Hernias

Question 1

Define a hernia

Answer 1

Protrusion of part of the abdominal contents beyond the normal confines of the abdominal wall, consisting of sac, contents and covering

Question 2

What is the inguinal canal?

Answer 2

An oblique passage through the lower abdominal wall, extending inferiorly and medially. Made up anterolateral abdominal muscles.

Question 3

Describe the role of the inguinal canal in male genitalia development

Answer 3

Inguinal canal is pathway for testes to leave abdominal cavity and enter scrotum.
Canal is flanked by abdominal muscles and peritoneum, which out-pockets to form processus vaginalis, which usually degenerates, but if it persists can result in indirect inguinal hernia

Question 4

What are the usual contents of a hernia?

Answer 4

Loops of bowel

Omentum

Question 5

How does the inguinal canal differ between men and women?

Answer 5

Males- Structures pass from abdomen to testis

Females - Round ligament goes from uterus to labium majus

Question 6

What is the gubernaculum?

Answer 6

Condensed band of mesenchyme that links inferior gonads to labioscrotal swelling

Question 7

What are consequences of a partial/not obliterated processus vaginalis?

Answer 7

Partial - inguinal hernia

No obliteration - Scrotal hernia

Question 8

What are the boundaries of the inguinal canal?

Answer 8

Anterior wall- Aponeurosis of external oblique and reinforced by internal oblique laterally
Posterior wall - transversalis fascia and conjoint tendon, medially
Roof- Transversalis fascia, internal oblique, transversus abdominus
Floor - Aponeurosis of external oblique (inguinal ligament) and thickened medially by lacunar ligament

Question 9

What is the mid-inguinal point?

Answer 9

Halfway between pubic symphysis and anterior superior iliac spine
Femoral artery crosses into lower limb here

Question 10

What is the midpoint of the inguinal ligament?

Answer 10

Midpoint of the inguinal ligament as it runs from the pubic tubercle to anterior superior iliac spine
Opening to inguinal canal is just above it

Question 11

What defence mechanisms does the body have against hernias?

Answer 11

Walls of inguinal canal collapsed around their contents, preventing other structures from entering the canal
When intra-abdominal pressure increases, muscles of anterior and posterior wall contract and clamp down on the canal

Question 12

Where are the deep and superficial rings found?

Answer 12

Deep - above midpoint of inguinal ligament

Superficial - superior to pubic tubercles

Question 13

What is contained in the inguinal canal?

Answer 13

Men - Spermatic cord, to supply and drain testes

Women - Round ligament of uterus

Question 14

What is an indirect inguinal hernia?

Answer 14

Peritoneal sac enters inguinal canal via deep ring, acquiring the same coverings as the contents of the canal
Degree of herniation depends on the amount of processus vaginalis present, so has a congenital origin IC
Lateral to inferior epigastric vessels

Question 15

What is a direct inguinal hernia?

Answer 15

Peritoneal sac enters inguinal canal through posterior wall of inguinal canal due to acquired weakening of abdominal muscles in Hesselbach’s triangle DA
Medial to inferior epigastric vessels

Question 16

What are the coverings of direct hernias when they exit the abdominal cavity?

Answer 16

Peritoneum

Transversalis fascia

Question 17

What are the coverings of indirect hernias when they exit the abdominal cavity?

Answer 17

Peritoneum of persistant processus vaginalis
External spermatic fascia
Cremaster muscle and fascia
Internal spermatic fascia

Question 18

Why are femoral hernias more common in women?

Answer 18

Wider angle of pelvis, so entrance to femoral canal via the femoral ring is wider, more likely something will go into it

Question 19

What is an incarcerated hernia?

Answer 19

A hernia that gets stuck, is irreducible

Question 20

What is a strangulated hernia?

Answer 20

Where blood supply is disrupted, leading to tissue necrosis

Question 21

Why do femoral and inguinal hernias strangulate?

Answer 21

Have narrow necks

Question 22

What is an umbilical hernia?

Answer 22

Congenital:
Omphalocele - a midgut hernia that doesn’t return, contents herniate into umbilical cord
Has a peritoneal covering
Acquired:
Contents herniate through weakness in scar of umbilicus
Adult:
Contents hernaite through linea alba in region of umbilicus

Question 23

What is an epigastric hernia?

Answer 23

Contents herniate through linea alba, between xiphoid process and umbilicus
Chronic straining forces more fat out, eventually pulling peritoneum through

Question 24

What are the symptoms of a hernia?

Answer 24

Loops of bowel trapped so:
Pain
Vomiting
Sepsis