Inguinal Hernia

Definition | Aetiology | Pathophysiology | Risk Factors | Signs and Symptoms | Investigations | Management | Referral

Definition

An inguinal hernia occurs when abdominal contents protrude through a weakness in the inguinal canal. It is the most common type of hernia, primarily affecting men.

Aetiology

Inguinal hernias are classified into:

  • Indirect inguinal hernia: occurs through the deep inguinal ring, lateral to the inferior epigastric vessels.
  • Direct inguinal hernia: occurs through the Hesselbach's triangle, medial to the inferior epigastric vessels. Typically due to acquired weakness in the abdominal wall.

Pathophysiology

  • Increased intra-abdominal pressure pushes abdominal contents through a weakened inguinal canal.
  • Indirect hernias follow the course of the spermatic cord (males) or round ligament (females) and may extend into the scrotum.
  • Direct hernias protrude directly through the abdominal wall and are less likely to reach the scrotum.

Risk factors

  • Male gender (higher prevalence due to embryological differences).
  • Older age (loss of abdominal wall strength).
  • Congenital factors (e.g., patent processus vaginalis).
  • Increased intra-abdominal pressure from chronic coughing (e.g., COPD), constipation, or heavy lifting.
  • Obesity or significant weight loss.
  • Family history of hernias.
  • Previous abdominal surgery.

Signs and symptoms

Symptoms:

  • Groin swelling or lump, often appearing on standing or straining.
  • Discomfort or aching sensation in the groin.
  • Enlargement of the lump with coughing or lifting.
  • Symptoms of bowel obstruction (e.g., nausea, vomiting, constipation) if strangulated.

Signs:

  • Palpable mass in the inguinal region, reducible on lying down.
  • Positive cough impulse (mass enlarges when coughing).
  • Non-reducible, tender mass with skin changes suggests strangulation.

Investigations

  • Clinical examination: diagnosis is typically clinical based on history and palpation.
  • Ultrasound: first-line imaging.
  • CT scan: for complex or recurrent hernias, especially before surgery.

Management

1. Conservative Management:

  • Small, asymptomatic hernias may be monitored.
  • Advise weight management and avoiding heavy lifting.

2. Surgical Management:

  • Elective repair: for symptomatic or enlarging hernias.
  • Emergency repair: for strangulated or obstructed hernias.
  • Repair techniques you might want to know:
    • Open mesh repair (Lichtenstein technique): common for primary inguinal hernias.
    • Laparoscopic repair (TAPP/TEP): minimally invasive option, especially for bilateral or recurrent hernias.

Referral

  • Routine surgical referral: for symptomatic or progressively enlarging hernias.
  • Urgent referral: if signs of strangulation (pain, irreducibility, bowel obstruction symptoms).
GastroenterologymypanotesInguinal Hernias