Abdominal Wall Flashcards
Layers of the abdominal wall
skin
Camper’s fascia (fatty)
Scarpa’s fascia (membranous)
muscles/associate fascia (ext/int/TA)
transversalis/extraperitonal fascia
parietal peritoneum
Significance of the umbilicus
scar along linea alba, site of attachment for umbilical cord
superficial fascia of the abdomen
layer of fatty connective tissue continuous with other bodily fasica
splits into two layers at the umbilicus level
fatty Camper’s and membranous Scarpa’s, Camper’s most superficial
Abdominal fascia in men vs women
men: continues to penis, layers fuse and lose fat going into the scrotum to form a fascia layer with smooth muscle fibers (dartos fascia)
women: layers retain some fat and go into labia majora
Scarpa’s fascia: properties and attachments
thin/membranous
no fat
deep to Camper’s
continues into thigh and fuses with fascia lata
attaches to linea alba and pubic symphysis
anterolateral muscles of the abdomen (5)
internal oblique
external oblique
transverse abdominus
rectus abdominus
pyramidalis
all form aponeurosis medially and attach at linea alba
transversalis fascia
deepest layer of abdominal wall before extraperitoneal fascia
extraperitoneal fascia
deepest layer of abdominal wall
deep to transversalis fascia
Where are the thoracoabdominal nerves found? What levels are they?
Below Ext and int obliques and above TA
T7-T11
external oblique
origin: outer surface 5th-12th ribs
insertion: linea alba, pubic crest, ASIS, iliac crest
innervation: anterior rami T7-12 and L1
action: rotate trunk contralaterally, compress abdominal contents
internal oblique
origin:thoracolumbar fascia, iliac crest, inguinal ligament
insertion: lower margins 9-12th ribs, pubic crest, linea alba
innervation: anterior rami T7-T12
action: ipsilateral trunk rotation, compress abdominal contents
transversus abdominus
origin: thoracolumnbar fascia, iliac crest, inguinal ligament, costal cartilage lower ribs
insertion: linea alba, pubic crest, pectineal line
innervation: anterior rami T7-12, L1
action: compress abdominal contents
rectus abdominus
origin: pubic crest, tubercle, and symphysis
insertion: costal cartilages of ribs 5-7 and xiphoid process
innervation: anterior rami T7-12
action: flex vertebral column, compress abdominal wall
pyramidalis
origin: front of pubis and pubic symphysis
insertion: linea alba
innervation: anterior ramus T12
action: tenses linea alba
What forms the rectus sheath?
aponeuroses of ext/int oblique and TA muscles
tendons of flat muscles
What does the rectus sheath encompass?
rectus abdominus and pyramidalis
significance of the arcuate line
above arcuate line: aponeuroses of ext oblique over rectus, int oblique surrounds, TA below
below arcuate line: all aponeuroses go above rectus abdominus
What forms the inguinal ligament?
aponeurosis of external oblique, most superficial layer
lacunar and pectineal ligaments
lacunar ligament connects the inguinal ligament to the pectineal ligament which attaches to the pectineal line of the pubis
inguinal ligament path
formed by ext oblique aponeurosis
pass between ASIS and pubic tubercle
lacunar ligament
extension of fibers at the medial end of the inguinal ligament
attach to pectin pubis on superior ramus of pubic bone
pectineal ligament
extension of lacunar ligament along pectineal pubic line
inguinal canal
above and parallel to inguinal ligament
deep inguinal ring to superficial inguinal ring
present in both sexes
not equivalent to femoral triangle
deep inguinal ring formed by what fascia?
transversalis fascia
contents of inguinal canal
men: spermatic cord
women: round ligament of the uterus
spermatic cord structures include:
ductus deferens artery
testicular artery/veins
sympathetic/afferent nerves
lymphatics
round ligament of the uterus
cord structure passing through inguinal canal
passes from uterus to deep inguinal ring, superficial ring, then attaches to connective tissue of labia majora
functions to maintain anteflexion position of uterus, turning fundus of the uterus towards cervix junction
direct inguinal herbia
peritoneum passes through abdominal wall/posterior wall of the inguinal canal due to weak muscle/aponeurosis and presses through superficial ring
indirect inguinal hernia
peritoneum passes through the deep ring to the inguinal canal
Vessels present in the anterolateral abdominal wall
internal thoracic artery branches: intercostal, musculophrenic, and superior epigastric aa.
femoral artery branch: superficial circumflex iliac a.
external iliac branches: inferior epigastric and deep circumflex iliac aa.
