MOST PEOPLE would be aware of the general facts surrounding hernias. Hernias occur when increased pressure within the abdomen causes part of the intestines to protrude through a weakness in the abdominal wall, resulting in a soft bulge underneath the skin.
Typically, this bulge is uncomfortable or painful, and accompanied by a heavy or "dragging" sensation in the groin area. It often becomes more prominent as the day progresses or when the patient stands up, strains or coughs, and it will usually reduce or disappear entirely when the patient lies down.
People would also be generally aware that hernias tend to affect men more than women - in fact, men are almost 10 times more likely to experience a hernia than women, and approximately 80 per cent of the most common form of hernia (inguinal) appear in males.
It is perhaps a little puzzling why this should be the case, since most of the risk factors which we associate with hernias,for example, lifting heavy objects and excessive coughing etc are present in both men and women.
To find the answer to this question, we must go right back to our development in the womb, according to director of surgical affairs at the Royal College of Surgeons, Prof Arthur Tanner.
"The reason inguinal hernias are more common in men is that during foetal development, when a testicle descends from the abdomen to the scrotum it creates a tunnel which is called the inguinal canal. It is this area that becomes a particular weakness for hernias."
In theory, the inguinal canal closes almost completely just after birth, leaving just enough room for the spermatic cord to pass through. In practice, however, the canal sometimes doesn't close up properly which leaves a weakened area.
Abdominal weaknesses are not always congenital - they can also be caused by an injury or certain operations (such as appendectomies) in the abdominal area. Regardless of whether there is a pre-existing weakness, extra pressure in the abdomen - caused by exercise, prolonged coughing or sneezing, constipation, even obesity - can cause the abdominal wall to tear.
In extreme cases, a hernia can become very painful and complications (including bowel obstruction or strangulation), though rare, can be life-threatening.
The body cannot repair hernias itself, and so a medical intervention is required.
The commonest treatment is a surgical repair or buttressing of the abdominal wall using a synthetic mesh. This procedure is considered "run of the mill", as surgeries go and is often completed as a day case, but according to Tanner it is not without its risks, particularly for men.
"It is a common operation, but it is not an easy one for surgeons. When you operate on an inguinal hernia, you are working right beside the blood supply to the testicle. If this is damaged, the testicle will perform poorly or not at all.
"While permanent damage to the testicle is uncommon, partial damage or an impact on sperm count is very hard to pick up and there is very little research in this area. So we don't know whether it impacts or not."
The big breakthrough has been the development of laparoscopic surgical techniques.
"Traditionally, we would have approached the procedure from the front, through an incision. With laparoscopic surgery, we are working from behind the weakness to repair it, so the blood supply to the testicle is not put at risk and there is only a tiny, 5mm scar."
Surprisingly, given the improved outcomes and reduced risk of laparoscopic techniques, most patients in Ireland are still offered the traditional form of surgery. The reason for this, according to Tanner, is that the necessary technical expertise is not always available - a product of decentralised surgical delivery.
"Surgical outcomes depend very much on volume of surgery carried out. The more a surgeon does a particular surgery, the better they become at it.
"The laparoscopic surgery requires a steep learning curve and we are inhibiting the spread of that knowledge at the moment. It will change but it is difficult to do so until the delivery of surgery services are rationalised."
Preventing hernia from recurring
Most hernias are successfully treated with surgical intervention but in about one in 10 cases, the hernia can recur as a result of poor tissue healing at the site of repair. "You cannot guarantee 100 per cent that a hernia will not recur after repair surgery," says Dr Bernadette Carr, medical director at the VHI, "because with hernias, it is quite literally cause and effect. If the same conditions continue, then it is quite possible that it will recur and you shouldn't be surprised if it does."
There are, she says, certain risk factors that should be avoided to help make the occurrence (or recurrence) of hernias less likely. "If you are obese or overweight you should try and get your weight back to normal limits, because carrying excessive weight increases pressure on the abdomen.
"There are many reasons for quitting smoking, but in terms of hernias, a long-term chronic smoker's cough puts extraordinary pressure on the abdominal musculature."
Hernias can often occur in very fit men because of a particular exercise they are doing. "In this case they should consult with their doctor or an exercise professional before resuming their exercise regime after surgery," says Carr.
Post-surgery activities recommended are walking, cycling and swimming, while exercises or activities which increase abdominal pressure such as heavy lifting, weight training and sit-ups should be avoided.