5) Surgical Anatomy of Abdomen Flashcards
What are the superior and inferior boundaries of the anterior abdominal wall?
Superiorly - cartilage of ribs 7-10 and xiphoid process
Inferiorly - iliac and pubic crests
What muscles make up the anterior abdominal wall?
External oblique, internal oblique, transversus abdominis and rectus abdominis
What is the function of the 3 flat muscles?
Act to flex, laterally flex and rotate the trunk. Their fibres run in differing directions - strengthening the abdominal wall and decreasing the risk of herniation.
What is the most superficial flat muscle and in which direction do its fibres run?
External oblique, inferomedial fibres
What is the middle flat muscle and in which direction do its fibres run?
Internal oblique, superomedial fibres
What is the deepest flat muscle and in which direction do its fibres run?
Transversus abdominis, horizontal fibres
What does the linea alba form from and where does it run?
Fusion of aponeuroses of all flat muscles in midline
Runs from xiphoid process to pubic symphysis
Describe the rectus abdominis:
Has tendinous intersections to make muscle more efficient
Lines semilunaris mark lateral border of muscle
What is the rectus sheath formed from?
Formed by the aponeuroses of the three flat muscles and encloses the rectus abdominus
What forms the anterior wall of the rectus sheath?
Aponeuroses of the external oblique and half of the internal oblique
What forms the posterior wall of the rectus sheath?
Aponeuroses of half the internal oblique and of transversus abdominus
What is posterior to the rectus sheath and muscles?
Transversalis fascia, peritoneum and greater ommentum
What feature of the greater ommentum helps deal with infection?
Fat of GO can move to wall off an infection and create a local abscess
Where is the arcuate line and what is its significance?
About 1/2way between umbilicus and pubic crest
Where rectus sheath doesn’t surround rectus abdominis posteriorly, so is in direct contact with fascia
What is divarication of recti?
When linea alba is lax so when rectus abdominis contracts, muscle spreads apart
Who is divarication of recti more common in?
Women, who have had many children