S2 L1 Hernia's Flashcards
What is a hernia?
2 ‘types’ (clue: one more ‘complications’ than the other)?
Signs and symptoms?
A hernia is a protrusion of part of the abdominal contents beyond the normal confines of the abdominal wall
◦ Hernias occur outside the abdomen so we might say…beyond the confines of its containing cavity
Hernias that are not stuck:
◦ Fullness or swelling
◦ Gets larger when intra-abdominal pressure increases
◦ Aches
◦ Can be reducible
Hernias that are stuck (incarcerated)
◦ More painful
◦ Cannot be moved
◦ Nausea and vomiting (and other signs of bowel obstruction)
◦ Systemic problems if bowel has become ischaemic (infection → sepsis)
◦ Can’t be reducible (can’t be pushed back in)
Causes of hernia’s
Weakness in the containing cavity
o Congenitally related (we will talk about descent of the testis)
o Post surgery where wounds have not healed adequately (incisional hernia) (tissues around scar can be weaker, where the muscles have been divided)
o Normal points of weakness
Anything that increases intra-abdominal pressure (internal force pushing out through weak-points)
o Obesity
o Weightlifting
o Chronic constipation/coughing
o Pregnancy
What is a hernia?
- 3 parts
- Examples of what is each
The sac
oIs a pouch of peritoneum
o You need to understand Parietal/visceral peritoneum
Contents of the sac
o Any structure found within the abdominal cavity
o Commonly
o Loops of bowel
o Omentum
Coverings of the sac
o Consist of the layers of the abdominal wall through with the hernia has passed
o You need to know your abdominal layers
Basis of abdominal hernias…
Weaknesses in abdominal wall….
◦ Inguinal canal
◦ Femoral canal
◦ Umbilicus
◦ Previous incisions
What is the inguinal canal?
____ passage through ____ part of the ________ ____
In males, what structures pass through this canal?
Oblique, lower, abdominal wall
How do the testis descend?
- 2 key bits of anatomy
- What is this anatomy, describe it?
Processus vaginalis - pouch of the peritoneum
Gubernaculum - condensed band of mesenchyme that guides route of testes downwards to scrotum, it srhink and then the ligament secures the testes to the most inferior part of the scrotum (reduces the amount the testes can move)
Full process of the testes descending
- Processus vaginalis proceeds descent of testes
- Testes are initially retroperitoneal
- Gubernaculum guides the descent of the testes (shrinking as it is doing this)
- The gubernaculum shrinks and becomes the scrotal ligament. It secures the testes to the most inferior part of the scrotum (reduces amount testes can move)
- The processus vaginalis obliterates and becomes the tunica vaginalis
Another image showing the testes, before they descent
Normal development
- Picture showing the processus vaginalis and tunica vaginalis
Picture showing - The Processus vaginalis that doesn’t close
Creates a route from peritoneum to scrotum
Closes less than should = inguinal hernia
Structure of the inguinal canal
- Structure
- Borders
- Where does the inguinal ligament go from and to?
- Anterior wall – aponeurosis of the external oblique, reinforced by the internal oblique muscle laterally.
- Posterior wall – transversalis fascia.
- Roof – transversalis fascia, internal oblique, and transversus abdominis. Makes sense with diagram
- Floor – inguinal ligament (a ‘rolled up’ portion of the external oblique), aponeurosis), thickened medially by the lacunar ligament.
- Makes sense with diagram*
Inguinal ligament:
ASIS to pubic tubercle
Lacunar ligament
- What is this?
Reinforces the inguinal ligament
2 types of inguinal hernias
List some other types of hernias
Which hernia is most common?
– which side of the body most likely occur on?
2 types: Direct and indirect
Inguinal hernias Comprise approx: 75% of all abdominal hernias
- 50% Indirect
- M>F (7:1)
- Mainly right sided
- 25% Direct
Remaining hernias:
- 10% Umbilical
- 10% Incisional
- 3-5% Femoral
Important landmarks for Direct and Indirect Hernias
- To differentiate them?
Indirect inguinal hernias: Leaves cavity lateral to epigastric vessels
Direct inguinal hernias: Leaves cavity medial to epigastric vessels
NAME HERNIAS - WHERE THEY LEAVE THE CAVITY
Important landmarks - Hesselbachs triangle
- Boundaries
Superior/lateral: Inferior epigastric artery
Medial border: Rectus abdominus muscle
Inferior: Inguinal ligament
pic - looking inside out
Indirect Inguinal hernia
- Cause
- Characteristics about this
- What affects how ‘big’ the hernia is?
Cause:
Failure of the processus vaginalis to regress
Key points:
- Enters inguinal canal via deep ring
- Herniates to varying degree related to obliteration of processus vaginalis
- Leaves abdominal cavity laterally to inferior epigastric vessels
- Large herniation are possible - in which the peritoneal sac and its contents may transverse the entire inguinal canal, emerge through the superficial inguinal ring and reach the scrotum
Direct inguinal hernia
- Characteristics
- Does not enter the inguinal canal, but bulges through a weakness of the abdominal wall - specifically the Hesselbach’s triangle
- This hernia potentially bulges in the location of the superficial inguinal ring (as the superficial inguinal ring is a weak point)
- DOES NOT ENTER THE INGUINAL CANAL
- Leaves the abdominal cavity medially to the inferior epigastric vessels
Recap - Key Anatomical difference between the indirect inguinal hernia and direct inguinal hernia
Indirect Inguinal hernia
◦ Lateral to the Inferior Epigastric vessels
Direct Inguinal Hernia
◦ Medial to Inferior Epigastric vessels
Femoral hernia
- which gender is it more common in and why?
- Common complication and why? Why is this complication more common in femoral hernias, than in inguinal hernias?
Less common as femoral ring is smaller than inguinal ring. However, as the ring is smaller, it can more easily get stuck (incarcerated).
Incarcerated process:
Incarcerated → Irreducible → blood supply compromised → ischaemia → tissue content of hernia necroses → strangulation of hernia
Strangulation of hernia = blood supply cut off, leads to ischaemia
Femoral canal - the opening to the femoral canal is called the femoral ring
Femoral hernia
- What does this look like?
- What are the borders of the femoral canal?
Borders of femoral canal: Lacunar ligament (medial) Femoral vein (lateral)
Omphalocele
- What is this?
- Outcome?
Gastroschisis
- What is this?
- Outcome?
Umbilical hernia
- Found in what age range?
- What is this?
- Symptoms?
- Outcome?
Hernia through umbilical ring - defect in the linea alba (where the umbilical cord etc passes through). If it doesn’t close after birth = can get hernia through it
Umbilical hernia
- Found in what age range?
- What is this?
- Symptoms?
- Outcome?
Hernia through umbilical ring - defect in the linea alba (where the umbilical cord etc passes through). If it doesn’t close after birth = can get hernia through it
Para-Umbilical hernia
- Age?
- Cause? - defect where?
- Risk factors?
Defect in linea alba in the REGION of the umbilicus
Risk of strangulation as defect is small
Incisional hernia
- What is this
- Risk factors
Herniate through previous incisions
Risk factors: Previous surgery particularly emergency surgery, obese, wound infection, advancing age
Symptoms
Important terminology:
- Incarcerated
- Stangulated
Symptoms are varied
Based around what happens if loops of bowel get trapped
◦ Pain
◦ Vomiting
◦ Sepsis
Important terminology
Incarcerated
- ◦ ‘stuck’ , irreducible
Strangulated
- ◦ Blood supply is disrupted -can lead to tissue necrosis
