Anterior Abdominal Wall Flashcards
What are the 4 boundaries of the anterior abdominal wall?
1) Superior – right and left costal margins, xiphisternal joint
2) Inferior – a line on either side connecting the ASIS to the pubic symphysis
3) Lateral – vertical lines ascending from the ASIS on each side
4) Posterior – lumbar paravertebral musculature
Location of subcostal plane
line through the most inferior points of the costal cartilage, 10th costal
cartilage. The line passes through the body of L3 vertebra
Location of transtubercular plane
line passes through the iliac tubercles at the level of the L5 vertebra
Location of sagittal plane
mid-clavicular lines, extends inferior from the mid-clavicle to the mid-inguinal point.
Upper region consists of?
(1) Right hypochondriac
(2) Epigastric
(3) Left hypochondriac
Middle region consists of?
(1) Right lumbar
(2) Umbilical
(3) Left lumbar
Lower region consists of?
(1) Right inguinal
(2) Hypogastric
(3) Left inguinal
Organs within the RUQ
Liver Gallbladder Right suprarenal gland Right kidney Ascending colon: superior part
Organs within the LUQ
Spleen Stomach Pancreas – body and tail Left kidney Transverse colon (left half), Descending colon (superior part)
Organs within the RLQ
Cecum Vermiform Appendix Right ovary Right ureter Most of the ileum
Organs within the LLQ
Sigmoid colon Descending colon: inferior part Left ovary Left ureter Left spermatic cord
OINA of Ext. Abdominal Oblique
0 – external surface of the 5th to 12th ribs
I – linea alba, pubic crest, iliac crest, pubic symphysis
N – Inferior 5 thoracic nerves and subcostal nerve(T12) and iliohypogastric
A – flex and rotate trunk, laterally rotate the trunk, compress abdominal contents
OINA of Int. Abdominal Oblique
O – Thoracolumbar fascia, anterior iliac crest, lateral half of inguinal ligament
I – linea alba, pubic crest, ribs 10-12 inferior surface
N – lower 5 thoracic nerves, subcostal, iliohypogastric
A – flex and rotate the trunk, laterally rotate the trunk, compress abdominal contents
OINA of Transverse Abdominis
0 – thoracolumbar fascia, iliac crest, lateral one third of the inguinal ligament, internal surface of costal cartilage’s 7 to 12
I – linea alba, pubic crest, pubic symphysis
N – lower 5 thoracic nerves, subcostal, iliohypogastric
A – compress and support abdominal viscera
OINA of Rectus Abdominis
0 – pubic symphysis, pubic crest
I – xiphoid process, 5th and 7th costal cartilage’s
N – lower 5 thoracic nerves, subcostal, iliohypogastric
A – flexes trunk and tenses anterior abdominal wall
Rectus Sheath-Structure
It is a dense fibrous sheath enclosing the rectus abdominis muscle.
It is formed by the fusion of the aponeuroses of the abdominal muscles.
Rectus Sheath above the level of the Umbilicus - Anteriorly
Anteriorly – external abdominal oblique aponeurosis and ½ of the Internal abdominal oblique aponeurosis
Rectus Sheath above the level of the Umbilicus - Posteriorly
Posteriorly - ½ of the Internal abdominal oblique aponeurosis and the aponeurosis of the Transversus abdominis
The anterior and posterior walls meet and fuse in the anterior median line called the _____.
Linea Alba
Rectus Sheath below the level of the Umbilicus - Anteriorly
Anteriorly – The aponeurosis from all three muscles now pass anteriorly over the rectus abdominis with no fascia from the muscle passing posteriorly
Rectus Sheath below the level of the Umbilicus - Posteriorly
Posteriorly – a thin fascial film remains posteriorly that protects the rectus abdominis from rubbing against the abdominal contents.
The point of transition were all three aponeurosis pass anteriorly is marked by the ______.
Arcuate Line
Innervation of Ant. Abd. Wall
It is supplied by the ventral primary rami of thoracic spinal nerves of T6 – T11, ventral primary ramus of T12 or subcostal nerve and the iliohypogastric and ilioinguinal nerves from the ventral primary ramus of L 1
Arterial Supply of Ant. Abd. Wall
- Superior epigastric - branch of the internal thoracic artery
- Inferior epigastric - a branch of the external iliac
- They both enter the rectus sheath posterior to the rectus abdominis and anastomoses with the rectus muscle - The posterior intercostal arteries that accompany the intercostal nerves also contribute to the arterial supply of the anterior abdominal wall
- Additional supply comes from the direct branches of the abdominal aorta and lumbar arteries