Lecture 43 - Abdominal Wall

Question 1

Right Upper Quadrant (RUQ)

Answer 1

Gall bladder, right kidney, right lobe of liver

Question 2

Left upper quadrant (LUQ)

Answer 2

Left lobe of kidney, spleen, stomach

Question 3

Right lower quadrant (RLQ)

Answer 3

Cecum, appendix, most of ileum

Question 4

Left lower quadrant (LLQ)

Answer 4

Left ovary, sigmoid colon, left uterine tube

Question 5

Medial plane

Answer 5

Vertical line from xiphoid process to pubic bone

Separates left and right side

Question 6

Trans umbilical plane

Answer 6

Horizontal plane through umbilicus and intervertebral disc of L3/L4

Separates inferior and superior abdomen

Question 7

Bony elements of abdominal walls

Answer 7

 Lumbar vertebrae (L1-5) + IV discs
 Superior expanded iliac crests
 Costal margin (ribs 11 and 12, costal cartilage, xiphoid process

Question 8

muscular elements of abdominal wall

Answer 8

 Held together with thick fascia and tendinous sheets
 Mostly for posture and compression of abdominal cavity
 Protect and support viscera best when well-toned
 When weak or stretched (i.e. during pregnancy) abdomen can become pendulous (pot belly)

Question 9

posterior abdominal wall

Answer 9

 Muscles lateral to the vertebral column extending to and through the pelvis

Question 10

lateral abdominal wall

Answer 10

 Three layers of obliquely oriented mm

Question 11

anterior abdominal wall

Answer 11

 Vertical mm extending from thorax to pelvis

Question 12

Understand the anatomical arrangement of the layers of abdominal fascia and muscular aponeuroses

Answer 12

o Superficial fascia
 2 layers: fatty connective tissue (caper’s fascia)
 Deeper membranous layer (Scarpa’s fascia)
o Rectus sheath
 Layering of the aponeuroses of the abdominal mm
 Encloses the rectus abdominis
o Transversalis fascia
 Deep fascia separating the abdominal wall and the abdominal contents
o Peritoneum
 Lining of the abdominal wall that surround the visceral organs

Question 13

rectus sheath

Answer 13

 Sheath-like tendons of external oblique, internal oblique and transverse abdominus that encloses rectus abdominus
 Sheaths meet at midline to form linea alba

Question 14

inguinal ligament

Answer 14

 Dense band interior most aponeurosis of external oblique
 Attach at ASIS (anterior superior iliac spine) and pubic tubercle

Question 15

inguinal canal

Answer 15

 Oblique passage (4cm long) parallel and superior to inguinal ligament
 Formed in relation to relocation of gonads during fetal development
 Contains spermatic cord (males) or round ligament of uterus (females), and neurovascular structures that serve the pelvis

Question 16

Describe the features of the abdominal cavity

Answer 16

 Cylindrical space contained within the abdominal wall
 Contains visceral organs surrounded by peritoneum
 Contains neurovascular structures passing from the thorax into the pelvis and lower limb

Question 17

Describe the features of the peritoneum

Answer 17

 Similar to pleura of lungs
 Parietal peritoneum lines abdominal wall
 Visceral peritoneum covers visceral organs
 Peritoneal cavity – potential space created between parietal and visceral peritoneum

Question 18

Understand the difference between peritoneal and retroperitoneal

Answer 18

o Some organs positions behind peritoneum – retroperitoneal
o Intraperitoneal = enveloped in peritoneum, reflections of peritoneum form mesenteries that attach the gut tube to the abdominal wall
o Retroperitoneal = organs passing between peritoneum and posterior abdominal wall (anterior surface lined with peritoneum, posterior surface lined with other types of protective fascia)

Question 19

Blood supply of abdominal wall

Answer 19

o Superior
 Superficial = branch of the internal thoracic artery (musculophrenic)
 Deep = branch of internal thoracic artery (superior epigastric)
o Inferior
 Superficial = branches of the femoral artery (superficial epigastric and superficial circumflex iliac arteries)
 Deep = branches of the external iliac artery (inferior epigastric artery and deep circumflex artery)
o Lateral wall
 Intercostal artery from ribs 10 and 11 and subcostal artery

Question 20

Venous drainage of abdominal wall

Answer 20

Venous drainage is matched to blood supply

Question 21

Innervation of abdominal wall

Answer 21

Anterior (ventral) rami of T7 to L1 spinal nerves