Anterior Abdominal Wall Flashcards
What are the 3 landmarks of the Anterior Abdominal Wall?
Costal Margin (medial borders of 7-10th costal cartilages), iliac Crest, Inguinal Ligaments (Connection between Anterior Superior iliac spine and Pelvic Tubercle)
What are the 9 regions of the Abdomen?
What are the 3 Planes that form the 9 Regions?
Above Subcostal Plane
- Right and Left Hypochondriac
- Epigastric Region
Between Subcostal and Transtubercular Plane
-Right and Left Lumbar
-Umbilical Region
Below Transtubercular Plane
-Right and Left Inguinal Region
-Hypogastric Region
What are the 4 quadrants of the Abdomen?
What are the 2 planes that form the 4 quadrants?
Right and Left Upper Quadrant
Right and Left Lower Quadrants
(Median Plane and Transumbilical Plane
What are the 2 Layers of Superficial Fascia of the Anterior Abdominal Wall? (Both are below the Umbilicus)
- Camper’s Fascia
- Fatty
- Scarpa’s Fascia
- Membranous (Deep Layer)
What are the 4 major muscles of the Anterior Abdominal Wall
External Oblique, Internal Oblique, Transverse Abdominis, Rectus Abdominis
What is the Rectus Sheath?
Aponeurosis (Sheet-like tendon) of external and internal oblique, and the transversus abdominis.
What do you find above the arcuate line? (Parts of the Rectus Sheath Layer)
Anterior Layer - External Oblique aponeurosis and Half of internal oblique aponeurosis
Posterior Layer - Half of internal oblique aponeurosis and transversus abdominis aponeurosis
What do you find below the arcuate line? (Parts of the Rectus Sheath Layer)
Anterior Layer - External and Internal Oblique aponeuroses, Transversus Abdominis aponeuroses
Posterior Layer - NONE! You can now see the rectus abdominis muscle (covered with the transversalis fascia)
Semilunar Lines?
Lateral Border of the rectus abdominis muscle (ABS)
Linea Alba?
Junction of aponeuroses of the anterior abdominal wall muscles.
Located at the anterior midline of abdominal wall.
Extends from the xiphoid process to the pubic symphysis
Do the fibers of the rectus abdominis run the entire length of the muscle?
NO! Rectus Adbominis fibers run between 3-4 tendinous intersections
What are the 5 Umbilical/Peritoneal folds?
1 Median Umbilical Fold, 2 Medial Umbilical Folds, 2 Lateral umbilical folds
What does the Median umbilical Fold contain?
Contains the obliterated urachus (median umbilical ligament)
What does the Medial umbilical fold contain?
Contains the obliterated umbilical arteries (medial umbilical ligament)
What does the Lateral Umbilical fold contain?
Contains the inferior epigastric vessels
What are the 3 Peritoneal Fossae?
2 Supravesical Fossae (btw median umbilical fold and medial umbilical fold)
2 Medial inguinal Fossae/Hessselbach triangles (between medial and lateral umbilical Fold)
2 Lateral inguinal Fossae (lateral to lateral umbilical Fold)
What is the site of DIRECT inguinal hernias?
Medial inguinal Fossae / Hesselbach’s triangles
What is the site of INDIRECT inguinal hernias?
Lateral inguinal Fossae (which contains the deep inguinal rings)
Innervation and Function of External Oblique
Innervation: Ventral Rami of T7-L1
Function: Compress and support Abdominal Contents, Bilaterally flex trunk forward, individually they flex trunk laterally, rotate trunk
Innervation and Function of Internal Oblique
Innervation: Ventral Rami of T7-L1
Function: Compress and support abdominal contents, Bilaterally flex trunk forward, individually they flex trunk laterally, rotate trunk
Tranversus Abdominis
Innervation: Ventral Rami of T7-L1
Function: Compress and support abdominal contents
Rectus Abdominis
Innervation: Ventral Rami of T7-L1
Function: Compresses abdominal Content, Flexes Vertebral Column, Stabilizes anterior abdominal wall to control the tilt of the pelvis
Venous Drainage above Umbilicus?
Blood will drain through the thoracoepigastric vein toward the axillary vein
Venous Drainage below Umbilicus?
Blood will drain through the superficial epigastric vein toward the femoral vein
Caput Medusae
Obstruction of the umbilical veins (Ex: Liver cirrhosis causes this)
Lymphatic Drainage of Superficial Anterior Abdominal Wall
Lymph above umbilicus - drains toward axillary lymph node
Lymph below umbilicus - drains down toward superficial inguinal lymph node
Lymphatic Drainage of Deep Anterior Abdominal Wall
Lymph will drain into external iliac lymph node, common iliac lymph node, and lumbar lymph node.
All of these lead toward to the cisternai chyli.
What artery supplies blood to the Anterior Abdominal Wall?
Inferior epigastric artery (branches off of external iliac artery)
What SOMATIC nerves innervate the Anterior Abdominal Wall?
What are the functional components of these nerves?
Thoraco-abdominal nerves (intercostal nerves) (T7-T11)
Subcostal Nerve (T12)
illiohypogastric nerve (L1)
illioinguinal nerve (L1)
Functional Components: SA, SE, VE-SYM/POST, VA
These somatic nerves pass through neurovascular plane (between internal oblique and transversus abdominis muscles).
What CUTAENOUS Nerves innervate the Anterior Abdominal Wall?
What are the functional components of these nerves?
Anterior Cutaneous Nerves - Supply skin over rectus abdominis
Lateral Cutaneous Nerves - Supply skin over rest of anterior abdominal wall
Functional Components: SA, VE- SYM/POST, VA
* NO SE bcuz these nerves don’t have any muscles to innervate
What does the neurovascular plane pass between? (Somatic nerves pass through this plane)
Neurovascular Plane passes between internal oblique and transversus abdominis muscles.