Incisional and epigastric hernia

Question 1

How do incisonal hernias occur?

What is the incidence of incisional hernias - how common and how often after surgery?

Answer 1

• An incisional hernia occurs through a defect in the scar from previous abdominal surgery.
• It is most common with midline laparotomy scars.
• Incisional hernias make up 10% of the hernias seen and 1% of abdominal incisions are followed by hernias.

Question 2

What are the risk factors for incisional hernias?

Answer 2

Pre-operative factors:

• old age
• poor nutrition (protein and Vitamin C deficiency)
• sepsis
• uraemia
• jaundice
• obesity
• steroids all decrease wound healing

During the operation:

• Vertical incision
• knots that are too loose/too tight
• presence of drains make hernias more likely
• (poor technique, weak suture material)

Post-operative factors:

• post operative ileus
• coughing
• distension
• wound infection
• haematoma
• obesity
• anything that increases intra-abdominal pressure

Question 3

Describe the symptoms of incisional hernias

Answer 3

Many incisional hernias will be asymptomatic (though patients may present with a lump), watch for intestinal obstruction.

Although may be:

• bulge in the scar and local discomfort
• subacute bowel obstruction is common as the hernia enlarges
• There is a wide neck, so strangulation is generally uncommon, however as contents accumulate then adhesions often develop so the hernia becomes irreducible

Question 4

Describe the findings on physical examination of patients with ventral hernias including mass and tenderness in those with incarcerated hernias and estimation of the size of the defect in patients with reducible hernias

Answer 4

A midline ventral hernia may be seen as an elongated gap between the rectus muscles in elderly, wasted patients (divarication of the recti).

The size of the defect may be estimated by reducing the hernia and then feeling for the borders.

Question 5

What are the common presenting features of epigastric herniae?

Answer 5

• One or more small protrusions though the linea alba above the umbilicus, usually containing only extra peritoneal fat.
• Over 75% are asymptomatic, although some are very painful, with the pain worse on physical exertion or after meals

Question 6

What is divarication of the rectus abdominus muscle?

Answer 6

• Divarication of the rectus muscle is where the rectus muscles do not meet in the midline at the linea alba, and thus spilt apart when the patient flexes the abdominal muscle.
• It is common but benign

Increased IAP will cause the left and right muscles to separate.

Question 7

How can you distinguish an epigastric hernia from a divarication of the rectus abdominus muscle

Answer 7

• Epigastric hernias may occur anywhere between the xiphoid process and the umbilicus.
• Divarication of the rectus muscles occurs along the linea alba.

When the patient does a sit-up, the rectus muscles are the only muscles being used and so a midline bulge and muscle separation will present in both epigastric hernia and divarication.

When the patient coughs, all abdominal muscles are used, so the muscle separation and midline bulge will only occur in the hernia – the divarication is not as severe, as many muscle groups are being used – the rectus muscles are not taking all responsibility for the action and aren’t under maximum strain.