Abdominal Wall Flashcards
What are the contents of the Abdominal region?
peritoneal cavity; gastrointestinal tract and associated glands and digestive organs; nerves; lymphatic; blood vessels; renal system
What are the bony landmarks of the anterior abdominal wall?
xiphoid process; costal margins; ilium; pubis
What is the linea terminalis?
a line that separates the true pelvis from the false pelvis
What is superior to the linea terminalis?
abdomen or false pelivs
What is inferior to the linea terminalis?
pelvis or true pelvis
What is the pelvic inlet formed by?
pectin pubis (pubic bone), arcuate line (ilium), sacral promontory (sacrum)
Name the layers of the abdomen (superficial -> deep)
skin; fatty layer (camper’s); membranous layer (scarpa’s)
What is camper’s continuous with?
the superficial fatty layers in the thorax, thigh and perineum
What is scarpa’s continuous with?
fascia lata in the thigh and with the deep layer of superficial perineal fascia
True or false?
Scarpa’s fuses with the fascia kata and is continuous over the penis and scrotum
true
True or false?
Deep fascia follows the same pattern as the membranous layer of superficial fascia
false, does not follow the same pattern
True or false?
Fluid can leak into the potential space between the membranous layer of superficial fascia and the deep fascia of the external abdominal oblique muscle
true
Describe the transpyloric plane of the abdomen
transverse plane midway between the superior borders of the pubic symphysis and the manubrium
Describe the subcostal plane of the abdomen
plane at the lowest level of the costal margin
Describe the supracrestal plane of the abdomen
plane passing through the summits of the iliac crests
Describe the transtubercular plane of the abdomen
plane at the level of the iliac tubercles
Describe the interspinous plane of the abdomen
plane at the level of the anterior superior iliac spine
How many regions are in the anterior & lateral abdominal wall
9
What are the four pairs of muscles, located anteriorly and laterally collectively that compress and hold the abdominal organs in place
external obliques, internal obliques, transversus abdominis, rectus abdominis
What do the four pairs of muscles in the abdominal wall work together to do?
flex and stabilize the vertebral column; when they unilaterally contract they flex the vertebral column
What are the four pairs of muscles located posteriorly in the abdomen that flex the spine and lower limb?
iliacus, psoas major, psoas minor, quadratus lumborum
The three “flat muscles of the anterior/lateral abdominal wall end anteriorly in a strong sheet of aponeurosis called what?
the rectus sheath
What does the rectus sheath enclose?
rectus abdominis
What is the midline of the recuts sheath called?
linea alba
The layers of fascia and aponeuroses of the muscles forming the rectus sheath are arranged differently in the upper abdominal wall than they are in the lower wall. The line where this arrangement changes is located about 1/2 way between umbilicus and pubic symphysis and is called what?
the arcuate line
What are the muscles above the arcuate line?
the aponeurosis from the internal oblique splits to surround rectus abdomens and the aponeurosis from transverses abdomens runs posterior to rectus abdominis
What are the muscles below the arcuate line?
the rectus abdominis muscle lies directly on transversals fascia
What are the muscles of the abdominal wall: anterior & lateral?
rectus abdominis, external obliques, internal obliques, transversus abdominis
List the 4 abdominal wall muscles from superficial to deep order
external obliques, internal obliques, rectus abdominus, transversus abdominus
What is the action of the external oblique muscle?
bilateral action: flexes vertebral column and compresses abdominal wall
unilateral action: lateral flexion of vertebral column
What is the action of the internal oblique and what is it innervated by?
bilateral action: flexes vertebral column and compresses abdominal wall
unilateral action: lateral flexion of vertebral column
What is the action of the transversus abdominis?
bilateral action: flexes vertebral column, compresses abdominal wall, unilateral action: lateral flexion of vertebral column
What is the action of the rectus abdominis?
flexes vertebral column: compresses abdominal wall
What are the four posterior abdominal wall muscles? And what is their primary function?
Iliacus, psoas major, psoas minor, quadratus lumborum
function: flexors of the trunk and/or hip
Where does the deep system of anterior abdominal wall arteries originate from?
originate superiorly from the subclavian artery
branches in the mid-abdomen are from the abdominal aorta
originate inferiorly from the external iliac artery
Where does the superficial system of anterior abdominal wall arteries originate from?
originate superiorly from perforating branches
originate inferiorly from branches of the femoral artery
What are the deep arteries of the anterior abdominal wall?
musculophrenic anteriror artery; superior epigastric artery; inferior epigastric artery; intercostal anterior artery; subcostal anterior artery; lumbar anterior artery; deep circumflex iliac anterior artery
What are the superficial arteries in the anterior abdominal wall?
superficial circumflex iliac artery; superficial epigastric artery; external pudendal artery
What are the deep veins of the anterior abdominal wall?
subclavian vein, external iliac vein, lumbar & intercostal veins
What are the superficial veins of the anterior abdominal wall?
thoracoepigastric vein; lateral thoracic vein; superficial epigastric vein
What are the nerves in the anterior abdominal wall?
sensory dermatomes: T7-L1
True or False?
anterior abdominal wall nerves are cutaneous branches of ventral rami
true
What do anterior abdominal wall nerves lie between?
internal abdominal oblique and transverus abdominis
What do anterior abdominal wall nerves pierce?
the rectus sheath to innervate the rectus abdominis muscles
What do anterior abdominal wall nerves supply?
skin, muscles and parietal peritoneum
The iliohypogastric nerve (L1) supplies what region?
suprapubic
The ilioinguinal nerve (L1) enters the inguinal canal and emerges through the superficial inguinal ring and supplies what?
groin and scrotum/labium majus
The genitofemoral nerve (L1 and L2) has two branches. Name the branches and the area they supply
genital branch: innervates the cremaster muscle or is cutaneous to the labium majus
femoral branch: cutaneous to the femoral triangle area
Where do superior lymphatics in the anterior abdominal wall drain?
superiorly form umbilical region to anterior axillary and sternal nodes
inferiorly from umbilical region to superficial inguinal nodes
Where do deep lymphatics in the anterior abdominal wall drain?
along posterior intercostal and lumbar vessels to deep abdominal nodes
from testes to deep abdominal nodes
What is a hernia?
when a portion of the viscera protrudes through a weakened point of the muscular wall of the abdominopelvic cavity
When does a strangulated intestinal hernia occur?
when blood flow to the trapped segment diminishes, causing that portion of the intestine to die
What are the two types of hernias?
inguinal and femoral
Which type of hernia is most common?
inguinal
True or False?
The inguinal region is one of the strongest areas of the abdominal wall
false; weakest
What causes an inguinal hernia?
rising pressure in the abdominal cavity provides the force to push a segment of the small intestine into the canal
Explain what occurs in a direct inguinal hernia
the loop of the small intestine protrudes directly through the superficial inguinal ring, but not down the entire length of the inguinal canal, and creates a bulge in the lower anterior abdominal wall
Explain what occurs in an indirect inguinal hernia
herniation travels down the entire inguinal canal and may event extend all the way into the scrotum
Where does a femoral hernia occur?
occurs in the upper thigh, just inferior to the inguinal ligament, originating in the femoral triangle
True or false?
women more commonly develop femoral hernias because of the greater width of their femoral triangle
true
When does an umbilical hernia occur?
when a portion of intestine pushes through abdominal wall musculature in the periumbilical or umbilical region
note: most common in infants