1 xiphisternal junction: between body of sternum and xyphoid process; small sternal portion of diaphragm attaches here
2 costal margin: palpable upturned medial ends of costal cartilages 7 to 10 which are joined
3 pubic symphysis: meeting of 2 pubic bones; lowest limit of anterior abdominal wall
4 pubic crest: palpable crest of pubic bones just lateral to pubic symphysis
5 pubic tubercle: pump at lateral ends of pubic crest; inferior medial attachment site of inguinal ligament
6 inguinal ligament: formed by external oblique muscle folding back under itself at its inferior edge; stretches from pubic tubercle to anterior superior iliac spine
7 anterior superior iliac spine: at anterior edge of the iliac crest
8 tubercle for the crest: most lateral point of iliac crest
9 superficial layer of superficial fascia (Camper's fascia): fatty layer; merges with superficial fascia of thigh
10 superficial epigastric vein: deep to Camper's fascia and runs inferiolaterally; anastomoses with lateral thoracic vein and drains into great saphenous vein of leg
11 membranous deep layer of superficial fascia (Scarpa's fascia): fuses with deep fascia of abdomen superiorly and fascia lata just inferior to inguinal ligament; continuous with superficial fascia of perineum (Colle's fascia)
12 fascia lata: deep fascia of thigh
13 anterior cutaneous nerves: terminal twigs of ventral rami of T7 to L1; come through rectus sheath a few centimeters lateral to linea alba and run a short distance just deep to superficial fascia; anterior cutaneous branch of the iliohypogastric nerve (L1) is the most inferior of these
14 lateral cutaneous nerves: emerge between interdigitations of external oblique muscle with the serratus anterior and latissimus dorsi (T7 to T12); there is a small poster branch and a larger anterior branch of each. Anterior branches descend in the superficial fascia in line with the fibers of the external oblique
15 superficial inguinal ring: opening in aponeurosis of external oblique; between pubic crest and medial and lateral crura
16 deep (internal) inguinal ring: slit in transversalis fascia lateral to inferior epigastric artery
17 lateral (inferior) crus: portion of aponeurosis of external oblique that attaches to the pubic tubercle; at the inferior border of the inguinal canal
18 medial (superior) crus: portion of aponeurosis of external oblique that attaches to pubic crest medial to pubic tubercle; superior border of inguinal canal
19 intercrural fibers: lateral to superficial inguinal ring; run between lateral and medial crura to prevent spreading
20 lacunar ligament: medial part of inguinal ligament reflected horizontally back and attached to the pecten pubis
Conjoint Tendon =The fusion of the lower most fibers of the aponeuroses of internal oblique and transversus abdominus.
*The conjoint tendon (internal oblique & transversus abdominis) inserts in the pectin pubis and pubic crest (Insertion point for above muscles).
*The conjoint tendon reinforces the inguinal canal posterior wall medially and arches over spermatic cord as it lies in inguinal canal forming the inguinal canal roof (superior wall).
Fascia Transversalis =A somewhat transparent internal investing layer, lines most of abdominal wall; fuses posteriorly w/ anterior lamina of thoracolumbar fascia; covers deep surface of transversus abdominis muscle & its aponeurosis & is continuous from side to side, deep to the linea alba.
*Includes: Diaphragmatic fascia on diaphragm
Psoas fascia on psoas major muscle
Iliac fascia on iliacus muscle
Femoral sheath formed w/ iliac fascia in thigh
*The internal spermatic fascia (the innermost of 3 coverings of the spermatic cord) is formed from fascia transversalis.
*The deep ring of the inguinal canal is deep to fascia transversalis.
*The inguinal canal posterior wall is formed by fasca transversalis.
*The testes develop in the lumbar regions deep to transversalis fascia and then pass through the inguinal canals into the scrotum.
Inferior epigastric = Inferior epigastric runs superiorly in transversalis fascia until it reaches the arcuit line and enters rectus sheath.
*Inferior epigastric artery & vein branches off external iliac artery & vein; Inferior epigastric artery anastamoses with superior epigastric artery forming an alternative pathway to lower extremities & abdomen; Cremasteric artery arises from inferior epigastric artery (in spermatic cord; supplies cremasteric muscle & spermatic cord coverings).
*Inferior epigastric forms the lateral umbilical ligaments
*Inferior epigastric arteries are important in defining inguinal hernias. A hernia sac passes either medial to the inferior epigastric artery (thru the inguinal triangle; = direct hernia; most often in old men), or the hernia sac passes lateral to the inferior epigastric artery (outside of the inguinal triangle; = indirect hernia; in males, deep ring; most common hernia in male infants.) **Inguinal or Hesselbach=s triangle boundaries are (1.)lateral edge rectus abdominal, (2.)inguinal ligament, and (3.)inferior epigastric artery.
Superior epigastric =Superior epigastric artery arises from internal thoracic artery. It enters the rectus sheath superiorly, just inferior to 7th costal cartilage.
*Superior epigastric artery anastomoses with inferior epigastric, anterior branches of subcostal arteries, and anterior & collateral branches of posterior intercostals.
Rectus sheath:=Strong, incomplete fibrous component of rectus abdominis
muscle; consists of aponeurosis of 3 muscles (external oblique, internal oblique, transversus abdominis) forming around/ surrounding the rectus abdominus muscle.
*Forms in peculiar way (Reason why hernias are common below arcuate line):
-Below arcuate line, all aponeurosis are posterior--back door is open; if enough force, gut can be pushed through.
-Superiorly (above umbilicus), muscles split/are on both sides of aponeurosis:
Transversus abdominis forms posterior wall.
Internal oblique slits into 2 laminae and surrounds
(to form part of both the anterior & posterior wall.)
External oblique forms anterior wall.
Posterior layer/wall =(of rectus sheath) is formed deep to rectus abdominis by the aponeurosis of the transversus abdominis muscle and the aponeurosis of half of the internal oblique muscle; it ends at the arcuit line at which point, all muscles inferiorly traverse in front of rectus abdominis.
Arcuit line:=A crescentic border @ the inferior limit of the posterior wall
of the rectus sheath; midway between umbilicus & pubic crest. Inferiorly, the 3 flat muscles all pass anterior to rectus abdominis.
Linea alba:=The fibers of the anterior & posterior walls of the rectus
sheath interlace in the anterior median line to form a complex tendinous raphe (intermixture of aponeurotic fibers of the obliques and transverse abdominal muscles.); a median, white fibrous line/band, indicated by a vertical skin groove in muscular individuals; the linea alba extends from the xiphoid process thru the umbilicus to the pubic symphysis and divides right & left abdomen. It is wider superior to the umbilicus.
*A verticle line through linea alba forms the median plane.
*Median hernias occur through defects in linea alba through which extraperitoneal fat &/or omentum protrude.--these are associated w/ middle age & obesity and, when occuring in the epigastric region, are called epigastric hernias.
*The lina alba is an insertion point for the external oblique, the internal oblique, and the transversus abdominis.
*The pyramidalis muscle tenses the linea alba.
Transversalis fascia: (see AFascia transversalis@ above.)
Extraperitoneal fat=Layer of fat in the anterior abdominal wall, between the fascia transversalis layer and (the deeper) peritoneal layer.
*Extraperitoneal fat evaginates into the inguinal canal where it separates tunica vaginalis (continuous w/ the abdominal peritoneum) and internal spermatic fascia (continuous with fascia transversalis).
Peritoneum: =Mesothelial membrane forming the abdominal sacs; serous.
Parietal part =lines abdominal & pelvic walls
Visceral part =lines viscera (organs)
*Peritoneal cavity: The space between the parietal and visceral peritoneum; (contains more liquid than in parietal & pericardial cavities to allow peristalsis (movement) w/o fiction.)
*Peritoneal reflections: Peritoneum reflected from one area to another (ie. body wall to organ/organ to organ.)
May be called: omenta = apron
Mesentaries = apron w/o free edge or ligaments
*Intraperitoneal: (inside peritoneum) organ that is almost completely covered by peritoneum, except for the small area where the mesentery is attached
*Retroperitoneal: (dorsal to/behind peritoneum) organ that is only covered w/ peritoneum on its anterior surface; no mesentary, one surface touching abdominal wall.
*Peritoneal fold: an elevation of peritoneum w/ a free edge, usually raised by an underlying blood vessel or its ligamentous remains(ie. lateral , medial, and median umbilical folds)
*Tunica vaginalis (in spermatic cord) arises from peritoneum.
*Blood supply to peritoneum: vessels of parietal part are via vessels from abdominal wall; vessels to visceral part are from vessels to organs.
*Nerves to peritoneum: From nerves of body wall T7 - L1; Vasomotor from sympathetics. Visceral part is insensitive to pain but parital part gives acute localized pain
Falciform ligament =A large, membranous median fold/peritoneal ligament superior to umbilicus which passes from deep surface of superior half of anterior abdominal wall to liver & diaphragm. It is the remnant of the embyological ventral mesentary that attaches the liver to the ventral body wall.
*The right lobe of the liver is the attachment point of the falciform ligament. The quadrate lobe is located between the falciform ligament and the gall bladder.
Ligamentum teres=The free edge of the falciform ligament. It is the remnant of the umbilical vein (obliterated umbilical vein).
External Oblique Muscle=Abdominal wall muscle whose fibers run inferoanteriorly. Medial fibers end at linea alba. External Oblique attaches to pubic crest. (See origin, insertion, & action in table below.)
*External oblique and half of internal oblique form the anterior layer of rectus sheath.
*External oblique aponeurosis forms the anterior wall of the inguinal canal and the medial crus (medial crus formed by the part of external oblique aponeurosis that diverges to attach to pubic bone & pubic crest medial to pubic tubercle).
*The inguinal ligament and superficial inguinal ring is aponeurosis of external abdominal oblique. External oblique muscle folds back on itself inferiorly to form inguinal ligament. The medial part of inguinal ligament is reflected horizontally back & attached to the pecten pubis, called the lacunar ligament. Some fibers of inguinal ligament cross the linea alba & attach to opp. pubic crest, called reflex inguinal ligament.
*External oblique aponeurosis also forms the superficial spermatic fascia of the spermatic cord.
Internal Oblique Muscle=Abdominal wall muscle whose fibers run superoanteriorly. Above the arcuit line, internal oblique aponeurosis splits into 2 laminae and surrounds rectus abdominis (anterior & posterior walls of rectus sheath). The lower most fibers join with lower most fibers of transverse abdominis to form the conjoint tendon which inserts on pubic crest and pectin pubis. (See origin, insertion, & action in table below.)
*Inferior internal oblique fibers (conjoint tendon) arch over the spermatic cord as it lies in inguinal canal (superior wall/roof) and descend posterior to superficial inguinal ring to attach to the pubic crest & pecten pubis. The internal oblique muscle/conjoint tendon also helps to reinforce the inguinal canal both medially (posterior wall) and laterally (anterior wall).
*Within the inguinal canal, internal oblique muscle forms the cremasteric muscle and cremesteric fascia.
*The neurovascular plane lies between internal oblique and transversus abdominis muscles. Lower intercostal nerves, inferior intercostal arteries, subcostal arteries, and lumbar arteries pass from intercostal spaces and run within this plane. The deep circumflex iliac artery also runs between internal oblique and transversus abdominis parallel to the inguinal canal.
Transversus Abdominis=Innermost
Abdominal wall muscles whose fibers run horizontally, except for
inferior-most fibers which join with and run parallel to internal
oblique muscle (conjoint tendon). Transversus abdominis aponeurosis
forms the posterior wall of rectus sheath and the superior wall/roof
via the conjoint tendon of the inguinal canal. It also contributes to
the inguinal canal both medially (posterior wall) and laterally
(anterior wall).
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Subcostal nerve |
Flex & rotate trunk |
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fascia, anterior 2/3 iliac crest, lateral 2 inguinal ligament |
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1st Lumbar nerves |
Flex & rotate trunk |
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costal cartilages 7-12, thoracolumbar fascia, inner lip of iliac crest, outer/ lateral 1/3 of inguinalligament |
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Inferior 6 thoracic & 1st Lumbar nerves |
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Ligamentum teres: (See ligamentum teres above)
Median umbilical ligament =The fibrous remnant of the urachus that joined the fetal bladder to the umbilicus. The median umbilical ligament passes from the deep aspect of umbilicus vertically to the apex of the urinary bladder.
Medial umbilical ligament =obliterated umbilical arteries; the obliterated parts of the fetal umbilical arteries. The 2 medial umbilical ligaments ascend obliquely from lateral pelvis walls to the umbilicus.
Dartos:=A thin sheet of smooth muscle in the superficial fascia (Colles= fascia) of the scrotum. Dartos muscle fibers are a continuation of abdominal subcutaneous (below the skin) fat and, as such, are attached directly to skin. Contraction of Dartos muscles causes the scrotum to wrinkle when cold to help regulate heat loss. The combination of Colles fascia and Dartos muscle is called Dartos tunic.
Gubernaculum testis =In the fetus, a ligament that extends from the testis through the anterior abdominal wall and inserts into the internal surface of the scrotum. The gubernaculum indicates the site of the inguinal canal. Later, the processus vaginalis (a diverticulum of peritoneum) follows the gubernaculum, evaginating the anterior abdominal wall to form the inguinal canal. The testes usually enter the inguinal canals just before birth and pass inferomedially through them into the scrotum. The processus aginalis then obliterates leaving the tunica vaginalis. The derivative of the gubernaculum in the adult is the scrotal ligament.
Constituents of the Spermatic Cord
testicular artery: long, slender vessel arising from the anterior aorta (L2); the main vessel supplying the testis and epididymis
pampiniform venous plexus/pampiniform plexus of veins: up to 12 veins leaving the posterior surface of the testis anastomose to form this large, vine-like plexus; forms a large part of the spermatic cord, surrounds the ductus deferens and arteries in the spermatic cord; located within the internal spermatic fascia and end in the testicular vein
autonomic nerve fibers: sympathetic fibers on the arteries and sympathetic and parasympathetic fibers on the ductus deferens; include sensory nerves (pain fibers, e.g. when testis is squeezed or injured); run with blood vessels
lymph vessels: lymph vessels draining the testis and immediately associated structures pass superiorly in the spermatic cord; end in lumbar and preaortic lymph nodes between common iliac and renal veins
external spermatic fascia: the thin outermost covering of the cord; from the aponeurosis of the external oblique muscle; attached superiorly to the crura of the superficial inguinal ring; continuous with the deep fascia covering the external oblique muscle
cremasteric fascia: the middle layer of the covering of the cord; areolar, contains loops of cremaster muscle; muscle fibers and fascia from the internal oblique muscle and its fascia
internal spermatic fascia: filmy innermost covering of the spermatic cord; from the transversalis fascia
deferent artery: artery of the ductus deferens; arises from the inferior vesical artery and anastomoses with the testicular artery near the testis; accompanies the ductus deferens throughout its course
inferior epigastric vessels: branches of the external iliac vessels; artery supplies the anterior abdominal wall; anastomose with the superior epigastric vessels; artery forms lateral boundary of inguinal triangle; ductus deferens hooks around the lateral side of the vessels in inguinal canal
tunica vaginalis testis: closed serous sac (potential space) of peritoneal origin; two layers--parietal is adjacent to internal spermatic fascia, visceral is adherent to testis and epididymis; covers the anterior, medial, and lateral surfaces of the testis, but NOT the posterior surface
tunica albuginea: dense, white connective tissue capsule of the testis
seminiferous tubules: site of spermatogenesis; coiled tubules within testis
rete testis: a network of canals in testis; connect seminiferous tubules to efferent ductules, which in turn, connect the rete testis to the head of the epididymis
epididymis: comma-shaped structure attached to the superior and posterolateral surface of the testis; site of final stages of sperm maturation
duct of the epididymis: highly convoluted duct within the epididymis; continuous with the ductus deferens; makes up the body of the epididymis
ductus (vas) deferens: duct which transports sperm from the epididymis to the ejaculatory duct for expulsion into the prostatic urethra; hard and cord-like in consistency; deferent artery feeds it and runs with it; continuous with the tail of the epididymis
sinus of the epidiymis: space separating the testis from the body of the epididymis
head of the epididymis: superior expanded part of the epididymis; composed of the lobules of the epididymis, which are the coiled ends of the efferent ductules of the testis
efferent ductules: ducts between the rete testis and the epididymis; transmit sperm from the testis to epididymis
Peritoneum- The mesothelial membrane forming the abdominal sacs. The parietal peritoneum lines the abdominal and pelvic walls. The visceral peritoneum lines the organs. The peritoneal cavity is defined as the space between the parietal and visceral peritoneum (there is more liquid in the peritoneal cavity than in the pleural cavity). The peritoneal cavity lubricates and allows the viscera to move. In the embryo, peritoneum is a large sac that lines the abdominal cavity. The beginnings of viscera are outside the sac. As they develop, they push into the peritoneum in varying degrees. Some organs are covered with peritoneum on only the anterior surface (retroperitoneal), while some are completely covered with peritoneum except for the small area where the mesentery attaches (intraperitoneal). Damage to the mesothelium forming the peritoneum could result in the peritoneal layers adhering to each other. This could interfere with the normal movement of viscera. Innervation: parietal: phrenic, lower intercostal, subcostal, iliohypogastric, ilioinguinal. Visceral: visceral nerves along autonomic pathways (relatively insensitive).
Omenta: A double-layered sheet or fold of peritoneum.
Lesser Omentum: Lies posterior to the left lobe of the liver and connects the lesser curvature of the stomach (hepatogastric ligament) and the proximal part of the duodenum (hepatoduodenal ligament) to the liver. The opening is the epipolic foramen. The lesser omentum is cut off and isolated from the greater sac due to the embryonic rotation of the stomach.
Greater Omentum: Connects the stomach with the diaphragm, spleen and transverse colon, passing inferiorly as far as the pelvis, then looping back on itself overlying and attaching to the transverse colon. The greater omentum hangs down from the greater curvature of the stomach and is filled with fat. It is a doulbe-layered peritoneal fold which usually fuses during the fetal period, therefore it is made of four layers of peritoneum.
Mesentery: A double layer of peritoneum that encloses an organ and attaches it to the abdominal wall. Vessels and nerves travel to the organ between the two layers that comprise the mesentery. The area between these layers also consists of connective tissue containing fat cells and lymph nodes. Mesentery makes an organ mobile. Retroperitoneal and intraperitoneal organs are less mobile due to their lack of mesentery.
Peritoneal ligaments: double layer of peritoneum. Connects an organ with another organ or the abdominal wall; may contain blood vessels or remnants of blood vessels. The greater omentum is divided into three peritoneal ligaments: gastrocolic ligament: apronlike part attached to the transverse colon, gastrosplenic ligament: left part that connects the spleen to the greater curvature of the stomach, gastrophrenic ligament: superior part with attaches to the diaphragm.
Right Lobe of Liver: demarcated by the gallbladder fossa and the fossa of the inferior vena cava on the visceral surface of the liver and by an imaginary line over the diaphragmatic surface that runs from the fundus of the gallbladder to the inferior vena cava.
Left Lobe of Liver: includes the caudate lobe and most of the quadrate lobe. Is separated from the caudate and quadrate lobes by the fissure for the ligamentum teres and the fissure for the ligamentum venosum and on the diaphragmatic surface by the attachment of the ligamentum teres.
Falciform ligament:
á connects the liver with the anterior abdominal wall and the diaphragm
á double-layered, formed from ventral mesentery
á its two layers separate from each other at the superior end, thereby exposing the bare area of the liver
Gallbladder:
á found along the right edge of the quadrate lobe of the liver, where it lies in the gallbladder fossa
á cystic duct runs from the gallbladder and joins common hepatic to form bile duct
á Function: concentrates and stores bile secreted by liver
á Parts: fundus, body, neck
Stomach:
á distensible part of digestive system between esophagus and small intestine
á lesser curvature and greater curvature
á 4 parts: cardia, fundus, body, pyloric part (pyloric antrum and pyloric canal), pylorus
á arterial supply: left gastric a., right gastric a., right and left gastro-omental a., short gastric a.
á Venous drainage: veins follow arteries and drain into portal system
á Lymphatic drainage: 4 areas of lymphatic drainage, all of which drain into celiac lymph nodes
á Innervation: parasympathetic from anterior and posterior vagal trunks, sympathetic from the celiac plexus
Spleen:
á Biggest mass of lymphoid tissue in the body
á Arterial supply: splenic a and its branches, which are end arteries
á Venous drainage: splenic vein
á Lymphatic drainage: pancreaticosplenic lymph nodes
á Innervation: celiac plexus
Gastrolienal/gastrosplenic ligament:
á The left part of the greater omentum; connects spleen to the greater curvature of the stomach
Cecum:
á Broad blind pouch that is the first part of the large intestine; between ileum and ascending colon
á Does not have a mesentery
Ascending colon:
á Runs along the right side of the abdominal cavity, between the cecum and the right colic flexure
á retroperitoneal
á Arterial supply: ileocolic and right colic a.
á Venous drainage: ileocolic and right colic v.
á Lymphatic drainage: paracolic and epicolic lymph nodes, then to superior mesenteric lymph nodes
á Innervation: celiac and superior mesenteric ganglia
Transverse colon:
á Extends from right colic flexure to left colic flexure
á Its mesentery is called the transverse mesocolon
á Arterial supply: middle colic a., right and left colic a.
á Venous drainage: superior mesenteric v.
á Lymphatic drainage: superior mesenteric lymph nodes
á Innervation: superior mesenteric plexus, inferior mesenteric plexus
Descending colon:
á Runs between the left colic flexure and the sigmoid colon
á Retroperitoneal
á Arterial supply: left colic a., superior sigmoid a.
á Venous drainage: inferior mesenteric vein
á Lymphatic drainage: intermediate colic lymph nodes, then to inferior mesenteric lymph nodes
á Innervation: sympathetic from lumbar part of sympathetic trunk and superior hypogastric plexus, parasympathetic from pelvic splanchnic nerves
Sigmoid colon:
á S-shaped part of large intestine between the descending colon and the rectum that stores feces
á Long mesentery, so very movable
á Arterial supply: sigmoid arteries (branches of the inferior mesenteric a.)
á Venous drainage: inferior mesenteric vein
á Lymphatic drainage: intermediate colic lymph nodes, then the inferior mesenteric lymph nodes
á Innervation: sympathetic from lumbar part of sympathetic trunk and superior hypogastric plexus, parasympathetic from pelvic splanchnic nerves
Alimentary Canal- the digestive tract from the mouth to the anus.
Pylorus- distal sphincter of the stomach opening into the duodenum. Pylorus opens at intervals allowing acidic chyme to enter the duodenum. Opening relies primarily on greater pressure within the stomach as opposed to the duodenum.
Lesser Curvature- continuous with the right border of the esophagus. Forms the smaller, concave border of the stomach.
Hepatogastric Ligament- superior portion of the lesser omentum, connecting the lesser curvature of the stomach to the liver.
Hepatoduodenal Ligament- inferior portion of the lesser omentum, connecting the duodenum to the liver.
Greater Curvature- continuous with the left border of the esophagus. Forms the convex border of the stomach. 4 to 5 times larger than the lesser curvature.
Gastrocolic- portion of the greater omentum that connects the colon with the stomach.
Gastrosplenic- portion of the greater omentum to stomach and spleen.
Duodenum- first and "fixed" part of the small intestine- from pylorus of stomach, continuous with jejunum. C-shaped and wrapped around the head of the pancreas. Celiac arterial supply.
Jejunum- follows duodenum. Proximal 2/5 of the "mobile" small intestine. As compared to the ileum: has more plicae circularis, thicker walls, more arcades, less omental fat. Superior mesenteric arterial supply.
Ileum- Inferior 3/5 of the "mobile" part of the small intestine. See above for comparison with the jejunum. Superior mesenteric and ileocolic arterial supply. (hint- "ileum" vs "ilium"- the ileum is twisted and better represented with an "e" in its name.)
Duodenojejunal junction- connection between the immobile duodenum and the mobile jejunum.
Ileocecal orifice or junction- where the ileum and cecum meet. Beginning of the large intestine.
Root of the mesentery- runs obliquely from left side around L2 toward cecum. Attached to the posterior abdominal wall. About 8-12 inches long.
Intestinal border of the mesentery- jejunoileal aspect of the mesentery. Runs the entire length of the small intestine. Is 18-21 feet long.
Rectum- Lower part of the large intestine. Extends from S3 to the tip of coccyx. Has three indentations, one on right side, two on left.
Anal canal- terminal end of the alimentary canal. About 1.5 inches long. Includes internal and external anal sphincters.
Vermiform appendix- worm shaped appendage continuous with the blind pouch of the cecum.
Right colic or hepatic flexure- bend in the large intestine from the ascending to the transverse colon.
Left colic or splenic flexure- bend in the large intestine from the transverse to the descending colon.
Phrenicocolic ligament- ligament from the left colic or splenic flexure to the diaphragm. Forms a shelf to support the spleen.
transverse mesocolon
sigmoid mesocolon
teniae coli
anterior tenia
haustra
appendices epiploicae
diaphragmatic surface
visceral surface
porta hepatis
gallbladder
hepatoduodenal ligament
hepatic artery
portal vein
bile passages
omental foramen
omental bursa or lesser sac
anterior wall, lesser omentum
inferior recess
superior recess
splenorenal ligament
1. Gastrosplenic ligament: Part of the greater omentum, connects spleen to the greater curvature of the stomach. Also called Gastrolienal. See Netters 255-6.
2. Pedicle: The stalk that is formed by the splenorenal and gastrospenic ligaments. Together they suspend the spleen between the kidney and stomach. The "pedicle" transmits blood vessels to and from the hilus of the spleen.
3. Peritoneal Attachments of the liver: The liver is amost entirely covered with Peritoneum. The falciform ligament connects the liver to the anterior abdominal wall and to the diaphragm. The coronary ligament surrounds the bare area of the liver. This ligament is continuous with the right and left triangular ligaments.
4. Subphrenic recesses: Space between liver and diaphragm. The right and left subphrenic recesses are separated by the falciform ligament.
5. Bare Area: Area of the liver that is not covered by peritoneum. This "naked" area is located superiorly and posteriorly on the right lobe and is in direct contact with the diaphragm. The inferior vena cava runs along the left part of the bare area.
6. Coronary Ligament: Surrounds bare area of the liver. Continuous with the Left and Right triangular ligaments. The coronary ligament is basically peritoneal reflections surrounding the bare area.
7. Left Triangular Ligament: The peritoneal fold attaching the left tip of the left hepatic lobe to the diaphragm. Continuous with the coronary ligament. (There is also a Right Triangular Ligament)
8. Hepatorenal Ligament: This is just another name for the inferior part of the coronary ligament. It is peritoneum which is reflected onto the diaphragm of the right kidney so this part of the coronary ligament is sometimes called the hepatorenal ligament.
9. Hepatorenal Pouch or Recess: A potential peritoneal space which is inferior to the hepatorenal ligament (see above). This pouch is bounded by the liver, right kidney, colon and duodenum. Also called pouch of Morrison.
10. Peritoneal Gutters: There are four. These gutters conduct materials (blood, bile, etc.) from one point of the peritoneal cavity to another. They are formed by the mesenteries of the small intestine and the ascending and descending colons.Important clinically because of they can help spread intraperitoneal infections. (See dissector page 61 for a picture).
Listed below.
11. Right Lateral (Paracolic) Gutter or Sulcus: Runs to the right of the ascending colon
12. Left Lateral (Paracolic) Gutter: Runs to the left of the descending colon. Closed at the top (cranially) by the phrenicocolic ligament.
13. Gutter to the Right of the Mesentery: Closed cranially and caudally.
14. Gutter to the Left of the Mesentery: Opens widely into the pelvis (See dissector page 61).
15. Paracolic Gutters: (See above)
16. Heptaduodenal Ligament: The part of the lesser omentum between the liver and the duodenum. Continuous with the hepatogastric ligament. Terminates in a free border on the right.
17. Hepatic Artery: Common hepatic artery is a branch off the celiac trunk. It bifurcates into the proper hepatic artery and the gastroduodenal artery. Supplies liver, stomach, gall bladder and duodenum.
18. Portal Vein: Carries venous blood from the abdominal portion of the GI tract, the spleen and pancreas to the liver for metabolic processing. By definition the portal vein begins at the junction of the splenic vein and the superior mesenteric vein. (See dissector page 63)
19. Bile Duct: The common bile duct drains bile from both the liver and the gallbladder. Formed by the cystic and hepatic ducts.
20. Cystic Duct: Comes from the neck of the gall bladder and joins the hepatic duct to form the common bile duct.
Common hepatic duct - 4 cm long; formed by junction of right and left hepatic ducts; later joined by cystic duct from gallbladder to form common bile duct
Right and left hepatic ducts - join at base of liver to form common hepatic duct
Autonomic nerve fibers of gallbladder - nerves pass along cystic artery from celiac plexus (sympathetic--located at celiac trunk), the vagus nerve (parasympathetic), and right phrenic nerve (sensory)
Hepatic lymph nodes - scattered along hepatic vessels and ducts in the lesser omentum
Hepatic artery proper - common hepatic artery after it gives off gastroduodenal artery; ascends free edge of lesser omentum with portal vein and bile duct
Common hepatic artery - right branch of celiac trunk
Celiac trunk - 1st anterior aortic branch below the diaphragm; gives off three branches
Left hepatic artery - left branch off of common hepatic artery near base of liver
Right hepatic artery - right branch off of common hepatic artery near base of liver
Cystic artery - branch off of right hepatic artery leading to gallbladder
Splenic artery - left inferior branch of celiac trunk; runs along pancreas, underneath stomach to spleen
Left gastric artery - left superior branch of celiac trunk; runs along lesser angle of stomach
Right gastric artery - branch off of common hepatic artery running to the lesser angle of stomach (anastomoses with left gastric artery)
Right gastroepiploic artery - Branch off of gastroduodenal artery that runs along greater angle of stomach;
Gastroduodenal artery - passes posterior to gastroduodenal junction to give off right gastroepiploic and pancreaticoduodenal arteries
Left gastroepiploic artery - Branch off of splenic artery running along greater angle of stomach to anastomose with right gastroepiploic artery
Splenic vein - passes over aorta from left side inferior to celiac trunk to join superior mesenteric vein; junction forms hepatic portal vein
Superior mesenteric vein - runs along (and anterior to) inferior vena cava to join splenic vein to form hepatic portal vein running to liver
Inferior mesenteric vein - branch joining the splenic vein on the left side of the aorta which runs down to the colon
Gastric veins - right and left branches join hepatic portal vein; drain lesser angle of stomach
Superior mesenteric artery - second main anterior branch off of aorta (just below celiac trunk)
Superior mesenteric plexus of nerves - nerve plexus just superior to SMA
intestinal arteries- from the major vessels, the arteries run together to form arcades (arches of arteries), which then give off vessels that supply the intestine. Arcades are not very evident in the large intestine, mostly the jejunum and ileum.
vasa recta-the straight vessels that pass to the intestine from the arcades. They do not anastamose in the mesentery, but there are extensive anastamoses in the wall of the intestine.
ileocolic artery- from the superior mesenteric artery (SMA) gives off an ileal branch and a colic branch that supply the distal ileum and cecum (and appendix) respectively. The ileal branch anastamoses with the the ileal branches of the SMA.
right colic artery- arises either directly from the SMA or from the ileocolic artery. It supplies the ascending colon and anastamoses with the colic branch of the ileocolic artery.
middle colic artery- arises from the SMA and supplies the transverse colon.
inferior mesenteric artery- arises from the aorta below the SMA and celiac trunk. It supplies the distal part of the transverse colon, the descending colon, the sigmoid colon, and part of the rectum.
left colic artery-arises from the inferior mesenteric artery (IMA) and supplies primarily the descending colon. Also anastamoses with the middle colic artery to form the marginal artery which helps to supply the transverse colon.
sigmoid arteries- from the IMA, supply the sigmoid colon.
superior rectal artery- from the IMA, but usually looks like the last branch of sigmoid arteries, supplies the rectum (there are also a middle and inferior rectal arteries, but they arise elsewhere).
inferior mesenteric vein- roughly follows the IMA and drains the same structures supplied by the IMA
inferior mesenteric nodes- located near the IMA, but unlikely to be seen on any of our dissections (good thing to ask about). Receive lymph from the distal 1/3 of the transverse colon, the descending colon, and the sigmoid colon.
superior rectal vein- drains the internal rectal venous plexus and the superior portion of the external rectal venous plexus. Anastamoses extensively with both plexi that drain the rectum. Hence, blockage of the portal vein can cause intestinal venous flow to back into these plexi, causing hemmorhoids.
mesentery of the sigmoid colon- a long mesentery that allows considerable movement of the sigmoid colon. It has a V-shaped attachment near the external iliac vessels (superiorly) and the common iliac vessels and anterior sacrum (inferiorly).
descending colon- intraperitoneal from the transverse colon (left colic (or splenic) flexure)to the sigmoid colon.
phrenicocolic ligament- attaches the left colic flexure to the diaphragm immediately superior to it. Basically, it*s a horizontal fold of hte peritoneum.
spleen - large, soft (but not in a cadaver) vascular lymphatic organ in the upper left quadrant. Between the layers of the dorsal mesentery, it contacts the posterior wall of the stomach and is attached to the greater curvature of the stomach by the gastrosplenic ligament and to the left kidney by the splenorenal ligament. Usually in a position near the 9th and 11th ribs on the left side.
esophagus - if you don*t know what this is, I*m worried about you. Transports boli of food from the pharynx to the stomach through the diaphragm.
duodenojejunal junction or flexure - where the duodenum meets the jejunum. At this point, the small intestine moves intraperitoneal from being retroperitoneal. The small intestine meets the body of the pancreas at this point and makes a sharp anterior bend. It is about 2-3 cm left of the medial plane.
suspensory muscle of the duodenum - (Ligament of Treitz) supports the duodenojejunal flexure. Superior part is striated muscle, middle part is elastic tissue, inferior part is smooth muscle. Attached to the ascending duodenum and then splits to attach to the right crus of the diaphragm, close to the esophageal opening, and to the connective tissue around the celiac trunk. Widens the angle of the duodenojejunal flexure to facilitate movements of the intestinal contents.
1. PANCREAS elongated digestive gland, lies transversely across posterior abdominal wall, posterior to stomach.
Exocrine: pancreatic juice
Endocrine: glucagon, Insulin
2. Inferior Vena Cava: is formed on the right side of L5 by the union of the two common iliac veins, below the bifurcation of the aorta. Is longer than the abdominal aorta, and ascends at the right side of the aorta. Passes through the opening for the inferior vena cava in the central tendon of the diaphram at the level of T8, and enters R. atrium of heart. Recieves the right gonadal, suprarenal, and inferior phrenic veins. On the left side these veins usually drain into the left renal vein. Also recieves the three (left, middle and right) hepatic veins. Middle and left veins frequently unite about 1cm before entering vena cava.
3. Esophageal and Gasric Veins: part of portal -systemic anastamosis. Esophageal tributaries of L. gastric vein anastamose with esophageal v., which drains into systemic Azygos veins. If portal hyper tension occurs: ESOPHAGEAL VARICES - dilation of veins, can bleed due to rupture. Severe.
4. Pancreaticosplenic nodes
5.BILE DUCT formed by union of cystic duct of gall bladder and hepatic duct of liver, descends in long fissure in posterior part of head of pancreas to duodenum.
6. Major duodenal papilla: place where united pancreatic and bile ducts (hematopancreatic ampulla) enter into the duodenum.
7. Main pancreatic duct: begin at tail, unites with accessory gland in uncinate/head region - joins with bile duct to enter duodenum at Ampulla of Vater.
8. Sphincter of Oddi: Around hematopancreatic ampulla, controls flow of bile and pancreatic juice to duodenum.
9. Hood like plica: fold of duodenum surrounding maj. duodenal papilla.
10. Four lobes of liver: fuctionally independent R & L lobes, each have own blood supply from hepatic artery and portal vein, and its own veins and biliary drainage. L lobe includes Caudate and most of Qaudrate lobes.
11. Right Sagittal Fossa: for gall bladder ( located between quadrate lobe and maj. Part of right lobe) and Inferior vena cava (located between caudate lobe and maj. Part of right lobe).
12. Left Sagittal Fissure: deep fissure containing ligamentum teres (l. Umbilical v.) and ligamentum venosum (ductus venosus)
13. Transverse Fissure: Porta Hepatis: is a deep trans. Fissure on visceral surface, contains hepatic artery, branches of portal veins, hepatic duct, also hepatic nerve plexus and lymphatic vessels. Cross bar for "H".
14. Hepatic veins: formed by union of central veins in its lobules. Opens into Inf. Vena Cava, just inferior to diaphragm.
15.Hilus: indentation on medial border of kidney through which ureter, renal vessels, and nerves enter and leave the organ
16. Visceral Surface: inferior, posterior and to the left, seperated from diaphragmatic surface by inferior border.
17. Diaphragmatic surface: superior surface of liver covered by diaphragm. Liver seperated from diaphragm by part of peritoneal cavity: subphrenic recess
18. Plicae Circularis: circular folds of mucous membrane. When they stretch they increase surface area. Some in Duodenum, most in jejunum, almost none in ileum.
19. Ileocecal region: Ileum enters into cecum obliquely, partly envaginates into it, creating ileoceca valve: lips superior and inferior to orifice. It is a weak valve, with poorly developed muscle. Prevents reflux back into ileum. Frenula of valve: lips of valve meet medially and laterally, form ridge. When cecum distended frenula tighten, drawing lips closed.
20. Plicae semilunaris: Internal folds of mucosa of large intestine, related to Haustra sacculations of wall.
RETROPERITONEAL SPACE: the space occupied by retroperitoneal organs, ie. those w/a surface fused to the body wall - including, kidneys, pancreas, descending and ascending colons and the rectum.
Kidneys: RIGHT - superior pole @ transpyloric plane; LEFT - hilum @ transpyloric plane; invested by a firm, fibrous CAPSULE;
PERIRENAL FAT - fills the periphrenic space (between the capsule and the fibrous RENAL FASCIA);
PARARENAL FAT - overlies the renal fascia;
RENAL PELVIS - the collecting duct in the hilum into which drain the major calyces;
URETER - muscular, retroperitoneal tube that descend from the pelvis into the bladder; its ABDOMINAL PART descends along the psoas muscle and crosses in front of the common iliac; its PELVIC PART descends along the lateral pelvic wall, is crossed by the ductus deferens or uterine artery, then enters a postero-supero-lateral "corner" of the bladder.
LEFT TESTICULAR VEIN - drains into the left renal vein.
LEFT RENAL VEIN - drains left kidney into IVC.
RIGHT TESTICULAR (OR OVARIAN) VEIN - drains directly into IVC.
TESTICULAR ARTERIES - accompany ductus deferens into the scrotum; supply spermatic cord, epididymus, and testes; descend from aorta below renal branches.
OVARIAN ARTERIES - enter suspensory ligament of ovaries; anastomose w/ ovarian branch of uterine arteries; descend from aorta below renal branches.
LEFT SUPRARENAL VEIN - drains suprarenal gland; enters left renal vein.
RIGHT SUPRARENAL VEIN - enters directly into IVC
RIGHT RENAL ARTERY - feeds the right kidney; gives rise to inferior suprarenal and ureteric arteries.
TRANSVERSUS ABDOMINUS -
attachments: lateral 1/3 inguinal ligiment; iliac crest; thoracolumbar fascia; inner surface of lower costal cartilages; linea alba; pubic crest; pectineal line. action: compress abdomen, depress ribs.
innervation: inter & subcostals (T7-T12), iliohypogastric, ilioinguinal nerves (L1).
QUADRATUS LAMBORUM -
attachments: transverse processes L3-5; iliolumbar ligament; iliac crest, lower border of last rib, transverse processes L1-3.
action: depress rib 12, flex trunk laterally.
innervation: subcostal; L1-3.
PSOAS MAJOR -
attachments: t. processes, intervertebral disks and bodies of T12-L5; lesser trochanter.
action: flexes thigh and trunk.
innervation: L2-3.
12th rib
ribrous capsule
renal cortex
renal medulla
renal pyramids
renal columns
renal papillae
calyces minores
calyces majores
major calyces
renal pelvis
suprarenal (adrenal) glands
right adrenal gland
left adrenal gland
inferior phrenic arteries
aorta
renal arteries
abdominal aorta & its branches
branches to the GI tract & its 3
unpaired organs
branches to the 3 paired organs
branches to the walls
Bifurcation of abdominal aorta: The bifurcation creates the common iliac arteries. This occurs at L4.
Common iliac arteries: These arteries divide into the internal and external iliac arteries.
Portacaval system: This system allows the portal venous system to communicate with the systemic venous system. The main regions are: gastroesophageal, anorectal, paraumbilical, and retroperitoneal (Moore, pg. 209)
Iliacus: Muscle occupies the iliac fossa. It helps to flex the hip.
Iliopsoas: The combined muscle of the psoas major and iliacus. It is the main hip flexor.
Quadratus lumborum: A thick rhomboid muscle running from iliac crest to lumbar transverse process and rib 12. It flexes the vertebral column.
Transversus abdominis: The innermost flat muscle in the anterolateral abdominal wall.
Nerves of the Posterior Abdominal Wall: The nerves are derived from the vental rami of T12- L5. The nerves include:
Subcostal (T12) : Supplies anterior abdominal wall inferior to umbilicus but superior to pubic symphysis
Iliohypogastric (L1): Supplies skin of gluteal region and skin of hypogastric region
Ilioinguinal (L1): Supplies skin of groin and scrotum or labum majus
Genitofemoral (L1,L2): It supplies skin inferior and medial to the inguinal ligament and the cremaster muscle.
Lateral cutaneous nerve (L2, L3): Supplies the lateral aspect of the thigh with sensory fibers.
Femoral nerve (L2-L4): Supplies motor and sensory innervation to the anterior and medial thigh.
Obturator nerve (L2-L4): Supplies adductor muscles of the thigh
Lumbosacral trunk: It is composed of the ventral rami of L4 and all of L5. It contributes to the sacral plexus.
Sympathetic Trunk: Supplies the posterior abdominal wall before entering the pelvis.
Autonomic nerve supply of the abdomen: The abdomen is supplied by the following nerves and plexi: Thoracic splanchnic nerves, greater splanchnic nerve, lesser splanchnic nerve, least splanchnic nerve, intermesenteric plexus, superior hypogastric plexus, and inferior hypogastric plexus.
Lumbar plexus: Composed of the ventral rami of L1 - L4. The largest and most important branches are obturator and femoral nerves.
Diaphragm:
- the dome shaped muscular layer separating the thorax from the abdomen
- the principal muscle of respiration
- consists of a peripheral muscular layer and a central aponeurotic central tendon
- attached to inferior margin of thoracic cage and superior lumbar vertebrae.
Sternal Part:
- two small muscular slips attached to posterior aspect of xiphoid process converging on central tendon
- are sternocostal hiatus on the lateral sides of slips.
Costal Part:
- wide muscular slips starting from internal surfaces of inferior 6 ribs and costal cartilages.
Lumbar Part:
- arises from lumbar vertebrae via 2 musculotendinous crua (legs)
- the right crua is broader and longer than left.
Median Arcuate Ligament:
- ligament unites crua forming arch over aortic hiatus.
Medial Arcuate Ligament:
- thickening of thoracolumbar fascia forming arches for left and right psoas major muscles.
Lateral Arcuate Ligaments:
- thickening of thoracolumbar fascia forming arches for quadratus lumborum muscles.
Central Tendon:
- peripheral muscular fibers converge on this aponeurotic tendon in center of diaphragm
- three lobes in cloverleaf shape - right lateral is largest, anterior (middle) is intermediate, and left lateral is smallest.
- fibrous layer of pericardium fused with central tendon.
Vena Caval Foramen:
- most superior of the three major openings if diaphragm
- located at the junction of right and middle leaf of central tendon
- contraction of diaphragm on inspiration opens foramen which dilates attached vena cava facilitating blood flow.
Esophageal Hiatus:
- posterior and left of Vena Caval Foramen and has esophagus passing through
- mostly formed in the right crus
- contributes to esophageal sphincter.
Aortic Hiatus:
- does not pierce diaphragm but passes posterior to the median arcuate ligament
- also passing through are the thoracic duct and azygos vein
Greater Splanchnic Nerves:
- pre-ganglionic sympathetic nerves
- pierce the crura going to celiac ganglion.
Anal Triangle:
pudendal canal - fibrous canal splitting obturator internus containing pudendal nerve and vessels (lateral wall of ischioanal fossa)
pudendal nerve - (S2-S4) leaves pelvis between piriformis and coccygeus muscles, hooks around sacrospinous ligament to enter perineum; supplies muscles of perineum
internal pudendal vessels - branch of internal iliac vessels, follow pudendal nerve
Male Pelvis and Peritoneum:
rectovesical fossa - formed by peritoneum reflected from anterior surface of rectum to posterior wall of bladder
paravesical fossa - peritoneal recess on each side of filled bladder (not apparent in empty bladder)
pararectal fossa - peritoneal recess on each side of the rectum
retropubic space - extraperitoneal space between symphysis pubis and bladder; extending dorsally on each side of the bladder (U-shaped)
puboprostatic ligament - thickened superficial fascia of pelvic diaphragm anchoring neck of bladder to pubis; two "cord-like bands" on each side of median plane (equivalent of pubovesical ligaments in females)
retrorectal (presacral) space - between rectum and sacrum and coccyx; limited inferiorly by fascia investing levator ani
pelvic splanchnic nerves - autonomic (parasympathetic) nerves branching off ventral rami S2-S4
internal iliac artery - division of common iliac artery which supplies viscera of pelvic cavity
obturator canal - transverses superior aspect of obturator membrane, containing obturator vessels
obturator artery - branch of internal iliac artery, runs anteroinferiorly on obturator fascia on pelvis lateral wall, leaves pelvis through obturator foramen and supplies muscles of thigh
internal iliac vein - joins with external iliac vein to form the common iliac vein, which unite with partner to form the inferior vena cava at L5 level (tributaries of veins similar to arteries)
ureter - duct carrying urine from kidney to urinary bladder; location in pelvic cavity: crosses external iliac vessels and obturator vessels medially
ductus deferens - begins in tail of epididymis and ends by joining duct of seminal vesical to form ejaculatory duct; ascends in spermatic cord, through inguinal canal, crosses over external iliac vessels to enter pelvis minor, passes along lateral wall, crosses ureter, descends at first superior, than medial to seminal vesicle
Pelvis and Perineum (Orientation):
pelvic brim - circumference dividing greater and lesser pelvis; oblique plane forming angle 55 degrees to horizontal; consists of anterior border of ala of sacrum, arcuate line, pecten pubis, and pubic crest
greater pelvis - false pelvis, superior to pelvic brim, bounded on either side by ilium, part of abdominal cavity
lesser pelvis - true pelvis; inferior to pelvic brim
floor of pelvis - formed by muscles of the pelvic diaphragm, separates pelvic cavity from perineum
pelvis diaphragm - composed of levator ani and coccygeus muscles; supports abdominopelvic viscera
anal triangle - posterior portion of perineum, contains anal canal with ischioanal fossa
urogenital triangle - anterior region of perineum, contains external genitalia and terminal parts of urogenital passages
abdominopelvic cavity - peritoneal cavity; abdomen and lesser pelvis
pelvic fascia
parietal - lines the intrapelvic surfaces of the muscles lining the walls of the pelvic cavity; attached to pelvic brim, continuous with fascia lining pelvic diaphragm
visceral - envelopes pelvic viscera
bony pelvis - skeleton of pelvis, surrounding pelvic cavity; formed anteriorly and laterally by hip bones, posteriorly by sacrum and coccyx
hip bones - consist of ilium, ischium, and pubis
pelvic inlet - superior aperture of the pelvis, surrounded by pelvic brim; extends from sacral promontory to symphysis pubis
promontory of the sacrum - projecting anterior edge of the body of first sacral vertebra
obturator foramen - aperture surrounded by bodies and rami of pubis and ischium (round in males, oval in females)
obturator membrane - fibrous covering of obturator foramen
-Hip bone
-Ischial tuberosity
-Ischial spine
-Sacrospinous ligament
-Sacrotuberous ligament
-Lesser sciatic foramen
-Greater sciatic foramen
-Pubic arch
-Sacrum
-Anterior sacral foramina
-Sacroiliac articulation
-Coccyx
Transverse diameter
Anteroposterior or conjugate diameter
Pelvic outlet pelvis)
Anal Triangle
Gluteus maximus
Ischial spine and tuberosity
Ischioanal (ischiorectal fossa)
Inferior rectal nerve and vessels
Sphincter ani externus
Obturator internus
Tendiuous arch
Levator ani
-pubococcygeus
-iliococcygeus
-coccygeus
Puborectalis mucle
Urogenital hiatus
Urethra
-spongy
-membranous
-prostatic
-sphincter urethrae
Orifice of the ejaculatory duct
Prostatic sinus
Ductus (vas) deferens
-Ampulla
-Seminal vesicle
-Duct of the seminal vesicle
-Ejaculatory duct
Ureter
Urinary bladder
-Muscular coat
-Interior
-trigone
-orifices of the ureters
-internal urethral orifice
Internal iliac artery
-umbilical artery
-superior vesical arteries
-medial umbilical ligament
-obturator artery
-inferior vesical artery
-middle rectal artery
-internal pudendal artery
-inferior gluteal artery
-superior gluteal artery
-iliolumbar and lateral sacral arteries
Rectal venous plexus
Vesical venous plexus
Prostatic venous plexus
Deep dorsal vein of the pelvis- Vein located in the deep fascia of the anterior penis. Collects blood from the cavernous spaces of the penis via the venous plexus, and passes deep to the arcuate pubic ligament and joins the prostatic venous plexus. Blood drains from the erect penis through this vein during detumescence (loss of erection).
Anal canal- Terminal and most inferior part of the large intestine. It begins at the narrowing formed by the U-shaped sling formed by the puborectalis muscle and ends at the anus, about 4 cm in adults.
Anal columns (a.k.a. rectal column)- Longitudinal ridges in the mucous membrane of the upper half of the anal canal containing terminal branches of the superior rectal artery and vein (which branch from the inferior mesenteric artery and vein). One site of anastamosis between portal veins system and the systemic veins system. They are frequently the sites of varicose veins and rupture in cases of portal hypertension.
Anal valves- The inferior ends of anal canals are joined by semilunar folds of epithelium, which are located inferior to the anal sinuses. The inferior edges of the anal valves form the pectinate line.
Sphincter muscles- There are two anal sphincter muscles, internal and external. The internal in involuntary, a thickening of the circular muscular layer of the intestine, and innervated by pelvic splanchnic nerves. The external anal muscle is voluntary, which blends with the puborectalis muscle and is innervated by inferior rectal nerves and the perineal branch of S4 nerve. Both must relax for defecation.
Rectal exam- Palpation of the rectum and nearby structures through the rectal wall with gloved fingers. In both sexes, several bony landmarks can be felt (pelvis sacrum, coccyx, ischial spines and tuberosities), as well as enlarged internal iliac lymph nodes, thickening of the ureters, and swelling in the ischioanal fossae. The cervix can be palpated in females, while the prostate and seminal vesicles are palpable in males.
Piriformis muscle- A muscle located on the posterior wall of pelvis minor, it goes from the anterior sacrum through the greater sciatic foramen to the greater trochanter of the femur. Innervated by ventral rami of S1 and S2, it abducts the flexed thigh and stabilizes the head of the femur in the acetabulum. It is the landmark of the gluteal region. Superior gluteal vessels and nerves emerge above piriformis, while inferior gluteal vessels and nerves emerge inferior to it. The sciatic nerve and pudendal vessels and nerve also emerge inferior to piriformis.
Sacral plexus- Large pelvic plexus anterior to piriformis muscle, formed by the lumbosacral trunk and ventral rami of S1-S4 nerves. The two main nerves of the sacral plexus are the pudendal and sciatic.
Gluteal arteries- The superior gluteal artery is a branch of the posterior division of the internal iliac artery, it leaves the pelvis through the greater sciatic foramen superior to piriformis muscle and serves the gluteal muscles in the buttock. The inferior gluteal artery is a branch of the anterior division of the internal iliac artery, it leaves the pelvis through the inferior part of the greater sciatic foramen, goes inferior to piriformis muscle and serves the muscles and skin of the inferior buttock and posterior thigh.
Pudendal nerve- Arises from ventral rami of S2 to S4 nerves, leaves the pelvis inferior to piriformis muscle, hooks around the sacrospinous ligament and enters the perineum through the lesser sciatic foramen. Supplies the muscle of the perineum, external anal sphincter and ends as the dorsal nerve of the clitoris in females and penis in males. It is the sensory nerve of the external genitalia.
Sympathetic chain and ganglia- The sympathetic chain is a pair of large nerve trunks, which flank each side of the vertebral columns. These nerves serve the functions of the sympathetic part of the autonomic nervous system, including internal organs and visceral structures in the somatic part of the body (such as sweat glands and erector pili muscles in the skin). The sympathetic ganglia are enlargements in the sympathetic chain that accommodates the synapses of the sympathetic nervous system. The communicating rami serve as nerve conduits between the ventral roots of the spinal nerves and sympathetic ganglia.
Female urogenital triangle- Triangle formed by the right and left ischial tuberosities and the pubic symphysis. It contains the external genitalia, urethra and vagina. Urethra Canal that carries urine from the urinary bladder to the outside of the body.
Vagina- A thin walled fibromuscular tube that lies between the bladder and rectum, and extends from the cervix to the outside of the body. It serves as the birth canal, a passage for menstrual flow and receives the penis during sexual intercourse.
Uterus- A hollow, thick walled organ located in the female pelvis anterior to the rectum and posterior and superior to the urinary bladder. It functions to receive, retain and nourish a fertilized egg that enters the uterus through the uterine tubes. It greatly enlarges to accommodate the growing fetus. Its lumen is connected to the vagina through the internal ostium, cervical canal, and external ostium.
Fornix of vagina- The vaginal recess around the cervix.
Mons pubis - rounded fatty elevation located
anterior to the pubic symphysis and lower pubic region. It consists
mainl of a pad ofo fatty connective tissue deep to the skin. The mons
pubis becomes covered with coarse pubic hairs during puberty. Labia
Majora - two symmetrical folds of skin which provide protection for
the urethral and vaginal orifices that open into the vestibule of the
vagina.
Labia Minora - two thin, delicate folds of fat-free hairless skin,
which are located between the labia majora.
Vestibule of the Vigina - space between the labia minora.
Clitoris - homologous with the penis, and is an erectile organ. The
clitoris is located posterior to the anterior labial commissure,
where the labia majora meet. It is hidden by the labia when it is
flaccid. The clitoris consists of a root and a body which are
composed of two crura, two corpora coavernosa, and a glans.
Vaginal Orifice - This large opening is located inferior and posteror
to the much smaller external urethral ofifice. The size and
appearance of the vaginal orifice varies with the condition of the
hymen, a thin fold of mucous membrane that surrounds the vaginal
orifice.
External urethral orifice - This median aperture is located posterior
to the clitoris and immediatley anterior to the vaginal orifice. On
each side fo this orifice are the openings of the ducts of the
paraurethral glands; these glands are homologous to the prostate.
Perineal body - located between the posterior labial commissure and
the anus.
Round ligament of the uterus - emerges from the superficial inguinal
ring ( in females), lies anteroinferiorly of the uterus within the
broad ligament.
Posterior labial nerves and vessels - arterial supply to the vulva is
from two external pudendal arteries and one internal pudendal artery
on each side. The internal pudendal artery supplies the skin, sex
organs, and the perineal muscles. The labial arteries are branches of
the internal pudendal artery, as are the dorsal adn deep arteries of
the clitoris. Lavial veins are tributaries of the internal pudendal
veins. Nerves to the vulva re branches of the ilioinguinal nerve, the
genital branch of the genitofemoral, and the perineal branch fot eh
femoral cutaneous, and the perineal nerve.
Suspensory ligament of the clitoris - homologous to suspensory
ligament of the penis.
Superficial perineal space - Bounded inferiorly by the superficial
perineal fasica dn superiorly by the perineal membrane. The
superficial perineal muscles are the the superficial perineal space
(superficial transverse perineal muscle, bulbospongiousus muscle,
ischiocavernous muscle).
superficial perineal fascia - As in the male, there is a fatty layer
of superficial fasica and a membranous layer of subcutaneous
connective tissue. These layers are continous over the labia majora.
The membranous fascia attaches medially to the pubic symphysis and
laterally to the body of the pubis.
Transverse perinei superficialis - passes in the base of the
sperficial perineal space form the ischial ramus to the perineal
body.
Ischicavernosus - attaches to the ischial ramus but inserts into the
crus of the clitoris.
Bulbospongiosus - arises from the perineal body, passes around the
vagina, and inserts into the clitoris.
Bulbs of the vestibule - Two large elongated masses of erectile
tissue. They lie along the sides of the vaginal orifice, deep to the
bulbospongiosus muslce and are homologous with the bulb of the
penis.
Greater Vestibular Gland - located on each side of the vestiblue of
the vagina, posterolateral to the vaginal orifice. They are round or
oval in shpae and the bulbs of the vestiblue parly overlap them
posteriorly. Theyk are homologous with the bulbourethral glands in
males and secrete lubricating mucous into the vestible of the vagina
during sexual arousal.
-clitoris
-glans
-prepuce
-body
-crura
Deep perineal space
-inferior fascia of the urogenital diaphragm
-deep perineal space or pouch
-urethra and vagina
-transversus perinei profundus
-sphincter urethrae
-superior fascia of the urogenital diaphragm
-pubococcygeus
-branches of the internal pudendal vessels
-branches of the pudendal nerves