Download 2 - The Abdomen (tutors)

The Abdomen
Surface Topography of the Abdomen:
Quadrants and Their Contents: Divided by Transumbilical plane (L3/L4) and Median Plane Intersection
Right Upper Quadrant: liver and gallbladder
Right Lower Quadrant: cecum and appendix (at
McBurney’s Point between ASIS and umbilicus)
Left Upper Quadrant: stomach and spleen
Left Lower Quadrant: descending colon and
sigmoid colon
Nine Region Pattern: Intersections of 2 Midclavicular Planes, Subcostal Plane (below costal cartilage of
rib 10), and Intertubercular Plane (tubercles of iliac crests)
Right Hypochondrium
Right Flank
Right Groin (Inguinal)
Epigastric
Umbilical
Pubic
Left Hypochondrium
Left Flank
Left Groin (Inguinal)
Primitive Gut Region
Adult Gut Region
Foregut
Distal esophagus, stomach,
proximal duodenum, liver,
pancreas, and gallbladder
Supplying Artery/Lymphatics/
Innervations/ and Referred Pain
Celiac
Epigastric region
Parasympathetic: Vagus Nerve
Celiac Pre-aortic nodes
Superior Mesenteric
Umbilical region
Parasympathetic: Vagus Nerve
Superior mesenteric Pre-aortic
nodes
Inferior Mesenteric
Pubic region
Parasympathetic: Pelvic
Splanchnic Nerves
Inferior mesenteric Pre-aortic
nodes
Gut Derivatives:
Midgut
Hindgut
Distal duodenum, jejunum,
ileum, cecum, appendix,
ascending colon, and proximal
2/3 of transverse colon
Distal 1/3 of transverse colon,
descending colon, sigmoid colon,
rectum, and upper anal canal
Skeletal Components of the Abdominal Wall
-
5 lumbar vertebrae and their intervertebral discs
Superior expanded parts of pelvic bones
Inferior thoracic wall: costal margin, rib 12 and end of rib 11, and the xiphoid process
Muscles of the Abdominal Wall
Muscle
Quadrates lumborum
Psoas major
Psoas minor
Iliacus
Transversus abdominis
Internal oblique
External oblique
Rectus abdominis
Pyramidalis
Attachment
Innervation
Transverse processes of L5,
iliolumbar ligament, and iliac
Anterior rami of
crest to transverse processes
T12 and L1 to L4
of L1 to L4 and inferior border
of rib 12
Bodies and intervertebral discs
of T12-L5, transverse processes Anterior rami of
of L1-5 to lesser trochanter of
L1 to L3
femur
Bodies and intervertebral discs
of T12 and L1 to pectineal line Anterior rami of
of pelvic brim and iliopubic
L1
eminence
Iliac fossa, anterior sacroiliac
and iliolumbar ligaments, and
Femoral Nerve
upper lateral sacrum to lesser
(L2 to L4)
trochanter of femur
Thoracolumbar fascia, iliac
crest, lateral 1/3 inguinal
ligament, costal cartilages of
Anterior rami of
ribs 7-12 to linea alba, pubic
T7 to T12 and L1
crest, and pectineal line
Thoracolumbar fascia, iliac
crest, and lateral 2/3 inguinal
ligament to inferior border of
Anterior rami of
lower 3 ribs, linea alba, pubic
T7 to T12 and L1
crest, and Pectineal line
Outer surface of ribs 5-12 to
lateral lip of iliac crest and
linea alba
Pubic crest, pubic tubercle, and
pubic symphysis to costal
cartilages of ribs 5-7 and the
xiphoid process
Front of pubis and pubic
symphysis to linea alba
Anterior rami of
T7 to T12
Anterior rami of
T7 to T12
Anterior ramus
of T12
Action
Depress and stabilize rib
12 and some lateral
bending of trunk
Flex thigh at hip
Weak flexion of lumbar
vertebral column
Flexion of thigh at hip
Compress abdominal
contents
Compress abdominal
contents, bilaterally flex
trunk, unilaterally bend
trunk to same side and
turn anterior part of
abdomen to same side
Compress abdominal
contents, bilaterally flex
trunk, unilaterally bend
trunk to same side and
turn anterior part of
abdomen to same side
Compress abdominal
contents, flex vertebral
column, and tense
abdominal wall
Tenses the linea alba
Ligaments of the Abdomen
Ligament
Inguinal Ligament
Lacunar Ligament
Pectineal (Cooper’s) Ligament
Attachments
ASIS and Pubic Tubercle
Extends from medial inguinal
ligament that pass backward to
attach to pecten pubis
From lacunar ligament to pecten
pubis of pelvic brim
Significance
Formation of inguinal canal
Major Arteries of the Abdomen
Artery
Celiac
Superior mesenteric
Inferior mesenteric
Branches From
Anterior Aorta at L1
Anterior Aorta at L2
Anterior Aorta at L3
Supplies
Foregut
Midgut
Hindgut
Left Gastric
Celiac Trunk (smallest
branch)
Abdominal esophagus
and surfaces of stomach
Celiac Trunk (largest
branch)
Spleen, neck/body/tail
of pancreas, fundus of
stomach (short gastric
arteries)
Splenic Artery
Common Hepatic Artery
Inferior
Pancreaticoduodenal a.
Jejunal and Ileal
Arteries
Middle Colic Artery
Celiac Trunk (medium
size branch)
Liver, pancreas,
gallbladder, surface of
stomach and greater
omentum (right gastroomental a.), duodenum
Superior Mesenteric
Artery
Head and uncinate
process of the pancreas
and the duodenum
Superior Mesenteric
Artery (left side)
Jejunum and ileum
Superior Mesenteric
Transverse colon
Significance
Anastomoses with right
gastric a. and
esophageal branches
from thoracic aorta
Gives off left gastroomental a. that
anastomoses with the
right gastro-omental a.
Divides into Hepatic
artery proper (right
(gives of cystic a.) and
left hepatic aa.) and
Gastroduodenal artery
(to the right gastroomental and posterior
and anterior superior
pancreaticoduodenal
aa.)
Splits into anterior and
posterior inferior p-d aa
that anastomose with
the anterior and post
superior p-d aa.
Pass between 2 layers
of mesentery and form
anastomosing arches
and the vasa recta that
give the final direct
supply to the walls of
the small intestine
Enters the transverse
Artery (1st branch from
right side)
Right Colic Artery
Superior Mesenteric
Artery (2nd branch from
right side)
Ascending colon
Ileocolic Artery
Superior Mesenteric
Artery (3rd branch from
right side)
Ascending colon,
cecum, appendix, and
final portion of ileum
mesocolon and
branches to right and
left middle colic aa.
Anastomoses with
ileocolic and middle
colic aa.
Divides into superior
(anastomose with right
colic a.) and inferior
(colic, cecal,
appendicular, and ileal
branches) branches.
Divides into ascending
and descending
branches and
anastomoses with 1st
sigmoid artery
Anastomoses with left
colic a. and superior
rectal artery branches
Anastomose with
middle rectal aa. And
inferior rectal aa.
Left Colic Artery
Inferior Mesenteric
Artery (1st branch)
Sigmoid Arteries
Inferior Mesenteric
Artery (2 to 4 branches)
Upper descending colon
and distal transverse
colon (ascending),
lower descending colon
(descending)
Lower descending colon
and sigmoid colon
Superior Rectal Artery
Inferior Mesenteric
Artery (terminal branch)
Rectum and internal
anal sphincter
Musculophrenic artery
Internal thoracic artery
Superficial Superior
abdominal wall
Superficial epigastric
and Superficial
circumflex iliac artery
Femoral artery
Superficial Inferior
abdominal wall
Internal thoracic artery
Deep superior
abdominal wall
Deep lateral abdominal
wall
External iliac artery
Deep inferior
abdominal wall
Superficial and inferior
epigastric arteries enter
rectus sheath and
anastomose
Drains
Significance
Spleen, pancreas,
gallbladder, abdominal
part of GI tract
Hepatic portal system.
Its right and left
branches enter the
liver.
Superior Epigastric
artery
10th and 11th intercostal
arteries and subcostal
artery
Inferior epigastric artery
and deep circumflex
iliac artery
Superficial and inferior
epigastric arteries enter
rectus sheath and
anastomose
Major Veins of the Abdomen
Vein
Portal Vein
Tributaries
Formed by splenic and
superior mesenteric
veins (at level of L2).
Right and left gastric
veins (lesser curvature
of stomach and
esophagus), cystic veins
gallbladder), paraumbilical veins (ab wall)
Short gastric veins, left
gastro-omental vein,
pancreatic veins,
inferior mesenteric vein
Jejunal, ileal, ileocolic,
right colic, middle colic,
right gastro-omental,
and anterior and
posterior inferior
pancreaticoduodenal
veins
Superior rectal vein,
sigmoid veins, and left
colic vein
Splenic Vein
Superior Mesenteric
Vein
Inferior Mesenteric
Vein
Spleen, greater
curvature of stomach
Hepatic portal system
Small intestine, cecum,
ascending colon, and
transverse colon
Hepatic portal system
Rectum, sigmoid colon,
descending colon, and
splenic flexure
Hepatic portal system
Lymphatic Drainage of the Abdomen:
-
Superficial drainage to axillary nodes (above umbilicus) and superficial inguinal nodes
(below umbilicus)
Deep drainage to parasternal nodes(along internal thoracic artery), lumbar nodes (along
aorta), and external iliac nodes (along external iliac artery)
Pre-aortic nodes (celiac, superior and inferior mesenteric) drain gut (GI tract, liver,
gallbladder, pancreas, and spleen)
Para-aortic nodes (right and left lateral aortic or lumbar nodes) drain the body wall, kidneys,
suprarenal glands, and the gonads
Right and Left Subclavian trunks: upper abdominal wall
Thoracic Duct: abdominal walls and viscera
Canals and Compartments
Canal/Compartment
Inguinal Canal
Spermatic Cord
Borders
Begins with deep inguinal ring and ends
with superficial inguinal ring. Aponeurosis
of external oblique (anterior wall),
transversalis fascia (posterior wall),
transversus abdominis and internal
oblique (roof), and inguinal ligament
(floor)
External spermatic fascia (aponeurosis of
external oblique), cremasteric fascia
(internal oblique), and internal spermatic
fascia (transversalis fascia)
Contents
Spermatic cord in men and the
round ligament of uterus and
genital branch of genitofemoral
nerve (L1/L2) in women
Ductus deferens, artery to ductus
deferens, testicular artery (from
aorta), pampiniform vein plexus,
cremasteric artery and vein,
genital branch of genitofemoral
nerve, sympathetic and visceral
afferent nerve fibers, lymphatics,
and remnants of processus
vaginalis
Abdominal Viscera: Intraperitoneal or retroperitoneal
Viscera
Esophagus
(abdominal
part)
Stomach
(4 regions:
cardia, fundus,
body, pylorus)
Duodenum
(4 parts: 1st
superior, 2nd
descending, 3rd
inferior, 4th
ascending)
Jejunum
Ileum
Large Intestine
(Sections:
cecum,
appendix,
ascending
colon,
Location
T10 (esophageal hiatus
through diaphragm) to
the cardiac orifice of the
stomach (left to midline)
Blood Supply/Nerve Supply
Esophageal branches from left gastric artery (from celiac
trunk) and esophageal branches from left inferior phrenic
artery (aorta)
Anterior vagal trunk (several small trunks, from left vagus
nerve) and the Posterior vagal trunk (single trunk from
right vagus nerve
Between the esophagus
and small intestine in the
epigastric, umbilical, and
left hypochondriac
regions
Left gastric artery (from celiac trunk), right gastric artery
(from hepatic artery proper), right gastro-omental artery
(from gastroduodenal artery), left gastro-omental artery
(from splenic artery), and the posterior gastric artery
(from splenic artery)
Between stomach and
jejunum, C-shaped, 2025cm long, above the
level of the umbilicus,
adjacent to head of
pancreas
Supraduodenal artery, duodenal branches from anterior
and posterior superior pancreaticoduodenal artery (all
from gastroduodenal artery), the anterior and posterior
inferior pancreaticoduodenal artery, and first jejuna
branch (all from superior mesenteric artery)
Between duodenum and
ileum, the proximal 2/5
of the small intestine,
mostly in the left upper
quadrant
Between the jejunum
and the cecum, the distal
3/5 of the small intestine,
mostly in right lower
quadrant
From right groin (as the
cecum) through right
flank, right
hypochondrium, crossing
abdomen to left
hypochondrium,
continuing down to left
Jejunal arteries from the superior mesenteric artery
Ileal arteries and ileal branch from ileocolic artery (both
from superior mesenteric artery)
To cecum and appendix: anterior and posterior cecal
arteries and appendicular artery from ileocolic artery
(from superior mesenteric artery), to ascending colon:
superior mesenteric artery branches, to transverse colon:
superior and inferior mesenteric artery branches, to the
descending and sigmoid colons: branches of inferior
mesenteric artery, to rectum and anal canal: branches of
transverse
colon,
descending
colon, sigmoid
colon, rectum,
and anal canal)
Liver
(4 lobes: right,
left, caudate,
and quadrate)
Gallbladder
(3 parts:
fundus, body,
neck)
Pancreas
(5 parts: head,
uncinate
process, neck,
body, and tail)
Spleen
Kidneys
flank and into left groin
Primarily in right
hypochondrium and
epigastric regions, rests
under the diaphragm,
protected by the rib cage
Found on the visceral
surface of the liver in a
fossa between the right
and quadrate lobes
Extends across the
posterior abdominal wall
from the duodenum to
the spleen, mostly
posterior to the stomach
Lies against diaphragm in
the area of rib 9 to 10 in
the left upper quadrant,
connected to the
stomach (by
gastrosplenic ligament)
and to the left kidney (by
the splenorenal ligament)
Lie in the posterior
extraperitoneal
connective tissue lateral
to vertebral column from
T11 to L3
inferior mesenteric artery and internal iliac artery
Right and Left hepatic arteries from hepatic artery proper
(from common hepatic artery from celiac trunk)
Cystic artery from the right hepatic artery (from hepatic
artery proper)
Gastroduodenal artery, anterior and posterior superior
and inferior pancreaticoduodenal arteries, dorsal
pancreatic artery, great pancreatic artery,
Splenic artery from the celiac trunk
Renal arteries (2) from lateral abdominal aorta
Renal arteries, branches from the abdominal aorta ,
testicular or ovarian arteries, and common and internal
iliac arteries
Ureters
Between the kidneys and
the urinary bladder,
Suprarenal
Glands
Superior pole of each
kidney
(Renal, aortic, superior hypogastric, and inferior
hypogastric plexuses. Visceral efferents (symp and para)
Visceral afferents return to T11-L2 (referred pain to
cutaneous areas of T11-L2: post/lat abdominal wall, pubic
region, scrotum, labia majora, prox. Ant. Thigh)
Inferior phrenic arteries (branch to superior suprarenal
arteries), middle suprarenal arteries, artery, and inferior
suprarenal arteries
Peritoneum:
Fold
Greater
Omentum
Lesser
Omentum
Mesentery
Transverse
Mesocolon
Sigmoid
Mesocolon
Location
Attaches to the greater
curvature of the stomach
and the first part of the
duodenum and travels
back upward to attach to
posterior abdominal wall
Extends from lesser
curvature of the stomach
and first part of the
duodenum to the inferior
surface of the liver
Connects jejunum and
ileum to the posterior
abdominal wall, passes
obliquely from
duodenojejunal junction
to ileocecal junction
Connects transverse colon
to posterior abdominal
wall
Attaches sigmoid colon to
abdominal wall, V shaped
with the apex near the
division of the left
common iliac artery into
internal and external
branches
Function/Significance
Derived from dorsal mesentery, can migrate to inflamed
areas of the bowel, important site for tumor spread
Derived from ventral mesentery, divided into the
hepatogastric and hepatoduodenal ligaments (encloses
hepatic artery proper, bile duct, and portal vein, and
forms anterior border of omental foramen), contains
right and left gastric vessels
Contains arteries, veins, nerves, and lymphatics that
supply the jejunum and the ileum
Contains arteries, veins, nerve, and lymphatics related to
transverse colon
Contains the sigmoid and superior rectal vessels, along
with nerves and lymphatics associated with the sigmoid
colon
Important Nerve structures and Innervations:
Structure
Parietal Peritoneum
Innervation
Somatic afferents of associated spinal nerves
Visceral Peritoneum
Visceral afferents that accompany autonomic nerves back
to CNS
Extrinsic: motor impulses from CNS and sensory impulses
to CNS (visceral afferents and efferents) Parasympathetic
from Vagus and Pelvic splanchnics
Intrinsic: enteric nervous system (sensory and motor)
organized into two plexuses (myenteric and submucosal),
regulates and controls secretary activities, GI blood flow,
and peristalysis. Can be modified by Sympathetics!
Abdominal GI Tract,
spleen, pancreas,
gallbladder, liver
Walls of GI tract
Referred Pain
No, well localized
Yes, poorly localized
discomfort and
reflex activity
Sympathetic Trunk:
-
Base of skull to coccyx
Composed of ganglia (neuronal cell bodies) and trunks
3 cervical, 11 or 12 thoracic, 4 lumbar, 4 or 5 sacral, and the ganglion impar at the coccyx
Trunks contain preganglionic and postganglionic sympathetic fibers and visceral afferents
Gray rami communicantes connect ganglia and trunks to adjacent spinal nerves
White rami communicantes present from T1 to L2
Splanchnic Nerves:
-
-
Innervate abdominal viscera
Thoracic, lumbar and sacral splanchnic nerves carry preganglionic sympathetic fibers and
visceral afferents
Pelvic splanchnic nerves carry preganglionic parasympathetic fibers (from S2-4)
Greater Splanchnic Nerve (Thoracic):T5-9, travels to celiac ganglion
Lesser Splanchnic Nerve (Thoracic): T10-11, travels to aorticorenal ganglion
Least Splanchnic Nerve (Thoracic): T12, travels to renal plexus
Lumbar Splanchnic Nerves (2 to 4 of them) enter the prevertebral plexus (extends from
aortic hiatus to right and left common iliac arteries) carrying preganglionic sympathetic
fibers and visceral afferents
Sacral Splanchnic Nerves enter the hypogastric plexus (pelvic plexus)
Pelvic Splanchnic Nerves: ONLY splanchnics that carry Parasympathetic fibers, originate
directly from anterior rami of S2-4, supplies the distal 1/3 colon transverse, descending
colon, and sigmoid colon with preganglionic parasympathetic fibers
Abdominal Prevertebral Plexus and Ganglia:
-
3 major divisions: celiac, aortic, and superior hypogastric plexuses
Receives preganglionic parasympathetic and visceral afferents from Vagus nerve,
preganglionic sympathetic and visceral afferents from thoracic and lumbar splanchnic
nerves, and preganglionic parasympathetics from the pelvic splanchnic nerves
Clinical Correlations:
Clinical Correlate
Indirect Inguinal
Hernia
Direct Inguinal
Hernia
Anatomy Involved
The herniated sac protrudes
through the deep inguinal
ring lateral to inf. epigastric
vessels, compressing the
structures within the
inguinal canal.
The herniated sac enters the
medial end of the inguinal
canal (at the inguinal
triangle) through a
weakened posterior wall
Patients Presents W/
Lump present in the
scrotum or labia
majorus
Lump present in groin
Misc.
Most common
More common in men
because of their larger
inguinal canal
Congenital (processus
vaginalis patent)
More common in
mature men
Acquired (weak muscles
or raised intraabdominal pressure)
Duodenal Ulcers
Meckel’s
Diverticulum
Stomach
Carcinoma
Appendicitis
Annular Pancreas
Gallstones
Jaundice
Superior part of duodenum,
either anteriorly( erode into
peritoneal cavity) or
posteriorly (erode into
gastroduodenal or posterior
superior
pancreaticoduodenal
arteries)
Remnant of the proximal
yolk stalk (vitelline duct)
that extends into the
umbilical cord and lies on
the antimesenteric border
of the ileum
Stomach wall, can be caused
by gastritis, pernicious
anemia, and polyps
appendix
Pancreas, duodenum.
Ventral bud of embryologic
pancreas splits and the 2
segments encircle the
duodenum
Gallbladder, bile ducts. The
stones are a mix of
cholesterol and bile pigment
that undergo calcification
Excess bilirubin in the blood
plasma, can be caused by:
conditions involving
excessive RBC breakdown
(hemolytic anemia),
inflammatory change within
the liver (hepatitis,
cirrhosis), poisons,
obstruction of biliary tree
(gallstones, tumor)
Peritonitis and
subdiaphragmatic gas
(anterior ulcer), or
internal bleeding
(posterior ulcer)
Bleeding,
intussusception,
diverticulitis, ulceration,
obstruction (symptoms
present in small
number of patients)
Vague epigastric pain,
early fullness with
eating, bleeding leading
to chronic anemia, and
obstruction
Pain begins as a central
periumbilical
intermittent pain that
develops into constant
localized pain in the
right groin. May have a
temperature, nausea,
and vomiting
Poor gastric emptying,
vomiting,
polyhydramnios, failure
to thrive
Referred pain in skin
over shoulder, jaundice
(bile flow obstructed)
Yellow discoloration of
the skin (best seen in
sclera of eyes)
Most common in
duodenal cap (1st part)
May be due to H. pylori
bacteria or excessive
acid production in
stomach
Occurs in about 2% of
population
Poor survival rates
Requires an
appendectomy
Congenital
More common in
women
Splenic disorders
(rupture and
enlargement)
Hepatic Cirrhosis
Diaphragmatic
Hernia:
Morgagni’s and
Bochdalek’s most
common
Hiatus Hernia
Rupture: localized
trauma to left upper
quadrant, left lower rib
fractures
Spleen and its vasculature
and lymphatic tissue
Liver tissue damaged by
toxins/virus/biliary
obstruction/ vascular
obstruction/ malnutrition/
and inherited disorders.
Portal hypertension leading
to varicose veins
Diaphragm (central tendon
and esophageal hiatus)
Morgagni’s: between
xiphoid process and costal
margins on the right
Bochdalek’s: on left where
the pleuroperitoneal
membrane fails to close the
pleuroperitoneal canal
Abdominal contents
(bowel) enters the
thoracic cavity and
reduces respiratory
function
Diaphragm, esophagus,
fundus of stomach
Acid reflux, pain in
epigastric region,
ulceration leading to
bleeding and anemia
Very common, about
20% of population
Kidney tissue, precipitates of
calcium, phosphate, oxalate,
urate, and other salts
Pain in infrascapular
region into the groin,
and possibly in scrotum
or labia majora, blood
in urine
Can become lodged at
the 3 constricted points
of the ureters:
ureteropelvic junction,
pelvic brim (where they
cross the common iliac
vessels), and their
entrance into the
bladder wall
Arises near intervertebral
discs, some infections like
tuberculosis and salmonella
discitis spread ant/lat and
infection seeps into the
psoas muscle and its sheath
Mass below inguinal
ligament
Kidney Stones
More common in
Men
Psoas muscle
abscess
Enlargement:
lymphadenopathy,
leukemia, lymphoma,
infections
Varicose veins
(hemorrhoids,
esophageal varices, and
caput medusa) ),
jaundice (buildup of
bilirubin) buildup of
toxins (leads to
neurological
symptoms), inadequate
blood clotting proteins
Huge blood supply to
the spleen: bleeds
profusely when
ruptured
Psoas sheath most
important out of any
muscle sheath