A hernia occurs when contents of the abdomen (such as part of the intestines) push through a weakened area of the muscle and connective tissue. Common types include umbilical and inguinal hernias. Less common are epigastric and femoral hernias.
Symptoms may range from a painless bulge to considerable pain, swelling, and discolouration. Treatment will normally involve surgery to push the herniated tissue back into the abdominal space, and repair the weakened abdominal wall.
Serious complications can occur when hernias become incarcerated or irreducible (ie: can’t be pushed back through the abdominal wall) which can lead to a strangulated hernia, where the blood supply to the hernia is cut off. A strangulated hernia is a surgical emergency requiring an urgent operation.
Approximately 75-80% of all hernias are inguinal hernias, which can occur in people of any age. Approximately 90% of all inguinal hernia repairs are performed on men.
Inguinal hernias occur as a result of a defect in the inguinal canal - a tubular passage that runs through the lower abdominal muscles in the groin, close to where the abdomen and the thigh join. The defect allows abdominal tissue (usually a short length of intestine) to push out.
Symptoms of an inguinal hernia can vary from person to person. The most common sign of an inguinal hernia is a bulge or lump in the groin. Men may also have a lump, and sometimes swelling, in the scrotum.
The bulge or lump may be painful and the pain may worsen when coughing, sneezing, lifting, or standing for a long time. The lump may become bigger when coughing, bending, or straining. The lump may become smaller with less pain when lying down.
The skin over the hernia may become swollen and red. When the hernia restricts blood flow to the area the skin may look grey or blue.
An inguinal hernia can occur because of an inguinal canal defect that is present at birth (congenital) and/or because of increased pressure within the abdomen. Factors that increase pressure within the abdomen include:
- Excessive, long-term coughing
- Excessive, long-term sneezing
- Strenuous activity
- Straining due to constipation
- Trauma or lifting heavy objects (this causes less than 5% of hernias).
Factors that increase the chances of developing an inguinal hernia include getting older (because muscles weaken with age), having family members with hernias, or previously having an inguinal hernia yourself.
Umbilical hernias most commonly occur in infants but may also develop in adults. They are characterised by bulging around the belly button and may be more pronounced when the infant cries or coughs.
In infants, umbilical hernias are normally painless but they may cause discomfort for adults. Most infants’ umbilical hernias will close of their own accord by age 1 or 2 years. However, surgical repair may be required if they haven’t disappeared by age 4 years, or if they develop in adults.
A femoral hernia occurs when abdominal tissue is forced out of the abdomen through the femoral canal – a tube-shaped channel in the groin near the top of the thigh – forming a bulge that’s usually the size of a grape.
Femoral hernias tend to occur in older people. They are also more common in women, thought to be related to the weakening of the abdominal tissues during pregnancies. The triggers of femoral hernias are similar to those of inguinal hernias – heavy lifting, straining and coughing. All femoral hernias require surgical treatment because they have a high risk of becoming strangulated.
Epigastric hernias appear in a line between the base of the breastbone and the belly button where fatty tissue is pushed through the hernia. Epigastric hernias are often small with few if any symptoms, but may gradually grow larger and become painful. This type of hernia will not go away by itself so worsening symptoms are likely to lead to surgery.
When abdominal tissue protruding through the hernia cannot be gently pushed back in, the hernia is said to be incarcerated or irreducible. This can lead to the blood supply to the intestinal tissue being cut off. When this occurs, the hernia is said to be strangulated.
Strangulation can cause the tissue to die and cause severe pain at the site of the hernia. This may be accompanied by nausea and vomiting due to obstruction of the intestines. This situation is a surgical emergency requiring an urgent operation because of the risk of gangrene.
Hernia repair surgery is one of the most commonly performed types of general surgery and often will not involve an overnight stay in hospital. The purpose of the surgery is to return bulging tissue to its proper place, and then repair the defect in the abdomen with stiches or a mesh patch to prevent the hernia returning.
For umbilical, femoral and epigastric hernias this will likely involve the traditional “open” surgical method where a small incision is made over, or next to, the hernia so the surgeon can see and repair the problem through that incision.
In the case of inguinal hernias, it is now common to have laparoscopic (minimally invasive) surgery.
This "closed" surgical technique involves three small incisions being made in the groin and lower abdomen. A small and narrow telescope (laparoscope) is inserted through one incision and surgical instruments through the other incisions. The surgeon is able to see the hernia on a television screen and uses the surgical instruments to repair the inguinal hernia with a synthetic mesh patch.
Postoperative care, and guidelines for returning to normal activity, should be discussed with your surgeon prior to surgery and before discharge from hospital.
Mayo Clinic (2019). Inguinal hernia (Web Page). Rochester, MN: Mayo Foundation for Medical Education and Research. https://www.mayoclinic.org/diseases-conditions/inguinal-hernia/symptoms-causes/syc-20351547 [Accessed: 31/03/20]
NHS(2016). Hernia (Web Page). Redditch: National Health Service (NHS) England. https://www.nhs.uk/conditions/Hernia/ [Accessed: 31/03/20]
O’Toole, M.T. (Ed.) (2017). Inguinal hernia. Mosby’s Dictionary of Medicine, Nursing & Health Professionals. (10th ed.) St. Louis, MI: Elsevier.
O’Toole, M.T. (Ed.) (2017). Umbilical hernia. Mosby’s Dictionary of Medicine, Nursing & Health Professionals. (10th ed.) St. Louis, MI: Elsevier.
Rather, A.A. (2019). Abdominal hernias (Web page). Medscape Drugs and Diseases. New York, NY: WebMD LLC. http://emedicine.medscape.com/article/189563-overview [Accessed: 31/03/20]
Last Reviewed – March 2020
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