Posterior Abdominal Wall Flashcards
What is the description of fascia
A continuous layer of connective tissue between peritoneum and muscle
What forms the rectus sheath
The aponeuroses of the transverse abdominal and the internal and external oblique muscles
What is the arcuate line of the rectus sheath
Horizontal line demonstrating the lower limit of the posterior layer of the rectus sheath
Name the three paired muscles of the posterior abdominal wall
- Quadratus lumborum
- Iliacus
- Psoas major
Where does the quadratus lumborum muscle travel from, and to
The iliac crest to the 12th rib and the transverse processes of L1-L4
What is the innervation of the quadratus lumborum muscle
Anterior rami of T12-L4
What is the function of the quadratus lumborum muscle
One = Bends trunk to the same side Both = Pressure, forced expiration and support for the 12th rib
Where does the iliacus muscle travel from, and to
The iliac fossa into the lesser trochanter of the femur (with the psoas; as the iliopsoas)
What is the innervation of the iliacus muscle
Femoral nerve
What is the functions of the iliacus muscle
Hip flexion
Where does the psoas major muscle travel from, and to
T12-L4 vertebrae (superficial) and L1-L5 vertebrae (deep) to the lesser trochanter of the femur (with the iliacus; as the iliopsoas)
What is the innervation of the psoas major muscle
Lumbar plexus direct branches L2-L4
What is the function of the psoas major muscle
One = Hip flexion and bends trunk laterally Both = Raises trunk from supine position (during sit ups)
What is the psoas minor
A long tendon lying anterior to the psoas major muscle
Where does the thoracic aorta pierce the diaphragm
The aortic hiatus at T12, where it becomes the abdominal aorta
What are the common branches of the abdominal aorta
- Inferior phrenic to diaphragm
- Lumbar and median sacral to abdominal wall
- Abdominal viscera, kidneys, ovaries/testes
Where are the common iliacs formed
Abdominal aorta bifurcates at L4
Where is the IVC formed
At L5, where the common iliac veins unite
How does blood from the gut enter the IVC
Through the hepatic veins from the liver
What lumbar veins tend to drain directly into the IVC
Lumbar veins 3 and 4
Where does the 5th lumbar vein tend to drain into
The iliolumbar vein; and then into the common iliac vein
Where does the ascending lumbar vein travel to
Travels superiorly where it communicates with the azygous and hemi-azygous veins
What lumbar veins tend to drain into the ascending lumbar vein
Lumbar veins 1 and 2
Where do the gonadal vessels branch from the abdominal aorta
At L2
What is the innervation of the posterior abdominal wall
Sympathetic innervation from T1-L1/L2
What do autonomic fibres form within the abdomen
Plexuses using fibres from the sympathetic chains around the anterior portion of the aorta
What nerve supplies the parasympathetic innervation of the foregut and midgut
Vagus nerve; cranial nerve X
What nerves supplies the parasympathetic innervation of the midgut
Pelvis splanchnic nerves; S1-S4
What nodes does lymph from the pelvis travel to
Iliac nodes
What nodes does lymph from the body wall, kidneys and testes/ovaries travel to
Para-aortic (lateral) nodes
What nodes does lymph from the digestive tract travel to
Pre-aortic nodes
Where does the thoracic duct begin
At the cisterna chyli, at L1/L2
What is the innervation of the lumbar plexus
Anterior rami of L1-L4
What are the 6 nerves of the lumbar plexus
- Iliohypogastric
- Ilioinguinal
- Genitofemoral
- Lateral femoral cutaneous
- Obturator
6 Femoral
What is the root value of the iliohypogastric and ilioinguinal nerves
Anterior rami L1
What information does the iliohypogastric nerve supply
Sensory = Lateral gluteal and pubic skin Motor = Internal oblique and transversus abdominis
What information does the ilioinguinal nerve supply
Sensory = Skin on medial thigh and the scrotum/penis or mons pubis/labia majora Motor = Internal oblique and transversus abdominis
What is the root value of the genitofemoral nerve
Anterior rami L1-L2
What information does the genitofermoral nerve supply
Sensory = Scrotum or mons pubis and skin of the upper anterior thigh Motor = Cremasteric muscle
What is the root value of the lateral cutaneous femoral nerve
Anterior rami of L2-:3
What information does the lateral cutaneous femoral nerve supply
Sensory = Skin on the anterior and lateral thigh
What is the root value of the obturator nerve
L2-L4
What information does the obturator nerve supply
Sensory = Skin on medial thigh Motor = Obturator externus and medial compartment of thigh
What is the root value of the femoral nerve
L2-L4
What information does the femoral nerve supply
Sensory = Anterior thigh and lateral leg Motor = Pectineus and iliacus muscles, and the anterior compartment of the thigh
