- What is a hernia? What causes a hernia?
- How does a hernia present?
- Umbilical hernias
- Epigastric hernias
- Incisional hernias
- Inguinal hernias: treatment
- Laparoscopic hernia repair
- ACC and Hernias: how does it work? (New Zealand only)
- Recovery from laparoscopic hernia repair
- What sort of surgeon performs laparoscopic inguinal hernia repair?
- Andrew Bowker’s experience with laparoscopic inguinal hernia repair
What is a hernia? What causes a hernia?
A hernia occurs when a part of the abdominal contents push through a defect in the muscle wall, much in the way an inner tube pushes through a split in the tyre casing.
A swelling becomes apparent on the abdominal wall, most commonly in the groin region, where it is known as an inguinal hernia. Usually it is more obvious when standing, as the effect of gravity encourages abdominal contents to fall into the hernia sac. Conversely, the swelling usually disappears completely when lying down, and the contents drop back into the abdominal cavity proper. The hernia contents usually consist of either intestine or fatty tissue called the omentum. Pain is not often a feature, unless the contents are being squeezed by the tight opening of the sac, in which case they may be in danger of losing their blood supply (strangulating). More commonly, discomfort or aching is described, aggravated by lifting, straining, or standing for long periods of time. The discomfort can radiate down into the testicle.
Contrary to popular belief, only 10% of hernias present with a clear history of an injury event, such as a sudden strain causing pain and a swelling in the groin. More commonly, discomfort in the groin draws attention to the associated groin swelling. Sometimes the swelling causes no symptoms at all and is a chance finding, for example, when showering. This can cause concern that the swelling is due to cancer. However, swellings due to cancer do not usually disappear on lying down!
Infant hernias are congenital, i.e. are the result of a minor failure of development. They usually present soon after birth. Such issues can contribute to the development of adult hernias too. Adult hernias occur more commonly in those who have heavier or more vigorous lifestyles, but can occur in all walks of life, at any age. The vast majority of inguinal/ groin hernias (approximately 96%) occur in males, as the spermatic cord structures provide the lead point for potential herniation as they pass from the abdominal cavity through the muscle layers of the abdominal wall to the scrotum.
How does a hernia present?
A swelling becomes apparent on the abdominal wall, most commonly in the groin region, where it is known as an Inguinal hernia.
Other common types of hernias are:
Some rare types of hernias are:
The above hernias derive their names from the sites through which they protrude, or, with some of the very rare hernias, from the name of the person who first described them.
Usually hernias are more obvious when standing, as the effect of gravity encourages abdominal contents to fall into the hernia sac. Conversely, the swelling usually disappears on lying down when the contents drop back into the abdominal cavity proper. Sometimes contents become wedged in the sac, or adherent to the sac, in which case the hernia is termed irreducible. Hernia contents usually consist of either intestine or fatty tissue called the omentum, but the layer of fatty tissue present between the peritoneum, which forms the hernia sac, and the muscle layer, can also contribute significantly to the bulk of the hernia swelling. Pain is not often a feature, unless the contents are being squeezed by the tight opening of the sac, in which case they may be in danger of losing their blood supply (strangulating). More commonly, discomfort or aching is described, aggravated by lifting, straining, or standing for long periods of time.
Infant umbilical hernias are managed by paediatricians and paediatric surgeons and are not going to be discussed here. Adult umbilical hernias are often completely asymptomatic and the owner may not even be aware he/she has a hernia; generally such hernias do not require repair, but sometimes repair is requested purely for cosmetic reasons, particularly if the hernia becomes very prominent, visible through t-shirts etc. Umbilical hernias can cause discomfort or pain. Rarely, contents can strangulate.
Usually umbilical hernias are repaired through an open (non-laparoscopic) approach, via a transverse incision just above the umbilicus. The defect is closed with a strong, non-absorbable (permanent) suture. This can be supplemented by a synthetic mesh material e.g. prolene (polypropylene) placed over or deep to the closure. The operation is typically done under a general anaesthetic as a day case. Simple analgesics such as paracetamol and anti-inflammatories are all that are needed for post-operative pain control. Several days off work may be required, according to the type of work, and extremes of lifting is not advised for about 4 weeks.
Epigastric hernias are repaired using techniques very similar to those employed for umbilical hernias (see above).
Incisional hernias protrude through weaknesses of scars from previous surgery. There may be predisposition as a result of infection of the original wound, or excessive stress may have been placed on the wound before it gained adequate strength, causing it to give way. Poor surgical technique can also play a part. The size of the defect can vary from very small to massive and symptoms range from none to strangulation, which is dangerous. A prominent associated abdominal bulge can also be unsightly. Repair of larger defects can be a major technical challenge, with potential for a significant recurrent herniation rate.
On account of the high recurrence rate, I routinely place non-absorbable prolene mesh deep to the abdominal wall closure, when repairing incisional hernias. This provides added security and reduces the chance of recurrence to close to zero. Such repairs are usually done through an open surgical approach, but there is a role for laparoscopic also. This involves laparoscopic placement of mesh deep to the defect, but there is usually no accompanying closure of the fascial defect, meaning there is likely to be some persistence of the bulge postoperatively. For this reason I tend to reserve laparoscopic repairs for smaller defects, where the edges of the defect are relatively close together. Specialised forms of mesh are usually used for laparoscopic repairs, as the material is going to be in direct contact with abdominal contents (intestine). If laparoscopic repair is considered appropriate, the main advantage is reduced risk of wound infection consequences; infection in the large incision of an open repair has the potential to be a serious problem, whereas such an occurrence in small laparoscopic incisions is likely to be relatively trivial. Due to the fixation to overlying muscle required with laparoscopic repair, there is often quite significant postoperative pain associated, at times more than that caused by open repair (contrary to most other laparoscopic procedures)
Inguinal hernias: treatment
If the hernia is not causing any symptoms whatsoever, it is reasonable to consider doing nothing about it. However, it is worth remembering that the problem is a mechanical one, and the only ultimate solution is a mechanical one, i.e., surgery. The natural history for a hernia is for it to enlarge with time, sometimes gradually, sometimes very rapidly. Other factors influence decisions to go ahead with surgical repair, such as concerns that health may deteriorate in the future, making surgery more risky or more of an ordeal, or health insurance cover might be downgraded, making repair more expensive. It is also advisable to consider repair if travel to places away from medical civilisation is planned.
A hernia truss is sometimes used to control the hernia if surgery is to be avoided. A truss is a belt-like arrangement which is fitted when the hernia is “in”, usually when lying down. The belt has a pad which sits over the point where the hernia comes through the muscle wall. When the belt is tightened, the pad holds the hernia contents in. This is a useful stop-gap arrangement (literally), when surgical repair needs to be delayed for other reasons, or it might be definitive management in a very elderly and frail individual.
Surgical repair of hernias is carried out using either an open approach via an incision in the groin, or a laparoscopic technique, “keyhole” surgery, using narrow instruments and a video monitor. Laparoscopic techniques have been in use for hernia repair for well over twenty years. The open approach has been around for decades, but recent times have seen a number of modifications with improved results and reduced postoperative discomfort levels. Traditional open surgery used a suture to darn the inguinal canal, the Bassini technique. A variation called the Shouldice technique became the “gold standard” through the 1980’s, but has now been largely superseded by the Lichenstein technique, which employs a synthetic mesh to provide a tension-free repair. This is usually far more comfortable than suture techniques and is associated with low recurrence rates, around 2%. The traditional suture repairs have recurrence rates of 10% or more, with follow-up of 5+ years. Laparoscopic techniques also employ mesh, but place it on the inner aspect of the muscle layer, again in a tension-free fashion.
The lack of muscle cutting and very small incisions used to gain surgical access with the laparoscopic technique result in even less postoperative discomfort than the tension free open approaches. When properly performed, laparoscopic repair should have a recurrence rate close to zero.
Laparoscopic hernia repair
The laparoscopic technique of hernia repair avoids the large skin and muscle cut of open approaches, as well as closure of the defect with sutures under some tension. This way post-operative pain is decreased, and earlier return to discomfort-free work is possible.
The operation is done within the extraperitoneal space, which is developed from the level of the umbilicus via a small (10mm) incision. This space is between the peritoneum and muscle layers. When using the “split in a tyre casing” analogy for a hernia, the peritoneum is the inner tube and the muscle is the tyre casing. A narrow telescope (the laparoscope) is passed into the space and is connected to a television monitor which provides a magnified image of the hernia defect. Through two smaller (5mm) incisions, long narrow instruments are used to repair the defect by placing a patch of Prolene mesh over the exposed defect, fixing it in place with titanium screws mainly to the pubic bone, i.e. the patch is fixed to the tyre casing, between the inner tube and the split tyre casing. The mesh is held securely by the screws, and on account of the mechanics of the repair, early return to full normal activities and work is permissible, without fear of inducing hernia recurrence.
Laparoscopic repair is technically more demanding than traditional open approaches, but once learned, it is a very safe and reliable option.
ACC and Hernias: how does it work? (New Zealand only)
A minority of hernias result from a specific injury event. For example, pain and a lump in the groin after a sudden slip while carrying a heavy object is often cited as the cause of a hernia, in which case application can be made to the Accident Compensation Corporation (ACC) to cover the costs of repair. Certain criteria must be met for the application to be successful, in which case the costs of repair of the hernia in a private hospital will be covered in full, if it is done under a contract arrangement, or in part, if done through the alternative co-payment system.
The process is usually longer if done through the contract system because the hospital that holds the contract with ACC has a finite amount of funds which have to last the contract period. The funds also have to be distributed between other specialists performing other trauma-related operations. This means that the funds tend to be “drip-fed” to the various surgical specialists, creating a waiting list situation. There is no such restriction with the co-payment arrangement, but in this situation, the patient has to fund about 50% of the total cost, either out of their own pocket or through their private health insurer, if they have one. With co-payment, as soon as approval from ACC comes through, a date for surgery can be set. In either case, the ACC approval process usually takes about a month.
Recovery from laparoscopic hernia repair
Laparoscopic hernia repair requires a general anaesthetic, i.e. the patient is put to sleep. It is usually done as a day case and an early return to full normal activities is encouraged. Because of the mechanics involved in the repair, the repair is strong immediately and will withstand heavy physical abuse. Usually there is some discomfort to discourage this, but generally, the more activity that is undertaken, the more rapid the recovery. I encourage my patients to at least get out and have a good walk the next day, stretching and loosening the area of the repair. Simple analgesics (painkillers) such as paracetamol and anti-inflamatories are all that are required, though some do not need to take these. I encourage my patients to set activity records:
- Day 1 – Mowing lawns
- Day 1 – Full round of golf (bilateral repair)
- Day 2 – Chopping down tree with axe
- Day 2 – Pig hunting
- Day 2 – Tramping
- Day 5 – Surfing on Auckland’s West Coast
- Day 0 – Ballroom dancing
- Day 0 – Bedroom dancing
- Day 1 – Rowing single scull
- Day 2 – Fence post hole digging
- Day 2 – Deep sea fishing (landed 117kg marlin)
- Day 2 – Pall bearing
- Day 3 – 10km run
- Day 1 – Touch rugby
- Day 1 – Basketball
- Day 1 – Indoor Cricket
- Day 1 – Volleyball
- NB. In all team events the hernia team won
What sort of surgeon performs laparoscopic inguinal hernia repair?
All surgeons who have trained as General Surgeons have been taught how to repair hernias. Many, myself included, learnt prior to advent of videolaparoscopic technology. Nowadays, trainees learn videolaparoscopic skills during their surgical training. However, there is no doubt that some find the technology more difficult to use than others, and the surgeon who is skilled at open surgery is not always the best at laparoscopic procedures. Laparoscopic procedures are performed by watching the surgical target on a video monitor, rather than the target itself. This requires particular hand-eye coordination skills. In addition, the image on the screen is in two dimensions, so adjustments need to be made to allow for the lack of depth of field.
Most surgeons become competent at performing laparoscopic procedures, but, as with all skill related activities, some are more laparoscopically adept than others. Surgical temperament is also important; the impatient surgeon is much more likely to “bail out” and convert to an open approach. The above comments pertain to all laparoscopic procedures. There is an added issue with laparoscopic hernia repair in that, not only does it employ different technology to do the operation, but a totally different technique is used to effect the repair (as opposed to laparoscopic cholecystectomy to remove gallstones, which is the same operation as the open one, just a different approach). There is also new anatomy to learn, coming at the hernia defect from within, rather than from the outside. These factors create a longer learning curve, but once experience is gained, the operation is very straightforward and repeatable. Certain situations create surgical challenges, such as the overweight patient, or the patient with a very large hernia, but these are not contraindications to the approach.
I have been interested and involved in laparoscopic surgery since the advanced technology first became available for general surgical application. Its application to inguinal hernia repair was controversial at the start, but the mechanical sense behind the technique made perseverance worthwhile. Excellent statistical results combined with patient satisfaction have seen the operation become very well established, to the extent that >50% of inguinal hernia repairs in the private sector in New Zealand are now done laparoscopically. I am active in teaching the operation to other surgeons, but appreciate that it is not a surgical technique that suits all surgeons/surgical temperaments (see above).
Andrew Bowker’s experience with laparoscopic inguinal hernia repair
First laparoscopic hernia repair – 1991
Initially Transabdominal Preperitoneal (TAPP) approach, with smaller (10x6cm) mesh:
No. of repairs – (May 1995) – 240
No. of recurrences – 6 (2.5%)
Subsequently switched to Extraperitoneal (EP) approach, with larger (15x10cm) mesh:
No. of repairs (March 2017) – 7570
No. of recurrences – 16 (0.21%)
Approximately 7% of the repairs in this series have been done for recurrences following previous open hernia repair.