LYMPHATIC VESSELS AND NODES OF ABDOMEN AND PELVIS

1. Lymphatic vessels and nodes of abdomen and pelvis

2.     Lumbar part of sympathetic trunk and abdominal division of vagus. Autonomic plexus of abdomen

3.     Pelvic part of sympathetic trunk. Pelvic division of the parasympathetic nervous system. Autonomic plexus of pelvis

 

Lesson # 31

 

Theme 1. Lymphatic vessels and nodes of abdomen and pelvis

The Lymphatics of the Abdomen

In abdominal cavity, as and in pelvis, lymphatic nodes may be divided into two sets, parietal and visceral.

The Visceral lymphatic nodes dispose along the course of big vessels come away from abdominal aorta, they receive lymph from all internal abdominal organs: coeliac nodes, right/left gastric nodes, lymphatic unnulus of cardia, right/left gastroepiploic nodes, pyloric nodes, pancreatic nodes, splenic nodes, pancreatoduodenal nodes, hepatic nodes, superior mesenteric nodes and inferior mesenteric nodes. The lymphatic vessels of the small intestine receive the special designation of lacteals or chyliferous vessels; they differ in no respect from the lymphatic vessels generally excepting that during the process of digestion they contain a milk-white fluid, the chyle. The lymphatic vessels and nodes of the small intestine positioned in mesentery and empty into intestinal trunk. The vessels take away lymph from these nodes, pass to lumbar nodes. Efferent vessels of last form the lumbar trunks, which flowing together form a thoracic duct.

The parietal Lymph nodes of the pelvis.

 

The parietal lymphatic nodes disposed around aortae and inferior vene cava  - right/left and intermidiate lumbar nodes, lateral aortic nodes, preaortic nodes, retroaortic nodes, lateral caval nodes, precaval nodes, retrocaval nodes, inferior phrenic nodes and inferior epigastric nodes.

    Lymphatic vessels of superior half of abdominal wall pass upward to the axillar lymphatic nodes. The vessels of inferior half of abdominal wall pass downward to inguinal lymphatic nodes.

The Lymph nodes of the Abdomen and Pelvis—The Lymph nodes of the abdomen and pelvis may be divided, from their situations, into (a) parietal, lying behind the peritoneum and in close association with the larger bloodvessels; and (b) visceral, which are found in relation to the visceral arteries.

 

 

The parietal nodes include the following groups:

 

  The External Iliac Nodes, from eight to ten in number, lie along the external iliac vessels. They are arranged in three groups, one on the lateral, another on the medial, and a third on the anterior aspect of the vessels; the third group is, however, sometimes absent. Their principal afferents are derived from the inguinal and subinguinal glands, the deep lymphatics of the abdominal wall below the umbilicus and of the adductor region of the thigh, and the lymphatics from the glans penis vel clitoridis, the membranous urethra, the prostate, the fundus of the bladder, the cervix uteri, and upper part of the vagina.

  The Common Iliac Glands, four to six in number, are grouped behind and on the sides of the common iliac artery, one or two being placed below the bifurcation of the aorta, in front of the fifth lumbar vertebra. They drain chiefly the hypogastric and external iliac glands, and their efferents pass to the lateral aortic glands.

  The Epigastric nodes (lymphoglandulæ epigastricæ), three or four in number, are placed alongside the lower portion of the inferior epigastric vessels.

  The Iliac Circumflex nodes, two to four in number, are situated along the course of the deep iliac circumflex vessels; they are sometimes absent.

  The Hypogastric nodes (lymphoglandulæ hypogastricæ; internal iliac gland)  surround the hypogastric vessels, and receive the lymphatics corresponding to the distribution of the branches of the hypogastric artery, i. e., they receive lymphatics from all the pelvic viscera, from the deeper parts of the perineum, including the membranous and cavernous portions of the urethra, and from the buttock and back of the thigh. An obturator gland is sometimes seen in the upper part of the obturator foramen.

  The Sacral nodes are placed in the concavity of the sacrum, in relation to the middle and lateral sacral arteries; they receive lymphatics from the rectum and posterior wall of the pelvis.

  The efferents of the hypogastric group end in the common iliac glands.

  The Lumbar nodes (lymphoglandulæ lumbales) are very numerous, and consist of right and left lateral aortic, preaortic, and retroaortic groups.

Iliopelvic glands (lateral view).

 

  The right lateral aortic nodes are situated partly in front of the inferior vena cava, near the termination of the renal vein, and partly behind it on the origin of the Psoas major, and on the right crus of the diaphragm. The left lateral aortic glands form a chain on the left side of the abdominal aorta in front of the origin of the Psoas major and left crus of the diaphragm. The glands on either side receive (a) the efferents of the common iliac glands, (b) the lymphatics from the testis in the male and from the ovary, uterine tube, and body of the uterus in the female; (c) the lymphatics from the kidney and suprarenal gland; and (d) the lymphatics draining the lateral abdominal muscles and accompanying the lumbar veins. Most of the efferent vessels of the lateral aortic glands converge to form the right and left lumbar trunks which join the cisterna chyli, but some enter the pre- and retroaortic glands, and others pierce the crura of the diaphragm to join the lower end of the thoracic duct. The preaortic glands lie in front of the aorta, and may be divided into celiac, superior mesenteric, and inferior mesenteric groups, arranged around the origins of the corresponding arteries. They receive a few vessels from the lateral aortic glands, but their principal afferents are derived from the viscera supplied by the three arteries with which they are associated. Some of their efferents pass to the retroaortic glands, but the majority unite to form the intestinal trunk, which enters the cisterna chyli. The retroaortic glands are placed below the cisterna chyli, on the bodies of the third and fourth lumbar vertebræ. They receive lymphatic trunks from the lateral and preaortic glands, while their efferents end in the cisterna chyli.

 

 

 

the Lymphatic Vessels of the Abdomen and Pelvis

  The lymphatic vessels of the walls of the abdomen and pelvis may be divided into two sets, superficial and deep.

  The superficial vessels follow the course of the superficial bloodvessels and converge to the superficial inguinal glands; those derived from the integument of the front of the abdomen below the umbilicus follow the course of the superficial epigastric vessels, and those from the sides of the lumbar part of the abdominal wall pass along the crest of the ilium, with the superficial iliac circumflex vessels. The superficial lymphatic vessels of the gluteal region turn horizontally around the buttock, and join the superficial inguinal and subinguinal glands.

  The deep vessels run alongside the principal bloodvessels. Those of the parietes of the pelvis, which accompany the superior and inferior gluteal, and obturator vessels, follow the course of the hypogastric artery, and ultimately join the lateral aortic glands.

 Lymphatic Vessels of the Perineum and External Genitals.—The lymphatic vessels of the perineum, of the integument of the penis, and of the scrotum (or vulva), follow the course of the external pudendal vessels, and end in the superficial inguinal and subinguinal glands. Those of the glans penis vel clitoridis terminate partly in the deep subinguinal glands and partly in the external iliac glands.

 

 The visceral nodes are associated with the branches of the celiac, superior and inferior mesenteric arteries. Those related to the branches of the celiac artery form three sets, gastric, hepatic, and pancreaticolienal.

  The Gastric nodes consist of two sets, superior and inferior.

  The Superior Gastric nodes (lymphoglandulæ gastricæ superiores) accompany the left gastric artery and are divisible into three groups, viz.: (a) upper, on the stem of the artery; (b) lower, accompanying the descending branches of the artery along the cardiac half of the lesser curvature of the stomach, between the two layers of the lesser omentum; and (c) paracardial outlying members of the gastric glands, disposed in a manner comparable to a chain of beads around the neck of the stomach (Jamieson and Dobson ). They receive their afferents from the stomach; their efferents pass to the celiac group of preaortic glands.

  The Inferior Gastric nodes (lymphoglandulæ gastricæ inferiores; right gastroepiploic gland), four to seven in number, lie between the two layers of the greater omentum along the pyloric half of the greater curvature of the stomach.

  The Hepatic nodes (lymphoglandulæ hepaticæ) consist of the following groups: (a) hepatic, on the stem of the hepatic artery, and extending upward along the common bile duct, between the two layers of the lesser omentum, as far as the porta hepatis; the cystic nodes, a member of this group, is placed near the neck of the gall-bladder; (b) subpyloric, four or five in number, in close relation to the bifurcation of the gastroduodenal artery, in the angle between the superior and descending parts of the duodenum; an outlying member of this group is sometimes found above the duodenum on the right gastric (pyloric) artery. The glands of the hepatic chain receive afferents from the stomach, duodenum, liver, gall-bladder, and pancreas; their efferents join the celiac group of preaortic glands.

  The Pancreaticolienal nodes (lymphoglandulæ pancreaticolienales; splenic glands)  accompany the lienal (splenic) artery, and are situated in relation to the posterior surface and upper border of the pancreas; one or two members of this group are found in the gastrolienal ligament (Jamieson and Dobson, op. cit.). Their afferents are derived from the stomach, spleen, and pancreas, their efferents join the celiac group of preaortic glands.

Lymphatics of stomach

 

Lymphatics of stomach, etc. The stomach has been turned upward.

 

The lymphatics of cecum and vermiform process from the front.

 

The lymphatics of cecum and vermiform process from behind.

 

  The superior mesenteric nodes may be divided into three principal groups: mesenteric, ileocolic, and mesocolic.

  The Mesenteric nodes (lymphoglandulæ mesentericæ) lie between the layers of the mesentery. They vary from one hundred to one hundred and fifty in number, and may be grouped into three sets, viz.: one lying close to the wall of the small intestine, among the terminal twigs of the superior mesenteric artery; a second, in relation to the loops and primary branches of the vessels; and a third along the trunk of the artery.

  The Ileocolic nodes, from ten to twenty in number, form a chain around the ileocolic artery, but show a tendency to subdivision into two groups, one near the duodenum and another on the lower part of the trunk of the artery. Where the vessel divides into its terminal branches the chain is broken up into several groups, viz.: (a) ileal, in relation to the ileal branch of the artery; (b) anterior ileocolic, usually of three glands, in the ileocolic fold, near the wall of the cecum; (c) posterior ileocolic, mostly placed in the angle between the ileum and the colon, but partly lying behind the cecum at its junction with the ascending colon; (d) a single gland, between the layers of the mesenteriole of the vermiform process; (e) right colic, along the medial side of the ascending colon.

Lymphatics of colon.

 

  The Mesocolic nodes (lymphoglandulæ mesocolicæ) are numerous, and lie between the layers of the transverse mesocolon, in close relation to the transverse colon; they are best developed in the neighborhood of the right and left colic flexures. One or two small glands are occasionally seen along the trunk of the right colic artery and others are found in relation to the trunk and branches of the middle colic artery.

  The superior mesenteric glands receive afferents from the jejunum, ileum, cecum, vermiform process, and the ascending and transverse parts of the colon; their efferents pass to the preaortic glands.

  The inferior mesenteric nodes consist of: (a) small glands on the branches of the left colic and sigmoid arteries; (b) a group in the sigmoid mesocolon, around the superior hemorrhoidal artery; and (c) a pararectal group in contact with the muscular coat of the rectum. They drain the descending iliac and sigmoid parts of the colon and the upper part of the rectum; their efferents pass to the preaortic glands.

 

The Lymphatic Vessels of the Abdominal and Pelvic Viscera  The lymphatic vessels of the abdominal and pelvic viscera consist of (1) those of the subdiaphragmatic portion of the digestive tube and its associated glands, the liver and pancreas; (2) those of the spleen and suprarenal glands; (3) those of the urinary organs; (4) those of the reproductive organs.

  1. The lymphatic vessels of the subdiaphragmatic portion of the digestive tube are situated partly in the mucous membrane and partly in the seromuscular coats, but as the former system drains into the latter, the two may be considered as one.

  The Lymphatic Vessels of the Stomach are continuous at the cardiac orifice with those of the esophagus, and at the pylorus with those of the duodenum. They mainly follow the bloodvessels, and may be arranged in four sets. Those of the first set accompany the branches of the left gastric artery, receiving tributaries from a large area on either surface of the stomach, and terminate in the superior gastric glands. Those of the second set drain the fundus and body of the stomach on the left of a line drawn vertically from the esophagus; they accompany, more or less closely, the short gastric and left gastroepiploic arteries, and end in the pancreaticolienal glands. The vessels of the third set drain the right portion of the greater curvature as far as the pyloric portion, and end in the inferior gastric glands, the efferents of which pass to the subpyloric group. Those of the fourth set drain the pyloric portion and pass to the hepatic and subpyloric glands, and to the superior gastric glands.

  The Lymphatic Vessels of the Duodenum consist of an anterior and a posterior set, which open into a series of small pancreaticoduodenal glands on the anterior and posterior aspects of the groove between the head of the pancreas and the duodenum. The efferents of these glands run in two directions, upward to the hepatic glands and downward to the preaortic glands around the origin of the superior mesenteric artery.

  The Lymphatic Vessels of the Jejunum and Ileum are termed lacteals, from the milk-white fluid they contain during intestinal digestion. They run between the layers of the mesentery and enter the mesenteric glands, the efferents of which end in the preaortic glands.

  The Lymphatic Vessels of the Vermiform Process and Cecum are numerous, since in the wall of this process there is a large amount of adenoid tissue. From the body and tail of the vermiform process eight to fifteen vessels ascend between the layers of the mesenteriole, one or two being interrupted in the gland which lies between the layers of this peritoneal fold. They unite to form three or four vessels, which end partly in the lower and partly in the upper glands of the ileocolic chain. The vessels from the root of the vermiform process and from the cecum consist of an anterior and a posterior group. The anterior vessels pass in front of the cecum, and end in the anterior ileocolic glands and in the upper and lower glands of the ileocolic chain; the posterior vessels ascend over the back of the cecum and terminate in the posterior ileocolic glands and in the lower glands of the ileocolic chain.

 

Lymphatic Vessels of the Colon

—The lymphatic vessels of the ascending and transverse parts of the colon finally end in the mesenteric glands, after traversing the right colic and mesocolic glands. Those of the descending and iliac sigmoid parts of the colon are interrupted by the small glands on the branches of the left colic and sigmoid arteries, and ultimately end in the preaortic glands around the origin of the inferior mesenteric artery.

 

 

 

 

Lymphatic Vessels of the Anus, Anal Canal, and Rectum.—The lymphatics from the anus pass forward and end with those of the integument of the perineum and scrotum in the superficial inguinal glands; those from the anal canal accompany the middle and inferior hemorrhoidal arteries, and end in the hypogastric glands; while the vessels from the rectum traverse the pararectal glands and pass to those in the sigmoid mesocolon; the efferents of the latter terminate in the preaortic glands around the origin of the inferior mesenteric artery.

  The Lymphatic Vessels of the Liver are divisible into two sets, superficial and deep. The former arise in the subperitoneal areolar tissue over the entire surface of the organ, and may be grouped into (a) those on the convex surface, (b) those on the inferior surface.

  (a) On the convex surface: The vessels from the back part of this surface reach their terminal glands by three different routes; the vessels of the middle set, five or six in number, pass through the vena-caval foramen in the diaphragm and end in one or two glands which are situated around the terminal part of the inferior vena cava; a few vessels from the left side pass backward toward the esophageal hiatus, and terminate in the paracardial group of superior gastric glands; the vessels from the right side, one or two in number, run on the abdominal surface of the diaphragm, and, after crossing its right crus, end in the preaortic glands which surround the origin of the celiac artery. From the portions of the right and left lobes adjacent to the falciform ligament, the lymphatic vessels converge to form two trunks, one of which accompanies the inferior vena cava through the diaphragm, and ends in the glands around the terminal part of this vessel; the other runs downward and forward, and, turning around the anterior sharp margin of the liver, accompanies the upper part of the ligamentum teres, and ends in the upper hepatic glands. From the anterior surface a few additional vessels turn around the anterior sharp margin to reach the upper hepatic glands.

  (b) On the inferior surface: The vessels from this surface mostly converge to the porta hepatis, and accompany the deep lymphatics, emerging from the porta to the hepatic glands; one or two from the posterior parts of the right and caudate lobes accompany the inferior vena cava through the diaphragm, and end in the glands around the terminal part of this vein.

  The deep lymphatics converge to ascending and descending trunks. The ascending trunks accompany the hepatic veins and pass through the diaphragm to end in the glands around the terminal part of the inferior vena cava. The descending trunks emerge from the porta hepatis, and end in the hepatic glands.

  The Lymphatic Vessels of the Gall-bladder pass to the hepatic glands in the porta hepatis; those of the common bile duct to the hepatic glands alongside the duct and to the upper pancreaticoduodenal glands.

  The Lymphatic Vessels of the Pancreas follow the course of its bloodvessels. Most of them enter the pancreaticolienal glands, but some end in the pancreaticoduodenal glands, and others in the preaortic glands near the origin of the superior mesenteric artery.

  2. The lymphatic vessels of the spleen and suprarenal glands.

  The Lymphatic Vessels of the Spleen, both superficial and deep, pass to the pancreaticolienal glands.

  The Lymphatic Vessels of the Suprarenal Glands usually accompany the suprarenal veins, and end in the lateral aortic glands; occasionally some of them pierce the crura of the diaphragm and end in the glands of the posterior mediastinum.

  3. The lymphatic vessels of the urinary organs.

  The Lymphatic Vessels of the Kidney form three plexuses: one in the substance of the kidney, a second beneath its fibrous capsule, and a third in the perinephric fat; the second and third communicate freely with each other. The vessels from the plexus in the kidney substance converge to form four or five trunks which issue at the hilum. Here they are joined by vessels from the plexus under the capsule, and, following the course of the renal vein, end in the lateral aortic glands. The perinephric plexus is drained directly into the upper lateral aortic glands.

  The Lymphatic Vessels of the Ureter run in different directions. Those from its upper portion end partly in the efferent vessels of the kidney and partly in the lateral aortic glands; those from the portion immediately above the brim of the lesser pelvis are drained into the common iliac glands; while the vessels from the intrapelvic portion of the tube either join the efferents from the bladder, or end in the hypogastric glands.

Lymphatics of the bladder.

 

  The Lymphatic Vessels of the Bladder originate in two plexuses, an intra- and an extramuscular, it being generally admitted that the mucous membrane is devoid of lymphatics. The efferent vessels are arranged in two groups, one from the anterior and another from the posterior surface of the bladder. The vessels from the anterior surface pass to the external iliac glands, but in their course minute glands are situated. These minute glands are arranged in two groups, an anterior vesical, in front of the bladder, and a lateral vesical, in relation to the lateral umbilical ligament. The vessels from the posterior surface pass to the hypogastric, external, and common iliac glands; those draining the upper part of this surface traverse the lateral vesical glands.

  The Lymphatic Vessels of the Prostate terminate chiefly in the hypogastric and sacral glands, but one trunk from the posterior surface ends in the external iliac glands, and another from the anterior surface joins the vessels which drain the membranous part of the urethra.

 

Lymphatic Vessels of the Urethra.—The lymphatics of the cavernous portion of the urethra accompany those of the glans penis, and terminate with them in the deep subinguinal and external iliac glands. Those of the membranous and prostatic portions, and those of the whole urethra in the female, pass to the hypogastric glands.

Lymphatics of the prostate.

 

  (4) The lymphatic vessels of the reproductive organs.

  The Lymphatic Vessels of the Testes consist of two sets, superficial and deep, the former commencing on the surface of the tunica vaginalis, the latter in the epididymis and body of the testis. They form from four to eight collecting trunks which ascend with the spermatic veins in the spermatic cord and along the front of the Psoas major to the level where the spermatic vessels cross the ureter and end in the lateral and preaortic groups of lumbar glands. 

  The Lymphatic Vessels of the Ductus Deferens pass to the external iliac glands; those of the vesiculæ seminales partly to the hypogastric and partly to the external glands.

  The Lymphatic Vessels of the Ovary are similar to those of the testis, and ascend with the ovarian artery to the lateral and preaortic glands.

  The Lymphatic Vessels of the Uterine Tube pass partly with those of the ovary and partly with those of the uterus.

  The Lymphatic Vessels of the Uterus consist of two sets, superficial and deep, the former being placed beneath the peritoneum, the latter in the substance of the organ. The lymphatics of the cervix uteri run in three directions: transversely to the external iliac glands, postero-laterally to the hypogastric glands, and posteriorly to the common iliac glands. The majority of the vessels of the body and fundus of the uterus pass lateralward in the broad ligaments, and are continued up with the ovarian vessels to the lateral and preaortic glands; a few, however, run to the external iliac glands, and one or two to the superficial inguinal glands. In the unimpregnated uterus the lymphatic vessels are very small, but during gestation they are greatly enlarged.

Lymphatics of the uterus.

 

  The Lymphatic Vessels of the Vagina are carried in three directions: those of the upper part of the vagina to the external iliac glands, those of the middle part to the hypogastric glands, and those of the lower part to the common iliac glands. On the course of the vessels from the middle and lower parts small glands are situated. Some lymphatic vessels from the lower part of the vagina join those of the vulva and pass to the superficial inguinal glands. The lymphatics of the vagina anastomose with those of the cervix uteri, vulva, and rectum, but not with those of the bladder.

 

In pelvic area differ the visceral and parietal lymphatic nodes.

The visceral lymphatic nodes dispose near pelvic organs and they are: paravesical, prevesical and retrovesical nodes, lateral vesical nodes, parauterine nodes, paravaginal nodes and pararectal or anоrectal nodes. The efferent vessels from these nodes paso ls into iliac nodes, mainly to common iliac nodes and to retroaortic nodes. Lymph flows from ovaries intumbar nodes.

The parietal lymphatic nodes disposed along the course of big vessels common iliac nodes; internal iliac nodes, which unite gluteal and sacral nodes. External iliac nodes join obturator nodes. The efferent vessels from these nodes pass first into common iliac nodes, then into retroaortic nodes, and from them - into lumbar lymphatic nodes.

 

 

 

Theme 2. Lumbar part of sympathetic trunk and abdominal division of vagus. Autonomic plexus of abdomen

 

The lumbar ganglia of lumbar department of sympathetic trunk are represented by 4-5 ganglia and interganglionic branches. These ganglia are found on anterior-lateral surface of lumbar vertebrae bodies. The lumbar ganglia of right and left sympathetic trunk unite between oneself by communicating branches. The first and second lumbar ganglia approach the communicating white branches. Each ganglion gives off the gray communicating branches to lumbar spinal nerves and lumbar splanchnic nerves, which pass to abdominal plexus and have both preganglionic and postganglionic nervous fibers.

Preganglionic fibers in composition of major and minor splanchnic nerves, and also lumbar splanchnic nerves approach to the prevertebral sympathetic ganglia, which lie at the anterior surface of backbone closely to celiac trunk and superior mesenteric artery. This semilunar-shaped celiac ganglia, superior mesenteric ganglion, aortorenal ganglia, phrenic ganglia, renal ganglia and some other.  Postganglionic fibres from them pass to organs together with blood vessels and form same name plexus. Celiac plexus (the biggest) supplies a liver, spleen, stomach, pancreas, small intestine and large intestine (to descending colon).

The abdominal portion of the sympathetic trunk.

 is situated in front of the vertebral column, along the medial margin of the Psoas major. It consists usually of four lumbar ganglia, connected together by interganglionic cords. It is continuous above with the thoracic portion beneath the medial lumbocostal arch, and below with the pelvic portion behind the common iliac artery. The ganglia are of small size, and placed much nearer the median line than are the thoracic ganglia.

  Gray rami communicantes pass from all the ganglia to the lumbar spinal nerves. The first and second, and sometimes the third, lumbar nerves send white rami communicantes to the corresponding ganglia. The rami communicantes are of considerable length, and accompany the lumbar arteries around the sides of the bodies of the vertebræ, passing beneath the fibrous arches from which some of the fibers of the Psoas major arise.

Abdominal portion of the sympathetic trunk, with the celiac and hypogastric plexuses.

 

  Of the branches of distribution, some pass in front of the aorta, and join the aortic plexus; others descend in front of the common iliac arteries, and assist in forming the hypogastric plexus.

 

 

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Celiac plexus continues around abdominal aorta, forming abdominal aortic plexus. It innervates kidney, suprarenal glands, ureters and testicles (ovaries).

Inferior mesenteric plexus starts closely to inferior mesenteric artery. It innervates descending and sigmoid colon, superior part of the rectum. Superior hypogastric plexus located in point of aortic bifurcation. It receives splanchnic nerves from lower lumbar and upper sacral sympathetic ganglia. Superior hypogastric plexus divides into right and left inferior hypogastric plexuses lower then promontorium. Inferior hypogastric plexus reaches the organs and tissues of lesser pelvis with arterial branches from internal iliac artery. It innervates seminal vesicles, prostate (male) uterus, Fallopian tubes, vagina (female), also rectum, urinary bladder.

Abdominal part of vagus nerve is represented by anterior and posterior vagal trunks, which originate from esophageal plexus. Anterior vagal trunk located on front surface of the stomach and gives branches gives off the anterior gastric and hepatic branches. Posterior vagal trunk supplies back gastric wall, and gives off coeliac branches to reach coeliac plexus. Then fibers of vagus nerve with sympathetic fibers supply the liver, spleen, pancreas, kidneys, small and large intestine (including a upper department of descending colon).

 The Gastric Branches (rami gastrici) are distributed to the stomach. The right vagus forms the posterior gastric plexus on the postero-inferior surface of the stomach and the left the anterior gastric plexus on the antero-superior surface.

  The Celiac Branches (rami cæliaci) are mainly derived from the right vagus: they join the celiac plexus and through it supply branches to the pancreas, spleen, kidneys, suprarenal bodies, and intestine.

  The Hepatic Branches (rami hepatici) arise from the left vagus: they join the hepatic plexus and through it are conveyed to the liver.C:\Documents and Settings\xata\Application Data\gray\henry gray anatomy\www.bartleby.com\107\218.html - i847

The great plexuses of the sympathetic are aggregations of nerves and ganglia, situated in the thoracic, abdominal, and pelvic cavities, and named the cardiac, celiac, and hypogastric plexuses. They consist not only of sympathetic fibers derived from the ganglia, but of fibers from the medulla spinalis, which are conveyed through the white rami communicantes. From the plexuses branches are given to the thoracic, abdominal, and pelvic viscera.

The Celiac Plexus (Plexus Cœliacus; Solar Plexus) —The celiac plexus, the largest of the three sympathetic plexuses, is situated at the level of the upper part of the first lumbar vertebra and is composed of two large ganglia, the celiac ganglia, and a dense net-work of nerve fibers uniting them together. It surrounds the celiac artery and the root of the superior mesenteric artery. It lies behind the stomach and the omental bursa, in front of the crura of the diaphragm and the commencement of the abdominal aorta, and between the suprarenal glands. The plexus and the ganglia receive the greater and lesser splanchnic nerves of both sides and some filaments from the right vagus, and give off numerous secondary plexuses along the neighboring arteries.

  The Celiac Ganglia (ganglia cæliaca; semilunar ganglia) are two large irregularlyshaped masses having the appearance of Lymphatic Nodes and placed one on either side of the middle line in front of the crura of the diaphragm close to the suprarenal glands, that on the right side being placed behind the inferior vena cava. The upper part of each ganglion is joined by the greater splanchnic nerve, while the lower part, which is segmented off and named the aorticorenal ganglion, receives the lesser splanchnic nerve and gives off the greater part of the renal plexus.

  The secondary plexuses springing from or connected with the celiac plexus are the

Phrenic.

Renal.

Hepatic.

Spermatic.

Lienal.

Superior mesenteric.

Superior gastric.

Abdominal aortic.

Suprarenal.

Inferior mesenteric.

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  The phrenic plexus (plexus phrenicus) accompanies the inferior phrenic artery to the diaphragm, some filaments passing to the suprarenal gland. It arises from the upper part of the celiac ganglion, and is larger on the right than on the left side. It receives one or two branches from the phrenic nerve. At the point of junction of the right phrenic plexus with the phrenic nerve is a small ganglion (ganglion phrenicum). This plexus distributes branches to the inferior vena cava, and to the suprarenal and hepatic plexuses.

  The hepatic plexus (plexus hepaticus), the largest offset from the celiac plexus, receives filaments from the left vagus and right phrenic nerves. It accompanies the hepatic artery, ramifying upon its branches, and upon those of the portal vein in the substance of the liver. Branches from this plexus accompany all the divisions of the hepatic artery. A considerable plexus accompanies the gastroduodenal artery and is continued as the inferior gastric plexus on the right gastroepiploic artery along the greater curvature of the stomach, where it unites with offshoots from the lienal plexus.

The celiac ganglia with the sympathetic plexuses of the abdominal viscera radiating from the ganglia.

 

  The lienal plexus (plexus lienalis; splenic plexus) is formed by branches from the celiac plexus, the left celiac ganglion, and from the right vagus nerve. It accompanies the lienal artery to the spleen, giving off, in its course, subsidiary plexuses along the various branches of the artery.

  The superior gastric plexus (plexus gastricus superior; gastric or coronary plexus) accompanies the left gastric artery along the lesser curvature of the stomach, and joins with branches from the left vagus.

  The suprarenal plexus (plexus suprarenalis) is formed by branches from the celiac plexus, from the celiac ganglion, and from the phrenic and greater splanchnic nerves, a ganglion being formed at the point of junction with the latter nerve. The plexus supplies the suprarenal gland, being distributed chiefly to its medullary portion; its branches are remarkable for their large size in comparison with that of the organ they supply.

 

 

  The renal plexus (plexus renalis) is formed by filaments from the celiac plexus, the aorticorenal ganglion, and the aortic plexus. It is joined also by the smallest splanchnic nerve. The nerves from these sources, fifteen or twenty in number, have a few ganglia developed upon them. They accompany the branches of the renal artery into the kidney; some filaments are distributed to the spermatic plexus and, on the right side, to the inferior vena cava.

  The spermatic plexus (plexus spermaticus) is derived from the renal plexus, receiving branches from the aortic plexus. It accompanies the internal spermatic artery to the testis. In the female, the ovarian plexus (plexus arteriæ ovaricæ) arises from the renal plexus, and is distributed to the ovary, and fundus of the uterus.

  The superior mesenteric plexus (plexus mesentericus superior) is a continuation of the lower part of the celiac plexus, receiving a branch from the junction of the right vagus nerve with the plexus. It surrounds the superior mesenteric artery, accompanies it into the mesentery, and divides into a number of secondary plexuses, which are distributed to all the parts supplied by the artery, viz., pancreatic branches to the pancreas; intestinal branches to the small intestine; and ileocolic, right colic, and middle colic branches, which supply the corresponding parts of the great intestine. The nerves composing this plexus are white in color and firm in texture; in the upper part of the plexus close to the origin of the superior mesenteric artery is a ganglion (ganglion mesentericum superius).

  The abdominal aortic plexus (plexus aorticus abdominalis; aortic plexus) is formed by branches derived, on either side, from the celiac plexus and ganglia, and receives filaments from some of the lumbar ganglia. It is situated upon the sides and front of the aorta, between the origins of the superior and inferior mesenteric arteries. From this plexus arise part of the spermatic, the inferior mesenteric, and the hypogastric plexuses; it also distributes filaments to the inferior vena cava.

  The inferior mesenteric plexus (plexus mesentericus inferior) is derived chiefly from the aortic plexus. It surrounds the inferior mesenteric artery, and divides into a number of secondary plexuses, which are distributed to all the parts supplied by the artery, viz., the left colic and sigmoid plexuses, which supply the descending and sigmoid parts of the colon; and the superior hemorrhoidal plexus, which supplies the rectum and joins in the pelvis with branches from the pelvic plexuses.

 

The Hypogastric Plexus (Plexus Hypogastricus)—The hypogastric plexus is situated in front of the last lumbar vertebra and the promontory of the sacrum, between the two common iliac arteries, and is formed by the union of numerous filaments, which descend on either side from the aortic plexus, and from the lumbar ganglia; it divides, below, into two lateral portions which are named the pelvic plexuses.

        The ganglia lie on the anterolateral surface of the lumbar vertebrae on the medial border of the psoas major muscle. White communicating branches are sent only to the superior two or three lumbar nerves.

Along its entire distance the abdominal part of the sympathetic trunk sends off a great number of branches which, together with the greater and lesser splanchnic nerves and the abdominal segments of the vagus nerves, form the largest unpaired coeliac plexus (plexus celiacus). Numerous spinal ganglia (C₅-L₃) also take part in its formation. The coeliac plexus lies on the anterior semicircumference of the abdominal aorta behind the pancreas and surrounds the initial parts of the coeliac trunk (truncus celiacus) and the superior mesenteric artery. It occupies an area between the renal arteries, the suprarenal glands, and the aortic opening of the diaphragm and includes the paired ganglion of the coeliac artery—coeliac ganglion (gang­lion celiacum), and sometimes the unpaired ganglion of the superior mesen­teric artery—superior mesenteric ganglion (ganglion mesentericum superius) lying under the root of this artery.

The coeliac plexus also gives off some smaller paired plexuses to the diaphragm_T. suprarenals, and kidneys as well as the testicular (ovarian) plexus (plexus testicularis [ovaricus]) extending along the course of the arteries of the same name. There are also a series of unpaired plexuses which pass to some organs along the walls of arteries whose names they are given. Among these is the superior mesenteric plexus (plexus mesentericus superior) which supplies the pancreas, the small intestine and the large intestine to half the length of the transverse colon, and the ovary.

The second main source of innervation of the abdominal organs is the plexus on the aorta—aortic plexus {plexus aorticus abdominalis), formed by two trunks arising from the coeliac plexus and branches running from the lumbar ganglia of the sympathetic trunk. The aortic plexus gives rise to the inferior mesenteric plexus (plexus mesentericus inferior) for the transverse, descending, and sigmoid colon, and the upper part of the rectum (the superior rectal plexus, plexus rect.alis superior). At the origin of the inferior mesenteric plexus lies the inferior mesenteric ganglion (ganglion mesentericum inferius) whose postganglionic fibres pass to the pelvis as com­ponents of the hypogastric nerves.

The aortic plexus is continuous with the unpaired hypogastric plexus (plexus hypogastricus superior) which bifurcates at the promontory of the sacrum and is in turn continuous with the pelvic plexus (plexus hypogastricus inferior s. plexus pelvinus). Fibres derived from the superior lumbar segments are functionally vasomotor (vasoconstrictor) in relation to the penis and motor in relation to the uterus and the sphinter urethrae muscle.

The sacral, or pelvic, part usually has four ganglia. Lying on the ante­rior surface of the sacrum along the medial margin of the anterior sacral fora­men, both trunks gradually converge to terminate as one common unpaired ganglion impar on the anterior surface of the coccyx. The ganglia of the pelvic part, like those of the lumbar part, are connected both by small longitudinal and transverse trunks.

From the ganglia of the sacral part of the sympathetic trunk arise some in the pelvic plexus: (1) anteroinferior part in which are distinguished a supe­rior portion innervating the urinary bladder, the vesical plexus (plexus vesi- calis) and an inferior portion supplying the prostatic gland, the prostatic plexus (plexus prostaticus), the seminal vesicles and ductus deferens, the plexus of the vas deferens (plexus deferentialis), and the cavernous bodies, cavernous nerves of the penis (nervi cavernosi penis), (2) posterior part of the plexus supplies the rectum, the middle and inferior rectal plexuses (plexus rectales medii and infe- riores). A third, middle part, is distinguished, in addition, in females; its inferior portion sends branches to the uterus and vagina, the uterovaginal plex­us (plexus uterovaginalis) and the cavernous bodies of the clitoris, the cavern­ous nerves of the clitoris (nervi cavernosi clitoridis), while the superior portion gives off branches to the uterus and ovaries.

 

 

 INNERVATION OF THE GASTRO INTESTINAL TRACT (TO THE LEVEL OF THE SIGMOID COLON), PANCREAS, AND LIVER

The afferent outflow from these organs occurs along fibres which are constituents of the vagus and the lesser and greater splanchnic nerves, the hepatic and coeliac plexuses, and the thoracic and lumbar spinal nerves, and, according to some authors, also of the phrenic nerve.

The sympathetic nerves conduct the sense of pain from these organs; the vagus nerve conducts the other afferent impulses as well as the sense of nausea and hunger from the stomach.

Efferent parasympathetic innervation. Preganglionic fibres from the dorsal vegeta­tive nucleus of the vagus nerve pass as components of the last named to. the terminal gang­lia in the tissues of the organs discussed. In the intestine these are the cells of the intestinal plexuses (the myenteric and submucous plexuses). From the ganglia the postganglionic fibres run to the smooth muscles and glands. Function: stimulation of peristalsis of the stomach, relaxation of the pyloric sphincter, stimulation of peristalsis of the intestine and gall bladder. The vagus nerve contains fibres which stimulate and inhibit secretion. ESerent parasympathetic innervation is also concerned with dilation of vessels.

Efferent sympathetic innervation. The preganglionic fibres emerge from the lateral horns of the fifth to twelfth spinal segments and then pass in the corresponding white com­municating branches into the sympathetic trunk and then without interruption, as com­ponents of the greater splanchnic nerves (between the sixth and ninth ganglia), reach the intermediate ganglia contributing to the formation of the coeliac and mesenteric plexuses. Here arise the postganglionic fibres which as components of the coeliac and superior mes­enteric plexuses extend to the liver, pancreas, the small and large intestine and to the level of the middle of the transverse colon; the left half of the transverse colon and the descending colon are innervated by the inferior mesenteric plexus.

  The plexuses mentioned supply the muscles and glands of the organs discussed. Function: inhibition of gastric, intestinal and gall bladder peristalsis, constriction of the blood vessels, and inhibition pf glandular secretion.

It should be added that the movement of the gastric and intestinal contents can also be delayed because the sympathetic nerves cause active contraction of the pyloric, intes­tinal, and other sphincters.

INNERVATION OF THE SIGMOID COLON, RECTUM, AND URINARY BLADDER

 

The afferent pathways run as components in the inferior mesenteric, superior and in­ferior hypogastric plexuses, and in the pelvic splanchnic nerves.

Efferent parasympathetic innervation. The preganglionic fibres arise in the lateral horns of the second to fourth sacral spinal segments and emerge as components of the cor­responding anterior roots of the spinal nerves. They then pass as the pelvic splanchnic nerves to the intraorganic ganglia of the parts of the large intestine discussed and to the ganglia located around the urinary bladder. All these ganglia give rise to the postgang­lionic fibres which reach the smooth muscles of the organs. Function: stimulation of peri­stalsis of the sigmoid colon and rectum, relaxation of the sphincter and internus muscle, contraction of the detrusor urinae, and relaxation of the sphincter vesical muscle.

Efferent sympathetic innervation. The preganglionic fibres pass from the lateral horns of the lumbar spinal cord through the corresponding anterior roots into the white communicating branches, run without interruption through the sympathetic trunk, and Beach the inferior mesenteric ganglion. In this ganglion arise the postganglionic fibres which then extend as components of the hypogastric nerves to the smooth muscles of the organs discussed. Function: inhibition of peristalsis of the sigmoid colon and rectum and contrac­tion of the sphincter and internus muscle. The sympathetic nerves in the urinary bladder cause relaxation of the detrusor urinae and contraction of the sphincter urethrae muscle.

Innervation of the reproductive organs is discussed on (sympathetic) and (parasympathetic). The innervation of the other internal organs is discussed in the sections dealing with their description.

INNERVATION OF THE BLOOD VESSELS

The extent of innervation of the arteries, capillaries, and veins differs. Arteries with well developed muscular elements in the tunica media are supplied with nerves most richly, the veins are supplied less richly; the inferior vena cava and the portal vein occupy an intermediate position.

The larger vessels situated in the body cavities receive innervation from branches of the sympathetic trunk, the nearest plexuses of the vegetative system, and the adjoining spinal nerves; the peripheral vessels of the cavitary walls and the vessels of the limbs are supplied by nerves passing close to them. Nerves approaching the vessels run segmentally and form perivascular plexuses which give off branches; after penetrating the wall these branches are distributed in the adventitia.(tunica externa) and between it and tunica me­dia. The fibres supply the muscular structures of the wall for which purpose their termi­nations are shaped differently. It has been proved to date that receptors are present in all arteries, veins, and lymphatic vessels.

The first neuron of the afferent outflow from the vascular system is in the intervertebral ganglia or in the ganglia of the vegetative nerves (the splanchnic and the vagus nerves); it then passes as a component of the conductor of the interoceptive analyser . The vasomotor centre is in the medulla oblongata. The globus pallidus, thalamus, and tuber cinereum are concerned with the regulation of circulation. The higher centres of circulation, like the centres of all vegetative functions, are located in the cortex of the cerebral motor zone (the frontal lobe) and in front and to the back of it. According to the certain data, the cortical centre of the vascular function analyser is evidently found in all parts of the cortex. The efferent connections of the brain with the stem and spinal centres are evidently effected by the pyramidal and extrapyramidal tracts.

Closure of the reflex arc may occur at all levels of the central nervous system. Some authors believe that it may also be accomplished in the peripheral part of the nervous system through Dogiel’s cells of the second type located in the ganglia of the vegetative plexuses (the vegetative refiex arc proper).

The efferent path causes a vasomotor effect, i.e. dilation or constriction of the ves­sels. The vasoconstricting fibres pass in the sympathetic nerves, the vasodilating fibres run. in all parasympathetic nerves of the cranial part of the vegetative system (third, seventh ninth, and tenth pairs), in the posterior roots of the spinal nerves (not all authors share this viewpoint), and in the parasympathetic nerves of the sacral part (the splanchnic pel­vic nerves).

There is disagreement concerning efferent innervation of the capillaries. Some authors claim that capillaries, being devoid of muscular elements, are also devoid of the cor­responding efferent innervation; others have described nerve endings on capillaries lo­cated in the brain parenchyma (axovasal connections).

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Theme 3. Pelvic part of sympathetic trunk. Pelvic division of the parasympathetic nervous system. Autonomic plexus of pelvis

The parasympathetic centres lie in the spinal cord, in the intermediolaterai nucleus (nucleus intermediolateralis) of the lateral horn at the level of the second to fourth sacral segments.

 

 

THE PERIPHERAL PART OF THE PARASYMPATHETIC SYSTEM

The peripheral part of the cranial parasympathetic system consists of the following structures: (1) preganglionic fibres passing in the third, seventh, ninth, and tenth pairs of cranial nerves (according to Mitchell, also in the first and eleventh pairs); (2) terminal ganglia lying close to the organs, namely, the ciliary, sphenopalatine, submandibular, and optic ganglia, and (3) postganglionic fibres which either stretch independently, e.g. the short ciliary nerves arising from the ciliary ganglion, or pass in some other nerves, e.g. postganglionic fibres originating from the otic ganglion and running in the auriculotemporal nerve. Certain authors claim that the parasympathetic fibres also emerge from different segments of the spinal cord through the dorsal roots and pass to the walls of the trunk and the limbs

The peripheral part of the sacral parasympathetic system consists of fibres which run in the anterior roots of the second, third, and fourth sacral nerves, then in their anterior branches forming the sacral plexus (somatic plexus) and finally enter the true pelvis. In the pelvis they leave the plexus and as the pelvic splanchnic nerves (nn. splanchnici pelvini) pass to the pelvic plexus (plexus hypogastricus inferior) together with which they innervate the pelvic organs (the rectum with the sigmoid colon, the urinary bladder, and the external and internal genitalia). Stimulation of the pelvic splanchnic nerves causes contraction of the rectum and bladder (m. detrusor urinae) with relaxation of their sphincter muscles. The fibres of the sympathetic hypogastric plexus, in contrast, delay the evacuation of these organs; they stimulate uterine contractions, while the pelvic splanchnic nerves inhibit it. The pelvic splanchnic nerves also contain vasodilator fibres (nn. erigentes) for the cavernous bodies of the penis and clitoris which are responsible for erection. The parasympathetic fibres arising from the sacral segment of the spinal cord extend to the pelvic plexuses not only in the erigentes and pelvic splanchnic nerves but also in the pudendal nerve (the preganglionic fibres). According to certain data, the pudendal nerve is a complex nerve containing, in addition to somatic fibres, vegetative (sympathetic and parasympathetic) fibres that form part of the inferior hypogastric plexus. The sympathetic fibres arising from the ganglia of the sacral segment of the sympathetic trunk as postganglionic fibres join the pudendal nerve in the true pelvis and pass through the inferior hypogastric plexus to the pelvic organs.

The intramural nervous system also belongs to the parasympathetic nervous system.

The walls of some hollow organs contain nerve plexuses of small gang­lia (terminal) with ganglionic cells and non-medulated fibres; this is the gang- liono-reticular, or intramural system.

This system has been studied most completely by Soviet scientists (Dogel, Lavrentyev, Vorobyev, and Kolosov). Leontovich discovered a diff­use nervous network in some tissues (“Leontovich’s network”). The intra­mural system is particularly developed in the digestive tract where it is re­presented by several plexuses.

1.     The myenteric (Auerbach’s) plexus {plexus myentericus Auerbachii) lies between the longitudinal and circular muscles of the digestive tube.

2.     The submucous (Meissner’s) plexus (plexus submucosus Meissneri) is located in the submucous tissue. It is continuous with the plexus of the glands and villi. The “Leontovich’s network” is to the periphery of the above-named plexuses.

The plexuses receive nerve fibres from the sympathetic and parasym­pathetic systems. In the intramural plexuses the preganglionic fibres of the parasympathetic systems are switched over to the postganglionic fibres.

Sacral ganglia of sympathetic trunk formed by 4 ganglia, which lie on pelvic surface of sacrum, medially from pelvic sacral foramen. The right and left sympathetic trunks terminate in unpaired (coccigeal) ganglion. The sacral ganglia of right and left side unite each other by transversal branches. They give off communicating gray branches for sacral spinal nerves and sacral splanchnic nerves, which pass to superior and inferior hypogastric autonomic (vegetative) plexus.

Superior hypogastric plexus located in point of aortic bifurcation. It receives splanchnic nerves from lower lumbar and upper sacral sympathetic ganglia. Superior hypogastric plexus divides into right and left inferior hypogastric plexuses lower then promontorium. Inferior hypogastric plexus reaches the

organs and tissues of lesser pelvis with arterial branches from internal iliac artery. It innervates seminal vesicles, prostate (male) uterus, Fallopian tubes, vagina (female), also rectum, urinary bladder.

The pelvic portion of each sympathetic trunk is situated in front of the sacrum, medial to the anterior sacral foramina. It consists of four or five small sacral ganglia, connected together by interganglionic cords, and continuous above with the abdominal portion. Below, the two pelvic sympathetic trunks converge, and end on the front of the coccyx in a small ganglion, the ganglion impar.

  Gray rami communicantes pass from the ganglia to the sacral and coccygeal nerves. No white rami communicantes are given to this part of the gangliated cord, but the visceral branches which arise from the third and fourth, and sometimes from the second, sacral, and run directly to the pelvic plexuses, are regarded as white rami communicantes.

  The branches of distribution communicate on the front of the sacrum with the corresponding branches from the opposite side; some, from the first two ganglia, pass to join the pelvic plexus, and others form a plexus, which accompanies the middle sacral artery and sends filaments to the glomus coccygeum (coccygeal body).

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Parasympathetic nerves of the pelvis origin from nuclei in sacral segments S_II - S_IV of spinal cord. Preganglionic fibers [pelvic splanchnic nerves] pass to the terminal ganglia near organs. Postganglionic fibers innervate urinary bladder, reproductive organs, Lower half of descending colon, sygmoid colon and rectum.

The great plexuses of the sympathetic are aggregations of nerves and ganglia, situated in the thoracic, abdominal, and pelvic cavities, and named the cardiac, celiac, and hypogastric plexuses. They consist not only of sympathetic fibers derived from the ganglia, but of fibers from the medulla spinalis, which are conveyed through the white rami communicantes. From the plexuses branches are given to the thoracic, abdominal, and pelvic viscera.

The Pelvic Plexuses—The pelvic plexuses supply the viscera of the pelvic cavity, and are situated at the sides of the rectum in the male, and at the sides of the rectum and vagina in the female. They are formed on either side by a continuation of the hypogastric plexus, by the sacral sympathetic efferent fibers from the second, third, and fourth sacral nerves, and by a few filaments from the first two sacral ganglia. At the points of junction of these nerves small ganglia are found. From these plexuses numerous branches are distributed to the viscera of the pelvis. They accompany the branches of the hypogastric artery.

  The Middle Hemorrhoidal Plexus (plexus hæmorrhoidalis medius) arises from the upper part of the pelvic plexus. It supplies the rectum, and joins with branches of the superior hemorrhoidal plexus.

Lower half of right sympathetic cord.

 

  The Vesical Plexus (plexus vesicalis) arises from the forepart of the pelvic plexus. The nerves composing it are numerous, and contain a large proportion of spinal nerve fibers. They accompany the vesicle arteries, and are distributed to the sides and fundus of the bladder. Numerous filaments also pass to the vesiculæ seminales and ductus deferentes; those accompanying the ductus deferens join, on the spermatic cord, with branches from the spermatic plexus.

  The Prostatic Plexus (plexus prostaticus) is continued from the lower part of the pelvic plexus. The nerves composing it are of large size. They are distributed to the prostate vesiculæ seminales and the corpora cavernosa of the penis and urethra. The nerves supplying the corpora cavernosa consist of two sets, the lesser and greater cavernous nerves, which arise from the forepart of the prostatic plexus, and, after joining with branches from the pudendal nerve, pass forward beneath the public arch.

  The lesser cavernous nerves (nn. cavernosi penis minores; small cavernous nerves) perforate the fibrous covering of the penis, near its root.

  The greater cavernous nerve (n. cavernosus penis major; large cavernous plexus) passes forward along the dorsum of the penis, joins with the dorsal nerve of the penis, and is distributed to the corpora cavernosa.

 

 

 

  The Vaginal Plexus arises from the lower part of the pelvic plexus. It is distributed to the walls of the vagina, to the erectile tissue of the vestibule, and to the clitoris. The nerves composing this plexus contain, like the vesical, a large proportion of spinal nerve fibers.

  The Uterine Plexus accompanies the uterine artery to the side of the uterus, between the layers of the broad ligament; it communicates with the ovarian plexus.

Prepared by

Assistant Galytsa-Harhalis O.Ya.

 

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