A hernia is a weakness or opening in the abdominal wall, that often results in bulging out of fat or an organ such as intestine, which then occupies space under the skin.
The opening in the abdominal wall through which the fat or organs protrude is called the Hernia defect.
Hernia can affect anybody – going by statistics one-in-ten of us will have hernia at some point in our lives. It is found in both sexes, can occur at any age and sometimes infants may be born with it.
Surgery for hernia is one of the most commonly performed operations worldwide with millions of cases being treated every year.

Understanding the mechanism of Hernia

To choose the right treatment, it is of utmost importance that you understand what exactly hernia is. The abdominal wall which consists of the abdominal muscles and tendons, holds the abdominal contents in place. These abdominal contents consist of fat and various organs especially the intestines. The abdominal wall envelopes these contents like a corset. If there is any weakness or opening in this wall, the corset like effect is lost and it gives way to the abdominal contents causing them to protrude through the defect. This bulging of the fat/organs is what we call the hernia, which is usually visible as a swelling under the skin. This mechanism is similar to what happens with a bulge in a damaged tyre, where the inner tube, normally contained by the hard rubber of the tire extends out through a thin or weakened space.

Why do Hernias occur?

Any condition that increases the pressure of the abdominal cavity over a prolonged period of time may become a cause for hernia eg. Obesity, chronic cough, heavy lifting, chronic constipation leading to straining during bowel movement.
Family history of hernia makes one more likely to get it.
Some hernias may be present at birth
Idiopathic, which means the cause is not known.

Symptoms of Hernia

  • A hernia may first appear as a new lump or bulge in the groin or in the abdominal area. There may be an associated dull ache but usually it is not painful on touch. The lump increases in size on standing, coughing and may be pushed back/disappear on lying down.
  • A small painless hernia if left untreated, usually increases in size.
  • Occasionally, the hernia may become irreducible i.e. it cannot return to the abdominal cavity on lying down or with manual pushing. At this stage it also becomes painful.
  • Sometimes the loop of bowel that has herniated becomes obstructed. This can cause extreme pain, nausea, vomiting, constipation and needs immediate treatment.
  • At times the hernia becomes 'strangulated' (explained further below) in which the person appears ill with/without fever, nausea, vomiting and extreme pain even to touch. This condition is life threatening and thus a surgical emergency.

What is a strangulated Hernia?

If a loop of intestine or omentum becomes trapped in the weak point in the abdominal wall (hernia defect) through which it has herniated, it can obstruct the bowel leading to severe pain, nausea, vomiting and inability to have a bowel movement or pass gas. This is called an Incarcerated hernia. An Incarcerated hernia may cut off blood supply to the trapped intestine. This condition is called Strangulation and it can cause rapid death of that part of the bowel tissue. Any dead tissue within the body can turn extremely hostile very quickly and start releasing toxins in the blood stream which causes Septicaemia (blood poisoning) and in turn death, if not treated immediately and aggressively. Strangulation most commonly occurs with the smaller hernias, as the larger ones tend to slide in and out easily and are at a lesser risk of being clamped shut by the muscle opening (hernia defect).

Diagnosis of Hernia

The diagnosis of hernia is usually a clinical one, which means that your doctor will go through a history of your symptoms followed by a brief physical examination. During this check up she/he may feel the area of bulge by raising your abdominal pressure ( this is done by making you stand/cough ), as this manoeuvre makes the hernia more obvious. In case you have an inguinal hernia, the doctor will feel for the potential pathway by examining along your scrotum. To summarise, in vast majority of cases where there is an obvious swelling in the groin/abdominal area, which increases in size on standing, straining or coughing, a clinical diagnosis of hernia is made and NO TESTS are needed. More challenging diagnoses are best performed by hernia specialists.

Types of Hernia

INGUINAL HERNIA This is the commonest type of hernia that occurs in the groin area at the top of the inner thigh. Commonly found in men, it is associated with ageing and repeated strain on the abdomen. An inguinal hernia or its repair should not be taken lightly because neglect in either of the situations can impair blood supply to the testicles, since the blood vessels that supply the testicles pass through the areas where this hernia occurs. Impaired blood supply may cause death of the testicular tissue requiring its removal.

FEMORAL HERNIA Found more commonly in women, this also occurs in the groin area, just above the line separating the abdomen and the legs. A femoral hernia should not be neglected as it has high chances of strangulation, which is a medical emergency. In fact almost half of femoral hernias first come to light as emergencies. Thus femoral hernias should be repaired at the earliest, before the complications ensue.

UMBILICAL HERNIA It occurs when fat or a part of the bowel bulges through the abdomen near the belly button. It is found in babies when the opening in the abdomen through which the umbilical cord passes doesn't seal properly after birth. It is also found in adults due to repeated strain on the abdomen.

EPIGASTRIC HERNIA It occurs in the midline of the abdomen, in the area between the naval and the lower part of the breastbone ( sternum ). This hernia always occurs in the midline because it comes out between the two rectus muscles of the abdomen that meet in the midline. Although the lump may sometimes appear off the midline, the defect/opening is always in the midline. It may be found in infants too because of congenital weakness in the midline of the abdominal wall.

INCISIONAL HERNIA It occurs at the site of a previous abdominal surgery for another cause, during which the abdominal muscles were cut open to allow the surgeon to enter the abdominal cavity to operate. Although the muscle is sutured ( stitched ) during closure, it becomes a relative area of weakness, potentially allowing abdominal organs to herniate through the incision line.

Some of the other uncommon hernias include Obturator hernia, Spigelian hernia, Hiatus hernia, Diaphragmatic hernia, Stoma hernia.