The statistics are worrying. It's four times more dangerous to have a hernia operation than to go without one if you're over 65, according to the Harvard School of Public Health (New Eng J of Med, 6 December 1973). Death rates vary 14 fold between health districts, and up to 20 per cent of operations have to be repeated within five years. To make matters worse, this recurrence rate rises to 30 per cent following a second operation and by as much as 50 per cent after the third.

In the UK, many patients are stuck on long NHS waiting lists. When it's their turn for the knife, the quality of surgical skill required is described as, as best, "variable", partly because the techniques used to perform the hernia repair vary.

"In the past there have been many types of hernia repair hundreds of different sorts," says John Alexander Williams, a surgeon who has carried out a number himself. "The fact that there are so many is a clear indication that most of them aren't good because a lot have been tried and superceded."

Perhaps surprisingly for such a common operation, a good hernia repair is as difficult to perform as complex cancer surgery, so you might think it demands and receives the skills of an experienced surgeon. Not so.

Consultant surgeons are reluctant to specialize in such operations which they regard as mundane and routine. Often, trainee surgeons are left to cut their teeth on hernia repairs and a lack of general interest is partly to blame for their use of surgical techniques which are considered out of date.

"Surgeons are a very conservative bunch and they tend to continue doing the same things if, as the old phrase goes, it works in their hands," says Andrew Kingsnorth, a consultant surgeon at the Royal Liverpool University Hospital and hernia expert. "But we know that experience can consist of doing the wrong things over and over again. This is what's happened in hernia surgery."

A hernia is a bulge, usually in the groin, caused by a weakness in the muscles which form the front wall, or lining, of the abdomen. Surgery pushes back the contents of this bulge and supposedly strengthens the ruptured muscles and ligaments.

Around 80,000 of the estimated 150,000 or so patients who develop hernias each year are admitted for surgery. The abdominal wall may weaken with the passing of time. Sometimes the muscles may be put under a sudden increase in pressure through heavy lifting, sport or coughing. Hernias may occur if you're overweight, or due to the stretching of scars from previous surgery.

There are many different types of hernia, such as the umbilical (near the belly button), inguinal ( the groin), scrotal and femoral (thigh). If left untreated, hernias can get bigger and may cause pain. Sometimes a part of the intestines can slip in and out of the hernia, an entrapment which can lead to permanent strangulation, producing severe pain and sometimes vomiting.

Unfortunately, three out of four surgeons repair the rupture by "darning" it with a criss-cross of stitches that can give way under too much tension. The modern era of hernia surgery began in 1887 with the so-called Bassini operation, named after an Italian who published his techniques in the German medical literature of the day. Although he devised a very effective operation, it was corrupted over the years in the hands of very average surgeons and was successful in only 10 per cent of cases.