It can often be harmless and pain-free, but at times it can bring discomfort and pain.
In this article, we investigate what a hernia is, the common causes of hernia, and how they are treated.
Here are some key points about hernias. More detail and supporting information is in the main article.
- Hernias often produce no troublesome symptoms, but abdominal complaints may signal a serious problem.
- They are usually straightforward to diagnose, simply by feeling and looking for the bulge.
- Treatment is a choice between watchful waiting and corrective surgery, either via an open or keyhole operation.
- Inguinal hernia surgery is more common in childhood and old age, while the likelihood of femoral hernia surgery increases throughout life.
Overview: What is a hernia?
A hernia occurs when there is a weakness or hole in the peritoneum, the muscular wall that usually keeps abdominal organs in place.
This defect in the peritoneum allows organs and tissues to push through, or herniate, producing a bulge.
The lump may disappear when the person lies down, and sometimes it can be pushed back into. Coughing may make it reappear.
Hernias can commonly be found in the following areas:
Groin: a femoral hernia creates a bulge just below the groin. This is more common in women. An inguinal hernia is more common in men. It is a bulge in the groin that may reach the scrotum.
Upper part of the stomach: a hiatal or hiatus hernia is caused by the upper part of the stomach pushing out of the abdominal cavity and into the chest cavity through an opening in the diaphragm.
Belly button: a bulge in this region is produced by an umbilical or periumbilical hernia.
Surgical scar: past abdominal surgery can lead to an incisional hernia through the scar.
With the exception of an incisional hernia (a complication of abdominal surgery), in most cases, there is no obvious reason for a hernia to occur. The risk of hernia increases with age and occurs more commonly in men than in women.
A hernia can be congenital (present at birth) or develop in children who have a weakness in their abdominal wall.
Activities and medical problems that increase pressure on the abdominal wall can lead to a hernia. These include:
- straining on the toilet (due to long-term constipation, for example)
- persistent cough
- cystic fibrosis
- enlarged prostate
- straining to urinate
- being overweight or obese
- abdominal fluid
- lifting heavy items
- peritoneal dialysis
- poor nutrition
- physical exertion
- undescended testicles
Risk factors for hernia
The risk factors can be broken down by hernia type:
Incisional hernia risk factors
Because an incisional hernia is the result of surgery, the clearest risk factor is a recent surgical procedure on the abdomen.
People are most susceptible 3-6 months after the procedure, especially if:
- they are involved in strenuous activity
- have gained additional weight
- become pregnant
These factors all put extra stress on tissue as it heals.
Inguinal hernia risk factors
Those with a higher risk of inguinal hernia incude:
Smoking tobacco increases the risk of inguinal hernias.
- older adults
- people with close relatives who have had inguinal hernias
- people who have had inguinal hernias previously
- smokers, as chemicals in tobacco weaken tissues, making a hernia more likely
- people with chronic constipation
- premature birth and low birth weight
Umbilical hernia risk factors
Umbilical hernias are most common in babies with a low birth weight and premature babies.
In adults, the risk factors include:
- being overweight
- having multiple pregnancies
- being female
Hiatal hernia risk factors
The risk of hiatal hernia is higher in people who:
- are aged 50 years or over
- have obesity
In many cases, a hernia is no more than a painless swelling that presents no problems and needs no immediate medical attention.
A hernia may, however, be the cause of discomfort and pain, with symptoms often becoming worse when standing, straining, or lifting heavy items. Most people who notice increasing swelling or soreness eventually see a doctor.
In some cases, a hernia needs immediate surgery, for instance, when part of the gut becomes obstructed or strangulated by an inguinal hernia.
Immediate medical attention should be sought if an inguinal hernia produces acute abdominal complaints such as:
- the bulge cannot be pushed back into the abdomen
The swelling, in these cases, is typically firm and tender and cannot be pushed back up into the abdomen.
For a hernia without symptoms, the usual course of action is to watch and wait, but this can be risky for certain types of hernia, such as femoral hernias.
Within 2 years of a femoral hernia being diagnosed, 40 percent result in bowel strangulation.
It remains unclear whether non-emergency surgery is worthwhile for hernia repair in cases of an inguinal hernia without symptoms that can be pushed back into the abdomen.
The American College of Surgeons and some other medical bodies consider elective surgery unnecessary in such cases, recommending instead a course of watchful waiting.
Others recommend surgical repair to remove the risk of later strangulation of the gut, a complication where blood supply is cut off to an area of tissue, which requires an emergency procedure.
These health authorities consider an earlier, routine operation preferable to a more risky emergency procedure.
Types of surgery
Belly button following hernia surgery.
Although surgical options depend on individual circumstances, including the location of the hernia, there are two main types of surgical intervention for hernia:
- open surgery
- laparoscopic operation (keyhole surgery)
Open surgical repair closes the hernia using sutures, mesh, or both, and the surgical wound in the skin is closed with sutures, staples, or surgical glue.
Laparoscopic repair is used for repeat operations to avoid previous scars, and while usually more expensive, is less likely to cause complications such as infection.
Surgical repair of a hernia guided by a laparoscope allows for the use of smaller incisions, enabling a faster recovery from the operation.
The hernia is repaired in the same way as in open surgery, but it is guided by a small camera and a light introduced through a tube. Surgical instruments are inserted through another small incision. The abdomen is inflated with gas to help the surgeon see better and give them space to work; the whole operation is performed under general anesthetic.
Hernia in children
Inguinal hernia is one of the most common surgical conditions in infants and children.
A 2014 systematic review of 20 years of data on conventional open hernia repair (herniorrhaphy) and laparoscopic hernia repair (herniorrhaphy) in infants and children found that laparoscopic surgery is faster than open surgery for bilateral hernias, but that there is no significant difference in operating time for unilateral inguinal hernia repair.
The rate of recurrence is similar for both types of procedure, but complications, such as wound infection, are more likely with open surgery, especially in infants.