Lecture 1: Anterior Abdominal Wall

Question 1

What are the divisions of the abdomen?

Answer 1

H: Hypochondrium
L: Lateral flank
I: Inguinal
E: Epigastric
U: Umbilical
P: Pubic

Left/right: H,L,I
Middle: E,U,P
+ all 4 quadrants

Question 2

Where is the transpyloric plane?

What organs are on this level?

Answer 2

L1 level

Organs: gall bladder fundus, pylorus,pancreatic neck, root of transverse mesocolon, kidney hila

Vessels: SMA origin, hepatic portal vein

Question 3

Where is the subcostal plane and what is found here?

Where is the transtubercle plane and what is found here?

Where is the interspinous plane and what is found here?

Answer 3

• L3, inferior 10th cartilage; transverse colon
• L5 between iliac tubercles; iliocecal junction
• S2 between ASIS; appendix, sigmoid colon

Question 4

What characterizes the abdominopelvic cavities?
Located?
Separated by?
Lined by?

Answer 4

Located between thoracic and pelvic diaphragm
A separated from P by pelvic inlet
periotneum (continuous between A and P)

Question 5

What are the borders of the anteriolateral abdominal wall?
Location?
Made of?

Answer 5

Upper border: catilage 7-10
Lower border: inguinal ligament and pelvic bones

-mostly muscle and aponeurosis

Question 6

What are the layers of the anteriolateral abdominal wall?

Answer 6

skin > camper’s fascia > scarpa’s fascia > aponeurosis > transversalis fascia > extraperitoneal fat > parietal peritoneum

Question 7

What is the difference between Camper’s and Scarpa’s fascia?

Answer 7

-fatty layer of superficial fascia vs. membranous underlying CT layer of superficial fascia

Question 8

What happens to Scarpa’s fascia in the perineum and the lower limb?

Answer 8

Perineum: continuous with Colle’s fascia

Lower limb: fused with fascia lata

Question 9

OINA:

External oblique muscle

Answer 9

O: outer lower 6 ribs
I: linea alba and aponeurosis
N: ventral rami T7-12 (intercostal ns.)
A: compress abdomen and increase intra-abdominal pressure, move trunk and retain posture

Question 10

OINA:

Internal Oblique muscle

Answer 10

O: iliac crest and thoracolumbar fascia
I: lower 10-12 ribs, aponeurosis, linea alba, forms conjoint tendon/inguinal falx in the lower part
N: T7-L1
A: compress and supports viscera, lateral flexion and rotation

Question 11

What happens to the aponeurosis of the IOM?

Answer 11

Upper 3/4 of muscle: splits the rectus muscle

Lower 1/4: all go anteriorly

Question 12

OINA:

Transversus Abdominis muscle

Answer 12

O: lower 7-12 rib, thoracolumbar fascia, iliac crest and upper inguinal ligament
I: linea alba, pecten pubis and pubic crest
N: T7-L1
A: compresses and supports viscera

Question 13

OINA:

Rectus Abdominis Muscle

Answer 13

O: pubic symphysis and pubic crest
I: xiphoid processs and outer 5-7th cartilage
N: T7-12
A: flex and compress abdomen

Question 14

What level are the tendinous insertions in the rectus abdominis muscles at?

What borders the rectus abdominis m. laterally?

Answer 14

• xiphoid, midway, umbilicus (form the 6 pack)

- linea semilunaris

Question 15

What muscle is missing in 20% of patients?

Answer 15

pyramidis muscle, small muscle in lower rectus abdominis

Question 16

Describe the rectus sheath

Answer 16

Anterior:
Aponeurosis of EO, lower 1/4 IO, lower 1/4 TA

Posterior:
TA aponeurosis

All the aponeurosis will merge anterior below the arcuate line, connecting to the trasversalis fascia behind the rectus sheath

Question 17

What are the main nerves of the anterior abdominal wall?

Be able to draw them

Answer 17

• thoraco-abdominal ns. (T7-11) with their lateral cutaneous branches
• subcostal, iliohypogastric and ilioinguinal

Question 18

What does the subcostal n. innervate?
What does the iliohypogastric n. innervate?
What does the ilioinguinal n. innervate?

Answer 18

• sensory superior to the iliac crest
• IO and TA motor, sensory to upper inguinal and hypogastric regions
• lower iO and TA motor, sensory to lower inguinal, anterior genitals and medial thigh

Question 19

What are the arteries of the anterior abdominal wall?

Be able to draw them

Answer 19

-Lumbar arteries
-Superficial epigastric a.
superficial circumflex a
deep circumflex iliac a
inferior epigastric a
superior epigastric a.

Question 20

What folds are found on the interior surface of the anterior abdominal wall?
Fossas?

Identify this on slide image

Answer 20

• median (from urachus), medial (from umbilical arteries), lateral umbilical folds (fold from inferior epigastric a)
• medial and lateral inguinal fossas
• supravesicular fossa

Question 21

Which nodes do superficial vessels above the umbilicus drain?

Which nodes do superficial vessels below the umbilicus drain?

Which nodes to deep lymph vessels go?

Answer 21

Axillary and some to parasternal nodes

Superficial inguinal nodes

travel with deep veins of the abdominal wall

Question 22

Be able to draw/identify where the common abdominal incisions are

Answer 22

Ok

Question 23

What incision do you make if you wanna...
access the gall bladder? 
appendix?
peritoneum? 
obstetrical/gynecological structures?
make a rapid incision?

Answer 23

Subcostal
Gridline
Paramedian (through the rectus muscle)
Suprapubic
Midline (since there are few vessels and nerves here)