Session 4 - Abdominal Hernias Flashcards
What is a hernia?
A protrusion of part of the abdominal contents beyond the normal confines of the abdominal wall.
A hernia consists of what 3 parts?
- The sac - a pouch of peritoneum
- Contents of the sac - a structure found within the abdominal cavity, commonly loops of bowel or omentum
- Covering of the sac - consists of the layers of the abdominal wall through which the hernia has passed
Abdominal hernias protrude through weaknesses in the abdominal wall. Give examples of possible weaknesses.
Inguinal canal
Femoral canal
Umbilicus
Previous incisions (scar tissue itself very strong but tissue surrounding scar is not)
What are the boundaries of the inguinal canal?
Anterior wall - aponeurosis of the external oblique (reinforced by internal oblique laterally)
Posterior wall - transversalis fascia
Roof - transversalis fascia, internal oblique and transversus abdominis
Floor - inguinal ligament (reinforced medially by the lacunae ligament)
What is the inguinal ligament?
Runs from the anterior superior iliac spine to the pubic tubercle. Is formed from the external abdominal oblique aponeurosis and is continuous with the fascia lata of the thigh. Forms the floor of the inguinal canal.
What is a reducible hernia?
One which can be pushed back into the abdomen by putting manual pressure on it.
What is an irreducible/incarcerated hernia?
One which cannot be pushed back into the abdomen by applying manual pressure.
Irreducible hernia can be further classified into what two categories?
Obstructed hernia
Strangulated hernia
What is a obstructed hernia?
Irreducible hernia in which the lumen of the herniated part of intestine is obstructed.
What is a strangulated hernia?
An irreducible hernia in which the blood supply of the hernia contents is cut off, this leading to ischaemia.
What is a pantaloon hernia?
When a patient suffers a direct and indirect inguinal hernia on the same side simultaneously.
What are the borders of Hesselbach’s triangle?
Superior - inferior epigastric artery
Medial - rectus abdominis muscle
Inferior - inguinal ligament
Where are direct and indirect inguinal hernias found in relation to the epigastric vessels?
Direct inguinal hernia - medial to inferior epigastric vessels
Indirect inguinal hernia - lateral to the inferior epigastric vessels
What are the inferior epigastric vessels?
Inferior epigastric artery
Inferior epigastric vein
What is a direct inguinal hernia?
Hernia protruding through a weakness in transversalis fascia within Hesselbach’s triangle. May exit via the superficial inguinal ring. Not capable of extending into the scrotum.
What is an indirect inguinal hernia?
Hernia passing though the deep inguinal ring, then the inguinal canal and the superficial inguinal ring. Can potentially descend into the scrotum.
Indirect inguinal hernias are the result of what developmental defect?
Failure of the processus vaginalis to obliterate
Are inguinal hernia more common in males or females?
Males
Are femoral hernias more common in males or females?
Females
Describe the route of a femoral hernia.
In through femoral ring, down the femoral canal, out through the saphenous opening.
What are the two type of congenital umbilical hernia?
Omphalocele
Gastrochisis
What is an acquired infantile umbilical hernia?
Hernia where abdominal contents protrudes through a weakness in scar of umbilicus.
What is an acquired adult umbilical hernia?
Hernia which protrudes through an area in the region of the umbilicus called the linea alba.
What is the difference between an omphalocele and gastrochisis?
Omphalocele - abdominal viscera contained within a parietal peritoneum and amniotic membranous sac.
Gastrochisis - abdominal viscera not covered by a membrane
