Anterior abdominal wall Flashcards
what are the three layers of the thoracic wall and the way in which they travel
- External – anterior inferior
- Internal – anterior superior
- Innermost – going same was as internal intercostal
what is the three lateral layers of the abdominal wall and they way in which they travel
- external oblique - anterior inferior
- internal oblique - anterior superior
- tranversus abdominis - transverse (horiztonal)
what is the anterior wall in the abdomen
rectus abdominis
where does the external oblique and internal oblique and the transversus abdominis end
- they all end at the midclavicular line where an aponeurosis begins
what is the aponeurosis
- Aponeurosis is a tendon – it is a thin white flattened sheet of tendon
how does the Aponeurosis attach to each other (there is one on each side)
attaches to the other aponeurosis on the other side at the midline which is called the linea alba
describe the external oblique muscle
- the most superficial layer
- its fibres run in an anterior inferior direction
- Attach to the ribs superior and inferiorly attach to the iliac crest
- Muscle fibres end at mid clavicular line where the aponeurosis begins
- Aponeurosis attaches to the anterior superior iliac spine and the pubic tubercle this creates the inguinal ligament
describe the internal oblique muscle
- Middle layer
- Its fibres run in an anterior superior direction
- Attach to the ribs superiorly and the iliac crest inferiorly
- The sheet of muscle ends at the midclavicular line and then becomes aponeurosis
describe the transverses abdominis
- the deepest layer
- its fibres run in a transverse direction
- This means they pass horizontally across the abdomen
- Ends at the midclavicular line and then becomes an aponeurosis sheet
describe the rectus abdominis
- Extends from the costal margin (xiphoid process) superiorly to the pubic symphysis inferiorly
- The muscle is broken up into lots of different parts
- In between the muscle fibres there are tendon intersections
- In the midline there is the linea alba
what is the linea alba
fibrous structure that run down the midline that is where the apenrosis from the lateral abdominal muscles such as the external oblique attach
what is the rectus sheath
- this is how the rectus abdominis is covered with the Aponeurotic sheet that is derived from the aponeuroses of external oblique, internal oblique and transversus abdominis
what is the arcuate line
– this is below the arcuate line the structure of the rectus sheath changes and all run the aponeurosis run anterior to the rectus abdominis
describe the rectus sheath
- External oblique and half of internal oblique run anterior aperunosis to rectus abdominis
- Transversus abdominis and half of internal oblique run posterior apernuersis to rectus abdominis
what are the arteries in the thorax
- Thoracic aorta – gives on posterior intercostal artery
- Internal thoracic artery – gives of anterior intercostal artery
what artery goes from the thorax into the abdomen
internal thoracic artery
what does the internal thoracic artery run
- Internal thoracic artery run anterior to the diaphragm and then enter the abdomen
what happens when the internal thoracic artery enters the abdomen
this is where they change their name to the superior epigastric artery
what does the superior epigastric artery supply
rectus abdominis
what is the inferior epigastric artery a branch from
- There is also the inferior epigastric artery this is a branch from the external iliac artery
what does the inferior epigastric artery supply
these also supply the rectus abdominal – runs along the posterior aspect of the rectus abdominis and superiorly
what do the lower intercostal and lumbar arteries supply
- Lower intercostal and lumbar arteries supply blood to the lateral abdominal wall
where is the pubic tubercle
either side of the pubic symphysis
What does the external oblique attach to
- External oblique attaches to the anterior superior iliac spine and the pubic tubercle which is either side of the pubic symphysis
what is the inguinal ligament
- Inferior border of external oblique is called the inguinal ligament
what passes under the inguinal ligament
- The femoral artery, femoral nerve and femoral vein passes underneath it