Hernia - what you are told, what it is and how to understand it

 

INGUINAL HERNIA

What you are told, what it is and how to understand it 

A patient reads on the British Hernia Society website that after groin hernia surgery the hernia coming back is “about 1 in 200.” A trainee cites a mesh trial: 2–3% at five years. International guidelines and registry reviews speak of population-level reoperation burden in a different register again.

Meanwhile, year after year, English Hospital Episode Statistics (HES) and Scottish SMR data show that roughly one in ten to fourteen inguinal hernia operations is coded as repair of a recurrent hernia — a proportion that has moved only slightly since the early 1990s.

None of these figures is fabricated. They answer different questions. The problem is that we quote the low ones in clinic and run the list from the high ones in theatre, without joining them up. Recurrence is discussed as if it were solved in the mesh era; recurrent groin hernia repair remains ordinary NHS work.

Study of Surgery vs. Practice of Surgery

In 2010, I wrote to The Surgeon about a Scottish paper on laparoscopic inguinal hernia and unequal access — the “postcode lottery.” Fair topic. But the same Information Services Division (ISD) tables showed recurrent repairs (OPCS T21) making up about 9% of Lothian’s inguinal workload versus 6.4% elsewhere, while the discussion leaned on literature with far lower recurrence.

I asked whether laparoscopic adoption had actually reduced, in real theatre terms, the volume of recurrent operations; whether a training centre paid a learning-curve price; and why operational figures sat so awkwardly beside published science.

The Core Disconnect: The study of surgery and the practice of surgery are simply not the same activity.

Phillips and Goldman, in the 1994 Health Care Needs Assessment volume, already used English HES for 1995/96: 6,328 recurrent repairs among 87,651 inguinal operations — 7.2%. They noted that the true recurrence rate would be higher still, because many patients never return for reoperation. The BMJ clinical review for 2001/02 England gave almost the same picture: about 7% recurrent among all inguinal activity.

Mesh became standard; laparoscopy was mandated for bilateral and recurrent cases; patient information moved toward half a percent. Yet, the administrative share of recurrent repair work did not disappear.

Understanding the 7% Metric

That 7% is not "every primary mesh repair fails at 7%." It means: among all inguinal hernia operations recorded in a year, what fraction is coded recurrent?

The mix includes:

• Late failures

• Re-recurrent groins

• Symptomatic re-presentation

• Referral patterns and coding quirks

It is nonetheless what theatres, coders, waiting lists, and trainees live with.

Region / Study	Reported Metric	Actual Workload Share / Reality
Wales (2004–2019)	~4% reoperation for recurrence with mesh	Yearly recurrent-operation shares still touched 8% in some years.
Southeastern Scotland	Rose-tinted expectations	Recurrent repair’s share of activity fell from 11.7% to 8.8% as mesh rose — improvement, not alignment with “1 in 200.”
European Registries (Herniamed)	RCT numerators	11–14% of inguinal repairs in men are recurrent cases.

HerniaSurge and society guidance rightly cite lifetime and population burden; that is consistent with administrative data, not with telling an elective primary patient their personal risk is half a percent without context.

Scotland’s nineteen-year ISD cohort (Ramsay et al.) is often cited to “prove” low modern recurrence: ~1.8% reoperation after open primary and ~3.6% after laparoscopic primary. Those are real, linked, population answers — and both can be true alongside a ~7% recurrent-operation mix on the annual list. One measures index primary failure over time; the other measures what fraction of today’s workload is recurrent repair. Conflating them is how we reassure boards while recurrent groin hernia still fills the Friday slot.

Follow-Up We Do Not Do

Trials and registries with structured follow-up produce the 1–3% band we teach for viva and consent. The NHS, especially after day-case expansion, does not routinely follow primary inguinal repairs in a way that would verify those numerators. Many recurrences are managed in primary care, tolerated, or never reoperated.

Administrative reoperation understates symptomatic failure (Phillips and Goldman said so explicitly) while trials in selected centres may overstate how uniformly good “standard mesh repair” is when dispersed across low-volume general lists.

We therefore cannot treat trial 1–3% as the verified national outcome of primary repair without follow-up. The honest signals we already have are operational:

1. Recurrent repair as a share of activity.

2. Linked reoperation after primary in national cohorts.

3. Proxies that cluster with later failure (when we bother to look).

Hernia is Still Not Its Own Specialty

I am told to blame “the system.” The system, though, is thousands of consultants for whom an inguinal hernia can be done irrespective of main subspecialty — colorectal, vascular, endocrine — with a handful of cases a year, no personal recurrence rate on the dashboard, and no obligation to report it. Planned colonic cancer resection is not distributed that way. Hernia is treated as a procedure anyone can do on the side, not a pathway where best-in-class outcomes are demanded.

That is not a claim that every colleague is careless. It is a claim about professional norms: low volume, mixed techniques, and recurrent cases on the trainee list while primaries are quoted at trial rates.

• German Routine Data (AOK): Link low hospital hernia volume to higher recurrence-operation risk.

• Shouldice Hospital (Ontario): Reports a ~1.15% reoperation rate in that institution versus ~5% in general hospitals. This is less a sermon on suture than on volume, standardized technique, and a rigorous follow-up culture — a hernia factory with audit versus a hernia slot on a general list.

The College and the British Hernia Society have pushed registry and guideline work. The gap is mandatory local reporting tied to the same OPCS codes we already bill — primary failure where we can measure it, and recurrent share of activity every trust already generates but rarely publishes beside the leaflet number.

Proxies When the Numerator is Missing

If we will not follow patients, we should at least use the associations the data already show:

• Volume: There is an inverse relationship with recurrence/reoperation in several large database studies. This is worth an audit, not moral theatre.

• Early Morbidity and Later Recurrence: Bouras et al. linked English HES and primary care (CPRD) for primaries between 1997 and 2012. A 30-day wound infection or bleeding was followed by later surgery for recurrence in 3.2% versus 1.7% without those complications ($p < 0.05$). For laparoscopic repair, the adjusted odds ratio was about 8; for open repair in the same study, the association did not reach conventional significance.

• Timing: Swedish register work and German quality-indicator reviews separate early reoperations (often haematoma, infection, pain) from later reoperation for recurrence; both matter, but they are not the same event. 30-day readmission alone is a weak long-term recurrence proxy. Repair-related early theatre return is a sharper warning flag.

Note on Chronic Pain: Chronic groin pain follows a parallel story (often ~10–15% in pooled series, far above “1 in 200”). Recurrence and pain are not interchangeable, but they share a pattern: conference outcomes are significantly kinder than primary-care reality.

What Would "Honest" Look Like?

• Publish both metrics by trust and year: reoperation/recurrence after defined primary repair where linkage allows it, and recurrent repair as a % of all inguinal activity (T21 / T20+T21).

• Stop conflating them in consent, leaflets, and board papers.

• Audit repair-related 30-day theatre return and complications as risk flags, not as substitutes for follow-up.

• Treat recurrent inguinal hernia as difficult index work — requiring specific technique, volume, and a named surgeon — not list filler.

• Treat hernia as work that deserves the same outcome discipline we expect elsewhere in elective general surgery.

The Honest Consent Conversation

Honest consent for an elective primary might sound like this:

"In good published studies of mesh repair, reoperation for recurrence is often a few per cent over five to ten years, but we do not routinely follow you to confirm that; national hospital data show repair of a previously operated groin still accounts for roughly one in ten inguinal operations; if you have a serious early problem after surgery — especially if you return to theatre — that has been linked to a higher chance of later recurrence. Your surgeon’s volume and whether this is their main work matter."

That is longer than “1 in 200.” It is also the conversation that closes the gap between study and practice.

Until we measure and publish what the list already knows, we will keep pretending recurrence has “come down” because trials improved, while HES and theatre registers tell the same stubborn story since Phillips and Goldman’s 7.2%: recurrent groin hernia repair remains ordinary NHS work, not a rarity. It remains a procedure we allow anyone to do, without demanding the outcomes we quote.

If your trust measured inguinal activity last year, what fraction was coded recurrent — and when did you last see that number beside your unit’s quoted primary recurrence rate?

References

1. British Hernia Society. Groin hernia and you. Link

2. Phillips W, Goldman M. Groin hernia. In: Stevens A, Raftery J, eds. Health Care Needs Assessment. First Series. Oxford: Radcliffe; 1994.

3. Jenkins JT, O’Dwyer PJ. Inguinal hernias. BMJ 2008;336:269–272. doi:10.1136/bmj.39450.428275.AD

4. Hemadri M. Letter: Variation of laparoscopic hernia repair in Scotland. The Surgeon 2011;9:58–59. doi:10.1016/j.surge.2010.06.010

5. Stevenson AD et al. Variation of laparoscopic hernia repair in Scotland. The Surgeon 2010;8:140–143. doi:10.1016/j.surge.2009.11.001

6. Ramsay G, Scott NW, Jansen JO. Reoperation for recurrence after laparoscopic and open inguinal hernia repair. Hernia 2020;24:793–800. doi:10.1007/s10029-019-02073-w

7. Bouras G et al. Impact of short-term complications on recurrence (linked HES/CPRD). Hernia 2017. doi:10.1007/s10029-017-1575-1

8. Köckerling F et al. Surgical risk factors for recurrence — review. Innov Surg Sci 2017. PMC6754004

9. Köckerling F et al. Hospital volume and outcome in inguinal hernia repair (AOK). Surg Endosc 2020. PMC7395912

10. HerniaSurge Group. International guidelines for groin hernia management. Hernia 2018. doi:10.1007/s10029-018-1799-9

11. Malik A et al. Reoperation for inguinal hernia repair in Ontario. Can J Surg 2016 (Shouldice ~1.15% vs ~5% general hospitals). PMC4734914

12. Atkinson HDE et al. Southeastern Scotland cohort 1985–2001. BMJ 2004;329:1315–1316. PMC534839