Types of operation

There are two basic operations; one involves sewing under tension and the other involves the use of a tension-free mesh. In turn there are two ways of performing the operation; direct incisional surgery or laparoscopic surgery.

Bassini method

Sewing under tension is known as the Bassini method (after the surgeon who invented it) and the Shouldice method (after the Toronto clinic that specialises in it). This method involves sewing the sides of the inguinal gap together. The sutures can give way under strain and the damage caused by their insertion can weaken the flesh. The failure rate can be quite high, depending on who does the operation.The Shouldice technique is performed with stainless steel wire, which produces a more secure closure and the Shouldice Clinic pride themselves on not performing any other operation except hernia operations, so they have a high level of specialised expertise. They also minimise the amount of tension, reducing the risk of tearing.

Mesh repair method

The mesh repair method involves folding a patch of plastic mesh over and under the inguinal gap and then stapling it down. Success depends upon the body tissue growing around and through the mesh, forming scar tissue and creating a firm but tension-free barrier against the hernia re-emerging. This can in turn be a problem if the mesh has to be removed, since removal involves taking out a lot of body tissue. And many patients can feel the lump of plastic when walking, climbing stairs or in other activities.

Both methods can be performed by direct incision, i.e. cutting open the abdomen directly above the area of the hernia, or by laparascopy, where a tube is inserted through a small hole and the operation is performed by remote control via a televised view of the area. The scar is smaller with laparascopy, but the risk of error can be higher.

Laparascopic surgery

Laparascopic surgery involves making a much smaller incision and then using tiny cameras to guide the surgeon to the correct location. If mesh is inserted then metal staples are used to conjoin mesh and flesh, and scar tissue also forms over these staples. Follow-up studies indicate that the use of staples simply increases the bulk of the inserted repair and does not reduce the risk of recurrence.

Comparison of methods

Tension repairs are more likely to fail because they depend on the 4 layers of flesh that hold the stitches not tearing under pressure. As a person ages or gains weight, the risk of the stitches tearing increases. Mesh repairs are more of a problem when they fail as it's a difficult business removing mesh into which nerves and flesh have become intertwined.

With all hernia repair surgery there is the risk of failure, pain, numbness and sexual dysfunction. Hernia operations are often considered as an opportunity for junior doctors to get practice before moving on to more complicated operations such as heart surgery, brain surgery or kidney transplants. As a result the surgeon’s inexperience can lead to less than satisfactory results.

Failure

Independent research indicates that sewing under tension can have a failure rate approaching 47% over 5 years and that mesh repairs can have a failure rate approaching 25%. However, institutions such as the British Hernia Centre and the Shouldice Clinic claim much lower rates of failure, as little as 1%. The Shouldice repair, with 4 layers of stitching, is more complicated and surgeons must assist on at least 100 such operations before they are able to do it themselves. It is no surprise then that less experienced surgeons have a much higher failure rate, with poorly trained junior surgeons reaching unacceptable levels of up to 50%.

A hernia operation is deemed successful if there is no bulge in the lower abdomen afterwards. This is regardless of whether you continue to suffer hernia surgery complications such as chronic pain. They call the pain 'inguinodynia' but it hurts like toothache in your groin. Other complications of hernia surgery include impotence, numbness, reduced sexual sensitivity and incontinence. Many men have reported:

• Having to take strong painkillers for life
• Experiencing sharp pain in the groin when they cross their legs or sit down unevenly
• Being able to get an erection but finding it difficult to have an orgasm
• Being unable even to get an erection
• Becoming incontinent
• Having odd tingling sensations in their legs, thighs and groin.

Some people have a good recovery after the operation and never think about the hernia again. They are the lucky ones and, depending on whose statistics you believe, they are in the vast majority. However, a Dutch report which was peer-reviewed and published in August 2000 in the prestigious New England Journal of Medicine tells a less encouraging story. This study compared hernia repair surgery using the mesh vs. stitch methods. It concluded that using mesh to repair hernias that result from surgery is more effective than stitches, but that the likelihood of hernia recurrence after both methods is fairly high, respectively 24% and 48%.

Pain

Chronic post-operative pain is a complication of both types of hernia repair surgery. In one Italian study 25% of patients suffered chronic pain a year after the operation, requiring pain killers on a regular basis. Other studies show figures as low as 10%. One solution to this is to prevent pain by cutting the nerve in the inguinal region (the ilioinguinal nerve), however, this causes numbness. Pain can also occur when scar tissue forms around the mesh and then impinges on the nerves. This is treated by further surgery or with painkillers. The risk of chronic pain as a complication of hernia surgery increases 4-fold in operations for recurrent hernia, reflecting the technical difficulty and increased risk of nerve damage. A Danish study indicated that 12% of patients suffer post-operative pain that interferes with their ability to go for walks, stand for more than 30 minutes, or climb stairs. For some this caused a significant reduction in work and leisure activities and pain also affected their sleep, relationships with other people, mood and enjoyment of life. A small percentage (2.2%) were unable to return to work.

Causes of post-operative pain:

• Nerve damage during surgery or later entrapment in scar tissue
• Post-operative benign nerve tumors (Neuromas)
• Scar tissue or tissue damage
• Misplaced mesh (if used)
• Contracted, scarified and hardened mesh plugs ("Meshomas")
• Infection (usually noted early post-op but sometimes delayed for months or years.)
• Recurrent (or persistent) hernia
• Constriction or narrowing of the internal inguinal ring around the spermatic cord
• Periostitis-inflammation of the outer membrane of the pubic bone due to the presence of permanent suture material inadvertently placed into this layer resulting in chronic inflammation and pain
• Pain from unrelated causes, associated with neither the prior inguinal hernia nor its operative repair (i.e., Non-hernia musculoskeletal, Intra-abdominal, Intra-pelvic, Neurologic, Genito-urinary, Infectious or Vascular origin etc.)

Numbness

Rather than pain, numbness may be one of the long-term complications of hernia surgery. This arises when the nerves that would have caused pain have been inadvertently or deliberately cut. The numbness is experienced across the lower abdomen, in different places depending on which nerves are involved. Everybody's nerves and other internal parts are laid out differently and the surgeon cannot always precisely anticipate where everything is. If nerves are cut then numbness in some part of the lower abdomen is an outcome. Research indicates that deliberate cutting of the nerve doesn't really help reduce the incidence of pain, so it is not recommended. (JAMA Archives of Surgery Vol 139. No 7, July 2004.)

Sexual dysfunction

Inevitably, if you suffer pain in the testicles or groin this will affect sexual function. One study indicated loss of erection in just over 1%, pain related erections in 2% and shooting pains during ejaculation in 1.5%. Overall sexual activity suffered in 4% of patients. As many hernia patients are younger men this is a particularly problematic complication of hernia surgery.

What is the best solution?

It is the awareness that surgery is not a success if it results in complications which ruin the patient's work, social and sexual life, that has prompted researchers writing in the Journal of the American Medical Association to advise 'Watchful waiting' as the preferred response to the discovery of a hernia, rather than immediate recourse to surgery.