Unfortunately, the "darn" is entrenched in surgical practice because it is simple. Junior surgeons, who currently tend to do the bulk of hernia surgery, can pick it up very quickly.

In the 1950s and 1960s, the Bassini technique was resurrected by the Shouldice Clinic in Toronto, which began to produce excellent results.

The Canadian Shouldice technique reinforces the ruptured abdominal wall by stitching through three layers, compared with the one layer of the older method. The tissue overlaps, like a pleat, to create a stronger bond. The Shouldice operation is more difficult. It also takes longer because it incorporates four layers of sutures. "It has to be done meticulously, and if you get one or two of the stitches wrong it falls apart," says Andrew Kingsnorth.

Patients given Shouldice hernia surgery spend less time in hospital, experience less pain after the operation, and fewer than 1 per cent have to return for another operation.

Or so the story goes. But, there's a snag. "You can't just read it in a

book and pick it up," says Andrew Kingsnorth."You have to be taught it, and only 20 per cent of surgeons in the UK currently practise this technique."

Junior surgeons at the Shouldice Clinic in Toronto are closely supervised for the first 50 hernia operations and don't operate on their own until they've notched up 50 more. They're then assessed for a second time after the thousandth hernia repair.

"Only after this assessment is the surgeon considered a fully-fledged, independent operator," says Andrew Kingsnorth. "Our present supervision in Britain of only six herniorrhaphies is therefore clearly inadequate" (see also Br J Surg, October 1992).

Concerned by the figures and quality of hernia repair surgery revealed by charting the trend through its Hospital Activity Analysis Statistics, the UK Department of Health recently invited the Royal College of Surgeons (RCS) to find out whether surgical techniques could be improved.

Their conclusion: there was no clear cut, best practice hernia surgery being taught or available within the standard textbooks for surgery.

One fundamental issue on which there is general agreement is the importance of constructing a solid repair without tension. This can be done by using either the patient's own tissue or a piece of prosthetic material, such as the mesh. The Lichenstein mesh (named after a shrewd businessman who made a small fortune commercializing a technique which surgeons had quietly been using for 20 years), uses a polypropylene patch, or mesh, which is stitched over the rupture, making the repair much stronger and less likely to break down. Andrew Kingsnorth has pioneered this method on the NHS after visiting the Lichenstein Hernia Institute in Los Angeles, California, whose head, Alexander Shulman, claims the failure rate is substantially lower than 1 per cent.

Private clinics, such as the British Hernia Centre and the London Hernia Centre, perform mesh surgery under a local anesthetic. The operation is usually completed in a day, and they recommend that deskbound patients return to work after a few days.

Proponents of its liberal use (ie, those with a commercial interest) claim that reinforcing mesh offers significant advantages over traditional methods of repair (Am J Surg, 157;188: 1989).

However, at some institutions, mesh is recommended in less than 1 per cent of patients with groin hernia (Surg Cl of N Amer, 1993; 73(3): 513).