Anterolateral abdominal wall Flashcards
The abdominal cavity is larger than it appears externally. Why?
because the respiratory diaphragm arches superiorly under the rib cage.
The abdominal cavity contains the……… cavity and………….. viscera.
peritoneal abdominal
What is Important to remember about the domes of the diaphragm?
The diaphragm has a right dome that rises as high as the 5th rib and a left dome that rises as high as the 5th intercostal space during expiration (So the RIGHT dome is HIGHER!)
The upper abdominal organs (ex: liver and spleen) are protected by the lower ribs and costal cartilages of the thoracic wall. How may they be injured?
By fractures of the lower ribs
The abdominal wall consists of………… vertebrae posteriorly, and the wings (alae) of the ilia laterally. There are layers of what located anterolaterally in the interval between the ribs and pelvis?
all 5 Lumbar vertebrae skeletal muscle and aponeurosis
For the localization of internal organs or patient symptoms, the abdomen is often subdivided into how many quadrants?
4
For more precise localization, the abdomen may be subdivided into nine regions by two vertical midclavicular planes, and two horizontal planes:
The subcostal plane: through the 10th costal cartilages (or the trans pyloric plane) - The trans tubercular plane: through the tubercles of the iliac crest (level of Lv5)
The superficial fasciaof the anterolateral abdominal wall Contains a variable amount of fat, and also contains cutaneous nerves, including branches of:
–Thoracoabdominal nerves (T7-11). This is why pain from the lower thoracic wall (ex: pleurisy) may be referred to the abdomen. Also note that T10 innervates the umbilicus level
–Subcostal nerve (T12)
–Iliohypogastricand ilioinguinal nerves (L1)
Arteries of the anterolateral abdominal wall include which superficial vessels?
- Superficial epigastric arteries
- superficial circumflex iliac arteries (from the femoral artery)
The deeper arteries of the abdominal wall include what?
– Inferior epigastric artery (external iliac) and superior epigastric artery (internal thoracic). Their anastomosis is a potential source of collateral circulation
–Deep circumflex iliac artery (from the external iliac artery)
* Remember that veins of similar names accompany the arteries.
There are superficial collateral routes for venous return to the heart if the inferior or superior vena cava is obstructed. Desribe this!
(on each side) the anastomosis of thesuperficial epigastric vein (femoral vein) with the lateral thoracic vein (axillary vein) form the thoracoepigastric vein.
When it comes to lymphatic drainage from the anterolateral abdominal wall, the superficial lymphatic vessels located………… drain mainly upward to axillary lymph nodes, and the ones located……………. drain downward to the superficial inguinal lymph nodes.
above the umbilicus
below the umbilicus
Deep lymphatic vessels accompany what?
deep veins of the abdominal wall
The superficial fascia (subcutaneous connective tissue) of the anterior abdominal wall consists of how many layers?
- Above the level of the umbilicus it consists of a single fatty layer
- Inferior to the umbilicus it consists of two layers
The superficial fascia (subcutaneous connective tissue) of the anterior abdominal wall that is inferior to the umbilicus consists of two layers. What are these 2 layers?
– A superficial fatty layer, or Camper’s fascia
– A deep membranous layer, or Scarpa’s fascia
Scarpa’s fascia in men is continuous with the superficial fascia of the scrotum and the perineum. Why is this important clinically?
extravasated urine from a ruptured penile urethra, or an infection, may spread upward into the anterior abdominal wall deep to the Scarpa’s fascia!
* however, fluid doesn’t spread downward into the thigh.
There are 5 muscles in the anterolateral abdominal wall, ……….flat muscles whose fibers begin posterolaterally, pass anteriorly and are replaced by an aponeurosis towards the midline, and……… vertical muscles near the midline.
What is the nerve supply for these muscles?
3
2
•Nerve supply : anterior rami of T7-T12 spinal nerves
The 3 flat muscles on each side of the anterolateral abdominal wall are:
- external oblique
- internal oblique
- transversus abdominis
Nerve supply : anterior rami of T7-T12 spinal nerves
The 2 vertical muscles near the abdominal midline are:
rectus abdominis and pyramidalis.
Nerve supply : anterior rami of T7-T12 spinal nerves
The external oblique muscle arises from the lower 8 ribs and courses what direction?
It has posterior fibers inserting into the iliac crest and a broad EXTERNAL OBLIQUE APONEUROSIS anteriorly that helps form the anterior layer of the rectus sheath.
At the midline, linea alba aponeurotic fibers intersect with those of the other side.
inferomedially
Between the anterior superior iliac spine and the pubic tubercle, the external oblique aponeurosis has a rolled-under inferior free margin. What does this form?
The inguinal ligament.