Hernias (femoral, inguinal, miscellaneous)

Question 1

Define hernia.

Answer 1

The protrusion of a viscus or part of a viscus through a defect of the walls of its containing cavity into an abnormal position.

Question 2

Define femoral hernia.

Answer 2

Intestinal projection across femoral canal associated with femoral aretry, vein; below inguinal ligament and lateral to pubic tubercle.

Question 3

What are the borders of the femoral canal?

Answer 3

• Medial border – lacunar ligament (and pubic bone)
• Lateral border – femoral vein (and ilipsoas)
• Anterior border – inguinal ligament.
• Posterior border – pectineal ligament, superior ramus of the pubic bone, and the pectineus muscle

The neck of the hernia is felt inferior and lateral to the pubic tubercle (inguinal hernias are superior and medial to this point).

Question 4

What is the epidemiology of hernias?

Answer 4

Females get more femoral

Males get more inguinal

INDIRECT hernias are 5 times more common than direct hernias (this is due to persistence of the processus vaginali

Question 5

What is the aetiology of femoral hernias?

Answer 5

• Congenital, acquired
• Weakness/abnormal fasical opening in abdominal wall
• Usually includes properitoneal fat/omentum edge/small bowel loop

Question 6

What are the risk factors for a femoral hernia?

Answer 6

• Biologically - female - they have wider pelvis
• Congenital disorder (embryological development –> processus vaginalis obliteration failure)
• FH
• Obesity
• Pregnancy
• Frequent heavy lifting

Question 7

What are the signs and symptoms of a femoral hernia?

Answer 7

• Asymptomatic (commonly)
• Can manifest as intestinal obstruction symptoms:
  
  • Bulging mass, pain, discomfort
  • Supine: may resolve
• Valsalva maneouvre (coughing/straining) worsens
• Abdominal contents enter hernia –> may precipitate intestinal obstruction -
  
  • Most common cause worldwide.
  • Incarcerated/strangulated causes severe abdominal pain, tenderness, erythema, fever, nausea, vomiting

Question 8

What investigations would you do for femoral hernias? What would they show?

Answer 8

Usually clinical diagnosis and no imaging needed.

USS - variable echogenicity of tissues. Movement of intra-abdominal structures in an inferior direction through the femoral canal.

CT - Visualisation of characteristic funnel-shaped neck; protrusion through femoral ring

Usually hernias are diagnosed clinically by physical examination but imaging may be necessary in obese patients.

Question 9

What is the management of femoral hernias?

Answer 9

Surgery:

• Repair - open/laproscopic (case dependent)
• Early/elective repair - uncomplicated/asymptomatic hernia
• Urgent repair - complicated hernia (may require bowel resection)

Femoral hernias, usually need operative intervention. This should ideally an elective (non-emergency) procedure. However, because of the high incidence of complications, femoral hernias often need emergency surgery

Question 10

What are the complications of hernias?

Answer 10

• Irreducible: contents cannot be pushed back into place
• Strangulated hernia = vascular compromise, surgical emergency
• Obstructed hernia = obstruction of lumen within hernia e.g. bowel obstruction
• Incarcerated hernia = irreducible; contents of the hernial sac are stuck inside by adhesions

Care must be taken with reduction as it is possible to push an incarcerated hernia back into the abdominal cavity, giving the initial appearance of successful reduction.

Question 11

What is the prognosis with femoral hernias?

Answer 11

• Usually depends on the extent of bowel compromised
• Patients go home the same day as surgery

Question 12

What is the management of hernias?

Answer 12

Conservative -

• Do nothing
• Wear a trus

Surgical

• Herniotomy is ligation and excision of the sac
• Herniorrhaphy is repair of the hernial defect.
• Mesh repair - open or laproscopic

Question 13

What are differentials for a femoral hernia?

Answer 13

1 Inguinal hernia.

2 Saphena varix.

3 An enlarged Cloquet’s node

4 Lipoma.

5 Femoral aneurysm.

6 Psoas abscess.

Question 14

What are the walls of the inguinal canal?

Answer 14

Floor: Inguinal ligament and lacunar ligament medially;

Roof: Fibres of transversalis, internal oblique;

Anterior: External oblique aponeurosis + internal oblique for the lateral ⅓;

Posterior: Laterally, transversalis fascia; medially, conjoint tendon.

Question 15

Describe direct inguinal hernia.

Answer 15

Peritoneal sac projects directly through the inguinal triangle (aka Hesselbach’s triangle)

Projects medially to inferior epigastric vessels lateral to rectus abdomini and pierces the peritoneum. It is covered by external spermatic fascia.

Question 16

Describe indirect inguinal hernias.

Answer 16

• Most common type of hernia
• Intestinal projection through internal inguinal ring
  
  • Location - spermatic cord (in amale), round ligament (in female) exit the abdomen
  • Testicular descent path - covered by three layers of spermatic fascia: external spermatic fascia (external oblique continuation), cremasteric muscle fascia, internal spermatic fascia (internal oblique fascia continuation)

Question 17

What is the aetiology of indirect inguinal hernias?

Answer 17

Processus vaginalis closure failure - internal inguinal ring and processus vaginalis obliteration failure

Question 18

What is the aetiology of direct inguinal hernias? What is the pathophysiology?

Answer 18

ALWAYS acquired therefore unusual below age 25

A direct inguinal hernia occurs because of degeneration and fatty changes in the aponeurosis of the transversalis fascia that constitutes the inguinal floor or posterior wall in the Hesselbach triangle area.

Most direct hernias do not have a true peritoneal lining and do not contain bowel, but mainly preperitoneal fat, and occasionally bladder.

Question 19

With which type of inguinal hernia is strangulation more common?

Answer 19

INDIRECT - strangulation more common because there is a sharply defined ring which might have a narrow neck

DIRECT - less common to get strangulation as structural defect in a direct hernia is usually a diffuse weakness and stretching of the inguinal floor tissues

Question 20

How common are inguinal hernias?

Answer 20

• Indirect is 5x more common than direct and 7x more common in males due to the persistence of the processus vaginalis during testicular descent.
• Lifetime risk in women is 3% and 27% for men
• Inguinal hernia is bilateral in 20% of affected adults
• FH associated with increased
• In children, the vast majority of inguinal hernias are indirect.

Question 21

What are the risk factors for inguinal hernia?

Answer 21

• Male sex
• Old age
• FH
• AAA - persistently increased leukocytosis and reduced anti-proteolytic activity
• Smoking - decreased alpha-1 antitrypsin and elevated serum
• Chronic bronchitis or emphysema - chronic cough increases IAP
• Previous surgery
• Defective transversalis fascia
• Prematurity - up to a third of male babies born weighing less than 1500g require hernia operation by age 8yrs
• Marfan syndrome
• Ehlers-Danlos syndrome
• Lathyrism - neurotoxic disease caused by ingestion of certain types of legumes

Weak: heavy lifting, pregnancy, ascites, BPH, urethral stricture.

Question 22

Which inguinal hernia:

Can form a hydrocele, may precipitate intestinal obstructio and is the most common cause of hernia worldwide?

Answer 22

Indirect inguinal

Question 23

Signs and symptoms of an inguinal hernia?

Answer 23

• Groin discomfort or pain with bulge - (often described as dull, heaviness, dragging, and sometimes burning)
• Groin mass
• Abdominal discomfort or pain - poorly localised pain, indicative of stretch in the hernia sac
• Acute abdomen - tender, distended abdomen with absent bowel sounds = stangulated hernia
• Nausea and vomiting
• Constipation

Question 24

What investigations would you do for inguinal hernias?

Answer 24

NB: usually clinical diagnosis

US -

• Direct inguinal hernia - variable echogenicity of tissue; movement of intra-abdominal structures in an anterior direction through the Hesselbach triangle
• Indirect inguinal hernia - visualisation through abdominal wall in biologically-female individuals

CT:

• Direct inguinal hernia - visualisation of a protrusion with compression inguinal canal contents; inguinal canal pushed into a semicircle of tissue that resembles a moon crescent
• Indirect inguinal hernia - identifies occult hernia/complications; hernia neck visualised superloateral to the inferior epigastric vessels

Question 25

What is the management of inguinal hernias?

Answer 25

• Open/laparoscopic (case-dependent)
• Elective repair - symptomatic hernias
• Direct inguinal hernia (asymptomatic) - monitor, surgical repair preferred

Question 26

Name 5 different types of hernia.

Answer 26

Question 27

Describe paraumblilical hernias.

Answer 27

• occur just above or below the umbilicus.
• Risk factors are obesity and ascites.
• Omentum or bowel herniates through the defect.
• Surgery involves repair of the rectus sheath (Mayo repair).

Question 28

Where does an epigastric hernia pass through?

Answer 28

Linea alba above umbilicus

Question 29

Why do incisional hernias occur?

Answer 29

• Breakdown of muscle closure after surgery (11–20%).
• If obese, repair is not easy.
• Mesh repair has ↓recurrence but ↑infection over sutures

Question 30

What is the location of spigelian hernias?

Answer 30

Occur through the linea semilunaris at the lateral edge of the rectus sheath, below and lateral to the umbilicus.

Question 31

What is an obturator hernia?

Answer 31

occur through the obturator canal. Typically there is pain along the medial side of the thigh in a thin woman.

Question 32

What is a sciatic hernia?

Answer 32

Pass through the lesser sciatic foramen (a way through various pelvic ligaments). gi obstruction + a gluteal mass suggests this rare possibility.

Question 33

What is a sliding hernia?

Answer 33

Contain a partially extraperitoneal structure (eg caecum on the right, sigmoid colon on the left). The sac does not completely surround the contents.

Question 34

Where do lumbar hernias occur?

Answer 34

Occur through the inferior or superior lumbar triangles in the posterior abdominal wall.

Question 35

What is the most common type of paediatric hernia? Why do they occur? What is the treatment?

Answer 35

Umbilical hernias: (3% of live births). Are a result of a persistent defect in the transversalis fascia. Surgical repair rarely needed as most resolve by the age of 3

Question 36

What is a common type of male paediatric hernia?

Answer 36

Indirect inguinal hernias (~4% of all ♂ infants due to patent processus vaginalis—prematurity is a risk factor;

Uncommon in ♀ infants—consider testicular feminization.

Surgical repair is required.

Question 37

What is the name for the paediatric condition where abdominal contents are found outside the abdomen, covered in a three-layer membrane consisting of peritoneum, Wharton’s jelly, and amnion?

Answer 37

Exomphalos

Question 38

Is exomphalos a surgical emergency?

Answer 38

Surgical repair less urgent because the bowel is protected by three membranes.

Question 39

What is gastroschisis?

Answer 39

Paediatric hernia - Protrusion of the abdominal contents through a defect in the anterior abdominal wall to the right of the umbilicus. Prompt surgical repair required.