Inguinal Hernia: The anatomy of a problem - by Simon Marsh BA MB BChir MA MD FRCSEng FRCGGenSurg
With around 100,000 inguinal hernia repairs performed in the UK every year (pre Covid 19) it is one of the most common general surgical procedures, and one on which many surgeons in training cut their teeth. Post pandemic (and with the NHS experiencing unprecedented industrial disruption) waiting lists continue to rise with hernias, along with gall bladders and joint replacements representing the “big three” where long delays are now occurring.
But even before the pandemic hernia surgery was already effectively being rationed (although no one was prepared to utter the “R” word officially). By 2018 two thirds of Clinical Commissioning Groups (CCGs, as they were then) had placed restrictions on hernia surgery, demanding evidence of irreducibility, month on month increase in size or the presence of pain sufficient to affect daily activities or preclude work. In one CCG obese patients were automatically declined surgery and almost all refused to fund surgery for what were termed “minimally symptomatic hernias”. In July 2018 the British Hernia Society and the Royal College of Surgeons published a review of access to hernia surgery in England entitled “A dangerous waiting game?” highlighting the potential risks of these strategies that sought to limit hernia surgery for financial reasons.
Not only is there now a problem with getting hernias operated upon, but there is also controversy about which technique should be used. At his point a little history might be helpful. Whilst it’s not possible to pay tribute to all those involved in the evolution of hernia repair there are a few individuals and developments that deserve recognition.
Edoardo Bassini (1844-1924), an Italian surgeon, described a technique of inguinal hernia repair that relied on restoring the normal anatomy of the inguinal canal, after excising the hernia sac. Between 1883 and 1889 he performed 262 operations with 7 recurrences (2.7%), which compares extremely favourably with an all-comer’s recurrence rate now of around 5%, according to the Royal College of Surgeons.
Mass hernia repair is credited to the establishment of the Shouldice Clinic in 1945. Edward Earle Shouldice (1890-1965) developed his technique (really just a modification of the Bassini repair) during the Second World War to “help” those men that couldn’t enlist because they had a hernia. In 1953 he moved the clinic to Thornhill, Ontario. Using their team of specialist surgeons and still relying largely on the anatomical “Shouldice Repair” they report a recurrence rate of less than 1%. This was the technique (with minor variations) by which nearly all inguinal hernias were repaired until the mid-1990s.
In 1987 Irving Lichtenstein (1920-2000) published his series of 6321 patients in whom he had repaired their hernias with a polypropylene mesh and claimed a recurrence rate of just 0.7%. He labelled his technique “tensionless” and by the middle of the 1990s it had become adopted as the most common technique for repairing hernias in the UK. It was claimed to be an easier technique to perform as no detailed anatomical knowledge was required, and so more straightforward for an inexperienced surgeon. It also claimed to produce lower initial discomfort and have a lower recurrence rate, but neither of these claims has been substantiated. Finally, it was supposed to be easy to teach to others, cheap and could be done under local anaesthetic.
And then, with the rise of laparoscopic surgery, there erupted a plethora of possible techniques, each boasting their superiority over the others. At this stage it is probably worth summarising the various techniques available. Basically, the distinction was between the open and the laparoscopic methods. Open repair can be done with a mesh patch (Lichtenstein) placed anteriorly on the muscles, or with a mesh plug placed posteriorly (pre-peritoneally) behind the muscles (or both) or, anatomically with no mesh (Basssini, Shouldice type repair). Laparoscopic repair always involves the use of a mesh, and the two main techniques are TAPP (trans-abdominal pre-peritoneal) and the TEP (totally extra peritoneal). I think it’s fair to say that there was considerable disagreement between the open and laparoscopic proponents as to which was best.
Getting to the truth can be problematic and I would like to introduce the “Newton-Bendavid First Law of statistics”. Isaac Newton (I hope) needs no introduction. Robert Bendavid was head of the Shouldice Clinic. It was my pleasure to know him for many years and to share podia with him. He died in 2019. The law states that: “For every statistic quoted in the surgical literature there will be an equal and opposite statistic reported in the same literature”. In other words, you can pick and choose your statistics to fit your opinion. Having said that, here are a few regarding laparoscopic hernia repairs. In the early days there were concerns about the high cost. Others reported on the longer theatre time and the potential for more serious complications. Some found no difference in chronic pain or recurrence compared with open repair. A meta-analysis in 2002 concluded that an open technique using a pre-peritoneal plug was the optimal technique.
However you look at it, the potential complications in laparoscopic repair are more serious (for example, out of field injuries, gas embolism, inadvertent organ ligation etc.), although they are mostly rare. Some are not so rare. Dysejaculation is reported as 100 times greater after laparoscopic repair (3.1%) whilst the rate of severe, chronic pain seems to sit around 13%. Also, learning a laparoscopic technique has a much longer learning curve, requiring at least 200 cases and possibly up to 1000. There is no doubt that in most hands it takes longer (up to twice as long) and it is interesting how often a unilateral laparoscopic hernia repair ends up being bilateral due to the findings of a small, asymptomatic hernia on the other side. Laparoscopic surgery has acquired the sobriquet of being “minimally invasive” and, indeed, the individual port scars are small. However, for an inguinal hernia repair the area of laparoscopic dissection required can be 3 times larger than in an open repair and the volume up to 9 times greater. Not so minimal really. And it is interesting to note that the proportion of hernias repaired laparoscopically in the UK remains under 15%, similar to other European countries (Sweden 12%, the Netherlands 16%) and the USA and Canada (8% and 12.5% respectively). All this led Jonathon Glass, Consultant Surgeon at Guys and St. Thomas’ Hospital NHS Foundation Trust, to write, in an article for the Royal college of Surgeons (in 2023), that “laparoscopic hernia repair has, for the most part, come and gone” as it has never been able to live up to the initial hype.
And then we have the spectre of mesh related pain that taints not only laparoscopic repair but also the Lichtenstein technique. What started as a potential problem with certain gynaecological procedures has spread to mesh hernia repairs, both laparoscopic and open. Depending on the study, the incidence of persistent pain after mesh repair varies from 3 to 78%, with the European Hernia Society stating that the incidence of severe, chronic pain is 10-11%. Affected patients are seeking mesh removal, a difficult procedure after open repair, and almost impossible after a laparoscopic repair. Data from the Shouldice Clinic, following mesh explant procedures, have highlighted mesh degradation, neo-innervation and nerve growth into the mesh and erosion of anatomical structures as factors that may all contribute to the pain. Such has been the clamour that the Royal College of Surgeons has proclaimed that “there is a mesh free alternative for patients with groin hernias, which some surgeons have called for the NHS to teach its staff, so patients can have a choice”. It does seem that the Royal College of Surgeons is concerned about any mesh-based technique. And so, as we have come full circle.
Offering an informed choice is only right but the concern remains that because the current generation of surgeons may have only learnt the Lichtenstein repair or laparoscopic techniques, the expertise to perform non-mesh, anatomical repairs is being lost in the same way that no-one alive now can reproduce a Stradivarius violin. So, where are the teachers going to come from? At 108 Harley Street, where the detailed knowledge of the anatomy of the groin plays such a fundamental role in the repair of Gilmore’s Groin (a musculo-tendinous injury, usually in young male athletes) we are one of the few places left that can still offer non-mesh inguinal hernia repair and we are pleased to support the NHS in inguinal hernia surgery.
Content provided by Simon Marsh BA MB BChir MA MD FRCSEng FRCSGenSurg
Surgical Director, The Gilmore Groin and Hernia Clinic, 108 Harley Street
Consultant Surgeon, East Suffolk and North Essex NHS Foundation Trust
For more information please visit 108harleystreet.co.uk or call 0207 563 1234.
Nourish Care has announced its partnership with workforce management solution, Workforce.com.
