Anterior Abdominal Wall Flashcards
pelvic inlet
- this the line that separates the true pelvis from the false pelvis
- formed from the:
- pectin pubis
- arcuate line
- sacral promontory
differentiate the true pelvis from the false pelvis
- true pelvis is inferior to the pelvic inlet or linea terminalis
- false pelvis is superior to the linea terminalis
linea semilunaris
lateral border of the rectus abdomens muscle
linea alba
- vertical midline through the navel
- gives rise to suspensory ligaments of the penis and suspensory ligaments of the clitoris
umbilicus
navel
subcostal plane
- horizontal
- 10th costal cartilage
- superior border at LV3
transtubercular plane
- horizontal
- tubercles of the iliac crests
- body of LV5
transumbilical plane
-horizontal
-LV3-4
similar to the supracristal plane
transpyloric plane
- horizontal
- T12-LV1
- halfway b/w the jugular notch and the pubic symphysis
- goes thru the pyloric part of the stomach which is “fixed”
midclavicular plane
- vertical
- midpoint of clavicle
- midinguinal point
midsagittal plane
- vertical
- median line
- linea alba
- passes thru umbilicus
contents of right upper quadrant
- gallbladder
- duodenum
- right pleura (of lungs)
- liver (right lobe)
- right kidney
contents of left upper quadrant
- spleen
- stomach
- left pleura (of lungs)
- tail of pancreas
- left kidney
contents of right lower quadrant
- right ureter
- cecum
- ilial diverticulum–not all ppl have this
- vermiform appendix
contents of left lower quadrant
- left ureter
- descending and sigmoid colon
identify the regions of the abdomen
a. R hypochondriac (7)
b. L hypochondriac (4)
c. Epigastric (1)
d. R lumbar (lateral) (8)
e. L lumbar (lateral) (5)
f. Umbilical (2)
g. R inguinal (iliac) (9)
h. L inguinal (iliac) (6)
i. Hypogastric (pubic) (3)
anterior abdominal muscles
-rectus abdominis and sometime pyramidalis
anterolateral abdominal muscles
- external abdominal oblique
- internal abdominal oblique
- transversus abdominis
posterior abdominal muscles
- iliacus
- psoas major and minor
- quadratus lumborum
McBurney’s Point
1/3 of the distance from the lateral end of a line b/w the umbilicus and the ASIS
external abdominal oblique
- fibers inferiomedially
- wide aponeurosis which begins at midclavicular lines
- aponeurosis meets at midline to join aponeurosis of other side and form the linea alba
- inguinal ligament is the specialized part of the lower free margin of the aponeurosis
- ext. oblique M attaches to the ASIS and then folds over and creates a sling which a round ligament or spermatic cord sits
- FUNC: unilaterally bend and twist toward midline
superficial inguinal ring
triangular opening in the aponeurosis b/w the pubic tubercle and pubic symphysis
-made up of he medial crus, lateral crus, and intercrural fibers
lacunar ligament
- extension of the inguinal ligament that is triangular in shape
- found at the apex of the pubic tubercle
- base is concave, lateral, and sharp
- important with femoral hernias b/c this sharp edge can cuts thru the bowel that descends down into the canal and cause ischemia
pectineal ligament
- lateral posterior extension of the lacunar ligament that runs along the pectineal line
- can also form a sharp border that can constrict a femoral hernia
internal abdominal oblique
a. broad aponeurosis
i. fibers run superomedially and horizontally to join the muscle from the opposite side
b. usually perpendicular to the external oblique fibers
c. cremaster muscle is from the internal oblique layer
d. helps to form the conjoint tendon or fall inguinalis
e. FCN: lateral bend and twist toward ilium
cremaster muscle
- from the internal oblique layer
- this is the muscle surrounding the spermatic cord
transversus abdominis M
a. innermost of the 3 layers
b. wide aponeurosis begins at linea semilunaris
c. fibers run horizontally
d. medially it forms the conjoint tendon with the internal oblique
e. used in contracting or girdling of the abdomen (defamation)
where are nerves and vessels found?
-b/w the internal abdominal oblique and transverses abdominis
rectus abdominis M
a. strap muscles (pair)
b. broad, superiorly, narrow inferiorly
c. tendinous intersections
i. perpendicular to fibers
d. enclosed by rectus sheath
e. FCN: maintain stability, flexor, brings thoracic cage closer to thighs
pyramidalis M
a. often missing in 8-10% of the population
b. also in the rectus sheath
c. attaches to pubic crest
d. tenses the linea alba
functions of the anterior abdominal wall muscles
i. flex trunk (anteriorly)
ii. laterally flex the trunk
iii. rotate the trunk
iv. assist in respiration
v. important in Valsalva maneuver
vi. also act during coughing, sneezing, urination, defacation, vomiting, parturition
Camper’s fascia
- most superficial of superficial fascia
1. fatty layer, more superficial
a. Continuous with the superficial fatty layers in the thorac, thigh, perineum
b. Superficial blood vessels run in the fatty layer here
Scarpa’s fascia
- membranous layer, deeper (still superficial fascia)
a. Continuous with the fascia lata in the thigh and with the deep perineal fascia
b. Does not have the adipose tissue that is in Camper’s
c. continuous over the penis and the scrotum
i. Creates the septum in the scrotum and makes Buck’s fascia that goes around the penis itself
1. No fatty Camper’s layer in the penis or scrotum
deep fascia
i. Invests the muscles
ii. Does not follow the same patter as the membranous layer of the superficial fascia
iii. Clinically important b/c holds sutures
iv. potential space is found b/w this and superficial fascia
potential space
i. b/w the membranous layer of the superficial fascia (Scarpa’s) and the deep fascia of the external abdominal oblique M
1. fluid can leak into this potential space b/w the membranous layer of the superficial fascia and the deep fascia of the external abdominal oblique muscle
rectus sheath
i. formed by the fusion of the abdominal muscles and their associated fascias
1. includes the external/internal obliques and transversus abdominis
ii. encloses the rectus abdominis and the pyramidal M
iii. layers of fascia and aponeuroses of the muscles forming the rectus sheath are arranged differently in the upper abdominal wall than the lower wall
1. arcuate line is where the change in arrangement occurs
rectus sheath above the arcuate line
- anterior:
a. skin
b. fatty layer of superficial fascia
c. membranous layer of superficial fascia
d. aponeuorisis of external abdominal oblique fascia (2 layers)
e. 1 layer of internal abdominal oblique aponeurosis
f. rectus abdominis muscle - posterior:
a. 1 layer of internal abdominal oblique aponeurosis
b. aponeurosis of transversus abdominis (2 layers)
c. transversalis fascia
d. extraperitoneal tissue
e. parietal peritoneum
rectus sheath below arcuate line
- anterior:
a. skin
b. fatty layer of superficial fascia
c. membranous layer of superficial fascia
d. aponeurosis of external abdominal oblique (2 layers)
e. aponeurosis of internal abdominal oblique (2 layers)
f. aponeurosis of transversus abdominis (2 layers)
g. rectus abdominis M - posterior:
a. transversalis fascia
b. extraperitoneal tissue
c. parietal peritoneum
deep system of abdominal As.
i. originate superiorly from the subclavian artery
1. via the internal thoracic A
ii. branches in the midabdomen from the abdominal aorta
iii. originate inferiorly from the external iliac A
superficial system of abdominal As.
i. originate superiorly from perforating branches
ii. originate inferiorly from branches of femoral A
iii. coming off of femoral A and just in inguinal region
what are the arteries involved in the deep system of arteries?
- musculophrenic A
- superior epigastric A
- inferior epigastric A
- intercostal A
- subcostal A
- lumbar A
- deep circumflex iliac A
- inferior epigastric A
direct inguinal hernia
hernia that is medial to the inferior epigastric A
indirect inguinal hernia
hernia that is lateral to the inferior epigastric A
what are the arteries involved in the superficial system of arteries?
-superficial circumflex iliac A
-superficial epigastric A
-external pudendal A
(superficial and deep branch)
DEEP anterior abdominal wall veins
i. within abdominal wall Ms along with arteries
ii. to subclavian V
iii. to external iliac V
iv. to lumbar and intercostal Vs
SUPERFICIAL anterior abdominal wall veins
i. within Camper’s fascia
ii. throacoepigastric V
iii. lateral thoracic V
iv. superficial epigastric V
thoracoabdominal intercostal Ns.
i. lateral cutaneous branches emerge anterior axillary region
1. bifurcates into anterior and posterior branches
ii. anterior cutaneous branches end with medial and lateral branches
sensory dermatomes of the anterior abdominal wall
i. T7: xiphoid region
ii. T10: umbilical region
iii. L1: inguinal fold region
intercostal N
T7-11
subcostal N
T12
lumbar N
L1-4
anterior abdominal wall nerves
- lie b/w internal abdominal oblique and transversus abdominis
- pierce rectus sheath to innervate rectus abdomens
- supply skin, muscles, and parietal peritoneum
- angle inferiomedially
iliohypogastric N
L1 and sometimes T12
- exits the posterior abdominal wall b/w quadratus lumborum and psoas muscle
- enters the anterolateral abdominal muscles b/w the internal abdominal oblique and transverses abdominis
- supplies suprapubic region
ilioinguinal N
L1
- Exits posterior abdominal wall b/w quadratus lumborum and psoas M
- Enters anterolateral abdominal wall b/w internal oblique and transversus abdominis
- Enters inguinal canal and emerges thru the superficial inguinal ring
- Supplies groin, thigh, and scrotum/labium majus
genitofemoral N
L1 and L2
- break off into femoral area and genital area
- Exits posterior abdominal wall thru psoas M and runs b/w the peritoneum and psoas M
genital branch of genitofemoral N
a. Enters inguinal canal thru the deep inguinal ring and exits the inguinal canal thru superficial inguinal ring
b. Innervates cremaster muscle or is cutaneous to labium majus
femoral branch of genitofemoral N
a. Exits inferior to the inguinal ligament
b. Cutaneous to the femoral triangle area
superficial lymphatic drainage of the anterior abdominal wall lymphatics
i. drains superiorly from umbilical region to anterior axillary and sternal nodes
ii. drains inferiorly from umbilical region to superficial inguinal nodes
deep lymphatic drainage of the anterior abdominal wall lymphatics
i. along posterior intercostal and lumbar vessels to deep abdominal nodes
ii. from testes to deep abdominal nodes
umbilical hernia in infants
- Involve the umbilicus
- Scar of umbilicus did not heal properly
- Usually small and wider transversely
- Usually heal spontaneously
umbilical hernia in adults
- Result from weakened abdominal wall around umbilicus
- Usually superior to umbilical scar
- More common in women
- Require surgical repair
epigastric hernia
- hernia of linea alba
i. Does not involve umbilicus
ii. Protrudes thru the linea alba
iii. Usually are superior to the umbilicus
iv. More common in men
v. Repaired surgically if large or symptomatic
boundaries of the inguinal canal
i. Floor: inguinal ligament and lacunar ligament
ii. Roof: internal abdominal oblique fibers
iii. Anterior wall: external abdominal oblique
iv. Posterior wall: transversalis fascia and conjoint tendon
where does the inguinal canal start and end?
starts at the deep inguinal ring (about midpoint of the inguinal ligament) and ends at the superficial inguinal ring
direct inguinal hernia
a. Neck of the hernia sac is medial to the inferior epigastric A
b. Pushes DIRECTLY thru the anterior abdominal wall thru a weak inguinal triangle
c. Usually due to a weak conjoint tendon
d. More often bilateral than indirect hernia
e. More common in older males
f. Bulge usually thru hesselbach’s triangle
indirect inguinal hernia
a. Neck of hernia sac lies lateral to inferior epigastric A
b. Pushes thru the deep inguinal ring thru the canal and exits the superficial inguinal ring
c. Common in young males
d. Often due to incomplete closure of processus vaginalis
e. Most inguinal hernias are this type
femoral hernia
i. Exit the abdomen thru the femoral canal—INFERIOR TO THE INGUINAL LIGAMENT
ii. More common in women than men
spermatic cord–what is it made up of and where does it lie?
- ductus deferens, testicular A and V
- enters deep inguinal ring to get to inguinal canal
- exits superficial inguinal ring to leave inguinal canal
what is found in the male inguinal canal?
- ductus deferens
- testicular A
- pampiniform plexus of V
- ilioinguinal N
- genital branch of genitofemoral N
what is found in the female inguinal canal?
- round ligament of the uterus
- ilioinguinal N
- genital branch of genitofemoral N
describe the descent of the testes
- testes develop retroperitoneally from the urogenital ridge of the mesoderm in upper lumbar
- attached to gubernaculum which is attached to labioscrotal folds and will guide migration down
- eventually becoming the scrotal ligament
- at 7th month, testes reach the inguinal canal and a piece of peritoneum is formed called processus vaginalis
- this is pushed with the testes until it becomes tunica vaginalis
- testes go thru canal and pull layers of anterior abdominal muscles with them
- gubernaculum shortens and pulls testes into scrotum
- testes are now in scrotum and have pulled epididymus, ductus deferens, testicular vessels, nerves, and lymphatics from abdomen
where does internal spermatic fascia come from?
internal abdominal oblique
where does cremaster M and fascia come from?
internal abdominal oblique and Scara’s
where does external spermatic fascia come from?
external abdominal oblique
which layer is lost in the testes/scrotum descent?
transversus abdominis
descent of the ovaries
- primitive ovaries also attach to gubernaculum which is in labioscrotal fold
- develops into ovarian ligament and round ligament of the uterus
