quadratus lumborum muscles; (4) the anterior layer of the lumbar aponeurosis (which forms the aponeurotic origin of the transversus muscles), and the transversalis fascia; (5) the paranephric fat; (6) the perinephric fascia; (7) the perinephric fat surrounding the true capsule of the kidney. The kidney may be readily mobilised and brought to the surface by shelling it out of its fatty capsule FIG. 1109.-DISSECTION OF THE SPLEEN, LIVER, AND KIDNEYS FROM BEHIND, IN A SUBJECT HARDENED BY FORMALIN INJECTION. (From Cunningham.) with the finger. Better access to the renal vessels can be obtained if the incision is made a little nearer the median plane, so as to open into the sacrospinalis compart ment. This allows of the muscle itself being retracted medially more efficiently. In exposing the kidney by an oblique incision in the loin, the latissimus dors and serratus posterior inferior muscles are divided at the medial part of the wound, while at its lateral part the posterior fibres of the external and internal oblique muscles are divided; next, the aponeurotic origin of the transversus muscle and the transversalis fascia are split so as to expose the extra-peritoneal fat and the peritoneum, as it is reflected from the ascending colon on to the lateral aspect of the abdominal wall. The latter structures are then strippe forwards and medially off the anterior surface of the kidney, until the hilum and renal vessels are reached. The sacrospinalis and quadratus lumborum muscles are retracted well medially, and it is often necessary to divide the lateral fibres of the quadratus muscle. |