S4) Abdominal Wall and Hernias

Question 1

What is a hernia?

Answer 1

A hernia is a protrusion of part of the abdominal contents beyond the normal confines of it containing cavity e.g abdominal wall

Question 2

A hernia contains 3 parts.

Identify them

Answer 2

• The sac
• Contents of the sac
• Coverings of the sac

Question 3

What is the sac of a hernia?

Answer 3

The sac is a pouch of peritoneum

Question 4

What are the contents the sac of a hernia?

Answer 4

- Contents are any structure found within the abdominal cavity

• Commonly: loops of bowel and omentum

Question 5

What does the covering of the sac of a hernia consist of?

Answer 5

Covering of sac consists of the layers of the abdominal wall through with the hernia has passed

Question 6

What generally causes abdominal hernias?

Answer 6

Weaknesses in abdominal wall

Question 7

Identify 4 points of weakness in the abdominal wall

Answer 7

• Inguinal canal
• Femoral canal
• Umbilicus
• Previous incisions

Question 8

What is the inguinal canal?

Answer 8

The inguinal canal is an oblique passage through lower part of the abdominal wall

Question 9

Distinguish between the contents of the inguinal canal in males and females

Answer 9

• Males: structures pass through from abdomen-testis
• Females: round ligament goes from Uterus-labium majus

Question 10

What is the inguinal canal made up of?

Answer 10

• Anterior and posterior walls
• Superficial and deep rings (openings)
• Roof and floor (superior and inferior walls)

Question 11

What composes the anterior wall of the inguinal canal?

Answer 11

The anterior wall is formed by the aponeurosis of the external oblique, and reinforced by the internal oblique muscle laterally

Question 12

What composes the posterior wall of the inguinal canal?

Answer 12

The posterior wall is formed by the transversalis fascia and conjoint tendon

Question 13

What composes the roof of the inguinal canal?

Answer 13

The roof is formed by the transversalis fascia, internal oblique and transversus abdominis

Question 14

What composes the floor of the inguinal canal?

Answer 14

The floor is formed by the inguinal ligament and thickened medially by the lacunar ligament

Question 15

Describe the location and formation of the deep ring

Answer 15

• The deep ring is found above the midpoint of the inguinal ligament
• The ring is created by the transversalis fascia

Question 16

The superficial ring marks the end of the inguinal canal.

Describe its location and its formation

Answer 16

• The superficial ring lies just superior to the pubic tubercle
• Formed by the evagination of the external oblique

Question 17

What are the different types of abdominal hernias that occur and how often do they occur?

Answer 17

• 75% Inguinal
• 10% Umbilical
• 10% Incisional
• 3-5% Femoral

Question 18

What two types of inguinal hernias are there?

Answer 18

• Indirect (2/3)
• Direct (1/3)

Question 19

What is an indirect inguinal hernia?

Answer 19

Indirect inguinal hernia is when the peritoneal sac enters the inguinal canal through the deep inguinal ring and passes through the canal to the superficial inguinal ring

Question 20

How can one determine the severity of the indirect inguinal hernia?

Answer 20

• The degree to which the sac herniates depends on the amount of processus vaginalis still present
• It can potentially descend into the scrotum

Question 21

Who is more likely to get an indirect inguinal hernia and how is it likely to occur?

Answer 21

• Males (7:1)
• Mainly right sided

Question 22

What is a direct inguinal hernia?

Answer 22

- Direct inguinal hernia is where the peritoneal sac enters the inguinal canal through the posterior wall of the inguinal canal

• It bulges through Hesselbach’s triangle and is in the vicinity of the superficial inguinal ring

Question 23

What are the boundaries of Hesselbach’s triangle?

Answer 23

• Lateral: inferior epigastric artery
• Medial: lateral border of rectus abdominus
• Inferior: inguinal ligament

Question 24

What is the anatomical difference between direct and indirect inguinal hernias?

Answer 24

• Indirect inguinal hernia: lateral to the inferior epigastric vessels
• Direct inguinal hernia: medial to inferior epigastric vessels

Question 25

What is a femoral hernia?

Answer 25

A femoral hernia is a hernia which occurs just below the inguinal ligament, where abdominal contents pass through the femoral canal

Question 26

How do femoral hernias present?

Answer 26

• Relatively uncommon (affects more females)
• Present as a painful lump in the groin or inner part of the upper thigh

Question 27

What is a strangulated femoral hernia?

Answer 27

A strangulated femoral hernia occurs when a femoral hernia blocks blood supply to part of the bowel

Question 28

What is an acquired infantile hernia?

Answer 28

Acquired infantile hernia is a type of umbilical hernia where the contents herniate through weakness in scar of umbilicus

Question 29

What is an acquired adult hernia?

Answer 29

An acquired adult hernia is a type of umbilical hernia where the contents go through the linea alba in region of umbilicus

Question 30

How do epigastric hernias occur?

Answer 30

• Epigastric hernias occurs through the linea alba between xiphoid process→umbilicus
• They usually starts with small hernia (extra-peritoneal fat)
• Chronic straining forces more fat out which eventually pulls peritoneum through

Question 31

What symptoms can one expect with abdominal wall hernias?

Answer 31

• Varied symptoms as it’s based on what happens if loops of bowel get trapped
• Commonly: pain, vomiting, sepsis