►  What is a hernia?

A hernia occurs when there is a hole in the muscles of the abdominal wall. This hole allows the contents of the abdomen to poke through the hole. Usually those contents can be temporarily pushed back inside again but sometimes they cannot. This is called an irreducible hernia and is potentially dangerous because then the contents of the hernia can lose their circulation. The hernia is then strangulated and needs emergency surgery. If the contents of the hernia are intestines, the situation can be life-threatening. Luckily, the vast majority of hernias are reducible and the risk of strangulation is low.


►  How do you know if you have a hernia?

A hernia is a swelling or bulge that usually varies according to position. It usually disappears on lying down because of gravity and protrudes on standing up, especially after exercise. Often, but not always, the hernia is painful, usually a dragging sensation which is worse with increasing activity. The pain is in the vicinity of the hernia but sometimes spreads, for example, down to the testicle

►  How do you get a hernia?

Sometimes there is a weakness in the abdominal muscle from birth and indeed babies’ hernias are quite common. The most common hernias are in the groin, just above the groin crease (called inguinal hernias) and these are far and away more common in men as the area has a natural hole to allow the blood vessels and vas to come out of the abdomen to go down to the testicle. Sometimes with age, the hole enlarges and the hernia becomes apparent - the hernia is noticed, say, in the shower. Sometimes the hernia is made more obvious by heavy lifting or straining and sometimes the hole itself is produced by heavy lifting and the person experiences sudden pain.

►  What next – is it dangerous?

The presence of a hernia is almost never a sign of anything more serious. However, the hernia hole never repairs itself. It needs surgery to fix it. Some hernias are painful and prevent normal physical activity. Other hernias keep enlarging and these both ought to be repaired. Hernias that are difficult to reduce (get the hernia contents back into the abdomen) need more urgent surgical repair. If the hernia is tense, painful and irreducible, emergency repair is required. However, some non-painful small inguinal (see below) hernias can simply be repaired when and if the patient so wishes, but it should be remembered that the hernia never gets any smaller and never goes away. Another consideration is the convenience of repair – if the person is going to a place where it may be difficult to get emergency surgery should it be required, then it might be prudent to have the hernia repaired beforehand.  Some people will not pass their medicals or fitness to work, unless the hernia is repaired (eg pilots in some jurisdictions). In fact, there is a risk of the hernia enlarging suddenly with change in air pressure in planes and when considering flying, patients should consult their doctor first.

Some types of hernia should be repaired regardless (see below).

Types of hernia

Inguinal: These are the most common. They are in the groin, above the groin crease, but as they enlarge, they extend to into the scrotum. The hernia contents are usually either fatty tissue or intestine. Quite often these hernias occur on both sides and when one side is repaired, it is not long before the other side declares itself (but refer to “treatment” below).

Femoral: These are smaller, occur more often in women and are little lumps below the groin crease. They can be difficult to distinguish from inguinal hernias. They are more likely than inguinal hernias to strangulate and they therefore should be repaired in all cases.

Umbilical: These hernias are in the navel or belly button. They occur commonly in babies and disappear with time but this does not happen in adults. In adults, the hernias tend to get bigger with time. When small and painless, they need not be repaired but they are more difficult to repair as they get larger, so I advise repair of most umbilical hernias, especially if they are indeed getting bigger. As with inguinal hernias, if there are periods of irreducibility, the hernias definitely need repair. Note, for this discussion, “paraumbilical” is equivalent to “umbilical”.

Spigelian:  This is a rare hernia in the lower part of the abdomen. It is often painful and nearly always needs repair.

Incisional: These hernias occur through a previous incision. There is a hole in the scar where the wound has not healed properly for various reasons and intestine protrudes through the hole. Sometimes there are multiple holes, especially if the previous repair or closure was performed with Nylon. These hernias tend to enlarge with time, are often painful and often involve intestine, and are much more difficult to repair if they are allowed to become large. They therefore ought to be repaired early, as long as the circumstances permit.

Epigastric hernias: These are usually very small hernias in the upper part of the abdomen and are usually very painful, so need repair

Other hernias: There are other very rare hernias, such as lumbar, obdurator and Morgagnis hernia. These ought to be repaired too. They often present as emergencies as they were previously not noticed.

Hiatus hernia: This is a hernia of the oesophagus through the diaphragm and is associated with gastro-oesophageal reflux – please refer to separate listing on website.

Sportsman’s hernia: This is a tear of a tendon in the groin as a result of an injury during physical exercise – please refer to separate listing on website.


►  Treatment

Non-surgical options;  A truss is a belt-like device that holds the hernia inside, preventing it protruding. It is quite expensive and not at all reliable. It may be an option if the patient does not want or cannot have an operation and the hernia is painful.

Surgery:  Surgical repair of the hernia defect involves one of three different approaches.  The technique employed will depend on the size of the hernia, the size of the patient, the type of hernia, the number of hernias and whether the hernia has been repaired before.

1.     The simplest repair is to suture the edges of the hole together. The advantages are the low cost, limited scar and limited equipment and material used. The disadvantages are that the repair can be more painful and also weaker than other methods, especially if the hernia is large and the patient heavy. For small hernias such as epigastric and femoral hernias and for some small umbilical hernias, suture repair is usually perfectly adequate. I use absorbable sutures that slowly disappear over six months. Some surgeons use permanent sutures but these ten to cut through the tissues over time like cheese wire and thus weaken the repair. These sutures are also associated with infection of the suture itself, called suture sinus.

2.     Mesh repair of hernias has become the most common method of repair for inguinal hernias and incisional hernias. The mesh is made of either polypropylene or polyester. It acts as scaffolding for the body’s healing scar to fill in the hole, a bit like fibreglassing. The mesh covers the hole but also widely overlaps the hole so it adheres to the healthy tissue around the hole. Then after the operation, over the next few weeks, the body’s healing scar gets incorporated into the mesh, thus sealing over the hole for good. The mesh is permanent. The mesh is secured in place with sutures. Repairing hernias this way is what we call “tension-free repair”; the hernia edges aren’t pulled together under tension so that there is less strain on the repair, especially with physical activity such as coughing and less chance of the sutures tearing out through the tightened tissues. Because there is less tension, there is less pain after the operation too.

 There are two methods for getting the mesh over the hole:

a.     An incision is made over the hernia and dissection proceeds down to the hernia defect, which is carefully defined. The mesh is then placed over the hole and secured in place with sutures. Thi is called open mesh repair

b.     An incision is made a good distance away from the hernia and a telescope (called a laparoscope) inserted. The dissection of the hernia is made on the inside and the healthy muscle tissues around the hernia are exposed on the inside of the hole. The mesh is then inserted to lie over the hole on the inside. This laparoscopic repair has further advantages:

                                          i.    Even less post-operative pain

                                         ii.    Much less chance of wound infection

                                        iii.    Less damage to healthy tissues during dissection (such as damage to testicle blood vessels and nerves)

                                        iv.    Much reduced chance of mesh infection

                                         v.    Probably stronger repair as there is even wider coverage or overlapping of mesh over the healthy surrounding tissues to reduce the chances of repair failure.

                                        vi.    For recurrent hernias, the surgeon operates through healthy virgin tissue.

                                       vii.    For incisional hernias, there is a major advantage in being able to see if there is more than one hernia hole defect. Oftentimes the previous incision had failed in several places and one cannot tell by examining the patient that this is the case. With the laparoscope place inside the abdomen, the surgeon can see the entire abdominal wall from the inside and locate all the defects. The open technique sometimes fails to identify other hernia defects than the obvious one.

The main disadvantage of laparoscopic repair is the cost – the cost of the equipment used during the operation which is technically more difficult than open repair.

3.     Other forms of hernia repair are more complex and used for very large incisional hernias. They involve complex dissection of the area widely around the hernia to bring healthy tissue into the hernia defect. This is called component separation technique.

The following table sets out my preferences for hernia repair for the most common hernias:

Hernia type



Acceptable alternative

Less acceptable


Open suture

Open mesh






Open mesh


Inguinal both sides




Open mesh

Inguinal recurrent






Open mesh





Open suture

Open suture






Open mesh



Open suture


Open mesh



For laparoscopic incisional hernia repair, special mesh is used. It is covered with a film that prevents bowel adhering to it. If this happens, the bowel can become kinked and obstructed, or worse, the bowel is damaged and leaks onto the mesh and out through the abdominal wall (called fistula).

Special notes regarding laparoscopic incisional hernia repair: There is always a temporary bulge that develops post-operatively where the hernia was – it goes away in time. And, unlike other laparoscopic procedures, laparoscopic incisional hernia repair is still quite painful.


►  Laparoscopic inguinal hernia repair

This is the most common hernia operation I do. A 12-15mm incision is made just under the umbilicus (navel) for the laparoscope and two 5mm incisions either side for instruments to do the dissection. The space between the muscles and the lining of the abdominal cavity (called the peritoneum) is developed.  The hernia is dissected out and mesh is passed down the larger incision, carefully positioned over the hole (like repairing a tyre) and secured in place with absorbable staples. I usually then dissect out the other side as there is about a 20% chance there is a hernia there too even though it was not detected pre-operatively. It is a shame to have to come back a few months later to have the other side repaired, just because the surgeon failed to look for the (other) hernia at the first operation.  The mesh is large enough to well and truly cover the hole. I usually use a piece of polyester, 15 x 12cm in size. Because the coverage is so wide, and the mesh is on the inside of the hole there is little chance of the mesh slipping and failing to cover the hole ie little chance of repair failure.

Most of my patients return to normal activities quickly. (for example, playing for the All Blacks two weeks after surgery!). Many require no pain killers at all after the operation. However everyone is built differently and everyone reacts differently to surgery so recovery rates do vary.

Unfortunately, because of cost considerations, laparoscopic inguinal hernia repair is not commonly performed in the public hospital.


Any exceptions?

Almost all inguinal hernias can be repaired using the laparoscopic technique. Redo repairs are more difficult and scars from previous operations in the lower abdomen also make the surgery more difficult. Patients who have had radical prostate surgery or who have had pelvic fractures are especially difficult and I avoid the laparoscopic approach.

For more details, please see elsewhere on website


Ø  Recurrence rate

Unfortunately, any hernia repair can fail over time. The chances of this happening have been reduced with the advent of mesh repairs. One of the most important factors in chances of failure is who it is who performs the operation. This is particularly true for the laparoscopic repair which is technically challenging and requires special skills and a lot of patience. The learning curve is quite long and may be as long as 200 cases because the relevant anatomy has to be relearnt. It is important therefore to choose an experienced surgeon. I have performed thousands of laparoscopic hernia repairs and was the first in Wellington to do so, 20 years ago.  I have taught the technique to many other surgeons .


For inguinal, epigastric, umbilical and femoral hernias hernias, the recurrence rate should be less than 2% even after many years. Incisional hernias are the most prone to recur and even with excellent technique, the recurrence rate is still around 10%, increasing with the size of the hernia


Ø  Recovery

Usually, the patient is admitted to hospital on the day of the surgery. The operation takes about an hour (less for umbilical and epigastric hernias, more for incisional hernias). The operation is usually done under general anaesthetic (the patient is completely asleep and unaware). All laparoscopic repairs require general anaesthetic but open inguinal mesh repairs can often be done under local anaesthetic (injection in the area of operation to numb the skin and underlying tissues).

The length of stay varies. Often it is just a few hours, although many patients prefer to stay overnight. For incisional hernias, the stay is usually two nights, often longer.


The time to return to work depends on whether it is physical work or not. For non-physical work, the time off is just long enough to recover from the effects of anaesthetic and operation – about a week or so. For all suture repairs there should be no lifting or straining, running or jumping for six weeks. Similarly for incisional hernia repairs.  For open mesh inguinal repairs: no lifting for four weeks. For laparoscopic inguinal repairs: no restriction on physical activity.

Usually there are no sutures need to be removed post –operatively.



Sometimes hernias are caused by lifting heavy objects or sudden strains. If there is a history of a specific event that caused immediate pain, associated with the appearance of a lump shortly afterwards, and the patient promptly reports to their General Practitioner, then ACC will often accept this hernia occurrence as an accident. If so, I, as the surgeon, will apply to ACC to cover the costs of repair at Southern Cross Hospital. Southern Cross Hospital has a special contract with ACC to perform these operations so that the patient does not have to pay anything at all. Other hospitals however may still ask the patient to pay something towards the cost of an ACC-funded operation (even 50%). The application process with ACC takes about a month, from the time of initial filing to the time of final approval. It is imperative that both stages of approval are passed before surgery is undertaken (initial liability cover and operation cover). For patients who have private insurance cover, once the ACC process is commenced, it must be completed as insurance companies will not cover cases that ACC would cover.


►  What else?

With modern techniques, chances of failure are low but do occur, especially if the patient and the hernia are large. Wound infection is a complication of any operation but if the repair has been an open mesh repair, then, the worry is that the mesh will also get infected. If it does, the repair will likely fail, the mesh will have to be removed and the repair redone.

Bruising is very common after inguinal hernia repair and sometimes can be dramatic but actually it almost always represents a very small volume of blood and there is nothing to worry about. Sometimes the scrotum swells but this also settles.

For incisional hernias, there is a risk of damage to the bowel if it is firmly attached to the old scar. The risk is low but it is a serious complication.

P: 04 9102 178 E: gary.stone@wgtnspecialist.co.nz F: 04 3895230