Hernias: symptoms, causes, diagnosis and treatment

What is a hernia?

A hernia is the protrusion of internal tissue, such as intestines, through a weakened section of the abdominal wall. If left untreated, the split in the muscle widens and greater amounts of tissue or organs are pushed through the opening, forming a sac. This visible lump or bulge is one of the key characteristics of a hernia.

The weakened abdominal wall can be present at birth or may develop later in life. The most common site is the groin, but hernias can also form in other areas, such as the navel. If the lump can be gently pushed back through the abdominal wall, it is known as a reducible hernia. If the lump resists manual pressure, it is a non-reducible hernia, which can mean serious complications.

Both forms of hernia require surgical repair. Approximately 40,000 Australians have their hernias surgically repaired every year, making this one of the most common operations.

Symptoms of a hernia

The symptoms of a hernia can vary depending on the location and severity, but may include:

• A visible lump or a swollen area
• A heavy or uncomfortable feeling in the gut, particularly when bending over
• Pain or aching, particularly on exertion (such as lifting or carrying heavy objects)
• Digestive upsets, such as constipation
• The lump disappears when the person is lying down
• The lump enlarges upon coughing, straining or standing up.

Different types of hernias

The abdominal wall isn’t a solid sheet of muscle; it is made up of different layers. Certain areas are structurally weaker than others and therefore more likely to develop hernias. The different types of hernia include:

• Inguinal – occurring in the groin. This is the most common form, accounting for more than nine out of 10 hernias. Abdominal tissue, which may contain a section or loop of intestine, pushes against the small ring of muscle in the groin, eventually splitting the muscle fibres apart. Inguinal hernias affect more men than women and are particularly common in middle age.
• Femoral – occurring high on the thigh, where the leg joins the body. Similar to the events that cause an inguinal hernia, internal abdominal tissue, which may contain a section or loop of intestine or more commonly fatty tissue, forces through the weak muscle ring at the femoral canal until it protrudes. If the herniated section contains bowel this is at risk of strangulation, which is a serious complication requiring urgent medical attention. Femoral hernias are more common in women.
• Umbilical – a portion of the gut pushes through a muscular weakness near the navel, or belly button. This type of hernia is more common in newborns. Overweight women, or those who have had several pregnancies, are also at increased risk.
• Incisional – after abdominal surgery, the site of repair will always be structurally weaker. Sometimes, internal abdominal tissue and sometimes he intestines can push through the closed incision, causing a hernia.

Strangulated hernia

If the hernia resists manual pressure and can't be popped back through the abdominal wall, it is known as a non-reducible hernia. This means that the herniated tissue is held tight by the muscular ring, which can lead to swelling and eventual strangulation of the entrapped tissue. If the entrapped tissue contains bowel, the bowel can become obstructed. The femoral hernia is the most susceptible to this complication.

Symptoms of a strangulated hernia include nausea, vomiting and severe pain. Prompt medical attention and surgery is vital. Untreated, a strangulated hernia can lead to gangrene of the trapped bowel.

Surgical procedures for a hernia

Both reducible and non-reducible hernias need to be surgically repaired. The various procedures used depend on the location of the hernia, but may include opening the abdomen and using stitches and nylon meshes to close and reinforce the weakened section of muscle. Inguinal hernias can be repaired using laparoscopic surgery. A slender instrument known as a laparoscope is inserted and the hernia repaired from the inside. This eliminates the need for large abdominal incisions.

Other factors that may have been contributing to the hernia, such as weight gain and increased abdominal pressure (such as from lifting)obesity may need to be addressed. However, the hernia returns in around one out of 10 cases, requiring subsequent surgery.

Hiatus hernia

The diaphragm is a sheet of muscle slung beneath the lungs that is essential to breathing. A central opening in the diaphragm allows the passage of the oesophagus. A hiatus hernia means that a section of stomach protrudes through the hole into the chest cavity. Small hiatus hernias are extremely common.

The muscle forming the join of the oesophagus and stomach is important in swallowing and the prevention of reflux of gastric acid into the oesophagus. Symptoms of hiatus hernia include heartburn and. Inflammation of the oesophagus is a possible complication. Treatment to alleviate the symptoms includes:

• antacid medications
• losing excess body fat; and
• sleeping with the head higher than the feet.

Things to remember

• A hernia is caused by organs, such as intestines, pushing through a weakened section of the abdominal wall.
• The most common site is the groin, accounting for nine out of 10 hernias.
• The only effective treatment is surgical repair.