Hernias Flashcards
What is visceral pain?
- Pain that results from visceral stretching, inflammation or ischaemia
- Pain is diffuse and midline
- Nausea, vomiting, sweating
- Very common presentation
- Difficult to diagnose
What is a hernia?
- A protrusion of part of the abdominal contents beyond the normal confines of the abdominal cavity
What are the symptoms of a hernia that isn’t stuck?
- Fullness or swelling
- Gets larger when intra-abdominal pressure increases
- Aches
What are the symptoms of a hernia that is incarcerated?
- Pain
- Cannot be moved
- Nausea and vomiting
- Systemic problems if bowel has become ischaemic
What are the causes of hernia?
- Weakness in containing cavity
- Can be congenital, post-surgery (incisional), normal points of weakness
- Due to things that increase intra-abdominal pressure e.g. obesity, weightlifting,
What forms the sac of a hernia?
- A pouch of peritoneum
What are the contents of the sac of a hernia?
- Any structure found within the abdominal cavity e.g. loops of bowel, omentum
What are the coverings of the coverings of the sac of a hernia?
- Consists of the layers of the abdominal wall through which the hernia has passed
Where are the naturally occurring weaknesses in the abdominal wall?
- Inguinal canal
- Femoral canal
- Umbilicus
- Previous incisions
What is the inguinal canal?
- Oblique passage through lower part of abdominal wall
- Very short
- In men structures pass through from abdomen to testis (acts as a passageway from inside peritoneal cavity to scrotum)
- In women round ligament goes from uterus to labium majus
What congenital abnormality makes males more susceptible to hernias?
- Processus vaginalis is an outpouching of peritoneum
- During normal development, this obliterates
- If Processus vaginalis doesn’t obliterate, a pathway is created from inside peritoneal cavity to external scrotum, through which fluid can pass.
What forms the inguinal ligament?
- Inguinal ligament is the rolled and thickened edge at the bottom of the external oblique
What is the conjoint tendon?
- Where the internal oblique and transverse abdominus have fused together.
What forms the floor of the inguinal canal?
- Inguinal ligament
- Lacunar ligament (medially)
What forms the roof of the inguinal canal?
- Internal oblique/transverse abdominus
- Muscular arches and aponeurosis
What forms the posterior wall of the inguinal canal?
- Transversalis fascia
- Conjoint tendon medially reinforces posterior wall
What forms the entrance to the inguinal canal?
- Deep ring
What forms the anterior wall of the inguinal canal?
- Aponeurosis of external oblique
What forms the exit of the inguinal canal?
- Superficial ring
- Exit to scrotum or labia majora
Describe the properties of inguinal hernias
- 75% of hernias are inguinal
- 50% indirect, 25% direct
- M>F
- Mainly right sided
Which type of hernia often strangulates?
- Femoral (3-5% of hernias)
Where would you say the location of a hernia is?
- Where is begins, not where it shows up
- This is because hernias can travel quite a long distance away from their origin
Which structures form the borders of Hesselbach’s triangle?
- Rectus abdominis muscle
- Inguinal ligament
- Inferior epigastric vessels
What pathway is taken by an indirect inguinal hernia?
- Passes through deep inguinal ring
- Through inguinal canal
- Exits through superficial inguinal ring
- Can potentially descend into scrotum if processus vaginalis wasn’t obliterated
What is the relationship between Hesselbach’s triangle and the inguinal canal?
- Superficial inguinal ring sits in the centre of Hesselbach’s triangle
What pathway is taken by a direct inguinal hernia?
- Bulges through Hesselbach’s triangle
- Doesn’t travel through inguinal canal
- Generally emerges in the vicinity of the superficial inguinal ring
What is the anatomical difference between indirect inguinal hernias and direct inguinal hernias?
- Indirect inguinal hernias arise lateral to the inferior epigastric vessels
- Direct inguinal hernias arise medial to the inferior epigastric vessels
Outline the properties of femoral hernias
- More common in females
- Can easily get incarcerated
- Hernia comes down femoral canal and exits at saphenous opening
Outline the properties of an umbilical hernia
- 10% of all hernias are umbilical
- Commonly found in infants
- Not usually painful
- 80-90% self-resolve by age 3
What is a para-umbilical hernia?
- Hernia goes through defect in linea alba in region of umbilicus
- F>M
- Obesity
- Risk of strangulation because defect is often small
What does it mean if a hernia is incarcerated?
- Hernia is stuck, irredducible
What does it mean if a hernia is strangulated?
- Blood supply is disrupted
- Can lead to tissue necrosis
