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.
What is the inferior margin of the transversalis fascia called?
iliopubic tract
What do the inguinal ligament fibers help to form?
Reflected inguinal ligament, Lacunar ligament, pectineal ligament
Where does inguinal canal begin and end?
Begins at the deep inguinal ring and ends at the superficial inguinal ring
What passes through the inguinal canal in 1) men and 2) women?
1) Spermatic Cord (vas deferens), 2) Round Ligament
What nerves are found in the inguinal canal?
ilioinguinal nerve (L1) + genital branches of genitofemoral nerve
What 3 fibers form the aponeurosis that strengthen the superficial inguinal ring?
Medial, lateral, and intercrural fibers
The fiber aponeurosis of what muscles forms the superficial inguinal ring?
External Oblique muscles
What structures (anatomically) does the Inguinal canal contain?
2 walls
1. Anterior Wall
2. Posterior Wall
Roof
Floor
What forms the anterior wall of the inguinal canal?
External oblique aponeurosis which runs down the entire length of inguinal canal
What forms the posterior wall of the inguinal canal?
Transversalis Fascia
What forms of the ROOF of the inguinal canal?
Laterally and Medially?
Transversalis Fascia form the LATERAL part of the roof.
External Oblique aponeurosis form the MEDIAL part of the roof.
What forms the FLOOR of the inguinal canal?
Inguinal ligament
What are the 3 borders that form Hesselbach’s triangle or the medial inguinal fossae?
Medial border - Lateral border of the rectus abdominis muscle (semilunar lines)
Lateral Border - Inferior epigastric vasculature
Inferior border - inguinal ligament
What fills in most of Hesselbach’s triangle?
What forms this structure?
inguinal falx (conjoint tendon)
- Formed by merging fibers of the internal oblique and transverses abdominis aponeurosis coming together.
In terms of DIRECT herniation, is the specific spot filled in by the inguinal falx (conjoint tendon)?
NO!
What is the hernial sac covered with in a DIRECT (acquired/rare) inguinal hernia?
Hernial Sac is covered by transversalis fascia.
Does a DIRECT (acquired/rare) inguinal hernia traverse the entire inguinal canal?
DIRECT inguinal hernia never enters the scrotum or labia majora because it does NOT transverse the entire inguinal canal.
How does a DIRECT (acquired/rare) inguinal hernia pass anatomically in relation to where it’s located?
Direct inguinal hernia passes MEDIALLY to inferior epigastric vessel and LATERALLY to the conjoint tendon in the Hesselbach’s triangle.
What covers the hernial sac of a DIRECT (acquired/rare) INGUINAL HERNIATION?
Transversalis fascia
How does a INDIRECT (congenital/common) inguinal hernia pass anatomically in relation to where it’s located?
INDIRECT inguinal hernias pass LATERAL to the inferior epigastric vessel.
Does a INDIRECT (congenital/common) inguinal hernia traverse the entire inguinal canal?
YES! The INDIRECT inguinal hernia passes through the deep inguinal ring, runs the entire inguinal canal, exits the superficial inguinal ring, and then ENTERS the scrotum.
20x more common in males
What is the hernial sac covered with in a INDIRECT (CONGENITAL/COMMON) inguinal hernia?
Spermatic Cord
What is the external spermatic fascia derived from?
What layer of fascia is on top of the external spermatic fascia?
External oblique aponeurosis
Dartos Fascia (tunica dartos)
What is the cremasteric fascia derived from?
Internal oblique aponeurosis
What muscle does the cremasteric fascia contain?
What is its function?
Why is that important?
Cremasteric muscle (skeletal muscle) formed from the internal oblique muscle fascicles
Cremaster draws the testes superiorly when cold, but relaxes them when its hot.
It keeps a constant temperature to allow spermatogenesis (sperm formation) to occur efficiently.
What is the innervation of the cremaster muscle?
GENITAL branch of the genitofemoral nerve
What is the cremasteric reflex?
How do you turn on/test the reflex?
What nerves are tested during to cremasteric relfex?
Cremasteric reflex is the rapid elevation of the testes on the same side.
To test the reflex, stroke the skin of the medial thigh (superiorly)
Ilioinguinal nerve and genitofemoral nerves
What is the internal spermatic fascia derived from?
Transversalis fascia (NO APONEUROSIS HERE BCUZ THIS IS FASCIA)
What layer is found ONLY at the level of testes?
Tunica vaginalis. Has both a visceral layer (inside/on the testes) and a parietal layer.
What is the vas deferens? What does it do?
What is the procedure called when the vas deferens is ligated?
Vas deferens is a muscular tube that takes sperm from epididymis to the ejaculatory duct.
Vasectomy is when it’s taken out.
What is the pampiniform venous plexus?
What is it called when they become dilated?
pampiniform venous plexus is about 12 veins that converge to form the testicular veins.
Dilated pampiniform venous plexus is called VARICOCELE
Where is sperm formed?
What does this structure lead to?
Seminiferous tubules
Seminiferous tubules are joined by straight tubules to the rete testis.
What is the outer surface of the testes? (The 1st layer on the testes)
Tunica Albuginea
What are the layers in order on the testes? (outer most –> inner most)
Scrotal skin –> tunica dartos –> external spermatic fascia –> cremasteric fascia –> cremasteric muscle –> internal spermatic fascia –> parietal layer (tunica vaginalis) –> serious cavity of testes –> visceral layer (tunica vaginalis) –> tunica albuginea
What is the sperm pathway?
Formed in seminiferous tubules –> rete testes–> efferent ductules–> epididymis (where sperm mature)
How is the epididymis formed?
Epididymis duct twists a lot and forms the epididymis.
What are the regions of the epididymis ?
Head
- superior expanded portion of epididymis that contains lobules that are formed by the coiling of 12-14 efferent ductules
Body
- convoluted duct of epididymis
Tail
- continuous with the ductus (vas deferens)
(remember what vas deferens does and you can make it easy to remember)
What muscle gives the wrinkling effect of the scrotum?
What is this muscle derived from?
The dartos muscle (contained in the dartos fascia)
Dartos muscle is derived from Scarpa’s fascia.
What separates both testes?
Scrotal Septum
What is the order of blood supply/drainage of the testes?
Blood is supplied via the testicular arteries then it goes to the pampiniform venous plexus and then to the testicular veins
What is the order of lymphatic drainage of the testes?
Lymph goes to left and right lumbar lymph nodes and the pre-aortic lymph nodes.
What innervates the testes?
What are functional components?
Testicular plexus (autonomic innervation)
sym/post, para/pre, va
Where does cancer of the testes go to first?
Goes first to lumbar lymph nodes
What drains the lymph of the scrotum?
Superficial inguinal lymph node
Where does cancer of the scrotum go to first?
Goes first to the superficial inguinal lymph node
What is hydrocele of the testes?
This is when the XS fluid in a persistent processus vaginalis
What is hydrocele of the spermatic cord?
XS fluid in the spermatic cord and in the persistent processus vaginalis
What is HEMATOCELE of the testes?
Collection of blood in the tunica vaginalis cavity (between visceral and parietal layer)
