For MT2 Lec Flashcards
1
Q
Bony landmarks of abdomen
A
Bony landmarks
a. xiphoid process
b. costal margin
c. anterior superior iliac spine
d. pubic crest
e. pubic tubercle
f. pubic symphysis
2
Q
Regions of the abdomen
A
The most common is a division into quadrants using the median plane and the umbilicus
3
Q
External oblique
A
generally runs inferomedially from ribs 5-12 to the iliac crest and pubic tubercle; aponeurosis forms the anterior-inferior part
4
Q
Superficial inguinal ring
A
A triangular r gap in the aponeurosis supero lateral to the pubic tubercle
5
Q
Inguinal ligament
A
extends from the anterior superior iliac spine to the pubic tubercle. The lowest part of the external oblique aponeurosis is
thickened and folded inward on itself to form the inguinal ligament. The inferior border of the inguinal ligament is continuous with the deep fascia of the thigh—the fascia lata.
6
Q
Línea alba
A
Where fibers from both sides interlace in the median plane
7
Q
Internal oblique
A
generally runs superomedially (perpendicular to external oblique fibers) from
the iliac crest to the linea alba
8
Q
Transversus abdominis
A
a. generally runs in a transverse direction from the costal margin and iliac crest
to the linea alba; forms the deepest muscle layer
b. conjoint tendon—lowest tendinous fibers of the internal oblique join with
transversus abdominis to pass from the lateral part of the inguinal ligament
to the pubic crest; reinforces a weak area of the abdominal wall
9
Q
Rectus abdominis
A
Arises from the symphysis and pubic crest, and inserts into the 5th, 6th, and 7th costal cartilages. Most of the Rectus abdominis muscle is enclosed in the rectus sheath, which is composed of the aponeuroses of the external
oblique, internal oblique, and transversus abdominis muscles.
Protect abdominal muscles
Raise inter abdominal pressure
10
Q
Transversalis fascia
A
fascia on the inner surface of the transversus abdominis; it
passes behind the rectus sheath and crosses the median plane. Internal to the
transversalis fascia is the peritoneum.
11
Q
Functions of the muscles of the abdominal wall
A
a. laterally flex and rotate trunk; rectus abdominis flexes the trunk; assist in
positioning of the trunk to support limb movements
b. increase intra-abdominal pressure and elevate the diaphragm during forced
expiration
c. protect the viscera
d. help maintain posture
e. increase intra-abdominal pressure to help in micturition, defecation,
vomiting, and parturition by contracting simultaneously with the diaphragm
while the airway is closed
12
Q
Innervation for abdominal wall
A
the skin and muscles of the anterior abdominal wall are supplied segmentally
by spinal nerves T7-L1, which includes:
1. Intercostal nerves (T7-T11)
2. Subcostal nerve (T12)
3. Iliohypogastric and ilioinguinal nerves (L1)
13
Q
Superior epigastric artery from
A
Internal thoracic artery
14
Q
Inferior epigastric artery from
A
External iliac artery
anastomoses between the
superior and inferior epigastric arteries provide collateral circulation between the
subclavian and external iliac arteries.
15
Q
Inguinal canal
A
oblique passage 3-5 cm long, through the abdominal wall; it is occupied in males by the
spermatic cord and in females by the round ligament of the uterus, and runs parallel to and just above the medial half of the inguinal ligament. The inguinal canal has been likened to an arcade of three arches formed by three flat abdominal muscles through which the testes and spermatic
cord or the round ligament migrate during development to reach the scrotum or labia majora
16
Q
Superficial inguinal ring
A
—a triangular shaped defect in the aponeurosis of the
external oblique muscle, lateral to the pubic tubercle. This is the exit of the inguinal
canal.
17
Q
Deep inguinal ring
A
oval opening in transversalis fascia. This is the internal
entrance into the inguinal canal. The inferior epigastric artery lies at the medial
boundary of the deep inguinal ring, which is located deep to the midpoint of the
inguinal ligament.
18
Q
Testes develop in
A
lumbar region deep to the transversalis fascia. During the third
trimester, they pass through the inguinal canal. A diverticulum of peritoneum—the
processus vaginalis—evaginates the anterior abdominal wall and travels alongside the
testis. Accompanied by the ductus deferens and the testicular vessels, the testes usually
enter the scrotum before birth and the processus vaginalis obliterates, leaving a bubble of
peritoneum in the scrotum anterior to the testes, the tunica vaginalis.
19
Q
How do the ovaries descend
A
ovaries also descend from the posterior abdominal wall to a point just below the pelvic
brim. The gubernaculum attaches to the uterus, where it divides into the round ligament of
the uterus and the ovarian ligament.
20
Q
Spermatic cord begins
A
at the deep inguinal ring and ends at the posterior border of the testis,
and is composed of several layers of structures and tissues; the most important are:
A. Ductus (vas) deferens
B. Testicular artery
C. Pampiniform plexus of veins—ultimately converge to form the testicular vein
D. Autonomic nerves
E. Cremasteric fascia and muscle—derived from the internal oblique muscle
1. Cremasteric reflex- stroking the inner thigh causes contraction of cremaster muscle,
raising the testicle in the scrotum. Mediated by the genital branch of the
genitofemoral nerve.
21
Q
Scrotum
A
pouch of skin situated below the pubic symphysis. It is divided into two compartments
composed of 2 layers: skin and smooth muscle. The layers of the scrotum are indistinct in
the adult, but are derived from the layers of the anterior abdominal wall.
22
Q
Túnica vaginalis
A
—a peritoneal sac surrounding the testes. It consists of a parietal layer and
a visceral layer (adjacent to the testis and epididymis). A small amount of fluid in the cavity
of the tunica vaginalis separates the visceral and parietal layers and enables the testis to
move freely in the scrotum.
Hydrocele—an abnormal accumulation of fluid in the cavity
of the tunica vaginalis.
23
Q
Innervation of scrotum
A
genital branch of the genitofemoral nerve, ilioinguinal nerve, pudendal nerve,
and posterior femoral cutaneous nerve
24
Q
By the time testicular artery gets to teste it is
A
2 degrees cooler
25
Testes
. Paired oval organs that produce spermatozoa after puberty, and secrete hormones, which
are responsible for the secondary sexual characteristics of the male. The testis is surrounded
by a tough fibrous capsule—the tunica albuginea.
26
Blood supply of testes
B. Blood supply—testicular artery, a branch of the abdominal aorta. A venous network, the
pampiniform plexus, drains the testis; these veins converge to form the testicular vein.
Varicocele—a condition of enlargement (varicosity) of the veins of the spermatic cord,
which often results from defective valves in the testicular vein.
27
Epididymus
applied to the posterior margin of the testis. The epididymis connects the
tubules in the testis to the ductus deferens.
28
Hernias commonly occur in
they occur in the inguinal, femoral, and umbilical regions. Hernias can be congenital, due to a
failure of the processus vaginalis to obliterate, or are acquired, due to weakness of the anterior
abdominal wall. When a weakened condition of the muscles exists, repeated increased intra-
abdominal pressure may induce herniation.
29
Indirect hernia
a. A congenital weakness in the
abdominal wall at the site of
passage of the testis. It is
often the result of a
congenitally persistent
processus vaginalis.
b. Intestinal loop enters the deep
inguinal ring. It can transverse
the canal and emerge at the
superficial ring. It does not
have to pass the entire length
of the inguinal canal to qualify
as an indirect inguinal hernia, although it can.
30
Direct hernia
These protrude medial to the
inferior epigastric artery and move
forward to the superficial ring in the
inguinal triangle; thus, they come
directly through the body wall at the
inguinal triangle, an area of
weakness in the abdominal wall.
This hernia does not pass through
the deep inguinal ring, but emerges
through or around the conjoint
tendon to reach the superficial
inguinal ring. Direct hernias are rare in women
31
Peritoneum
peritoneum is a thin, serous membrane, which lines the walls of the abdominal and pelvic
cavities, and either partially or completely covers viscera contained within it.
Secretes a small amount of fluid that lubricates and facilitates movement of the organs; the
parietal and visceral layers are separated only by this thin layer of peritoneal fluid.
32
Parietal peritoneum
Lines the walls of the abdominal walls of the abdominal and pelvic cavities
33
Visceral peritoneum
Covers the organs directly
34
Peritoneal cavity
potential space between the parietal and visceral layers. The cavity is
completely closed in the male, but in the female, there is a communication with the exterior
of the body through the uterine tubes, the uterus, and the vagina.
35
Ascites
An abnormal accumulation of serous fluid in the peritoneal cavity
36
Greater sac
the main compartment of the peritoneal cavity extending from the
diaphragm to the pelvis. A surgical incision through the anterior abdominal wall
enters the greater peritoneal sac.
37
Lesser sac (o mental bursa)
a pouch situated behind the lesser omentum and
stomach, and in front of structures on the posterior abdominal wall. It allows for
free movement of the stomach. The right margin of the lesser sac opens into the
greater sac through the omental (epiploic) foramen. The sac projects upward to the
diaphragm; however, the downward projection, between the layers of the greater
omentum, fuses shortly after birth.
38
39
Retroperitoneal organs
Organs covered only in front by peritoneum and not suspended by a Mesentery
40
Peritoneal organ
surrounded by visceral peritoneum and suspended by a mesentery from the abdominal
wall. An “intraperitoneal” structure would have to be within the peritoneal cavity, and
normally the peritoneal cavity only has a small amount of fluid in it.
41
Mesentery
a double layer of peritoneum that attaches part of the intestines to the
posterior abdominal wall. When an organ protrudes into the peritoneal sac, it takes
its vessels and nerves with it. They are located between the two layers of peritoneum
forming the mesentery.
42
Omentum
two-layered fold of peritoneum that attaches the stomach to another
viscus
greater omentum—2 layers of mesentery folded back on each other (i.e., a
4-layered structure); attached to the greater curvature of the stomach and the
inferior border of the transverse colon
lesser omentum—from the lesser curvature of the stomach and the first part
of the duodenum to the liver; consists of the hepatogastric and
hepatoduodenal ligaments
43
Parietal peritoneum is supplied by
Same somatic nerves that innervate the
overlying muscle and skin. The diaphragmatic peritoneum is innervated by the phrenic
nerve; peritoneum in the pelvis is innervated by the obturator nerve. Parietal peritoneum
is sensitive to pain, temperature, touch, and pressure. Inflammation of parietal
peritoneum results in well localized pain that is often referred to areas of skin supplied
by the same nerves.
44
Visceral peritoneum is
sensitive to stretch and is innervated by autonomic nerve fibers.
Overdistension of viscera will lead to a sensation of pain that is poorly localized.
45
Peritoneal fluid
—secreted by the peritoneum; ensures that mobile viscera can move
upon one another
46
Functions of peritoneum
Peritoneal fluid—secreted by the peritoneum; ensures that mobile viscera can move
upon one another
2. The greater omentum and peritoneal coverings tend to fuse in the presence of
infections. Thus, intraperitoneal infectors remain localized.
3. Large amounts of fat are stored in the peritoneal ligaments and mesenteries, and
especially large amounts in the greater omentum.
47
Abdominal part of esophagus enters
abdomen through an opening in the
diaphragm at the level of T10 vertebra, and enters the stomach at its cardiac orifice.
Remember that the thoracic part of the esophagus is in the superior mediastinum.
48
Gastroesophageal junction
constitutes a barrier (physiologic sphincter) to the
reflux of contents from the stomach to the esophagus. This lower esophageal
sphincter has three components:
a. esophageal muscle
b. diaphragmatic sling
c. angle of entrance of the esophagus into the stomach
Heartburn—a painful stimulation of the lower esophagus that occurs when acidic
gastric contents reflux past the sphincter.
49
Innervation of esophagus
2. Innervation—supplied by the vagus nerves and the thoracic sympathetic trunks via
the greater splanchnic nerve.
50
Parts of stomach
a. Cardiac part—between abdominal end of
esophagus and stomach
b. Fundus—above entrance of the esophagus
c. Body—between the fundus and pylorus
d. Pyloric part—opens into duodenum
e. Pyloric sphincter—controls the rate of
discharge of stomach contents into the
duodenum
f. Lesser and greater curvatures
Left upper quadrant
51
Which part of stomach is most fixed
Cardiac orifice
52
How does the fundus move with the diaphragm
Fits into curve of the left dome of the diaphragm and moves with it
53
Is the stomach fixed
fixed at both ends
but in between is very mobile. The entire anterior surface is covered by
peritoneum. The posterior surface is covered by peritoneum except where the
hepatogastric ligament is attached. Anterior to the stomach is the anterior
abdominal wall. Posterior to the stomach is the lesser sac and the pancreas. The
shape and position of the stomach vary in different persons, and in the same
individual as a result of movements of the diaphragm during respiration.
54
Functions of stomach
1) storage of food, (2) mixing stored
food with gastric secretions, and (3) controlling the rate of delivery into the
duodenum. The stomach stores ingested food and prepares it for eventual
treatment by the small intestine.
55
What does the stomach synthesize
The stomach synthesizes:
a. HCl (stomach pH is almost as acidic as pure sulfuric acid)
b. Pepsinogen (converted to pepsin by HCl)
c. Intrinsic factor (aids vitamin B12 absorption)
d. Mucus
e. Gastrin (increases acid secretion, pepsinogen secretion, and overall motility)
56
Digestión occurs
digestion occurs mechanically and enzymatically. Waves of contraction
(peristalsis) create an agitator action similar to that in a washing machine. Very
little absorption of foodstuffs goes on at the stomach level except readily
dissolvable, relatively short-chain compounds
57
Blood supply for stomach
All arteries are derived directly or indirectly from the
celiac trunk.
58
Left gastric a
Supplies esophagus and upper part of stomach
59
Splenic a
Give off pancreatic branches, left gastroomental (gastroepiploic), and short gastric arteries
60
Common hepatic a
branches into proper hepatic
artery and gastroduodenal artery. The proper hepatic artery
gives off the right gastric artery, then branches into right and
left hepatic arteries.
61
Venous drainage for stomach
directly or indirectly into the
portal vein: 1) right and left gastric, along the lesser curvature
2) right and left gastroomental (gastroepiploic) and short
gastric, along the greater curvature.
62
Nerve supply
derived from the celiac sympathetic plexus through the plexuses
around the gastric and gastroomental (gastroepiploic) arteries. The parasympathetic
nerve supply is derived from the vagus nerve.
63
Gastric ulcer
This is due to an imbalance between acid secretion and
mucosal defenses, as well as infection with a bacterium known as H. pylori.
It can result in epigastric pain and GI bleeding. It can also perforate, leading
to peritonitis.
64
Hiatal hernia
A portion of the stomach herniates through the esophageal
hiatus into the thorax
65
Pyloric stenosis
An overdevelopment of the pyloric sphincter muscle leads
to gastric outlet obstruction.
66
Parts of duodenum
1. From the pylorus to duodenojejunal junction (flexure), the duodenum is about 10 inches
long and consists of 4 parts. The 1st part (upper duodenal cap) is free and suspended
by the hepatoduodenal part of the lesser omentum. The other parts are fixed
(retroperitoneal).
2. Descending (2nd) part—receives bile duct and pancreatic duct. These come together at
the hepatopancreatic ampulla, which opens at the major duodenal papilla.
3. Inferior (horizontal, 3rd) part—crosses anterior to the aorta and the IVC.
4. Ascending (4th) part—connects with jejunum at the duodenojejunal junction.
67
68
Which parts of duodenum are retroperitoneal
2, 3,4
69
Major (greater) duodenal papilla
—opening for the pancreatic and bile ducts. The opening
of this papilla is guarded by the sphincter of the hepatopancreatic ampulla
70
Functions of duodenum
: The duodenum regulates its environment with hormones that are released from
the duodenal epithelium. Secretin is released when the pH of the duodenum gets too low.
This hormone acts to neutralize the pH of the duodenum by stimulating water and
bicarbonate secretion into the duodenum. This aids in the digestion process as pancreatic
amylase and lipase require a higher pH to function optimally. Another hormone that is
released by the duodenal epithelium is cholecystokinin which is released in the presence of fatty acids and stimulates contraction of the gallbladder while simultaneously causing
relaxation of the sphincter of Oddi to allow delivery of bile into the duodenum to aid in
digestion and absorption of fats.
71
Pancreaticoduodenal arteries
celiac trunk and superior mesenteric artery
72
Venous drainage generally
Follows the arteries into the PORTAL venous system
73
Nerves of the duodenum are from
Sympathetic and parasympathetic nerves of the cefálica and superior mesenteric plexus
74
Duodenal ulcers
when the stomach empties its contents, acid chyme is squirted against
the anterolateral wall of the first part of the duodenum. This becomes an important factor
in producing an ulcer at this site. Duodenal ulcers are more common than gastric ulcers.
75
Small intestine - jejunum and ileum
About 20 feet long, the proximal 2/5 is jejunum and the distal 3/5 is ileum. Where most
digestion and almost all absorption of ingested nutrients occurs.
Attached by the mesentery to the posterior abdominal wall, which permits entrance and
exit of branches of the superior mesenteric artery, vein, and nerves
76
Blood supply of jejunum and ileum
Blood supply—branches (jejunal and ileal) of the superior mesenteric artery. The superior
mesenteric vein drains the jejunum and ileum
77
Lymphatics of ileum and jejunum
Lymphatics—vessels within the intestinal wall empty into plexuses within the intestinal
wall, then into larger vessels. Lymph drains into the mesenteric group of lymph nodes,
and ultimately into the thoracic duct. This is the route taken by digested fat. Other nutrients
pass into the portal vein.
78
Nerves of jejunum and ileum are derived from
The nerves of the jejunum and ileum are derived from the vagus and greater splanchnic
nerves through the celiac ganglion and the nerve plexus around the superior mesenteric
artery.
79
Common cause of intestinal bleeding
In about 2% of the population, a diverticulum in the ileum (Meckel's diverticulum) is
present as an outpouching of the intestinal wall—a persistence of the omphalomesenteric
duct of the embryo. This is a common cause of intestinal bleeding.
80
Primary function of large intestine
Absorption of water and electrolytes and the storage of digested material until it can be excreted as feces
81
Distinguish large from small intestine
1) teniae coli, three thickened bands of longitudinal muscle; 2)
haustra, sacculations of its wall; and 3) epiploic appendages, pouches of peritoneum filled with
fat. The contractions of the teniae coli shorten the walls of the large intestine (peristalsis),
propelling the fecal matter within and forming the visible sacculations known as haustra. The
epiploic appendages serve a protective and defensive mechanism similar to that offered by
the greater omentum.
82
Cecum
Cecum—the part that lies below the level of the junction of the ileum with the large
intestine. It has a considerable amount of mobility, even though it does not have a
mesentery
83
Vermiform appendix
.
1. Vermiform appendix—a narrow blind tube that joins the cecum about one inch below
the ileocecal opening. It has a short mesentery of its own, the mesoappendix, and has
a considerable range of movement. However, the base of the appendix is fairly
constant at McBurney's Point (sharpest pain found here) —1/3 of the distance from the right anterior superior
iliac spine to the
umbilicus.
84
Ileocecal valve
2. Ileocecal valve—at
the end of the ileum at
the junction of the
cecum with the colon.
The ileocecal valve is
only partly functional
85
Ascending colon
Ascending colon—extends
upward from the cecum to
the right colic flexure.
Peritoneum covers the front
and sides (i.e., it is
retroperitoneal
86
Transverse colon
Transverse colon—begins
at the right colic (hepatic)
flexure, is suspended by the
transverse mesocolon, and
extends to the left colic
flexure.
Phrenicocolic
ligament—attaches left colic flexure to the diaphragm. The transverse mesocolon is
attached to its superior border.
87
Descending colon
Descending colon—passes inferiorly from the left colic (splenic) flexure to the brim of the
pelvis where it becomes continuous with the sigmoid colon at the level of the inguinal
ligament. Like the ascending colon it is retroperitoneal—covered with parietal peritoneum
where it is not in direct contact with the posterior abdominal wall.
88
Sigmoid colon
extends from the iliac fossa to the 3rd sacral vertebra. It lies within the
pelvis, suspended from its wall by the sigmoid mesocolon, and has considerable freedom
of movement.
89
Blood supply of large intestine
1. Ileocolic and right colic branches of the superior mesenteric artery to the ascending
colon and cecum.
2. Middle colic branch of the superior mesenteric artery to the transverse colon.
3. Left colic branch of the inferior mesenteric artery to the descending colon.
4. Sigmoid branch of the inferior mesenteric artery to the sigmoid colon.
5. Superior rectal artery—the terminal branch of the inferior mesenteric artery—to the
rectum.
6. Marginal artery—anastomosis of the colic arteries around the margin of the large
intestine.
90
Appendicitis
—inflammation of the appendix. This is usually caused by obstruction
of the appendix, most often by fecal material. Can result in pain and/or tenderness at
McBurney’s Point- 1/3 of the distance from the right anterior superior iliac spine
and the umbilicus
91
Ulcerative colitis
chronic disease of the colon characterized by severe inflammation and ulceration of the colon and rectum.
92
Diaphragmatic surface of the liver
located just below the dome of the diaphragm and is covered by
peritoneum except at the bare area, where the liver is in direct contact with the
diaphragm.
93
Visceral surface of liver
Visceral—faces posteriorly, caudally, and to the left. It is covered by peritoneum
except at gall bladder and porta hepatis
94
Lobes of liver
4 lobes ; functionally only 2 tho
fissures of the
ligamentum venosum and ligamentum teres hepatis divide the liver into a smaller left lobe
and a larger right lobe. The porta hepatis (portal fissure), fossae for the gall bladder and
groove for the inferior vena cava further divide the right lobe of the liver into a caudate
lobe and quadrate lobe.
functionally, the liver has
only two lobes roughly equal in size; these right and left parts of the liver are functionally
independent and defined by the distribution of the right and left branches of the hepatic
artery, hepatic portal vein and common hepatic duct.
95
Lesser omentum
—attaches the liver to the stomach (hepatogastric ligament) and
duodenum (hepatoduodenal ligament). The free margin of the lesser omentum
contains the portal triad (hepatic artery, bile duct, and portal vein). These structures
pass into the liver in a region called the porta hepatis
96
Falciform ligament
falciform ligament—attaches the liver to the diaphragm and anterior abdominal wall
97
Ligamentum Teres (hepatis)
remnant of the umbilical vein; located in the inferior free
margin of the falciform ligament. Oxygenated and nutrient-rich blood is brought from
the placenta to the fetal liver via the umbilical vein.
98
Ligamentum venosum
5. ligamentum venosum—remnant of the ductus venosus. The ductus venosus shunts
blood from the umbilical vein to the IVC, bypassing the fetal liver
99
Position of liver
the liver lies mostly under cover of the thoracic cage just below the
dome of the diaphragm on the right, and extends a variable distance to the left past the
median plane.
Normally not palpable below the right costal margin
100
Function of the liver
1. Synthesis of proteins and clotting factors; storage of iron, copper, vitamins, and
glycogen; secretion of bile.
2. Important blood forming organ in the fetus.
3. Chemical modification of macromolecules, toxins, and drugs. Everything absorbed
from the GI tract except lipids is first received by the live
101
Proper hepatic artery
a branch of the common hepatic artery (from the celiac trunk)
that brings oxygenated blood to the liver. Near the porta hepatis, the proper hepatic
artery divides into right and left hepatic arteries. These supply 30% of the blood flow
to the liver.
102
(Hepatic) portal vein
2. (Hepatic) Portal vein—collects blood from the capillary beds of the entire GI tract
and brings venous blood, rich in products of digestion, to the liver. This supplies 70%
of the blood flow to the liver.
Carries deoxygenated blood rich in nutrients
103
Portal system
a. Portal system—valves are insignificant or absent. The system begins as a capillary
plexus in the organs of the GI tract, gall bladder, pancreas, and spleen, and ends
by emptying its blood into sinusoids within the liver. The portal vein receives
blood from the superior and inferior mesenteric veins, and the splenic vein.
104
Portal-systemic (portacaval) anastomoses
i. superior rectal vein Û middle and inferior rectal veins to internal iliac veins
ii. left gastric vein Û esophageal veins to azygos vein
iii. paraumbilical veins Û epigastric veins to external iliac veins
105
Hepatic veins
Leave the posterior surface of the liver to open directly into the inferior vena cava (IVC), just below the diagram
106
Portal hypertension
obstruction of normal blood flow through the hepatic circulation, often resulting from cirrhosis. When this occurs, venous blood from the GI tract bypasses the hepatic circulation by flowing through sites of venous
anastomoses between the portal vein and the inferior or superior vena cava. These are
known as portacaval anastomoses and are possible because these vessels lack valves.
Three major sites of anastomoses develop: esophageal, umbilical, and rectal venous
plexuses.
107
Cirrhosis
due to atrophy or destruction of the liver cells and hypertrophy of the
connective tissue. This tissue surrounds the intrahepatic blood vessels and biliary
ducts, impeding circulation of blood flow through the liver.
108
Is liver common site for cancers
Because of its great vascularity, the liver is a common site for metastasis from cancers
in many other body sites.
109
Jaundice
Jaundice—is a yellow appearance of the skin due to an accumulation of bile pigment
frequently as a result of obstruction of the intrahepatic or extrahepatic bile duct
system.
110
Gall bladder
Gall Bladder—lies along the right edge of
the quadrate lobe of the liver in a depression,
the gallbladder fossa.
1. Parts: fundus, body, and neck
2. On the visceral surface of the liver;
covered by peritoneum caudally.
B. Surface Anatomy—gallbladder is located at
the intersection of the linea semilunaris
(lateral margin of rectus abdominis muscle)
and the right costal margin.
111
Liver and developing duodenum relation
liver develops as a bud from the
developing duodenum, and in the adult,
it retains this connection via the bile duct.
112
Hepatic ducts
Bile secreted from liver via hepatic ducts
From R + L lobes of liver
Fuse to form common hepatic ducts
113
What forms bile duct
Cystic duct from gall bladder merges with T he common hepatic duct
114
Bile duct runs
In free edge of the hepatoduodenal ligament to terminate in duodenum
Just before the bile duct enters the second part
of the duodenum, it is joined by the main
pancreatic duct to form the
hepatopancreatic ampulla. The walls
are thickened by smooth muscle forming
the sphincter of the ampulla (the
hepatopancreatic sphincter). The
ampulla opens into the duodenum at the
apex of the greater duodenal papilla.
115
Function of gall bladder
gall bladder stores bile. The bile is produced in the liver and flows into the
duodenum. When the sphincter muscle at the duodenal papilla is constricted, bile is
forced back into the cystic duct and gall bladder. There, the bile is stored, concentrated,
and acidified. At mealtime, the sphincter relaxes, the gall bladder contracts in response
to gastrointestinal hormones and the vagus nerves, and bile is directed to the duodenum.
Bile, being amphiphilic, renders the ingested fats more soluble in water where the
digestive enzymes can function.
116
Blood supply and innervation of gall bladder
Blood Supply—cystic artery (usually a branch from the right hepatic artery). Cystic vein
drains directly into the portal vein.
Innervation—Nerves pass along the cystic artery from the celiac plexus (sympathetic), the
vagus nerve (parasympathetic), and the right phrenic nerve (sensory)
117
Issues w gall bladder
Obstruction of the biliary ducts with a gallstone results in pain,
as well as backup of bile in the ducts. Inflamed gall bladder (cholecystitis) is another
common occurrence. This also causes pain. If the bile cannot leave the gallbladder, it will
enter the blood and cause jaundice.
118
Páncreas
An exocrine and endocrine (islets of Langerhans) gland consisting of a head, body, neck,
and tail. [cancer is really bad]
B. The pancreas is a retroperitoneal structure that lies just deep to the stomach. The head lies
in the “C” of the duodenum and the tail touches the spleen. The pancreas has an extensive
pancreatic duct which enters the major duodenal papilla in company with the bile duct at the hepatopancreatic ampulla. The exocrine glands secrete an alkaline mixture of enzymes
that aid in the digestion of proteins, fats, and carbohydrates. Pancreatic secretion is
regulated by hormones and the vagus nerves.
119
Blood supply and innervation of pancreas
C. Blood supply—branches from the splenic artery, gastroduodenal artery (superior
pancreaticoduodenal artery) and superior mesenteric artery (inferior pancreaticoduodenal
artery). Pancreatic veins drain into the portal, splenic, and superior mesenteric veins.
D. Innervation—sympathetic and parasympathetic fibers reach the gland by passing along
arteries from the celiac and superior mesenteric plexuses.
120
Pancreatitis
Pancreatitis—a serious inflammatory condition of the exocrine pancreas. This may
be caused by a blocked duct or reflux of bile from the hepatopancreatic ampulla into
the pancreatic duct.
121
Cancer of the pancreas
Usually involves its head and accounts for most cases of
extrahepatic obstruction of the biliary system. Because of its deep retroperitoneal
locations, pancreatic cancer is difficult to diagnose early.
122
Cystic fibrosis
Cystic Fibrosis—a genetic disease causing secretion of abnormally thick mucus in the
lungs and pancreas. This leads to serious lung infections, and the inability to digest
nutrients.
123
Spleen
Organ of the lymphatic system consisting of organized masses of lymphatic
tissue intimately associated with blood vessels. In effect, the spleen filters blood. The
spleen is also the site for lymphocyte and monocyte production and is very active in immune
response to antigens. Its macrophages remove debris from the blood and specifically break
down aged red blood cells. The heme portion of the hemoglobin molecule is converted
indirectly into bilirubin, which is conducted to the liver by way of the hepatic portal vein
and incorporated into bile. Accumulation of bilirubin in the blood results in jaundice and
is generally indicative of liver or gall bladder disease. The storage function of red blood
cells in the spleen is minimal
124
Anatomical position of spleen
l.
B. Anatomical position—the spleen is located on the left, at the level of ribs 9-11 in the
abdomen. Two ligaments connect to it: the gastrosplenic (gastrolienal) ligament connects
the spleen to the stomach, and the splenorenal (lienorenal) ligament attaches the spleen to
the posterior abdominal wall in the region of the left kidney. It has a diaphragmatic and
visceral surface. The spleen varies in size and shape and usually fits into a cupped hand.
Parallel to ribs 9,10, 11 behind midaxillary line
125
Blood supply of spleen
Blood supply—splenic artery (from the celiac trunk) and splenic vein, which joins the
superior mesenteric vein to form the portal vein.
126
Splenomegaly
2. Splenomegaly—enlargement of the spleen, which is abnormal and associated with
many diseases, such as mononucleosis, malaria, hemolytic anemia and blood cancers
like leukemia. The notched border is helpful when palpating an enlarged spleen
because when the patient takes a deep breath these notches can often be palpated as it
moves inferoanteriorly, below the left costal margin
127
Injury to spleen
spleen is the most frequently injured organ in the abdomen. Rupture of the spleen
can cause severe intraperitoneal hemorrhage and shock.
128
Abdominal aorta
—begins at the T12 vertebra and ends at the L4 vertebra by dividing into
the right and left common iliac arteries
1. Parietal branches
a. lumbar—small segmental branches
b. common iliac
2. Visceral branches
a. suprarenal
b. renal
c. gonadal (testicular or ovarian)
D. Celiac trunk
E. Superior mesenteric artery
F. Inferior mesenteric artery
129
Celiac trunk
d. celiac trunk
i. left gastric artery—supplies the lesser curvature of the stomach and the
abdominal part of the esophagus.
ii. splenic artery—supplies the spleen, body and tail of the pancreas, and
greater curvature of the stomach via the left gastroomental (gastroepiploic)
branches.
iii. common hepatic artery—supplies the liver via the proper, right and left
hepatic arteries, lesser curvature of the stomach via the right gastric artery,
duodenum via the gastroduodenal artery, head of the pancreas via the
superior pancreaticoduodenal branches, the gall bladder via the cystic
artery, and the greater curvature of the stomach via the right gastroomental
(gastroepiploic) branches
130
131
Superior mesenteric artery
supplies blood to the head of the pancreas (via
inferior pancreaticoduodenal branches), the distal half of the duodenum, the
small intestine, the ascending colon, and the right half of the transverse colon.
The 6-12 branches from the superior mesenteric artery to the small intestine are
collectively called the intestinal arteries. The large artery from the superior
mesenteric to the cecum is called the ileocolic artery. The right colic and middle
colic arteries supply the ascending and hepatic flexure portions of the colon,
respectively.
132
Inferior mesenteric artery
—supplies blood to the left half of the transverse
colon, the descending colon, the sigmoid colon, and the rectum. The left colic,
sigmoid, and superior rectal arteries are all branches of the inferior mesenteric
artery and anastomose by way of the marginal artery near the colon. This artery
provides an anastomotic channel for branches of the inferior and superior
mesenteric arteries
133
Internal iliac arteries
Internal iliac arteries
1. Principal blood supply to the pelvic viscera, perineum, medial thigh, and gluteal
region
134
External iliac arteries
External iliac arteries
1. Become the femoral arteries after passing deep to the inguinal ligament
2. Principal blood supply to the lower limb
135
Posterior abdominal wall
Consists of the diaphragm, vertebral column, posterior wall muscles, and lumbar plexus.
136
Thoracic (respiratory) diaphragm
. Large muscle separating the abdominal and thoracic cavities. Consists of peripheral
skeletal muscle attached anteriorly to the sternum and the costal arches, and a central
fibrous region—the central tendon.
2. Posteriorly, there are two muscular arches—the crura—that extend along the lateral
sides of the lumbar vertebrae and form the aortic hiatus at T12, through which pass
the aorta, thoracic duct, and azygos vein.
3. The esophagus passes through the esophageal hiatus at T10, accompanied by the
vagus nerves.
4. The IVC passes through the central tendon at T8, along with the phrenic nerve.
137
Innervation of diaphragm
Phrenic nerve (C3-C5)
138
Clinical conditions
a. Diaphragmatic hernia
b. Hiatal hernia
139
Psoas major
—arises from the transverse processes and vertebral bodies of T12 to
L5 and inserts onto the lesser trochanter of the femur along with the iliacus muscle;
innervated by the lumbar plexus (ventral rami of L1, L2 and usually L3 spinal nerves)
140
Quadratus lumborum
—arises from the iliac crest, and inserts onto the 12th rib and
transverse processes of the upper four lumbar vertebrae; innervated by the T12-L4
spinal nerves; extends and laterally flexes the vertebral column and fixes the 12th rib
during inspiration.
141
Iliacus
—arises from the iliac fossa and attaches to the lesser trochanter of the femur
along with the psoas major muscle; innervated by the femoral nerve.
* Together, the psoas major and iliacus muscles form the iliopsoas muscle, the chief
flexor of the thigh.
142
Lumbar plexus
A network of nerves formed within the psoas major muscle by ventral rami of spinal nerves
L1 to L4. These provide innervation to the abdominal wall and parts of the pelvis and
perineum.
The course of these nerves is somewhat controversial. Thus, for the first four nerves listed,
you only need to know the basic information presented below. However, the femoral and
obturator nerves are important nerves of the lower limb and you will be responsible for
learning the details of those.
143
Iliohypogastric nerve (L1)
motor to the internal obliques and transversus
abdominis muscles; sensory to the pubic region.
144
Ilioinguinal nerve (L1)
2. Ilioinguinal nerve (L1)—motor to the abdominal wall; sensory to the scrotum/labia
and the base of penis/clitoris; terminal branch passes through the superficial inguinal
ring.
145
Genitofemoral nerve
3. Genitofemoral nerve (L1-2)—formed within the psoas major muscle; genital branch
to the cremaster muscle, femoral branch is sensory to the medial thigh.
146
Lateral femoral cutaneous
4. Lateral femoral cutaneous nerve (L2-3)—runs along the lateral aspect of the iliacus
muscle; passes beneath the inguinal ligament to supply sensation to lateral thigh.
147
Femoral nerve (L2-4)
5. Femoral nerve (L2-4)—major nerve to the muscles of the anterior thigh; passes
beneath the inguinal ligament just lateral to the psoas major muscle
148
Obturator nerve (L2-4)
Obturator nerve (L2-4)—major nerve to the adductor muscles in the medial thigh;
passes medial to the psoas major muscle; leaves the pelvis via the obturator foramen
149
Kidney
Retroperitoneal. Each kidney lies in a
mass of perirenal fat posterior to the
peritoneum at the L1 to L4 vertebral
level; the right kidney may be lower than
the left.
150
Hilum of kidney
2. The hilum of the kidney is located on its
concave medial surface where the renal
artery and vein, and the ureter enter the
substance of the kidney. As the ureter
approaches the hilum, it is dilated to
form the renal pelvis. In the depths of
the hilum, the pelvis divides into several
major calyces (singular, calyx), which in
turn divide into 7-14 minor calyces that
receive urine from the largest collecting
ducts. The ureter and calyces comprise a
conducting system that carries urine from
the kidney to the bladder. The renal pelvis
and its branching calyces fit within a space
called the renal sinus, along with the renal
vessels.
151
Kidney function
a. Maintain ionic balance of blood and excrete waste products as urine. Some crystalline compounds may form in the calyx and form kidney stones.
b. Regulation of blood pressure
c. Renal transplantation is an established operation for the treatment of selected
cases of chronic renal failure. The transplant site for the kidney is the lower
abdomen.
152
Uréter
1. Retroperitoneal throughout its course. The ureter descends from the renal pelvis to
the bladder, anterior to the psoas major muscle, crossing anterior to the external iliac
vessels to enter the lateral aspect of the pelvis, and proceeds to the posterosuperior
aspect of the urinary bladder. Here it passes obliquely through the bladder wall,
forming a functional valve to prevent the reflux of urine.
2. Blood supply from renal artery superiorly, gonadal artery during descent, and superior
vesical artery near the bladder.
153
Innervation ureter
Autonomic nerves from the renal plexus
154
Renal stones
flank pain radiating to the groin frequently results from a stone
passing from the kidney to obstruct in the ureter. Often results in blood in the
urine.
155
Obstruction
usually occurs at three areas, and can result in hydronephrosis
i. junction of ureter and pelvis (UPJ)
ii. where it crosses pelvic inlet
iii. its intramural portion (in the wall of the bladder)
156
Suprarenal (adrenal) gland
1. Relations—at the superior pole of the kidney, within the renal fascia
2. Structure and function
D. a. Capsule—surrounding each gland
b. Cortex—secretes mineralocorticoids, glucocorticoids, and sex hormones:
cortisol, aldosterone, progesterone, estradiol and androgens.
c. Medulla—secretes epinephrine and norepinephrine
157
Blood supply of adrenal gland
Suprarenal arteries from the aorta
158
Innervation of the adrenal gland
The nerves are mainly preganglionic sympathetic fibers that are derived
from splanchnic nerves. The majority end in the medulla and help regulate
epinephrine secretion. The cortex receives only a vasomotor supply. Medullary cells
are homologous with sympathetic ganglion cells
159
False pelvis
Structure w in are Really part of the abdomen
160
True pelvis
Contains pelvic viscera (bladder, rectum, uterus etc)
161
Perineum
contains the anal canal (in
the so called anal triangle) and the external genitalia (in the urogenital triangle). The
term perineal should not be confused with peritoneal, nor with peroneal—an old
adjective describing the lateral aspect of the leg!
162
Bony pelvis
important
for the transfer of body weight
from the axial skeleton to the
lower limbs, attachment of
postural and locomotor
muscles, and protection of
pelvic viscera. It is composed
of the two wing-shaped hip
bones laterally and anteriorly,
and the sacrum and coccyx
posteriorly.
163
Hips bones formed by fusion of which bones
the ilium, ischium and pubis.
The ilium, ischium,
and pubis meet near the center
of the acetabulum, the socket of the hip joint. Important landmarks on the ilium include
the iliac crest and the iliac fossa. The ilium articulates with the sacrum at the broad
sacroiliac joints. The inferiorly located ischium forms (together with muscles) most of
the lateral walls of the true pelvis; the anteriorly located pubis is formed from two rami
and is part of the anterior wall of the true pelvis. The left pubis and right pubis meet
one another at the pubic symphysis.
164
Opening into true pelvis
Called the pelvic inlet or the superior pelvic aperture.
It is formed by the: sacral promontory, arcuate lines of the ilia, pectineal lines of the
pubic bones, and upper border of the pubic symphysis
165
Inferior pelvic aperture
s. The inferior pelvic aperture
(pelvic outlet) is the opening defined posteriorly by the coccyx, laterally by the ischial
tuberosities and sacrotuberous ligaments, and anteriorly by the inferior part of the pubic
symphysis. The size and shape of the pelvic inlet and outlet are often related to
complications in childbirth.
166
Sacroiliac ligaments
Considered strongest ligaments in body
Help bind hip bones to the sacrum at the sacroiliac joint
167
Sacrospinous ligament
sacrospinous ligament travels from the sacrum
to the spine of the ischium and closes the greater sciatic notch, forming the greater
sciatic foramen
168
Sacrotuberous ligament
sacrotuberous ligament joins the sacrum with the ischial
tuberosity, forming the lesser sciatic foramen. Relaxin, a hormone produced by the
corpus luteum during pregnancy, relaxes pelvic ligaments and increases joint
movements. This can increase the transverse diameter of the pelvis by up to 15%.
169
Additional foramina of pelvis
Additional foramina in the bony pelvis include the obturator foramen (found between
the ischium and the pubis) and the sacral foramina. The obturator membrane covers
most of the obturator foramen. The obturator canal, a small gap in the obturator
membrane, is the route followed by nerves and vessels into the medial part of the thigh.
The major route followed by vessels and nerves into the anterior thigh is deep to the
inguinal ligament.
170
Levantar ani muscles arise
arise from or near the pubis and the tendinous arch of
the obturator internus muscle, and insert on their counterpart, pelvic viscera, or the
coccyx at the midline. The 3 parts of the levator ani muscle are: 1) the puborectalis, 2)
the pubococcygeus, and 3) the iliococcygeus. The names of the muscles describe their
origins and insertions.
171
Coccygeus
coccygeus muscle arises from
the ischial spine and sacrospinous
ligament, and inserts on the coccyx.
It forms the posterior part of the
pelvic diaphragm.
172
Functions of levator ani mm and coccygeus
levator ani and coccygeus
muscles support the pelvic viscera in
both males and females, and the fetal
head in pregnant women. They can
assist the abdominal muscles in
increasing abdominal pressure; they
also help support and anchor the prostate and vagina. The muscles of the pelvic
diaphragm can be injured during childbirth. This may result in poor support of the
bladder, leading to urinary incontinence, and poor support of the uterus, allowing it to
prolapse through the vagina. In addition, the puborectalis muscles form the puborectal
sling, part of the external anal sphincter. When relaxed, the puborectal sling allows the
rectum to straighten, thus facilitating defecation.
173
Sacral plexus
network of nerves found on (and in) the anterior surface of the piriformis muscle. It is composed of the lumbosacral trunk (L4 and L5) and the ventral rami of S1, S2, S3 and S4. Most of the branches of the sacral plexus leave the true pelvis via the greater sciatic foramen. The major branches of the sacral plexus are the sciatic nerve (L4-S3), the pudendal nerve (S2-S4), and the superior and inferior gluteal nerves (more later). The pudendal nerve exits the pelvis via the greater sciatic foramen, but returns to the perineum via the lesser sciatic foramen after looping around the sacrospinous ligament.
174
Path of pudendal n
After its formation, the pudendal nerve leaves the pelvis through the lower part of the greater sciatic foramen. It then crosses the sacrospinous ligament and then re-enters the pelvis through the lesser sciatic foramen.
After re-entering the pelvis, it accompanies the internal pudendal artery and vein, coursing through
the pudendal canal (a structure formed by the fascia of the obturator internus muscle). Inside the pudendal canal, the nerve divides into branches, first giving off the inferior rectal nerve providing motor innervation to the external anal sphincter and sensation below the pectinate line, then the perineal nerve, before continuing as the dorsal nerve of the penis or clitoris.
175
Ureters
Enter true pelvis near where the common iliac arteries become external and internal iliac arteries
In women, pass inferior to broad ligament and enter near fornix of vagina
Men, run deep to peritoneum and crossed by ductus deferens
176
What prevents backflow of urine
When the bladder fills,
the ureters are pinched shut by the expanding walls of the bladder. This prevents the
reflux of urine into the ureters when the bladder is distended
177
Urinary bladder
+ trigone
apex, base,
superior surface, and two inferolateral surfaces.
inner surface of the
empty bladder is
corrugated except at the
trigone—the triangular
patch that lines the base.
The ureters enter the
bladder near the superior
angles of the trigone, the urethra forms near the inferior angle of the trigone. The trigone
is very sensitive to stretch and signals when the bladder is distended
178
Wall of bladder
. The wall of the
bladder is composed of layers of smooth muscle. Near the neck of the bladder (where
the urethra begins), these muscles form the involuntary internal sphincter of the bladder.
Parasympathetic nerve fibers are motor to the smooth muscle of the bladder, and are inhibitory to the involuntary sphincter. When stimulated (e.g., by distension of the
bladder), they will force the bladder to contract and expel urine into the urethra. This
reflex can be controlled by higher brain centers (a.k.a., potty training).
179
Urethra
short muscular tube that runs near the anterior surface of
the vagina. It passes through the pelvic diaphragm and ends at the external urethral
orifice in the vestibule of the vagina (the space between the labia minora). The internal
urethral sphincter in females is functional, not anatomic. It is made of smooth fibers
from the neck of the bladder. The external urethral sphincter, however, is a distinct
structure distal to this region.
180
Urethra in male
male, the urethra is considerably longer, and can be divided into 3 parts: the
prostatic urethra, the membranous urethra, and the spongy urethra. The prostatic
urethra is surrounded by the prostate gland. The posterior surface of the prostatic
urethra is marked by the many openings of the prostatic ductules and the openings of
the ejaculatory ducts. The membranous urethra is the short stretch of tubing found
between the prostatic urethra and the bulb of the penis. It is surrounded by the sphincter
urethrae muscle. The spongy urethra is found within the bulb and corpus spongiosum
of the penis.
181
Ductus deferens
ductus deferens (previously
called the vas deferens) is the
continuation of the epididymis. It
enters the abdomen within the
spermatic cord, and enters the true
pelvis along its lateral walls just
deep to the peritoneum. As it
passes along the base of the
bladder it enlarges into a region
known as the ampulla. Posterior
to the base of the bladder, the
ampulla meets and fuses with the
duct of the seminal vesicle to form
the ejaculatory duct. A
vasectomy, which involves
ligation and removal of a section
of the ductus deferens, is a
common method of sterilization.
182
Seminal vesicles and ejaculatory ducts
glands are between the bladder and the rectum. The seminal vesicles do not store
semen, as their name implies. Instead, they are the principal source of seminal fluid,
producing fructose for the primary energy source for sperm, and prostaglandins that
stimulate muscle contraction in the uterus and uterine tubes to move the ovum. They
empty into a short duct at their inferior end, which in turn fuses with the ampulla of the
ductus deferens to form the ejaculatory ducts. The ejaculatory ducts empty into the
prostatic urethra
183
Prostate
In young men the prostate is a walnut-sized gland that surrounds the prostatic urethra
between the bladder and the bulb of the penis. It generates approximately 20% of the
seminal fluid, which enters the urethra through 20-30 ducts in its posterior wall.
Prostatic secretions are alkaline to counteract the acidic environment of the vagina,
contain zinc which stabilizes sperm chromatin, and prostate-specific antigen (PSA) that
keeps the fluid from coagulating
184
Why can the prostate be palpated
The posterior surface of the
prostate is in contact with the rectum, where it can be palpated during a rectal
examination. The prostate enlarges with age, and can obstruct the flow of urine. Benign
prostatic hypertrophy leads to nocturia (the need to void at night) and dysuria (pain
during urination). This disease occurs in 80% of men over the age of 80 years. Prostatic
carcinoma is also common, occurring in 30% of men over the age of 75 years.
185
Vagina
muscular tube that extends from the vaginal vestibule to the cervix of
the uterus. It lies posterior to the bladder and anterior to the rectum, and passes through
the pelvic diaphragm.
186
Fornix of vagina
The fornix is the recess formed around the cervix (see figures on
next two pages). The posterior wall of the fornix is thin and formed in part by
peritoneum; damage can result in peritonitis. Several muscles can act as vaginal
sphincters, including the levator ani, the sphincter urethra, and the bulbospongiosus
muscles.
187
Uterus
flexed anteriorly over the superior wall of the bladder at a right
angle to the vagina. It has several parts. The main part is the body, which narrows down
to form the cervix. The region where the body meets the cervix is called the isthmus.
The superior part of the body, between the entrances of the uterine tubes, is called the
fundus. The uterus has a vesical surface that is related to the bladder, and an intestinal
surface.
188
Broad ligament of the uterus
is composed of folds of peritoneum, suspends
the body and allows it to move posteriorly as the bladder fills
189
Vesicouterine pouch and rectouterine pouch
The pocket-like
projection of the peritoneal cavity between the uterus and bladder is the vesicouterine
pouch (A). The rectouterine pouch (B) is found between the uterus and rectum, and
extends inferiorly to the posterior wall of the vaginal fornix.
Clinical Correlate: Blood (e.g., from a uterine tube that has burst as the result of an
ectopic pregnancy) can pool in the vesicouterine and rectouterine pouches and can be
palpated during a vaginal exam. Note how the posterior fornix of the vagina is closely
related to the rectouterine pouch.
190
Wall of uterus
1) perimetrium, composed of peritoneum and
pelvic visceral fascia; 2) myometrium, composed of smooth muscle; and 3)
endometrium, the mucous coat that is sloughed off each month during menstruation.
The blood supply of the body of the uterus comes from the uterine arteries, which are
branches of the internal iliac artery, as well as from the ovarian arteries, which are
derived from the aorta.
191
Ovaries
almond-shaped organs that lie near the lateral walls of the true pelvis.
Their anterior surface is attached to the posterior surface of the broad ligament by a fold
of peritoneum called the mesovarium.
192
Suspensory ligament of ovary
Anchor ovary to lateral walls of the pelvis
A fold of broad ligament
Ovarian vessels and nerves pass through the suspensory ligament and
mesovarium to reach to ovaries
193
Ligament of the ovary
. A band of connective tissue, the ligament of the ovary,
anchors each ovary to the uterus, and a specialized fimbrium (fimbria ovarica) anchors
the ovary to the infundibulum of the uterine tube. The ovaries lie within the peritoneal
cavity. The ovaries usually atrophy following menopause, and are thus quite small in
most female cadavers.
194
Uterine tubes
Connect uterus with peritoneal cavity near each ovary
is composed of a uterine part, an isthmus, the ampulla, and the infundibulum.
The uterine part is surrounded by the myometrium of the uterus. The isthmus is the
short, thick-walled portion of the tube near the uterus. The ampulla is the longest part
of the tube, and is usually the site of fertilization. The infundibulum is the distal, funnel-
shaped portion of the uterine tube that opens to the peritoneal cavity. The abdominal
opening is surrounded by finger-like projections (fimbriae) that sweep up oocytes into
the uterine tube.
195
Why can infections in the vagina spread to the peritoneal cavity
The direct connection between the peritoneal cavity and the outside world via the female
internal genitalia means that infections in the vagina can spread to the peritoneal cavity and result in peritonitis. If the zygote is unable to pass into the uterus following
fertilization, it may implant in the walls of the uterine tube. Ectopic tubal pregnancies
may result in rupture of the uterine tubes, a potentially lethal condition.
196
Broad ligament
Itself is like a sheet thrown over the uterine tubes
197
Mesosalpinx
Between ovary and the uterine tube
198
Mesovarium
Ovary itself is anchored to the rest of the broad ligament
199
Ligamentum Teres (ROUND LIGAMENT of the uterus)
ligamentum teres originates near the fundus of the uterus,
passes laterally to the wall of the true pelvis, and exits the abdominal cavity through the
deep ring of the inguinal canal.
Cord of connective tissue
200
Ovarian ligament
The ovarian ligament, in contrast, is quite short. It
originates near the fundus and attaches to the uterine surface of the ovary.
201
Ligamentum Teres and ovarian ligament are remnants of
Gubernaculum- The
ligamentum teres and ovarian ligament are the remnants of the gubernaculum—the
cord-like structure that helps to pull the ovaries into the pelvis from the posterior
abdominal wall in the embryo
202
What serves as conduit for the ovarian vessels
The lateral surface of the ovary is attached to the lateral
walls of the pelvis by the suspensory ligament of the ovary, which also serves as the
conduit for the ovarian vessels
203
Branches of internal iliac artery supply
Pelvic viscera, perineum, medial thigh, and gluteal region
204
External iliac artery is principal for
Blood supply to lower limb
205
Divisions of internal iliac artery
two divisions: anterior (visceral) and posterior (parietal). The most constant vessels from the
anterior division include (in the most common order in which they are formed) the umbilical
artery, the obturator artery (to the medial thigh), the inferior vesical artery (males only), the
vaginal artery (females only), the uterine artery (sometimes a branch of the umbilical artery),
the middle rectal artery, the internal pudendal artery (to the perineum), and the inferior gluteal
artery (to the buttocks). The major branch of the posterior division is the superior gluteal
artery (also to the buttocks).
e umbilical artery has many branches,
including the superior vesical arteries, which supply the bladder. The umbilical artery becomes
the medial umbilical ligament as it approaches the anterior abdominal wall. The ureter is at
risk of being damaged when blood vessels are clamped off during hysterectomy or ovariectomy
206
Perineum
external surface region in the most inferior part of the trunk found between
the thighs and buttocks. When the thighs are abducted, the perineum is shaped like a diamond.
The anterior point of the diamond is the pubic symphysis and the posterior point is the tip of
the coccyx. The lateral points of the diamond are the ischial tuberosities. The perineum is
separated from the pelvic cavity by the pelvic diaphragm.
207
UG triangle
región bounded by the pubic symphysis and the ischial tuberosities.
Its most prominent components are the terminal part of the urethra and the external genitalia.
208
Anal triangle
triangle formed by the tip of the coccyx and the ischial tuberosities. It
contains the anal canal, associated vessels and nerves, and fascia.
209
Perineal body
tendinous center of the
perineum, found at the midpoint of the line drawn between the ischial tuberosities. Many
muscles attach to the perineal body, including the levator ani, bulbospongiosus, external anal
sphincter, and external urethral sphincter. The perineal body can be damaged during a difficult
childbirth, an injury (if not repaired) that may result in the prolapse of pelvic viscera.
210
Anal canal
is the most inferior part of the large intestine. It begins at the angle
formed by the puborectal sling and ends at the anus
211
Anal columns
. The inner lining of the superior
part of the anal canal is thrown into a series of longitudinal folds
Richly vascularized
End inferiorly in a series of semilunar VALVES
212
Supply above the pectinate line
blood is supplied by the superior rectal vessels and innervation is by
autonomic nerves
213
Supply below pectinate line
. Below the pectinate line, blood supply is by the inferior rectal vessels
and innervation by the inferior rectal branch of the pudendal nerve
214
Internal hemorrhoids
varicosities (dilations) of the veins found within the anal
columns superior to the pectinate line. The mucosa covering this part of the anal canal
is innervated by autonomic nerves and is insensitive to pain. Internal hemorrhoids can
therefore go undetected for a long time.
215
External hemorrhoids
varicosities of the veins found in the wall of the anal canal inferior to the pectinate line.
The lining of the inferior part of the anal canal is richly innervated by the inferior rectal
nerves—branches of the pudendal nerve. Since this is a somatic nerve, the inferior part
of the anal canal is very sensitive to pain
216
Why can hemorrhoids occur
inferior rectal vein drains blood
from the inferior part of the anal canal into the internal iliac vein, the wall of the anal
canal is a site of portacaval anastomosis. Hemorrhoids are usually the result of a
weakening of the anal canal from sitting too long, but they may also be an indication of
increased pressure in the valveless portal system
217
What is the Puborectal sling is part of
External anal sphincter
supplied by the inferior rectal nerve, a branch of the pudendal nerve. The internal
anal sphincter is a ring of smooth muscle innervated by parasympathetic fibers from the
pelvic splanchnic nerves
218
Rectum
continuation of the sigmoid colon. It begins at S3, where it lies
deep to the peritoneum (i.e., the rectum is a retroperitoneal organ). The rectum
continues down the anterior surface of the sacrum until it makes a right angle at the site
of the puborectal sling, which is formed by the puborectalis portion of the levator ani
muscle. Inferior to this angle is the anal canal.
219
Where are feces stored
Feces are stored primarily in the highly
distensible inferior third of the rectum in a region called the ampulla.
220
What are the transverse rectal folds for
Maintain continence
221
Male UG triangle
scrotum, penis, the membranous urethra,
and the superficial perineal muscles. The penis and
superficial perineal muscles will be considered
here.
222
Penis
root, body, and glans. It
is largely composed of spongy erectile
tissue called the corpus spongiosum
penis and the corpus cavernosum penis.
The corpus spongiosum penis is
expanded proximally (in the root) to
form the bulb of the penis. The urethra
pierces the bulb and continues within the
corpus spongiosum penis to the external
urethral orifice. The corpus
spongiosum penis is found along the
ventral midline of the body of the penis.
It expands distally to form the glans.
There are two corpora cavernosa found
dorsally and on either side of the corpus
spongiosum penis in the body of the
penis. In the root, the corpora cavernosa
separate into the left and right crura
(legs; singular crus) of the penis, which
are attached to the inferior pubic rami.
223
What are the most prominent arteries to supply penis
Dorsal arteries
Between corpora cavernosa and the deep arteries which run WITHIN the corpora cavernosa
Branches of internal pudendal aa
224
What drains into the erectile tissue of the penis
A plexus
of veins surrounds and drains the
erectile tissue of the penis and empties
into the deep dorsal vein of the penis.
225
Bulbospongiosus m associated with
Bulb of penis in male
Bulb of the vestibule in female
226
Contraction of bulbospongiosus m in male
contraction aids in the expulsion of semen or urine from the urethra, and can also aid
penile erection by inhibiting the flow of blood through the deep vein of the penis.
227
Bulbospongiosus m in female
In
women, the bulbospongiosus muscles run on either side of the vagina from the perineal
body to the clitoris. They can act as a vaginal sphincter and contribute to the external
urethral sphincter.
228
Ischiocavernosus m in male
In men, the ischiocavernosus muscles surround the crura. Their contraction forces blood
from the root into the body of the penis, thus helping to maintain erection. They also
assist the bulbospongiosus in restricting venous drainage of the penis.
229
Ischiocavernosus m in female
In women, the
ischiocavernosus muscles run along the inferior rami and insert on the crura of the
clitoris (see below). They play a role in the erection of the clitoris during sexual arousal.
The superficial perineal muscles are innervated by branches of the pudendal nerve.
230
Vulva
composed of the mons pubis,
labia majora, labia minora, vestibule of the vagina, clitoris, bulb of the vestibule, and greater
vestibular glands
231
Mons pubis
composed of the mons pubis,
labia majora, labia minora, vestibule of the vagina, clitoris, bulb of the vestibule, and greater
vestibular glands
232
Labia majora
crescent shaped folds of skin that cover and protect the labia
minora, the vaginal orifice and the urethral orifice.
233
Pudendal cleft
The slit-like opening found between the
labia majora is called the pudendal cleft
234
Scrotum homologous w
Labia majora
. Both
develop from the labioscrotal folds; these fuse in the male and remained unfused in the female.
235
Labia minora
lie deep to the labia majora. They cover the vestibule of the vagina and contain
spongy tissue that will become engorged with blood during the sexual response. Anteriorly
they fuse to the clitoral hood or prepuce; inferiorly they usually fuse as a fold of skin known as
the frenulum
236
Greater vestibular glands
Within the vaginal vestibule
are the urethral orifice, the vaginal orifice, and the openings of the ducts of the greater
vestibular glands. These glands secrete a mucus that lubricates the labia and the vestibule
during sexual arousal
237
Bulbs of the vestible
l. Deep to the bulbospongiosus muscles on either side of the vaginal
orifice, and partly within the labia minora, are the bulbs of the vestibule. The bulbs are
composed of spongy tissue similar to that found in the penis. When the bulbospongiosus
muscles contract during the sexual response, there is some evidence that they force blood from
the bulbs into the crura of the clitoris to help maintain erection.
238
Clitoris
Erectile organ
The clitoris is an erectile organ.
It is composed of two corpora cavernosa that form crura along inferior pubic rami, and which
are bound together superiorly to form the body of the clitoris. At the distal end of the body is
a small, rounded glans.
239
What happens when the pudendal nerves exit the pudendal canal
Pudendal nerve divides into several perineal nerves and dorsal nerve for the clitoris
Principle sensory nerves of the vulva
241
Supraorbital. Notch/foramen
Transmits the Supraorbital nerve (branch of CN V1) and vessels
242
Supraorbital notch , foramen
transmits the supraorbital nerve (a branch of CN V1)
and vessels
243
Infraorbital foramen
transmits the infraorbital nerve (a branch of CN V2) and vessels
through the maxilla
244
Boundaries of orbit
a. lateral—zygomatic and frontal bones
b. inferior—maxilla and zygomatic bones
c. medial—maxilla, lacrimal, and frontal bones
245
Bones within the orbit
a. frontal
b. ethmoid
c. sphenoid
d. lacrimal
e. maxilla
f. zygomatic
246
Openings of the orbit
superior orbital fissure
b. inferior orbital fissure
c. optic canal
247
Zygomatic bone - cheek bone
1. Articulates with the maxilla, frontal and temporal bones.
2. Lateral articulation with the temporal bone forms the zygomatic arch.
248
Nose
1. Nasal bones
2. Maxillae
3. Piriform aperture
4. Nasal septum
a. anteriorly—cartilage
b. posteriorly—ethmoid and vomer bones
249
Maxilla
1. Body (contains maxillary sinus)
2. Zygomatic process
3. Frontal process
4. Palatine process (horizontal)
5. Alveolar process
250
Mandible
Body—mental foramen transmits the mental nerve (a branch of CN V3)
2. Angle
3. Ramus
4. Coronoid process
5. Condylar process
251
Sagittal suture
2 parietal bones
252
Lambdoid suture
Occipital bone and the 2 parietal bones
253
Pterion
landmark for the region where the sphenoid, frontal, parietal, and temporal bones
all come together.
254
Anterior cranial fossa
Landmarks
contains the frontal lobes of the cerebral hemispheres (frontal poles)
formed by the frontal bone in front, the sphenoid bone behind (lesser wings)
divided medially by the crista galli and cribriform plates of the ethmoid bone
its floor forms the roofs of the orbits
2. Cranial foramina and neurovascular structures they transmit
• cribriform plate—olfactory nerves
255
Middle cranial fossa landmarks
Landmark
- contains the anterior parts of the temporal lobes of the cerebral hemispheres
- formed by the sphenoid bone (greater wings) in front and the temporal bone
behind
- divided medially by the body of the sphenoid bone, whose upper part is the sella
turcica (Turkish saddle), which contains the pituitary gland
- its floor (petrous part of the temporal bone) roofs the chambers of the middle
and inner ear
- A common site for basilar skull fractures
256
Optic canal transmits
Ophthalmic artery
Optic nerve CN2
257
Superior orbital fissure
Cn3- oculomotor nerve
Trochlear n- cn4
Opthalmic division of trigeminal CN V1
Abducens nerve CN 6
258
What contains the internal carotid artery
Carotid groove
259
Foramen rotundum
Maxillary division of trigeminal CNV2
260
Foramen ovale
Mandíbular division of trigeminal V3
261
Foramen Spinosum
Middle meningeal artery —grooves the inner surface of the squamous
portion of the temporal bone. The middle meningeal artery can be torn
when the temporal bone is fractured, producing an epidural hematoma.
262
Foramen lacerum
filled by cartilage, which is absent in the dried skull
263
Landmarks of posterior cranial fossa
contains the cerebellum, pons, and medulla
formed by the temporal bone and sphenoid bone in front, and the occipital bone
behind
divided medially by the foramen magnum
its floor and posterior walls are grooved for the dural venous sinuses
264
Difference between cranial and spinal nerves
Besides their origin from the brain and brainstem, one of the major differences between the
spinal and cranial nerves lies in their function. While all spinal nerves contain both sensory
and motor fibers, the cranial nerves are less uniform. Some of the cranial nerves are purely
sensory, others are purely motor, and others are mixed.
265
Parasympathetic innervation
3,7, 9 , 10 carry preganglionic parasympathetic
nerves, which synapse in parasympathetic ganglia. Cranial nerves do NOT carry
sympathetic fibers. The parasympathetic ganglia for CNs III, VII, and IX are found in the
head and neck; their postganglionic fibers travel via branches of CN V to supply their target
structures. Parasympathetic ganglia for CN X are scattered throughout the thorax and
abdomen, near the organs that they innervate.
266
Course of olfactory n
Nasal cavity to cribriform
plate of the ethmoid bone
→ brain
Distribution or function
Nasal mucous membrane
Smell
267
Optic nerve
Retina → optic foramen →
optic canal → optic chiasm
→ optic tract → brain
Distrib:
Retina of the eye
Func:
Vision
268
Oculomotor 3
Lateral wall of cavernous
sinus → superior orbital
fissure → orbit
One muscle of the upper eyelid
• Levator palpebrae superioris
Four muscles of the eyeball
• 3 recti: superior, medial and inferior
• 1 oblique: inferior
Carries preganglionic parasympathetic fibers, which
end in the ciliary ganglion. Postganglionic fibers
supply 2 intrinsic smooth muscles of the eye:
sphincter pupillae and ciliaris muscles
269
Trochlear
Same as CNIII: lateral
wall of cavernous sinus →
superior orbital fissure →
orbit
Superior oblique muscle
270
V1- ophthalmic
Same as CN III and IV:
lateral wall of cavernous
sinus → superior orbital
fissure → orbit
Major branches :
Frontal
• Supratrochlear
• Supraorbital
Nasociliary
Distrib:
Skin of the face, scalp
Cornea
Mucosa of the nasal cavity
271
V2-maxillary
Cavernous sinus—-foramen rotundum—inferior orbital fissure —- infraorbital foramen——face
Major branches :
Zygomatic, superior alveolar, infraorbital
Mucosa of the nasal cavity, part of the pharynx
(nasopharynx), and palate
Skin over the temple and bony part of the cheek.
Gums and teeth of the upper jaw, maxillary sinus
Skin of the face (lower eyelid, nose, upper lip)
272
V3-mandibular
Foramen ovale—— infratemporal fossa
Meningeal
Motor
Lingual
Inferior alveolar
• Mental nerve
Meninges
Tensor tympani, tensor veli palatini, and the muscles
of mastication: masseter, temporalis, medial and
lateral pterygoids
Mucosa of the oral cavity, mucosa of the anterior 2/3
of the tongue (general sensory). Carries
parasympathetic fibers from the chorda tympani
branch of CN VII to the submandibular ganglion.
Postganglionic fibers innervate the submandibular and
sublingual glands.
Gums and teeth of the lower jaw
Skin of the face over the chin
273
Abducens 6
Cavernous sinus—- superior orbital fissure— orbit
Distrib- lateral rectus muscle
274
Supraorbital margin
Frontal bone
275
Olfactory nerve dysfunction
Reduction or loss of smell.
276
Optic nerve dysfunction
Visual deficits in the corresponding eye.
277
Oculomotor nerve dysfunction
Downward and outward deviation of the eyeball due to unopposed pulls of LR and SO.
Double vision due to images falling on non-corresponding regions on the two retinae.
Ptosis from paralysis of LPS.
Dilated pupil with loss of accommodation due to paralysis of sphincter and ciliary muscles.
278
Trochlear nerve dysfunction
Difficulty in depressing the adducted eye.
Double vision.
279
Trigeminal nerve dysfunction
Loss of sensations in the face; loss of corneal blink reflex; difficulty in chewing.
280
Abducens nerve dysfunction
Failure to abduct the affected eye due to paralysis of LR.
Double vision.
281
Facial nerve dysfunction
Inability to raise the eyebrow, wrinkle the forehead, close the eye, and elevate the corner of the mouth on smiling.
282
Vestibulocochlear nerve dysfunction
Problems in hearing and maintaining balance.
283
Glossopharyngeal nerve dysfunction
Loss of gag reflex and taste in the posterior third of the tongue.
Difficulty swallowing (dysphagia).
284
Vagus nerve dysfunction
Difficulty in swallowing and speaking (dysphonia).
When patient is asked to open the mouth and say 'ah,' the palatal arch on the affected side will fail to rise and the uvula will deviate to the normal side.
285
Accessory nerve dysfunction
Weakness of the sternocleidomastoid and trapezius muscles of the same side, detected when the patient shrugs the shoulders or turns the head to one side, against resistance.
286
Oral cavity
extends from the lips to the junction between the oral cavity and the oropharynx.
The palatoglossal arches designate the posterior boundary between the oral cavity and the
oropharynx.
287
Intrinsic mm of the tongue
intrinsic muscles consist of longitudinal,
transverse, and vertical fibers that act together to alter the shape of the tongue. These
muscles are not attached to bone
288
Extrinsic mm of tongue
he extrinsic muscles are attached to bone and the
soft palate; they move the tongue as a whole
289
Vallate papillae
which are arranged along
a V-shaped sulcus separating the anterior 2/3 from the posterior 1/3 of the tongue.
These are innervated by CN IX.
290
Frenulum of tongue
connects the inferior aspect to the floor of the mouth. On
each side of the frenulum is a small papilla marking the opening of the duct from the
submandibular gland
291
Genioglossus
extends from the mandible anteriorly to the hyoid bone and the
dorsum of the tongue; protrudes the tongue by pulling the base forward (then the
intrinsic muscles protrude the tip)
292
Hyoglossus
from the hyoid bone to the side and inferior aspect of the tongue;
depresses and retracts tongue.
293
Styloglossus
from styloid process; inserts and acts with the hyoglossus to
elevate and retract the tongue and form a trough for swallowing.
294
Palatoglossus
from soft palate to side of the tongue; elevates posterior aspect
of tongue
295
Nasal cavities
serve to warm and humidify air, and to remove particulate matter in the air
prior to its reaching the trachea and lungs. The two nasal cavities are separated from each other
by the nasal septum, which is formed by the perpendicular plate of the ethmoid bone
posterosuperiorly, the vomer posteroinferiorly, and the septal cartilage anteriorly. They extend
from the nares anteriorly to the choanae posteriorly where they open into the nasopharynx.
296
Above superior nasal concha
Sphenoethmoidal recess
297
Olfactory region
located in the mucosa of the upper ⅓ of the lateral wall and nasal
septum. Nerve endings from these regions pass through the cribriform plate of the ethmoid
bone and into the olfactory bulb
298
frontal, maxillary, and ethmoid sinuses
are paired but
Not always symmetric
299
What drains into hiatus semilunares
frontal, maxillary,
and anterior ethmoidal sinuses drain here
300
What sinus more susceptible to infection
cavity of the maxillary sinus lies
below the hiatus, so this sinus drains less well in the upright position. This arrangement makes the
maxillary sinus more susceptible to infection
301
Kiesselbach’s plexus
Branches of facial, ophthalmic, and maxillary arteries
anastomose on the anteroinferior portion of the nasal septum in Kiesselbach’s plexus;
it is here that nosebleeds frequently originate.
302
Path of 12
lossal canal → neck
All extrinsic and intrinsic muscles of the tongue, except
palatoglossus
303
Path of 11
men magnum →
jugular foramen → posterior
triangle of the neck
Motor
Sternocleidomastoid muscle
Trapezius
304
Path of 10
n → neck →
thorax → abdomen
All pharyngeal muscles, except stylopharyngeus.
All palatine muscles, except tensor veli palatini.
Pharyngeal
Superior laryngeal
• Internal laryngeal
• External laryngeal
Cardiac
Recurrent laryngeal
Mucosa of the larynx from the inlet down to the vocal
cords.
Cricothyroid muscle
Ends in the ganglia of the cardiac plexus.
Postganglionic fibers supply parasympathetic
innervation to the heart.
Mucosa of the larynx below the level of the vocal cords.
All laryngeal muscles, except cricothyroid.
Parasympathetic branches to thorax and abdomen
305
Branches of 9
Carotid
Parasympathetic
Motor
Terminal branches
Carotid sinus and body
Preganglionic parasympathetic to the otic ganglion;
from the otic ganglion to parotid gland via a branch of
CN V3.
Stylopharyngeus muscle
Mucosa of the pharynx (oropharynx and
laryngopharynx)
Mucosa of the posterior 1/3 of the tongue (general
sensory and taste)
306
Branches of 8
Vestibular
Cochlear
Special sensory structures in the ear
Hearing and equilibrium
307
Branches of 7
ic to
lacrimal gland
Chorda tympani
Supplies preganglionic parasympathetic fibers to the
pterygopalatine ganglion, from which postganglionic
fibers travel through branches of CN V1 and V2 to
reach the lacrimal gland.
Passes through the middle ear cavity and exits into the
infratemporal fossa. It joins the lingual branch of CN
V3. Carries preganglionic parasympathetic fibers,
which end in the submandibular ganglion.
Postganglionic fibers are distributed through the lingual
nerve to the submandibular and sublingual salivary
glands. Also carries taste sensation from the anterior
2/3 of the tongue.
Muscles of facial expression
Terminal branches:
temporal, zygomatic,
buccal, mandibular, and cervical
308
Hypoglossal nerve dysfunction
Paralysis and atrophy of the tongue on the corresponding side.
When patient is asked to protrude the tongue, the tongue will deviate to the paralyzed side.
