Use of Mesh in Hernia Operations

Mesh has routinely been used in hernia repairs in the last 20 years for all groin hernias as well as hernias in the abdominal wall that are more than 2 cm in diameter. Lately, there is lots of controversy with regards to the use of mesh in abdominal surgery.

Recent Controversies With Use of MeshIn the last 2-3 years, there has been increased reporting of complications of mesh use.  Most of these have been in the newspapers.  Most of the problems with the use of mesh has been as part of gynaecological procedures, mostly to treat prolapse or incontinence.

There are 2 problems that I was a general surgeon can see with regards to the use of mesh in these procedures.  The first reason is that this mash is placed under the organ (usually bladder or womb).  When a woman is standing, these organs are by gravity being pulled down and the mesh is holding them in place and tension is placed onto the mesh from the organs above.  This mesh can slowly cheese-wire into these organs and cause problems.

The second reason is that this mesh is placed into the abdominal cavity and will cause scarring inside.  This scarring can cause a twisting of the bowel and bowel obstruction.
The second reason also occurs in general surgical procedures where the mesh is placed within the abdominal cavity.

Why Do We Surgeons Use Mesh in Hernia Operation? Mesh is used to minimising the risk of hernia recurrence.  This risk is different in different hernia operations.  For groin hernias, the risk of recurrence can be up to 30-40% if the mesh is not used.  The only place in the world that has low rates of recurrence for the repair of groin hernias without mesh is Shouldice Hernia Hospital in Canada.  No other hospital has managed to achieve these low levels of risk of recurrence in the world.  The recurrence rates following groin hernia repair with mesh are less than 5%.  The recurrences following abdominal groin hernia repairs are around 10-20% depending on the size of a hernia (those that are more than 10cm have higher recurrence rates) and patients obesity. 

Mesh was developed to strengthen the area and cause ingrowth of the tissue into the mesh.  These meshes do not resorb with time, although some do partially reabsorb. 
The mesh placement is different for different types of surgery and where a hernia is.

Placements of the mesh:
    • Abdominal wall hernia (umbilical and ventral)
       ○ Laparoscopic (keyhole repair) - the mesh is placed inside the abdominal cavity
      ○ Open repair - mesh can be placed outside or inside the abdominal cavity.  This is influenced by the size of a hernia and surgeon preference.
    • An inguinal hernia (groin)
     ○ Laparoscopic repair - the mesh is placed behind the abdominal wall muscles, but in front of the peritoneum (the smooth lining of the abdominal cavity).  Mesh is not within the abdominal cavity and is not exposed to abdominal organs unless the hole in the peritoneum was made during repair of a hernia
        ○ Open repair - the mesh is placed over the abdominal wall muscles, just behind the tough sheath called external oblique fascia.  Mesh is not exposed to the abdominal cavity unless plug mesh used (this technique is not commonly used by surgeons in New Zealand)
    • A femoral hernia (groin) - mesh not used all the time.
     ○ Laparoscopic repair - same as for an inguinal hernia above.
        ○ Open repair - mesh placed next to the femoral vein, outside of the abdominal cavity.

Problems with mesh adhesion or scarring inside the abdominal cavity.  In this situation, abdominal organs close to the repair site get stuck to themselves or to the mesh.  These symptoms can be caused:
    ○ Bowel obstruction - pain, abdominal distention and vomiting
      ○ Bowel twisting - extreme pain, bowel rupture, nausea, vomiting and rarely distention
    • Scarring outside the abdominal cavity
        ○ Being able to feel the scar/mesh - usually only in skinny people
        ○ Pain - due to injury to sensory nerves in the groin - either during the surgery or being pulled into scarring by the mesh.

Why are hernias being repaired? Hernias should only be repaired if they cause you significant problems.  If hernias are not symptomatic, they should not be repaired.  The risks of hernia repair surgery always need to be taken into account. 

The problems that hernias may cause are pain, bowel obstruction (blockage) and a bowel perforation.  On average,  they will slowly increase in size.

You should always discuss both the risks and benefits of any surgical procedure with your surgeon.  At the end of the day, the benefits of surgery need to outweigh the risks.

​Always discuss the risks and benefits of hernia surgery with your surgeon.  Ask any question that you may have, of your surgeon.  In the end, you are the only one who can make the decision whether or not to have surgery and is it worth it or not.