GI S3 - Anterior Abdominal Wall Anatomy and Hernias Flashcards
What are the borders of the inguinal triangle?
Inferiolateral: the inguinal ligament
Medial: the lateral border of rectus abdominus
Superiolateral: the inferior epigastric artery
From innermost to outermost, what are the muscle layers of the anterior abdominal wall?
Transversus abdominus Rectus abdominus Abdominus internus (internal oblique) Abdominus externus (external oblique)
Where are the inguinal rings?
Deep: is a hole in the fascia of transversus abdominus superior to the crossing of the inguinal ligament and the inferior epigastric artery.
Superficial: a hole in the Aponeurosis of the external oblique muscle. Medial to rectus abdominus and superior to the inguinal ligament.
What is the accurate line?
Inferior to this line, rectus abdominus passes beneath transversus abdominus.
What is the clinical significance of the inguinal canal?
Is a route for small intestine herniation, specifically a direct inguinal hernia.
Describe an inguinal hernia
Most common type of hernia (75%) of cases
When small intestine escapes abdominal cavity via one or more of the inguinal rings
Present as a bulge in the groin area
Direct or indirect
Usually not treated due to minimal in recreation risk
What would make a hernia “reducible”?
If the hernia can be pushed back through the abdominal wall to its correct location without coming back out, it’s reducible
What would make a hernia “incarcerated”?
If the hernia can’t be pushed back through the abdominal wall to its correct location without coming back out, it’s incarcerated.
What would make a hernia “strangulated”?
When blood supply to herniated tissue is cut off and the tissue starts to become ischaemic and necrosed.
Describe indirect inguinal hernias
Most common type of groin hernia
Passes through both superficial and deep inguinal rings
Due to a failure of the processus vaginalis to close (aka a patency)
Hernia sac begins lateral to the inferior epigastric vessels
Describe direct inguinal hernias
Rare in women
Likelihood increases with age, family history and obesity
Passes through transversal is fascia and the superficial inguinal ring (NOT the deep)
So hernia sac begins medial to the inferior epigastric vessels
Describe umbilical hernias
Most commonly seen in children/neonates
Usually resolves itself so surgery isn’t performed until the child is 5/6
Low complication risk
Congenital weakness
Occasionally seen in adults (more often women) with increased intra-abdominal pressure
Describe femoral hernias
Rare but more common in women
Passes through femoral canal
High strangulation risk so surgery recommended
Rounded shape and bulk of hernia below inguinal ligament
What are the borders of the femoral canal?
Posterior: pectineus
Anterior: inguinal ligament
Lateral: femoral vein
Medial: lacunar ligament
Describe incisional hernias
Due to incompletely healed surgical wounds causing a weakness in the anterior abdominal wall
Best results if repaired laparoscopically with a mesh
