Inguinal hernia : optimizing surgical treatment

<p dir="ltr">Inguinal hernia is among the most common general surgical conditions, with a lifetime risk of up to 27% in men and 3% in women. Surgical repair remains the only definitive treatment, and in Sweden, approximately 16,000 inguinal hernia repairs are performed annually. Over recent decades, advances in surgical techniques—particularly the introduction of mesh-based repairs and minimally invasive approaches—have led to significantly reduced recurrence rates. Consequently, the focus of clinical and scientific interest has shifted from recurrence to optimizing patient-centered outcomes. One such key outcome is chronic postoperative inguinal pain (CPIP), a condition that can severely impact quality of life and has been reported in up to 30% of patients following hernia repair. A more elusive complication is infection involving the mesh. Fortunately, mesh infections are rare and have therefore been scarcely studied.</p><p dir="ltr">For Study I the objective was to compare long-term postoperative pain following inguinal hernia repair using two established techniques: the Lichtenstein repair under local anesthesia (LLA) and total extraperitoneal endoscopic repair (TEP) under general anesthesia. A randomized controlled trial was conducted with 384 patients (193 TEP, 191 LLA). At one year postoperatively, 97.7% completed follow- up, including the Inguinal Pain Questionnaire (IPQ). CPIP was reported in 20.7% of the TEP group compared to 33.2% in the LLA group (p = 0.007). Severe pain was reported in 4 TEP and 6 LLA patients. Pain limiting physical activity was noted in 5 TEP (2.7%) and 14 LLA (7.5%) patients (p = 0.034).</p><p dir="ltr">In Study II the aim was to assess the cost-effectiveness of LLA versus TEP for primary inguinal hernia repair in men, utilizing data from the aforementioned RCT. Health economic outcomes and sick leave data were analyzed. Among 374 patients (189 LLA, 185 TEP), median operating time was longer for LLA (70 minutes) compared to TEP (60 minutes; p < 0.001), though total time in the operating theater was shorter (LLA: 114 minutes vs. TEP: 125 minutes; p < 0.001). Median procedural costs were comparable (LLA: €2433 vs. TEP: €2395; p = 0.650). Mean sick leave duration did not differ significantly (LLA: 4.2 days vs. TEP: 6.2 days; p = 0.83).</p><p dir="ltr">The aim in Study III was to evaluate how intraoperative management of the three inguinal nerves during open anterior mesh repair influences the risk of developing CPIP. Data from 34,115 patients in the Swedish Hernia Register (2012–2017) who completed a postoperative PROM one year after surgery were analyzed. Pain that could not be ignored was reported by 25.9%, and pain interfering with daily activities by 15.7%. Multivariable ordinal regression analysis showed no significant association between identification or preservation of any of the three inguinal nerves and the risk of CPIP, after adjustment for anesthesia type, sex, age, and emergency surgery.</p><p dir="ltr">Study IV aimed to investigate the incidence, treatment, and potential risk factors for mesh infection following inguinal hernia repair. A case-control study was conducted based on 12,375 hernia repairs recorded in the Swedish Hernia Register across three hospitals between 2005 and 2020. Infectious complications were reported in 177 cases (1.43%), of which 26 (0.21%) were classified as mesh infections. These were primarily managed conservatively with antibiotics and drainage; no cases required the removal of mesh.</p><p dir="ltr">From these studies it can be concluded that TEP repair is associated with a significantly lower risk of CPIP compared to LLA, without incurring additional cost, and should therefore be considered the preferred technique for primary inguinal hernia repair. When open anterior repairs are performed, careful tissue handling is essential and pragmatic nerve resection did not increase the risk of persistent pain. Finally, mesh infections are rare and, when they do occur, are typically manageable without the need for mesh removal.</p><h3>List of scientific papers</h3><p dir="ltr">This thesis is based on the following papers, they will be referred to by their roman numerals.</p><p dir="ltr">I. Less pain one year after TEP compared to Lichtenstein using local anesthesia - data from a randomized controlled clinical trial. L. Westin, S. Wollert, M. Ljungdahl, G. Sandblom, U. Gunnarsson, U. Dahlstrand. Annals of Surgery, 2016, Volume 263, number 2: 240-3. PMID: 26079901. <a href="https://doi.org/10.1097/SLA.0000000000001289">https://doi.org/10.1097/SLA.0000000000001289</a></p><p dir="ltr">II. Health economic analysis of Total ExtraPeritoneal repair vs. Lichtenstein surgery for inguinal hernia - data from a randomized clinical trial. L. Westin, U. Gunnarsson, G. Sandblom, U. Dahlstrand. BJS Open, 2021, Volume 5, Issue 3. <a href="https://doi.org/10.1093/bjsopen/zrab026" rel="noreferrer" target="_blank">https://doi.org/10.1093/bjsopen/zrab026</a></p><p dir="ltr">III. The impact of nerve management on the risk for persistent postoperative pain one year after open anterior mesh inguinal hernia repair. L. Westin, U. Gunnarsson, G. Sandblom, U. Dahlstrand. Accepted for publication in Hernia, October 2025. [Accepted]</p><p dir="ltr">IV. Mesh infections following inguinal hernia repair - incidence, risk factors and treatment options from a Swedish cohort. L. Westin, U. Gunnarsson, G. Sandblom, U. Dahlstrand. [Manuscript]</p>