What is a hernia?

A hernia is a condition that occurs when an internal organ or fatty tissue pushes through a natural opening or a weakness, usually in the abdominal wall. This may create a bulge that can be felt from the outside. 

Causes

The abdominal wall is made up of layers of muscles and tissues that covers and protect internal organs. Hernias can occur if there is a natural opening or weakness in the abdominal wall. When there is an increase in pressure within the abdomen, from straining, lifting heavy items or coughing, it may cause internal organs or fatty tissues to bulge out through the opening or weak spot in the abdominal wall.

There can be many reasons for the weakness in abdominal wall muscles. It may be caused by repetitive strain on the muscles, which could be caused by continual coughing or sneezing, or by lifting heavy items. Being overweight or pregnant can also create a lot of pressure in the abdomen and may lead to the development of a hernia. With increasing age, the muscles naturally weaken and increase the risk of developing hernias. There are also natural openings or weaknesses in the abdominal wall that form from birth as part of normal development and/or as a congenital abnormality. Internal organs, such as loops of intestine and bladder, and/or fatty tissue may migrate through these openings and lead to hernias.

Depending on the cause of a hernia, they can develop quickly, or over a long period of time.

Hernia anatomy, formation of a hernia, process of hernia formation.A hernia occurs when an organ or fatty tissue pushes through a weakness in the abdomen. 

Abdomen

The part of the body that lies between the chest and the pelvis.

Congenital

Present from birth.

Risk factors

While anyone can get a hernia, your chance of getting the condition increases with age. You are also more likely to get a hernia if you:

  • Have a family history of hernias;
  • Are overweight or obese;
  • Had a previous hernia;
  • Have weak or injured abdominal wall muscles;
  • Have previously had surgery;
  • Are pregnant;
  • Lift heavy items, or;
  • Smoke.

Types

Hernias can be classified into different types based on what part of the abdominal wall they affect.

Inguinal hernias

Inguinal hernias are the most common type of hernia and occur in the groin area. They occur due to several reasons: 

  • There is a natural passage between the abdomen and the genitals, which allow certain structures to pass between them. Fatty tissue, a loop of intestine and/or other internal organs can inadvertently enter this natural opening to create a hernia, and;
  • The abdominal muscles, especially around the groin, are prone to becoming weak with age, daily wear and tear, and weight gain. A hernia can form when internal organs or fatty tissue force their way through these weak muscles.

The symptoms of an inguinal hernia are typical of any hernia, as previously discussed. However, the bulge of an inguinal hernia may be seen in the groin, in the scrotum of men, or only noticeable with straining or coughing. Inguinal hernias affect men more than women and are common in middle-aged people.

Femoral hernias

Femoral hernias occur high on the thigh, where the leg joins the body. They can be confused with inguinal hernias, due to their close position. Femoral hernias are more common in women than men. These hernias tend to be more painful and prone to complications, if not treated.

Umbilical hernia

Umbilical hernias are relatively common and typically cause a bulge around or within the belly button. They can be present from birth and may not cause any symptoms. Risk factors for developing an umbilical hernia include being overweight or obese, and pregnancy. 

Epigastric hernia

Epigastric hernias are found in the middle of the upper part of the abdomen. They tend to be more common in obese people or pregnant women. They tend to be more noticeable with straining or coughing.  

Incisional hernias

Incisional hernias refer to hernias that occur at the site of previous abdominal surgery. They occur when internal organs or fatty tissue force their way through the scar left from previous surgery, which is inherently weaker than normal tissues. Most abdominal surgery has a risk of causing incisional hernias, however this is generally low with modern surgical techniques. Your surgeon can discuss your particular risk based upon your health and the procedure being performed.  

Common locations where hernias can develop. 

Abdomen

The part of the body that lies between the chest and the pelvis.

Groin

The area where the abdomen joins the thighs.

Signs and symptoms

The symptoms of a hernia may include discomfort or pain usually with straining or physical activity, a bulge that may be felt and/or seen, and heaviness or tugging sensation in the groin. Occasionally, there may be no symptoms and your doctor may diagnose a hernia on a routine physical exam or following a scan for another reason. 

Man with abdominal pain.A hernia can cause abdominal pain usually with straining or physical activity. 
 

Groin

The area where the abdomen joins the thighs.

Methods for diagnosis

In most cases, hernias can be diagnosed with a physical exam. Your doctor may check for a bulge in your abdomen or groin that gets bigger when you cough, strain or stand.

In some cases, hernias may need to be diagnosed using imaging techniques such as an ultrasound or computerised tomography (CT) scan. These tests allow the doctor to assess the location, size and number of hernias present, as well as ascertain the internal organs or tissues that are present within the hernia. This greatly assists in planning the treatment of the hernia. 

Abdomen

The part of the body that lies between the chest and the pelvis.

Computerised tomography

A scan that uses X-rays to create a 3D image of the body. This can detect abnormalities more effectively than a simple X-ray can.

Ultrasound

A scan that uses high-frequency soundwaves to produce images of the body’s internal structures.

Groin

The area where the abdomen joins the thighs.

Types of treatment

It is generally encouraged that hernias, even if there are no symptoms, are treated before they get bigger over time or cause complications. Some hernias, may be temporarily treated by your doctor gently pushing them back into the body cavity, especially if they are acutely painful or confined. However, even these are recommended to be permanently treated to prevent it recurring. 

Most hernias are treated using surgery. However, where an individual may not be suitable for surgery, or to allow time to plan for surgery, a hernia truss may be used. This is a supportive undergarment that can be used for inguinal hernias to reduce discomfort. 

What happens during the procedure?

Hernia operations are variable depending on the type and number of hernias, patient factors and surgeon preferences. However, all are done under anaesthesia in a hospital, usually under a general anaesthetic, but occasionally local anaesthesia may be used. There are two main types of hernia operations, which are:

Open hernia repair

In this procedure, a surgeon will make a generous incision over or near the bulge, to push the structures within the hernia back into the body cavity. The opening or weakness in the abdominal wall that led to the hernia is then strengthened by sewing layers of the abdominal wall together and/or using a prosthetic mesh to reinforce the abdominal wall.   

Laparoscopic hernia repair

During a laparoscopic hernia repair, a surgeon will make several small cuts in the abdominal wall to insert surgical instruments and a laparoscope, which is a camera attached to a telescope to give a view of the procedure. Guided by the camera, the surgeon will use the surgical instruments to repair the hernia with stitches and/or using a prosthetic mesh. This procedure is less invasive than an open hernia repair, and often results in quicker recovery.

What happens after the procedure?

Following a hernia operation, you may be required to stay in hospital depending on the type of procedure, its complexity, and any health concerns. You will generally require pain-relief medications for a short period and be advised to avoid strenuous physical activity and heavy lifting for several weeks following the procedure. The first few months after a hernia operation is when there is the greatest risk that the surgery fails and the hernia recurs. Strictly following any advice from your surgeon can reduce this risk greatly. Gradual return to physical activity is always recommended, once your surgeon is comfortable with your recovery.

Some immediate complications of the procedure include wound infection and urinary retention. Signs of wound infection include increase in pain at the wound site, redness, and discharge. If these are present, it is important to promptly seek medical attention. Urinary retention is the inability to pass urine and it can develop immediately after surgery or in the following first few days. It is a temporary condition that is more common following inguinal hernia repair and in men with prostate gland problems. Generally, you will be kept in hospital until you adequately pass urine before being allowed to go home. However, if you notice difficulty with urination once at home, it is advisable to seek medical attention. 

Anaesthesia

An insensitivity to pain and other sensations, induced by an anaesthetic.

Prostate gland

A male reproductive organ that surrounds parts of the bladder and urethra. It secretes a sperm-nourishing component of semen.

Prosthetic mesh

A small net with different pore sizes, made from materials such as polyester, that is used as an implant to repair hernias.

Potential complications

If a hernia is not treated, it can grow larger and become very uncomfortable. Surgery to then repair the hernia becomes more complex. 

Hernias can also develop other certain complications. Internal organs and/or fatty tissues within the hernia are at risk of becoming stuck inside the hernia. This is referred to as an incarcerated hernia. An incarcerate hernia runs the risk that the blood supply to the internal organs or fatty tissue inside the hernia becoming compressed. If this occurs, these organs or fatty tissue can begin to die, releasing toxins that can make the individual extremely unwell and potentially lead to death (if not immediately treated). This is known as a strangulated hernia. Symptoms that a hernia has strangulated often include sudden-onset extreme pain, unwellness, and vomiting. It is important to seek prompt medical attention if these symptoms are present. 

If the strangulated tissue is bowel, it can result in a mechanical obstruction of your bowel (see bowel obstruction). This typically causes severe abdominal pain, nausea and vomiting, constipation and abdominal distension. Again, this is a serious condition which needs prompt medical attention. 

Complications with a hernia, hernia strangulation, untreated hernia complications.Anatomy of a strangulated hernia. 

Abdominal distension

A swelling or enlargement of your digestive tract, due to several causes. Also known as bloating.

Prognosis

The outlook for a hernia depends on the type and size of the hernia. If treated early, the outlook for hernia repairs is generally good. However, it is important to try to reduce the risk factors associated with the development of the hernia. After hernia surgery, anything that places lots of strain on the affected area should be avoided for six to eight weeks to reduce the chance of the hernia coming back. A hernia can return even after it has been repaired. Following general prevention advice can reduce the chance of it recurring. 

Prevention

There are some things that may reduce your risk of developing a hernia, which include:

  • Avoiding heavy lifting;
  • Quitting smoking - smoking causes coughing fits that can strain the hernia;
  • Eating a healthy diet high in fibre, to avoid strain due to constipation, and;
  • Maintaining a healthy weight.