Lecture 7: Hernias

Question 1

What is a hernia?

Answer 1

Protrusion of part of the abdominal contents, beyonf the normal confines of the abdominal wall

Question 2

What are the 3 parts of a hernia?

Answer 2

1. Contents of the sac (e.g. small intestine)
2. The sac (peritoneum)
3. Covering of the sac (e.g. layers of abdominal wall)

Question 3

What are some signs and symptoms of a hernia?

Answer 3

• fullness
• swelling
• increase in size when intra-abdominal pressure increases (coughing/lighting weights)
• discomfort

Question 4

What is it called when a hernia gets stuck?

Answer 4

Incarcerated

• pain
• fixed in place (before you could reduce the hernia into cavity)
• if bowel is stuck you may feel sick/vomit (bowel obstrusion)
• bowel could become ischaemic and die : necrotic bowel: peritonitis

Question 5

What are some common abdominal wall hernias?

Answer 5

1. Inguinal hernias (75%)
2. Femoral hernias (3-5%)
3. Umbilical hernias (10%)
4. Incisional hernias (10%) (through previous incisions)

Question 6

What is the inguinal canal?

Answer 6

Oblique passage through the lower part of the abdominal wall
(Male: abdomen > scrotum)
(Female: uterus > labium majus)
Deep ring in middle of the inguinal ligament, and its exit point if just above the pubic tubercle.

Question 7

In which sex are inguinal hernias more common?

Answer 7

Male

right side of body moreso than the left

Question 8

How does the testes descend, and how are hernias common if something goes wrong?

Answer 8

-processus vaginalis proceeds the decent of the testis
-testes are initially retroperitoneal, and are guided down by the gubernaculum which condenses
(both structures head downwards towards the developing scrotum)
-processus vaginalis is obliterated from the peritoneal cavity and is now called the tunica vaginalis
-the remnants of the gubernaculum is called the scrotal ligament and it anchors the testis in place
-if processus vaginalis doesn’t obliterate, fluid can collect in the peritoneal cavity or hernias can travel through it

Question 9

What is the anterior outpouching of the peritoneum called?

Answer 9

Processus vaginalis

Question 10

What forms the inguinal ligament?

Answer 10

Anterior wall: aponeurosis of external oblique
Floor: thickened inferior roll of external oblique aponeurosis (inguinal ligament)
Roof: arching fibres of the internal oblique/transversus abdominus
Posterior wall: transversalis fascia

Question 11

What is the conjoint tendon?

Answer 11

The transversus abdominus and the internal oblique combine and insert into the superior ramus of the pubis

Question 12

What is the entrance/exit to the inguinal ligament?

Answer 12

Deep ring (entrance)- comes through transversalis fascia
Superficial ring (exit)- comes through aponeurosis of external oblique

Question 13

What is the medial portion of the inguinal ligament called?

Answer 13

Lacunar ligament: triangular extension of inguinal ligament which inserts into the pectineal line

Question 14

What are the two types of inguinal hernia?

Answer 14

Direct/indirect inguinal hernia

indirect are more common

Question 15

What is an inguinal indirect hernia?

Answer 15

Part of the abdominal viscera goes into the inguinal canal (if the processus vaginalis fails to obliterate you can get the hernia travelling through the canal and inot the scrotum)
-abdominal viscera enters iguinal canal via deep ring herniating to a varying degree (related to obliteration of the processus vaginalis)

Question 16

What vessels lie near the deep ring?

Answer 16

Deep ring lies lateral to the inferior epigastric vessels

Question 17

What is an inguinal direct hernia?

Answer 17

Does not enter inguinal canal
-bulges through weakness in abdominal wall called Hesselbach’s triangle
(sometimes looks like it is bulging through the superficial ring)
Can still end up as scrotal hernias
-lie medial to inferior epigastric vessels

Question 18

What are the borders of Hesselbach’s triangle?

Answer 18

Medially: border of rectus abdominus muscle
Superolaterally: epigastric vessels
Inferiorly: inguinal ligament

Question 19

In which sex are femoral hernias more common in?

Answer 19

Females because entrance to femoral canal is wider in women

Question 20

What is a femoral hernia?

Answer 20

Where the abdominal viscera enters the femoral canal via the femoral ring

• it can pop out of the saphenous opening forming a lump
• inferior to inguinal ligament

Question 21

What features lie around the femoral canal?

Answer 21

Femoral vein laterally

Lacunar ligament medially

Question 22

Why are femoral hernias rare?

Answer 22

Because the femoral ring is quite small so the chances of bowel getting stuck in it is rare
-but when they do, there is a greater chance of the hernia being incarcerated
(swelling develops when it becomes incarcerated, and venous pressure is lower than arterial pressure, you get blood going in and not out of the structure: eventually the pressure in artery is too high and blood supply is comprimised so it becomes ischaemic > necrotic- STRANGULATED HERNIA)

Question 23

In whom are umbilical hernias more common?

Answer 23

Common in infants (most resolve spontaneously)

-more common in premature babies and babies of african descent, or babies with a low birth weight

Question 24

What is an umbilical hernia?

Answer 24

Hernia through umbilical ring

• umbilical ring is a defect in the linea alba (should normally close after birth)
• unusual to have incarceration/strangulation

Question 25

What is a para-umbilical hernia?

Answer 25

Affects adults
Hernia through defect in linea alba in the region of the umbilicus
-affects females more
-obesity is a risk factor

Question 26

What is the difference between incarceration and strangulation?

Answer 26

Only that incarceration can cause strangulation, but strangulation can’t cause incarceration

Question 27

What is an incisional hernia?

Answer 27

Hernias that comes through previous incision

• emergency surgery doubles the risk than a planned surgery
• obesity is a risk factor
• increased risk if incision is in midline

Question 28

What are some common incisions used for abdominal surgery?

Answer 28

Midline incision: avoids umbilicus, varying length, through linea alba, good as it is relatively avascular, uncomfy post-op
Para-median incision: parallel to midline,can damage nerves/structures, not usually used
Gridiron: appendicectomy, 2/3 from umbilicus to asis
Pfannenstiel: curvy incision made in skin and subcutaneous fat, used in obstetrics and urology
Kocher: parallel to subcostal margin, access to liver, used for cholecystectomy (remove gallbladder)