10/6: Anterolateral Abdominal Wall

Question 1

Name the abdominal wall layers from superficial to deep

Answer 1

Skin
Camper’s Fascia (fatty SF)
Scarpa’s fascia (membranous SF)
3 layers of muscle
Transversalis fascia
Extra peritoneal fat
Parietal peritoneum
Abdominal organs

Question 2

What is the skin?

Answer 2

Outermost layer

Question 3

What fat is stored in the Camper’s fascia (fatty SF)?

Answer 3

subcutaneous fat is stored

varies in thickness

Question 4

What nerves and vessels run in camper’s fascia to get to skin?

Answer 4

Cutaneous nerves and vessels
has neurovasculature

Question 5

Scarpa’s fascia (membraneous SF)

Answer 5

Thin, loosely arranged CT w/ vessels and veins
No fat

Question 6

What does the scarpia’s fascia tightly arrange to form?

Answer 6

Fibers tightly arrange to form membrane

Question 7

Where is the scarpa’s fascia only found in?

Answer 7

Anteriorly

Question 8

What do the 3 layers of muscle have the same organization as (broad flat sheets)

Answer 8

intercostals

Question 9

What are the 3 layers of muscle?

Answer 9

External oblique, internal oblique, and transversus abdominus

Question 10

transversalis fascia

Answer 10

CT layers that line whole anterior and lateral abdominal wall

Question 11

Extraperitoneal fat

Answer 11

Similar to body fat in composition; varies in thickness (outside of peritoneum)

Question 12

What does the parietal peritoneum secrete?

Answer 12

Fluid to provide lubricant forming frictionless movement

Question 13

Whatis the parietal peritoneum?

Answer 13

lining of body

Question 14

What are the group functions of the abdominal wall muscles?

Answer 14

Movement of the trunk

Question 15

What are the bilateral and unilateral functions of the trunk?

Answer 15

Bilateral: pure flexion
unilateral: lateral flexion and rotations/twisting

Question 16

What are the insertions of the rectus abdominis?

Answer 16

4 tendinous insertions into the superficial division of the rectus sheath

Question 17

Where is the insertion of the rectus abdominis?

Answer 17

Costal cartilages and xiphoid processes of sternum

Question 18

How do the fibers of the rectus abdominis run?

Answer 18

Vertically
about 3 times as wide superiorly as inferiorly

Question 19

Where is the origin of the rectus abdominis?

Answer 19

pubis

Question 20

What gives six pack appearance?

Answer 20

Rectus abdominus due to 4 tendenous insertions into the superfiical division of the rectus sheath

Question 21

Where do external oblique fibers run?

Answer 21

Down and in towards midline (same as external intercostals)

Question 22

Where does the inguinal ligament run?

Answer 22

From anterior superior iliac spine to public spine

Question 23

Where does the external oblique attach from?

Answer 23

Ribs and costal cartilages laterally to iliac crest and anterior superior iliac spine

Question 24

What is the aponeurosis

Answer 24

Abrupt transition from muscle fibers to ligamentum at location of anterior superior iliac spine

Question 25

Where does aponeurosis insert on?

Answer 25

Linea alba and pubic bone on opposite side

Question 26

Where does the internal oblique attach from?

Answer 26

Iliac spine and deep inguinal ligament to linea alba (where the aponeuroses come together)

Question 27

What muscle fibers are fan shaped?

Answer 27

Internal oblique

Question 28

What is the innermost layer of abs?

Answer 28

Transversus abdominis

Question 29

Where does transversus abdominis attach from?

Answer 29

Lateral edge of transversalis fascia, iliac crest and internal oblique fascia to linea alba

Question 30

What does the internal oblique have?

Answer 30

Fibers that originate from the deep surface of the inguinal ligament

Question 31

What does the internal oblique give rise to?

Answer 31

lower fibers of transversus abdominis

Question 32

What does the abdominal wall gap located?

Answer 32

Between inguinal ligament and pelvis

Question 33

What does the abdominal wall gap function to allow?

Answer 33

Neurovascular structures (femoral artery, vein, and nerve) and iliopsoas to enter and be distributed into the lower limb

Question 34

Above the arcuate line in the top 3/4th's of the rectus sheath, where do the EAO aponeuroses pass?

Answer 34

Superficial to the rectus abdominus and ends at linea alba

Question 35

Above the arcuate line in the top 3/4th's of the rectus sheath, what do the IAO aponeuroses split into?

Answer 35

Two thinner layers (one superficial that fuses with EAO to form superficial half of rectus sheath) (other later fuses with TA aponeuroses to from deep half of rectus sheath)

Question 36

Above the arcuate line in the top 3/4th's of the rectus sheath, where do the TA aponeuroses pass?

Answer 36

deep to rectus abdominis and ends at linea alba

Question 37

What is the pathway of aponeuroses in the bottom 1/4ths below the arcuate line?

Answer 37

EAO, IAO, and TA all pass superficially to the rectus abdominis and fuse together to form a superficial rectus sheath

Question 38

What does the abdominal wall gap allow for communication?

Answer 38

Between body cavity and lower limb

Question 39

What is sensory innervation of the skin over the anterior abdominal wall provided by?

Answer 39

Ventral rami lower 5 intercostal nerves (T7-11) Subcostal nerve (T12) Iliohypogastric/ilioinguinal nerves (L1)

Question 40

What nerves provide somatic motor innervation to the anterior abdominal wall muscles?

Answer 40

Same ones as for the anterior lower 5 intercostal nerves (T7-11) Subcostal nerve (T12) Iliohypogastric/ilioinguinal nerves (L1)

Question 41

Where do arteries run?

Answer 41

In the rectus sheath deep to the muscle

Question 42

Where does lymph from skin above the umbilicus (including the back and upper limb) drain to?

Answer 42

Axillary nodes

Question 43

Where does lymph from skin below the umbilicus (including the back, pelvis, perineum, and lower limb) drain to?

Answer 43

Superficial inguinal nodes

Question 44

What is the main function of the abdominal wall?

Answer 44

Movement of the trunk

Question 45

What are less obvious functions of the abdominal wall muscles?

Answer 45

- Stabilizaiton of the trunk during strenuous physical effort (Valsalva's maneuver) - Forceful expiration - Coughing and sneezing - urination and defecation - labor deliver

Question 46

What are the functions of the trunk?

Answer 46

Flexion (pure) Lateral flexion Rotation (twisting)

Question 47

How do the abdominal wall muscles affect the abdominal cavity?

Answer 47

1. Decrease abdominal cavity volume/increase intraabdominal pressure 2. Abdominal organs increase pressure in thorax and pelvis