Time for a ‘bespoke’ approach to inguinal hernias – a ‘peek’ into the modern surgeon's toolkit

Inguinal hernia repairs are common, with over 40 000 repairs performed each year in Australia.1 Significant innovations in surgical techniques and prosthetic materials have led to a reduction in early recurrence rates.2, 3 The continued use of recurrence as the sole key performance indicator of surgical success, at the expense of ignoring patients' outcomes, aligns poorly with evidence-based medicine in the modern age.4, 5 The introduction of hernia-specific patient-reported outcome measures (PROM) and patient-reported experience measures (PREM) revealed significant post-operative chronic groin pain (POCGP) and reduction in quality of life (QoL) after seemingly ‘simple’ inguinal hernia surgeries.6-8 The perception that inguinal hernia repairs are simple, and can be offered to all without due consideration should no longer be acceptable. Inguinal hernias, as a disease entity, are complex, and a universal solution for all scenarios is likely not possible. To maximise patient outcomes and long-term satisfaction, the authors advocate a ‘bespoke’ patient-centric approach that takes into consideration of individual circumstances and hernia characteristics. Hernia surgery should only be recommended after the patient has been thoroughly evaluated with history taking, clinical examination and radiological imaging in selected cases (e.g., Computed Tomography with Valsalva protocol). Caution should be exercised when patients present with groin pain and an ultrasound detected ‘hernia’ without good clinical correlation, as pre-operative groin pain is a strong predictor of POCGP.9 Likewise, patients with a contralateral asymptomatic cough impulse may not necessarily benefit from bilateral concomitant surgery. In the Swedish hernia registry, only 7.4% of patients over a 12-year period of follow-up required surgery on the contralateral groin.10 The current annual incidence of bilateral hernia surgery in Australia is around 25%, suggesting potential overtreatment.1 Complexity of inguinal hernias varies. In the authors' experience, approximately 80% of inguinal hernias may be repaired with a standard surgical skill set, around 15% will require advanced specialist skill set and 5% may need multidisciplinary team input. Over 70% of inguinal hernia patients in the German hernia registry were classified as complex.11 Complex inguinal hernias are broadly appreciated to be cases with risk factors for negative outcomes. These may include irreducible inguinoscrotal hernia, or recurrent hernias with prior anterior and posterior repairs. A multidisciplinary pre-operative evaluation of patients is recommended to determine the level of care required and to preoptimize patients for surgery in these cases. Surgeons who manage inguinal hernias should be proficient in a variety of operative approaches (open, laparoscopy or robotic-assisted). In elderly comorbid patients, local anaesthesia (LA) and sedation may be preferred over general anaesthesia due to cardiovascular risks.12 In patients with obesity, a robotic approach may be safer compared to others.13 For unilateral inguinal hernias without prior repair, there is no difference between approaches, provided the surgeon has sufficient experience.12 For bilateral inguinal hernias, minimal invasive surgery (MIS) is advised.12 For recurrent hernias, approaching from the unaltered side is recommended (i.e., posterior approach if previous anterior repair). If repairs on both anterior and posterior aspects have been previously attempted, consideration should be given to a posterior robotic approach. In open repairs, techniques may be applied to facilitate dissection and preservation of tissue architecture. These may include hydro-dissection while injecting LA under external oblique muscles, and pledget dissection to mobilize the cord. Tying off nerves at risk with absorbable sutures and burying into muscle (pragmatic neurectomy); plicating redundant transversalis fascia in direct hernias; mesh fixation to the inguinal ligament with absorbable suture and use glue for tissue fixation to avoid nerve entrapment are some strategies that may be used to minimize risk of chronic pain. In MIS, the critical view of the myopectineal orifice (MPO) should be obtained by following the 9 Steps or the 10 Golden Rules.14, 15 The critical view establishes a mesh landing zone and minimizes risk of mesh folding. Nerves in the triangle of pain may be safeguarded by dissecting in the visceral compartment and preserving the nerve coverings, which may reduce risk of mesh exposure and nerve irritation. Light- to medium-weight macroporous mesh is recommended for the groin region. Synthetic mesh is preferred,12 though evidence is less robust in young patients. To minimize biofilm contamination, a no-touch technique using standard protocols should be observed. Effective porosity of mesh should be preserved when deploying mesh. Tension and folding of mesh should be prevented by creating a large pocket and handling mesh carefully, so that intense fibrosis and meshoma formation may be avoided. Known risk factors for POCGP include inappropriate indications for surgery (e.g., non-hernia causes of groin pain), poor surgical technique, iatrogenic nerve injury, incorrect mesh selection and poor mesh handling. The use of permanent sutures and heavy-weight mesh in the past to reduce hernia recurrence likely contributed to POCGP. Following hernia surgery, some patients may benefit from physiotherapy and abdominal core strengthening exercises,16 which could potentially facilitate recovery, improve patients' QoL and reduce recurrence. Patients should be counselled to return to the operating surgeon for review if pain persists beyond 12-week post-operation. Surgeons, who operate on inguinal hernias, should be skilled at diagnosing and managing of POCGP. Differential diagnoses may include non-hernia pain (e.g., hip pain), orchialgia, meshoma, neuropathic pain and hernia recurrence. Neuralgia may be confirmed utilizing a combination of pain mapping and diagnostic nerve blocks. Referral to a chronic pain specialist should be considered as a last resort after a systematic approach has been applied. Inguinal hernias are a chronic disease. Collection of PROMS and PREMS should be a mandatory requirement in any surgeon performing hernia repairs. Long-term follow-up should be centralized through a hernia registry, which will ensure ongoing monitoring of patient outcomes and auditing of mesh biodevices. A clinical quality registry is currently being piloted by the Australian and New Zealand Hernia Society across several states in Australia. With increasing complexity of inguinal hernias, it is perhaps time to consider establishing a dedicated hernia education program, with formal teaching from national and international experts. It is imperative that surgeons dealing with inguinal hernias are sufficiently skilled and proficient so that a ‘bespoke’ patient-centric approach, that takes into consideration of individual circumstances and hernia characteristics, may be provided to patients. The first author is a recipient of the Australian Government Research Training Program Scholarship and The Hospital Research Foundation Group Higher Degree by Research Top-up Scholarship. Edward Young: Project administration; resources; software; visualization; writing – original draft; writing – review and editing. Alex Karatassas: Conceptualization; methodology; supervision; validation; writing – original draft; writing – review and editing. Chrys Hensman: Conceptualization; methodology; supervision; validation; writing – original draft; writing – review and editing.