Org Ana: Abdominal Wall Flashcards
where is the abdomen located
region of the trunk that lies between the diaphragm and pelvic inlet
describe the structure of the abdomen
soft tissue region
little bony framework
has an intact abdominal wall for support of its contents
what are the common abdominal problems
acute pain
swellings
blunt and penetrating trauma
what are the boundaries of the abdomen
superior - diaphragm
inf - pelvic inlet
ant - lower part of thoracic cage and rectus abdominis, tranversus abdominis and fascia, external oblique
post - lumbar vertebrae and IV discs
lat - by the 12th rib and upper part of pelvis, iliacus, psoas, quadratus lumborum, aponeuroses of origin of transversus abdominis
what are the bones founded anteriorly at the abdominal wall
xiphoid process
costal margin - cc of rib 7-10
lower ribs
which organs do the bones of the anterior abdominal wall cover
liver, stomach, spleen, kidneys
what are the bones at the posterior of the abdominal wall
lumbar vertebrae - L1-L5
pelvis - Os coxae; ilium, ischium and pubis
what is the iliopectineal line
demarcates the true and false pelvis
what is the purpose of the posterior bones of the abdominal wall
attachment for muscles and some protection of the organs
what forms the quadrants of the abdomen
by transumbilical horizontal plane passing though umbilicus and IV disc bet L3-L4 intersecting the vertical median plane
what are the organs of the RUQ
right lobe of liver, gallbladder
distal stomach - pylorus, 1st 3 parts of duodenum, head of pancreas
R adrenal gland, R kidney,
R hepatic flexure of colon, sup ASCENDING colon, R transverse colon
what are the organs of LUQ
L lobe of liver, spleen and most of stomach
second and third portion of jejunum and proximal ileum
body and tail of pancreas, L adrenal gland and L kidney
L splenic flexure of colon, sup DESCENDING colon, L transverse colom
what are the organs of RLQ
cecum, appendix and most of ileum
inf ASCENDING colon
R ovary. R uterine tube, R ureter, R spermatic cord
what are the organs of LLQ
sigmoid colon, inf DESCENDING colon
L ovary, L uterine tube, L ureter, L spermatic cord
how are the regions of the abdomen formed
into 9 by:
2 longitudunal lines - R and L midclavicular
2 transverse planes - subcostal and intertubercular
right hypochondriac region
liver, galbladder
R kidney
ascending colon, transverse colon, small intestine
epigastric region
esophagus, liver, stomach, pancreas and spleen
R and L adrenal glands and R and L kidneys
transverse colon and small intestine
left hypochondriac region
liver, stomach, pancreas and spleen
L kidney
transverse and descending colon
right lumbar region
liver, galbladder
R kidney
ascending colon and small intestine
umbillical region
stomach and pancreas
R and L kidneys and ureters
transverse colon and small intestine
left lumbar region
L kidney
small intestine and descending colon
right iliac region
appendix
R ovary and fallopian tube
ascending colon, cecum, small intestine
hypogastric region
rectum, bladder and uterus
R and L ureters, ovaries, fallopian tubes
sigmoid colon
left iliac region
L ovary and fallopian tube
descending and sigmoid colon, small intestine
what does the transpyloric plane cross
costal margin on each side at 9th CC; L1
opening of stomach into duodenum on R or pyloric orifice
neck of pancreas
approx pos of the hila of kidneys
what does the transpyloric plane cross
pass through tips of 9th CC
what does the subcostal plane cross
lowest point of CC; L3
what does the intercristal plane cross
plane passing the highest point of iliac crest; L4
what does the intertubercular plane cross
line joining tubercles of iliac crest; L5
what are the functions of the anterior abdominal wall
firm but flexible boundary keeping abdominal viscera in cavity and maintain their anatomical position
protects abdominal viscera from injury
assists in forceful expiration, coughing, vomiting, defecation, peeing, giving birth; inc intraabdominal psi
what is the function of oblique muscles
oblique muscles laterally flex and rotate trunk
what is the function of pyramidalis
keeps linea alba taut
what is the function of rectus abdominis
flexes trunk and stabilize pelvis
what is the function of anterior and lateral muscles
assists diaphragm in relaxing para may space abdominal viscera
what are the 7 layers of the anterolateral abdominal wall
skin
superficial fascia
deep fascia
muscles
transversalis fascia
extraperitoneal fascia
parietal peritoneum
where is the skin attached
loosely attached to all underlying structures except at the umbilicus
what are lines of cleavage
natural lines of the skin that run downward and forward
horizontal around the trunk
what is the umbilicus
scar tissue representing the site of attachment if umbilical cord
what is the nerve supply of the skin of abdominal wall
from anterior rami of T7-T12 and L1
T7-T11 becomes the lower 5 intercostal nerves
T12 is subcostal nerve
L1 is iliohypogastric and ilioinguinal nerve
what are the dermatomes of the abdominal wall
T7 - epigastrium at xiphoif
T10 - umbilicus
L1 - above inguinal ligament and symphysis pubis
what is the arterial blood supply of the skin at midline of the abdominal wall
midline - from superior and inferior epigastric arteries
flanks - intercostal
what is the arterial blood supply of the skin at flanks of the abdominal wall
flanks - intercostal, lumbar and deep circumflex iliac
what is the arterial blood supply of the skin at inguinal region of the abdominal wall
superficial epigastric, sficial circumflex iliac and sficial external pudendal (from femoral)
what is the venous drainage of the skin of the abdominal wall
above umbilicus - lateral thoracic to axillary
below umbilicus - superficial epigastric and great saphenous to femoral vein
what is the composition of the superficial fascia above umbilicus
single sheet of CT continous w the superficial fascia in other regions of the body
what is the composition of the superficial fascia below umbilicus
divides into camper’s fascia (superficial fatty layer) and the scarpa’s fascia (membranous deep layer)
describe camper’s fascia
usually thick and thicker on obese patients
continous with sficial fat of the rest of body
becomes the dartos muscle (smooth muscle) scrotum
describe scarpa’s fascia
thinner and fades out laterally and becomes continous w sficial fascia of back and thorax
inferiorly fuese w deep fascia of thigh; 1 finger below inguinal ligament
becomes colle’s fascia in scrotum or labia majora
posteriorly fused to perineal body and becomes posterior margin of perineal membrane
describe the deep fascia
thin layer of CT covering the muscles
immediately deep to scarpa’s fascia
what are the 2 main groups of muscle in abdominal wall
flat (transverse) - laterally on each side of abdomen
vertical - near midline of boday
what are the flat muscles
external oblique
internal oblique
transversus abdominis
describe the aponeuroses of flat muscles
each flat muscles form an aponeurosis at anteromedial whoch covers rectus abdominis
they entwine at midline forming linea alba
what is the transversalis fascia
thin layer of fascia betw muscle layer - abdominal wall and parietal peritoneum
continous w fascia of pelvic wall
what is the femoral sheath
downward prolongation of transversalis and iliac fascial linings around the femoral vessels and lymphatics
what does the fascia transversalis do inferior to arcuate line
w parietal peritoneum it forms the posterior wall of rectus sheath
what does the fascia transversalis do at midpoint
spermatic fascia pierces it to form deep inguinal ring
also forms internal spermatic fascia from the margins of ring
what is the rectus sheath
long fibrous sheath that encloses rectus abdominis and pyramidalis
what forms the rectus sheath
aponeuroses of the 3 lateral abdominal muscles
what forms the walls of the rectus sheath above the costal margin
ant - formed by apon of external oblique
post - by 5-7 cc and intercostal space
what forms the rectus sheath betw the costal margin and arcuate line (ASIS)
aponeurosis of internal oblique splits to enclose the rectus muscle
external oblique aponeurosis is directed in front of the muscle
transversus aponeurosis is directed behind the muscle
what forms the rectus sheath betw the arcuate line (ASIS) and pubis
ant - apon of all 3 muscles
post - absent posy wall
rectus muscle is in contact w fascia transversalis
what is extraperitoneal fat
fat betw transversalis and parietal peritoneum
what is parietal peritoneum
serous membrane that forms the abdominal wall
what is the nerves of the anterior abdominal wall
lower 6 thoracic and 1st lumbar
phrenic - central part of diaphragmatic peritoneum
T12 - pyramidalis
L1 - ilioinguinal nerve enters inguinal ring to supply skin above inguinal ligament and symphysis pubis
what is the dermatomes of the anterior abdominal wall
T7 - xiphoid process
T10 - umbilicus
L1 - pubis
what are the arteries of anterior abdominal wall
superior epigastric
- terminal branch of internal thoracic
- supplies upper central part
inferior epigastric
- branch of external iliac
- lower central part
deep circumflex iliac
- lower lateral part
lower 2 posterior intercostal arteries and 4 lumbar
- lateral part
what is the inguinal canal
oblique passage through lower part of anterior abdomen; both sexes
where does the inguinal canal start and end
deep inguinal ring to superficial inguinal ring
compare the inguinal canal in male and female
male - structures to pass to and from testis from abdomen
female - passage of round ligament from uterus to labium majus
what is the anterior wall of inguinal canal
Anterior wall: Aponeurosis of external oblique muscle, reinforced by internal oblique from inguinal ligament
what is the posterior wall of inguinal canal
Posterior wall: conjoint tendon
what is the inferior wall of inguinal canal
formed by rolled inferior edge of aponeurosis of the external oblique
what is the superior wall of inguinal canal
formed by arching lowest fibers of the internal oblique and transversus abdominis
what is the deep inguinal ring
oval opening in fascia transversalis above the inguinal ligament
what is the purpose of the deep inguinal ring
Allow structures of spermatic cord to pass to and from the testes to abdomen
Transmit ilioinguinal nerve
what is the superficial inguinal ligament
triangular in shape from external oblique
what makes up the spermatic cord
● Vas deferens
● Testicular artery and vein
● Testicular lymph vessels
● Autonomic nerves
● Processus vaginalis
● Cremasteric artery
● Artery of vas deferens
● Genital branch of genitofemoral nerve
what is the vas deferens
● Cordlike structure at the posterior spermatic cord
● Transports spermatozoa from epididymis to urethra
what foes the testicular artery do
(from abdominal aorta)
● Branch from the abdominal aorta at the level of L2
● Supplies testes and epididymis
what does the testicular veins do
● Pampiniform plexus at the posterior of the testis leaves and becomes a single vein at the deep inguinal ring
● Drains to left renal vein on the left and into the inferior vena cava on the right
what are the covering of the spermatic cord
External spermatic fascia (from external oblique aponeurosis)
Cremasteric fascia (from internal oblique muscle)
Internal spermatic fascia (from fascia transversalis)
what is the scrotum
● Outpouching of the lower anterior abdominal wall
what are the contents of the scrotum
● Testes
● Epididymides
● Lower ends of spermatic cord
compare the layers of abdominal wall to scrotum
Abdominal wall
● Skin
● Camper’s fascia
● External oblique fascia
● Internal oblique muscle
● Transversalis fascia
Scrotum
● Skin
● Dartos muscle
● External spermatic fascia
● Cremasteric fascia
● Internal spermatic fascia
what is the lymph of scrotum
ascends to inguinal canal to reach lumbar nodes at L1
what is the testis
● Firm mobile organ within the scrotum
● Left testis is usually lower than right
● Tunica albuginea
- Tough fibrous capsule of testes
what is the epididymis
● Posterior to the testis
● Part: head, body and tail
what are the functions of the epididymis
● Provides storage for spermatozoa and allows them to mature
● For absorption of fluid
● Contains substance added to the seminal fluid to provide nourishment for the maturing sperm
what is the labia major
● Prominent hair bearing folds of skin formed by enlargement of genital swellings fetus
● Contains adipose and terminals stands of the round ligaments of the uterus
what are the bones of the posterior abdominal wall
lumbar vertebrae
12th pair of ribs
ilium
what are the muscles of PAW
● Psoas major
● Quadratus lumborum
● Transversus abdominis
● Iliacus
● Posterior part of diaphragm
how does a hernia develop
develops when the outer layers of the abdominal wall are weak, allowing the inner lining of the abdomen to push through
intestine or abdominal tissue slips causing it to bulge out or protrude beneath the skin
what is indirect hernia
most common and congenital
most common in males; children and young adults
right side usually more affected
neck of hernia is narrow
what direct hernia
common in old men bc of weak abs
common in male
neck of hernia is wide
what is femoral hernia
common in females
neck lies at femoral ring
inguinal hernia
common in male
spigelian hernia
● Hernia of linea semilunaris usually below the umbilicus
umbilical hernia
● Congenital or acquired
often in pediatric
paraumbilical hernia in adults - more common in women
what is omphalocele
congenital umbilical hernia
caused by failure of midgut to return to abdominal cavity; nasa labas yung organs
lumbar hernia
Occurs through the lumbar triangle (petit’s triangle), a weak area in posterior abdomen
● Neck of the hernia is large and incidence of strangulation is low
describe acquired umbilical hernia
Acquired infantile is small hernia caused by weakness of the scar the umbilicus at linea alba
That is why we don’t want to tug on the umbilical cord during delivery, you have to cut it and maintain the integrity of this cord in the abdominal wall until it dries and falls off
what are the boundaries of petit’s triangle
● Anteriorly by posterior margin of external oblique muscle
● Posteriorly by the anterior border of latissimus dorsi
● Inferiorly by iliac crest
what is diastasis recti
occus in elderly multiparous women
bc excessive stretch of rectus sheath aggravated by coughing and straining
how to treat diastasis recti
abdominal belt
exercise
what determines the type of abdominal incision
- Position and direction of the nerve and the abdominal wall
- Direction of the muscle fiber
- Arrangement of the aponeurosis forming the rectus sheath
- Direction of the line of cleavage
paramedian
for maximal exposure for what we want to see inside
Pfannenstiel
bikini cut/area, for c-section
pararectus
Anterior wall of rectus sheath is incised medially and parallel to the lateral of the rectus muscle
● Disadvantage: the opening is small and any longitudinal extension require one or more segmental nerves of the rectus abdominis to be divided, rectus muscle weakness
midline incision
Made through the linea alba
● Rapid method in gaining entrance to the abdomen
● Does not damage muscle, its nerve and blood supply
structures penetrated in midline incision
● Skin
● Camper’s
● Scarpa’s
● Deep fascia
● Linea alba
● Fascia transversalis
● Extraperitoneal fat
● Parietal peritoneum
transrectus
through the rectus abdominis muscle longitudinally
● Has a disadvantage of sectioning the nerve supply to the part of the muscle
transverse
Above or below the umbilicus that can extend from flank to flank
● Is rare to damage more than one segmental nerve thus post op weakness of the muscle is minimal
● Gives good exposure and is well tolerated
mcburney’s
Used for cecostomey or appendectomy
● Gives limited exposure only
● Oblique incision made in the right iliac region 2 inches above and medial to the ASIS (or ⅔ from umbilicus)
layers in mcburney
● Skin
● Superficial fascia (camper’s and scarpa’s)
● Deep fascia
● External oblique muscle
● Internal oblique muscle
● Transversus abdominis
● Transveralsis fascia
● Peritoneum
ASW layers lateral to rectus sheath
● Skin
● Fatty layer
● Membranous layer
● Deep fascia
● External oblique muscle or aponeurosis
● Internal oblique muscle or aponeurosis
● Transversus abdominis muscle or aponeurosis
● Fascia transversalis
● Extraperitoneal connective tissue (fat)
● Peritoneum
ASW layers at midline
● Skin
● Fatty layer
● Membranous layer
● Deep fascia
● Linea alba
● Fascia transversalis
● Extraperitoneal connective tissue
● Parietal peritoneum
ASW layers anterior to rectus sheath
● Skin
● Fatty layer
● Membranous layer
● Deep fascia
● Anterior wall of rectus sheath
● Rectus muscle
● Posterior wall of rectus sheath
● Transveralsis fascia
● Extraperitoneal fat
● Parietal peritoneum
