Abdominal Wall Structure Flashcards
What are the superior and inferior borders of the abdominal wall?
Superior - xiphoid process, costal cartilages ribs 7-10
Inferior - Iliac crest, Inguinal ligament, Pubic bone
What spinal nerve innervates the skin around the umbilicus?
T10
What are the linea alba, semilunares, and transversae?
Linea alba - linear endinous raphe extending along the midline; medial border of two rectus abdominis muscles
Linea semilunares - Connective tissue along alteral borders of rectus abdominis
Linea transversai - fibrous connective tissue bands within rectus abdominis muscles
What planes divide the abdomen into regions?
Two longitudinal - right and left midclavicular
Two horizontal - subcostal plane and transturbercular plane
What is McBurney’s point?
One-third of the way up a line between right anterior superior iliac spine and umbilicus
Point of maximum tenderness during acute appendicitis
What surface region does acute diverticulitis refer to?
Left lower quadrant
What surface region does acute pancreatitis refer to?
Epigastric
What surface region does acute cholecystitis refer to?
Right hypochondrial
What are the layers of Anterior Abdominal Wall superficial to deep??
Skin
Superficial Fascia (Fatty/Campers -> Membrane/Scarpa’s)
Deep fascia covering muscles
Transversalis fascia (endoabdominal)
Extraperitoneal fat
Parietal Peritoneum
What is camper’s fascia?
Fatty layer of superficial fascia
Contains superficial epigastric vessels
Continues as superficial fascia of thigh
What is Scarpa’s fascia?
Membranous layer of superficial fascia
Fused with deep fascia of thigh (fascia lata)
What is the difference between the midline and lateral approach to penetrating the abdominal wall?
Midline - pass through the linea alba after the superficial fascia
Lateral - pass through muscles layers after the superficial fascia
What is the rectus sheath?
Incomplete connective tissue envelope that surrounds each rectus abdominis muscle; formed by aponeuroses of the anterolateral muscles
What does the rectus sheath contain?
Rectus abdominis and pyramidalis muscles
Superior and inferior epigastric vessels
Terminal ends of T7-12 nerves
What is the arcuate line?
Marks the change in fascia contributing to the anterior and posterior layers of the rectus sheath; occurs below umbilicus at a point midway between umbilicus and pubis
What is the difference between the area superior to the arcuate line and inferior to the arcuate line?
Superior -rectus abdominis is completely enclosed by aponeuroses of the anterolateral abdominal wall muscles
Inferior - the aponeuroses of all three muscles pass anterior to the rectus abdominis muscle
Describe the innervation to muscles and skin of the anterior abdominal wall
T7-L1
Thoracoabdominal nerves (T7-T11)
Subcostal nerve (T12)
Iliohypogastric nerve (L1)
Ilioinguinal nerve (L1)
What are the four major vessels that provide blood supply to the abdomen?
Internal thoracic - superior epigastric/musculophrenic
Aorta - posterior intercostal/subcostal
External Iliac - inferior epigastric (can also give rise to obturator and deep circumflex iliac
Femoral Artery - Superficial epigastric/superficial circumflex iliac
What arteries anastomose within the rectus sheath?
Superior epigastric and Inferior epigastric
Form major connection between subclavian and external iliac
Important if aorta becomes obstructed
What are the umbilical folds?
Coverings of the peritoneum on the ifnerior half of the abdominal wall taht cours toward the umbilicus
Five total: One along the midline and two on either side (medial and lateral folds)
What are the peritoneal fossa?
Depressions lateral to the umbilical folds which are potential sites for hernias
What is Caput Medusae?
Condition in which veins of anterior abdominal wall are swollen and dilated due to blockage
Can be caused by cirrhosis of the liver, chronic hepatitis, or portal hypertension
What is aortic coarctation?
Narrowing of the aorta that can occur at the site of the ductus arteriosus
Collateral circulation is provided by the superior and inferior epigastric arteries
What are the three parts of a hernia?
The sac
Contents of the sac
Coveriong of the sac
What is an umbilical hernia?
Herniation of intestinal loops through the umbilical rings
Common in newborns
What are congenital umbilical hernias?
Have an embryological basis and are present at birth
What is an acquired infantile hernia?
Small hernia that often occurs in infants and children, occurs through defect in linea alba and protrudes during crying, straining or coughing
Usually resolves by 3-5 w/o treatment
What is an acqured adult umbilical hernias?
Called a paraumbilical hernia when the hernia sac does not protrude through the umbilical scar, but instead through the linea alba in the region of the umbilicus
What is an epigastric hernia?
Occurs through linea alba above umbilicus in the epigastric region
What is a spigelian hernia?
Occurs along the linea semilunares
Occurs at or below the arcuate line where the rectus abdominis is in direct contact with the transveralis fascia
