Lightweight versus heavyweight in inguinal hernia repair: a meta-analysis. Hernia. 2012;16:529-539. [PMID: 22689249 DOI: 10.1007/s10029-012-0928-z]

Is mesh pore size in polypropylene meshes associated with the outcome in Lichtenstein inguinal hernia repair: a registry-based analysis of 22,141 patients

INTRODUCTION

Experimental data show that large-pored meshes reduce foreign body reaction, inflammation and scar bridging and thus improve mesh integration. However, clinical data on the effect of mesh porosity on the outcome of hernioplasty are limited. This study investigated the relation of pore size in polypropylene meshes to the outcome of Lichtenstein inguinal hernioplasty using data from the Herniamed registry.

METHODS

This analysis of data from the Herniamed registry evaluated perioperative and 1-year follow-up outcomes in patients undergoing elective, primary, unilateral Lichtenstein inguinal hernia repair using polypropylene meshes. Patients operated with a non-polypropylene mesh or a polypropylene mesh with absorbable components were excluded. Polypropylene meshes with a pore size of 1.0 × 1.0 mm or less were defined as small-pored meshes, while a pore size of more than 1.0 × 1.0 mm was considered large-pored. Unadjusted analyses and multivariable analyses were performed to investigate the relation of pore size of polypropylene meshes, patient and surgical characteristics to the outcome parameters.

RESULTS

Data from 22,141 patients were analyzed, of which 6853 (31%) were operated on with a small-pore polypropylene mesh and 15,288 (69%) with a large-pore polypropylene mesh. No association of mesh pore size with intraoperative, general or postoperative complications, recurrence rate or pain requiring treatment was found at 1-year follow-up. A lower risk of complication-related reoperation tended to be associated with small-pore size (p = 0.086). Furthermore, small-pore mesh repair was associated with a lower risk of pain at rest and pain on exertion at 1-year follow-up.

CONCLUSION

The present study could not demonstrate an advantage of large-pore polypropylene meshes for the outcome of Lichtenstein inguinal hernioplasty.

Perioperative Risk Factors for Persistent Postsurgical Pain After Inguinal Hernia Repair: Systematic Review and Meta-Analysis

Persistent postsurgical pain (PPSP) is one of the most bothersome and disabling long-term complications after inguinal hernia repair surgery. Understanding perioperative risk factors that contribute to PPSP can help identify high-risk patients and develop risk-mitigation approaches. The objective of this study was to systematically review and meta-analyze risk factors that contribute to PPSP after inguinal hernia repair. The literature search resulted in 303 papers included in this review, 140 of which were used for meta-analyses. Our results suggest that younger age, female sex, preoperative pain, recurrent hernia, postoperative complications, and postoperative pain are associated with a higher risk of PPSP. Laparoscopic techniques reduce the PPSP occurrence compared to anterior techniques such as Lichtenstein repair, and tissue-suture techniques such as Shouldice repair. The use of fibrin glue for mesh fixation was consistently associated with lower PPSP rates compared to tacks, staples, and sutures. Considerable variability was observed with PPSP assessment and reporting methodology in terms of study design, follow-up timing, clarity of pain definition, as well as pain intensity or interference threshold. High or moderate risk of bias in at least one domain was noted in >75% of studies. These may limit the generalizability of our results. Future studies should assess and report comprehensive preoperative and perioperative risk factors for PPSP adjusted for confounding factors, and develop risk-prediction models to drive stratified PPSP-mitigation trials and personalized clinical decision-making. PERSPECTIVE: This systematic review and meta-analysis summarizes the current evidence on risk factors for persistent pain after inguinal hernia repair. The findings can help identify patients at risk and test personalized risk-mitigation approaches to prevent pain. PROSPERO REGISTRATION: htttps://www.crd.york.ac.uk/prospero/display_record.php?RecordID=154663.

An international survey of 1014 hernia surgeons: outcome of GLACIER (global practice of inguinal hernia repair) study

INTRODUCTION

The practice of inguinal hernia repair varies internationally. The global practice of inguinal hernia repair study (GLACIER) aimed to capture these variations in open, laparoscopic, and robotic inguinal hernia repair.

METHODS

A questionnaire-based survey was created on a web-based platform, and the link was shared on various social media platforms, personal e-mail network of authors, and e-mails to members of the endorsed organisations, which include British Hernia Society (BHS), The Upper Gastrointestinal Surgical Society (TUGSS), and Abdominal Core Health Quality Collaborative (ACHQC).

RESULTS

A total of 1014 surgeons from 81 countries completed the survey. Open and laparoscopic approaches were preferred by 43% and 47% of participants, respectively. Transabdominal pre-peritoneal repair (TAPP) was the favoured minimally invasive approach. Bilateral and recurrent hernia following previous open repair were the most common indications for a minimally invasive procedure. Ninety-eight percent of the surgeons preferred repair with a mesh, and synthetic monofilament lightweight mesh with large pores was the most common choice. Lichtenstein repair was the most favoured open mesh repair technique (90%), while Shouldice repair was the favoured non-mesh repair technique. The risk of chronic groin pain was quoted as 5% after open repair and 1% after minimally invasive repair. Only 10% of surgeons preferred to perform an open repair using local anaesthesia.

CONCLUSION

This survey identified similarities and variations in practice internationally and some discrepancies in inguinal hernia repair compared to best practice guidelines, such as low rates of repair using local anaesthesia and the use of lightweight mesh for minimally invasive repair. It also identifies several key areas for future research, such as incidence, risk factors, and management of chronic groin pain after hernia surgery and the clinical and cost-effectiveness of robotic hernia surgery.

Fascinating history of groin hernias: Comprehensive recognition of anatomy, classic considerations for herniorrhaphy, and current controversies in hernioplasty

Groin hernias include indirect inguinal, direct inguinal, femoral, obturator, and supravesical hernias. Here, we summarize historical turning points, anatomical recognition and surgical repairs. Groin hernias have a fascinating history in the fields of anatomy and surgery. The concept of tension-free repair is generally accepted among clinicians. Surgical repair with mesh is categorized as hernioplasty, while classic repair without mesh is considered herniorrhaphy. Although various surgical approaches have been developed, the surgical technique should be carefully chosen for each patient. Regarding as interesting history, crucial anatomy and important surgeries in the field of groin hernia, we here summarized them in detail, respectively. Points of debate are also reviewed; important points are shown using illustrations and schemas. We hope this systematic review is surgical guide for general surgeons including residents. Both a skillful technique and anatomical knowledge are indispensable for successful hernia surgery in the groin.

Mechanical properties of warp-knitted hernia repair mesh with various boundary conditions

In this paper, two most representative hernia repair meshes were prepared with 0.15 mm polypropylene monofilaments via warp knitting technology, and their mechanical properties were tested in various aspects. Meanwhile, a focused investigation of the boundary conditions between the sutures and the mesh was simulated in several directions innovatively. The results revealed that the hernia repair mesh with different structures has different mechanical properties, and the mechanical properties of standard hernia repair mesh were superior to that of lightweight hernia repair mesh. In order to reduce foreign body sensation and postoperative adverse reactions significantly, the lightweight hernia repair mesh may be preferred. At the same time, the mesh should be placed in the proper direction to comply with the anisotropy of abdominal wall during operation. The area where the hernia mesh is in contact with the sutures was vulnerable to damage. The curved or wrinkled area of the hernia repair mesh increases with the increase of load, which may lead to poor tissue growth, a strong inflammatory response, and even the recurrence of the hernia. Therefore, the hernia repair meshes with different structures may require unique suture techniques. And they also should be further treated prior to implantation. This study provides a theoretical basis for development, utilization and improvement of meshes. Further research will focus on the biomechanical properties of the mesh after implantation in vivo studies.

Patient-reported chronic pain after open inguinal hernia repair with lightweight or heavyweight mesh: a prospective, patient-reported outcomes study

BACKGROUND

Chronic pain after groin hernia repair is a significant problem, and it is unclear whether or not lightweight meshes help. This national register-based study investigated whether patients who underwent open anterior mesh inguinal hernia repair with lightweight mesh had less chronic pain than those who had hernia repair with heavyweight mesh.

METHODS

All patients registered in the Swedish Hernia Register between September 2012 and October 2016 were asked to complete a questionnaire assessing patient-reported outcome measures 1 year after surgery. The present study examined open anterior repair with mesh sutured in place with non-absorbable sutures in male patients only. The primary endpoint, chronic pain, was defined as pain present in the past week that could not be ignored and interfered with concentration (on chores) and daily activities.

RESULTS

In total, 23 259 male patients provided data for analysis (response rate 70·6 per cent). Rates of chronic pain after repairs using regular polypropylene lightweight mesh, composite (poliglecaprone-25) polypropylene lightweight mesh and polypropylene heavyweight mesh were 15·8, 15·6 and 16·2 per cent respectively. Adjusted multiple logistic regression analysis showed no significant differences between regular (odds ratio (OR) 0·98, 95 per cent c.i. 0·90 to 1·06) or composite (OR 0·95, 0·86 to 1·04) lightweight mesh versus heavyweight mesh. The most striking risk factor for chronic pain was young age; 19·4 per cent of patients aged less than 50 years experienced pain 1 year after hernia repair (OR 1·43, 1·29 to 1·60).

CONCLUSION

Patient-reported chronic pain 1 year after open mesh repair of inguinal hernia was common, particularly in young men. The risk of developing chronic pain was not influenced by the type of mesh.

Chronic postoperative inguinal pain: A narrative review

Inguinodynia or chronic postoperative inguinal pain is a growing problem between patients who undergo surgical repair of an inguinal hernia. The change in results measurement proposed by many authors towards Patient Reported Outcome Measurement has underlined the importance of chronic postoperative inguinal pain, because of the great limitations in everyday life and the huge socioeconomic impact that it causes. In this article a narrative review of the available literature in PUBMED, EMBASE and Cochrane Library is performed and the most relevant aspects about epidemiology, etiology prevention, diagnosis and treatment of chronic postoperative inguinal pain are discussed. A new management algorithm is also proposed. The variability in its incidence and clinical presentation makes diagnosis of chronic postoperative inguinal pain a very challenging issue. There is no standardized therapy and an adequate etiological diagnosis is key point for a successful treatment. There are many treatment options that have to be sequentially used and adjusted to each patient and their clinical features.

Comparing large pore lightweight mesh versus small pore heavyweight mesh in open mesh plug repair of primary and recurrent unilateral inguinal hernia - A questionnaire study for a retrospective analysis of a cohort of elective groin hernia patients using propensity score matching

PURPOSE

For surgical treatment of inguinal hernia, large-pore, lightweight mesh has been shown to offer advantages over small-pore, heavyweight options in terms of chronic post-operative inguinal pain, but without the disadvantage of having to deal with an increased recurrence rate. Limited data are available for the mesh plug repair technique. Therefore, the primary aim of this study is to compare large-pore, lightweight mesh versus small-pore, heavyweight mesh for mesh plug repair with regard to chronic pain and recurrences in elective primary unilateral hernias. In addition, we report our experience in repairing recurrent hernias.

METHODS

Using a modified version of the questionnaire from the Danish Hernia Registry, two groups were surveyed: elective primary unilateral hernias and recurrent unilateral hernias. In both groups small-pore, heavyweight mesh (HWM) and lightweight, large-pore mesh (LWM) were compared with respect to chronic pain and recurrences. Propensity score matching (PS) was carried out on a pool of 1,782 patients. Effect sizes were assessed by using Cohen's d and Cramer's V.

RESULTS

If the questionnaire item 'lump/swelling' is considered as a surrogate for recurrence (clinically verified in our study), the results in primary hernias after HWM show a 6.0% recurrence rate and 7.3% after LWM (p = 0.487) with a mean follow up of 31,3 months in HWM and 29,2 months in LWM respectively. The questionnaire item 'pain impacting on work/leisure activities' was answered with Yes in 11.5% following HWM and in 10.5% following LWM (p = 0.665). After the evaluation of the overall surgical results, we did not find differences. Comparing primary and recurrent hernia repair we found below small effect size differences with respect to the items of the questionnaire.

CONCLUSIONS

The use of LWM in repairing elective unilateral primary hernias by the mesh plug technique does not result in less chronic pain and more recurrences when compared with HWM. Recurrent hernias repaired by the mesh plug technique may have same outcomes like in primary hernia repair when considering the magnitude of effect sizes.

Predictive factors of post-laparoscopic inguinal hernia acute and chronic pain: prospective follow-up of 807 patients from a single experienced surgeon

INTRODUCTION

Convalescence after hernia repair is one of the main focuses for hernia surgeons. We analyzed our prospectively collected data to identify possible predictive factors for post-operative acute and chronic pain.

MATERIALS AND METHODS

We prospectively collected the demographic data and peri-operative findings. Post-operative acute pain was evaluated with Visual Analog Pain Scale. The chronic pain (pain persists for > 6 months since operation) was also recorded.

RESULTS

From June 2008 to August 2018, there were 807 patients with 1029 sites of inguinal hernia enrolled in our analysis. Pain before operation was associated with the severity of acute pain on OP (operation) day, POD 1 (post-operative day 1), and POD 7 (post-operative day 7). Younger patients had significantly higher post-operative acute pain on OP day, POD 1, and POD 7. The staple mesh fixation method resulted in a higher pain score at OP day and POD 1. The predictive factors for chronic pain were sex (female), young age (< 65 years), having no past history of hypertension, pain before operation, and mesh material.

CONCLUSION

A younger age and inguinal pain before operation were the main predictive factors for higher post-operative pain. Younger patients, females, having inguinal pain before surgery, and using heavy weight mesh have a higher risk of chronic pain.

Outcomes of carotid endarterectomy in the Vascular Quality Initiative based on patch type

OBJECTIVE

The Vascular Quality Initiative (VQI) is the largest registry of vascular surgical procedures and as such is capable of distinguishing small but important differences in outcomes. The goal of this study was to determine the outcomes of carotid endarterectomy (CEA) based on patch type, including bovine pericardium, autogenous vein, polytetrafluoroethylene (PTFE), and Dacron.

METHODS

All primary CEAs performed with primary repair and patching (n = 70,987) within the VQI were retrospectively analyzed. Reoperative CEA and combined CEA and coronary artery bypass were excluded. Rates of any postoperative neurologic event, return to the operating room (bleeding, neurologic event, or wound complication), and restenosis (>50% and >80%) at 1-year follow-up were primary outcomes. Rates were compared by patch type using χ² and Bonferroni analysis. Multivariate hierarchical logistic regression models were used to predict end points of postoperative neurologic event, return to the operating room, and 1-year restenosis.

RESULTS

During the period of study, 2003 to 2017, there were 70,987 CEAs entered into the VQI registry. Bovine pericardium was the patch material with the highest frequency of use (n = 51,480), followed by Dacron (n = 12,356), vein (n = 1460), and PTFE (n = 1638). Bovine pericardium, vein, and Dacron had lower rates of postoperative neurologic events compared with PTFE or primary repair. Bovine pericardium had the lowest rate of restenosis at 1 year. By multivariate analysis, bovine pericardium (odds ratio [OR], 0.70; 95% confidence interval [CI], 0.56-0.89) and protamine use (OR, 0.74; 95% CI, 0.60-0.91) were associated with a lower incidence of return to the operating room. The use of Dacron, vein, and PTFE patches was not significantly different from the reference of primary closure. Multivariate analysis of postoperative neurologic events revealed that bovine pericardium (OR, 0.59; CI, 0.48-0.72) and Dacron (OR, 0.56; CI, 0.43-0.72) were associated with lower incidence of stroke or transient ischemic attack, whereas vein and PTFE were no different from primary closure. Bovine pericardium (OR, 0.57; CI, 0.44-0.75), Dacron (OR, 0.70; CI, 0.50-0.98), vein (OR, 0.72; CI, 0.53-0.98), and never smoking (OR, 0.87; CI, 0.78-0.96) were associated with a lower incidence of restenosis at 1 year by multivariate analysis.

CONCLUSIONS

Bovine pericardium has superior outcomes both postoperatively and at 1 year compared with other patch materials. The large volume of patient data contained in the VQI makes it possible to compare outcomes that have small but meaningful differences.

Lightweight Versus Heavyweight Mesh in Laparoscopic Inguinal Hernia Repair: An Updated Systematic Review and Meta-Analysis of Randomized Trials

Background: There is no consensus on whether lightweight mesh (LWM) is better than heavyweight mesh (HWM) in laparoscopic inguinal hernia repair (LIHR). This study aims to update the previous reviews and to analyze present randomized controlled studies comparing LWM versus HWM in LIHR systematically. Methods: We searched PubMed, Embase, and Cochrane Library for randomized controlled trials (RCTs), which compared LWM with HWM in adults with LIHR. All eligible data of outcomes were quantitatively analyzed using Revman 5.3 software or qualitatively described. The outcomes included chronic pain, moderate-severe chronic pain, recurrence, foreign body sensation, influence on sexual life and male fertility (pain with ejaculation, testicular pain, etc.). Results: We included 12 RCTs that analyzed 3092 hernias. The difference between LWM and HWM groups at any follow-up time was not significant in chronic pain and foreign body sensation. Compared with HWM group, patients in LWM group had a similar risk of postoperative moderate-severe chronic pain at 3 and 12 months follow-up, a slightly increased risk of developing moderate-severe chronic pain at >12 months follow-up (risk ratio [RR] = 3.20, 95% confidence interval [CI] 1.05-9.75, P = .04), and a higher risk of recurrence rate (RR = 2.28, 95% CI 1.17-4.44, P = .02). At long-term follow-up, the influences of LWM and HWM on sexual life and male fertility were comparable. Conclusion: LWMs do not show advantages in chronic pain, foreign body sensation as well as the influence on sexual life and male fertility, and may increase hernia recurrence rates for LIHR. In addition, a higher incremental cost and lower incremental effect of LWMs make conventional HWMs preferred choice for LIHR.

Laparoscopic Approach to Inguinal Disruption in Athletes: a Retrospective 13-Year Analysis of 198 Patients in a Single-Surgeon Setting

Background

Inguinal disruption (ID) is a condition of chronic groin pain affecting mainly athletes. ID cannot be defined as a true hernia. Pathogenesis is multifactorial due to repetitive and excessive forces applied to the inguino-pelvic region. Examination reveals tenderness to palpation of the inguinal region. Differential diagnosis is challenging; imaging is helpful for excluding other pathologies. Surgery is the treatment of choice when conservative treatment fails. Primary aim of the study was to evaluate the time to return to full sport activity after transabdominal preperitoneal patch plasty (TAPP) technique in ID. Secondary aim was to evaluate the postoperative complication rate both in the immediate post-operative time and in 1 year follow-up and to verify the relapse rate after surgery. In this study, we consider time to return to full sport activity as the time needed to return to pre-injury sport activity.

Results

A retrospective study is reported by evaluating 198 cases of ID from a single surgeon experience. All patients failed a previous conservative treatment. All cases were treated with the TAPP approach. Time to return to full sport activity was 4 weeks for 94.4% of patients, with a total of 98.5% of active patients at 9 months. Post-operative inguinal pain was the main complication (9.1%). On 13 years follow-up, we report a recurrence rate of 2.5%.

Conclusions

Current management algorithm for ID, in professional athletes, supports the role of surgery after at least 2 months of conservative treatment. Recently, the role of surgery has been highlighted for a definitive treatment and a faster full recovery to sport activity, especially for elite professional athletes. In our opinion, laparoscopic surgery is the mainstay for non-responsive ID treatment. We present a long-term retrospective evaluation of a wide cohort of professional athletes diagnosed and treated in a systematic way.

[Endoscopic surgery and laparoscopy are new insights of evolution of inguinal hernia repair (in Russian only)]

This article is devoted to general and particular problems of inguinal hernia repair through the analysis of statistical data and comparison of advantages and disadvantages of various methods of inguinal hernia repair. Particular attention is paid to the analysis of current options of mesh implant fixing during endoscopic hernia repair: TAPP, TER, e-TER. Long-term outcomes are essential to determine surgical technique. The authors consider that careful adherence to the basic principles of minimally invasive surgery can reduce the incidence of complications, recurrences and chronic pain syndrome after inguinal hernia repair. The main advantages of current surgical technologies are accelerated rehabilitation, earlier restoration of social activity, improvement of the quality of life.

Polypropylene mesh and systemic side effects in inguinal hernia repair: current evidence

INTRODUCTION

Increasing awareness and regulatory body attention is directed towards the insertion of synthetic material for a variety of surgical procedures. This review aims to assess current evidence regarding systemic and auto-immune effects of polypropylene mesh insertion in hernia repair.

METHODS

The electronic literature on systemic and auto-immune effects associated with mesh insertion was examined.

RESULTS

Foreign body reaction following mesh implantation initiates an acute inflammatory cellular response. Involved markers such as IL-1, IL-6, IL-10 and fibrinogen are increased in circulation in the presence of mesh but return to normal at 7 days post operatively. Oxidative degradation of implanted mesh is likely, but no evidence exists to support systemic absorption or resulting disease effects. Variable cytokine production in healthy hosts leading to unpredictable or overwhelming response to implanted biomaterial warrants further investigation. Clinical studies show no associated long-term systemic effects with mesh.

CONCLUSION

To date, there remains no evidence to link polypropylene mesh and systemic or auto-immune symptoms. Based on current evidence, the use of polypropylene mesh is supported.

Titanium-coated mesh versus standard polypropylene mesh in laparoscopic inguinal hernia repair: a prospective, randomized, controlled clinical trial

OBJECTIVE

We aimed to compare the clinical outcome of titanium-coated mesh and polypropylene mesh in laparoscopic inguinal hernia repair.

METHODS

A total of 102 patients who received laparoscopic inguinal hernia repair in January-June 2016 in Beijing Chao-Yang Hospital were enrolled in this study. Patients were randomly divided into two groups, receiving either titanium-coated mesh (n = 50) or standard polypropylene mesh (n = 52). Multiple clinical parameters were collected and analyzed, including clinical manifestations, operative time, intraoperative blood loss, hospital stay, hospital cost, recovery time, and postoperative complications.

RESULTS

All procedures were completed. A statistical difference between two groups was not identified in regards to operative time, intraoperative blood loss, hospital stay, and recovery time (P > 0.05). Three cases with seroma and 15 with foreign body sensation were reported in the titanium-coated mesh group; 9 cases with seroma and 17 with foreign body sensation were reported in the standard polypropylene mesh group. There was no significant difference in the incidence of seroma and/or foreign body sensation. A lower hospital cost but longer recovery period was documented in the standard polypropylene mesh group (P < 0.05). No recurrence, infection or chronic pain was observed during 1-year follow-up in both groups.

CONCLUSION

Titanium-coated mesh possesses comparable clinical qualities as the standard polypropylene mesh but with a shorter recovery period. Therefore, this mesh is promising for clinical practice though the cost is higher than the standard polypropylene mesh.

Lower recurrence rate with heavyweight mesh compared to lightweight mesh in laparoscopic totally extra-peritoneal (TEP) repair of groin hernia: a nationwide population-based register study

Purpose

Lightweight meshes (LWM) have shown benefits compared to heavyweight meshes (HWM) in terms of less postoperative pain and stiffness in open inguinal hernia repair. It appears to have similar advantages also in TEP, but concerns exist if it may be associated with higher recurrence rates. The aim of the study was to compare reoperation rate for recurrence of LWM to HWM in laparoscopic totally extra-peritoneal (TEP) repair.

Methods

All groin hernias operated on with TEP between 1 January 2005 and 31 December 2013 at surgical units participating in The Swedish Hernia Register were eligible. Data included clinically important hernia variables. Primary endpoint was reoperation for recurrence. Median follow-up time was 6.1 years (0–11.5) with minimum 2.5 years postoperatively.

Results

In total, 13,839 repairs were included for statistical analysis and 491 were re-operated for recurrence. Multivariate analysis demonstrated significantly increased risk of reoperation for recurrence in LWM 4.0% (HR 1.56, P < 0.001) compared to HWM 3.2%. This was most evident in direct hernias (HR 1.75, P < 0.001) and in hernia repairs with a defect > 3 cm (HR 1.54, P < 0.021). The risk of recurrence with use of LWM in indirect hernias and in hernia repairs with a defect < 1.5 cm was more comparable to HWM.

Conclusions

Lightweight meshes were associated with an increased risk of reoperation for recurrence compared to HWM. While direct hernias and larger hernia defects may benefit from HWM to avoid increased recurrence rates, LWM is recommended to be used in indirect and smaller hernia defects in TEP repair.

Defining the characteristics of certified hernia centers in Italy: The Italian society of hernia and abdominal wall surgery workgroup consensus on systematic reviews of the best available evidences

BACKGROUND

The terms "Hernia Center" (HC) and Hernia Surgeon" (HS) have gained more and more popularity in recent years. Nevertheless, there is lack of protocols and methods for certification of their activities and results. The Italian Society of Hernia and Abdominal Wall Surgery proposes a method for different levels of certification.

METHODS

The national board created a commission, with the task to define principles and structure of an accreditation program. The discussion of each topic was preceded by a Systematic Review, according to PRISMA Guidelines and Methodology. In case of lack or inadequate data from literature, the parameter was fixed trough a Commission discussion.

RESULTS

The Commission defined a certification process including: "FLC - First level Certification": restricted to single surgeon, it is given under request and proof of a formal completion of the learning curve process for the basic procedures and an adequate year volume of operations. "Second level certification": Referral Center for Abdominal Wall Surgery. It is a public or private structure run by at least two already certified and confirmed FLC surgeons. "Third level certification": High Specialization Center for Abdominal Wall Surgery. It is a public or private structure, already confirmed as Referral Centers, run by at least three surgeons (two certified and confirmed with FLC and one research fellow in abdominal wall surgery). Both levels of certification have to meet the Surgical Requirements and facilities criteria fixed by the Commission.

CONCLUSION

The creation of different types of Hernia Centers is directed to create two different entities offering the same surgical quality with separate mission: the Referral Center being more dedicated to clinical and surgical activity and High Specialization Centers being more directed to scientific tasks.

An easier Lichtenstein hernioplasty

BACKGROUND

The Lichtenstein technique is used worldwide because of its rapid learning curve, good results and low recurrence rates. In this approach, a lateral tie-shaped incision is made on the mesh, involving the spermatic funiculus and thus correcting the deep inguinal ring defect by narrowing it. The lateral tie, however, does not prevent the wrinkling of the upper portion of the mesh that is caused by the arched shape of the inguinal ligament, where the lower edge of the prosthesis is sutured.

OBJECTIVE

To describe a variation of the Lichtenstein technique that is easy to perform, maintains the advantages and prevents wrinkling of the mesh and allows for better mesh accommodation in the inguinal region.

METHODS

The main feature of this approach is to cut the mesh vertically and to make the tie over the spermatic cord by overlapping the two resulting portions without wrinkling them. The final appearance is clearly more anatomical, allowing the mesh to be perfectly adapted for each patient.

RESULTS

We operated on consecutive patients using this approach for more than 5 years. There have been no recurrences or specific mesh complications during follow-up, and the surgical aspect of this technique was clearly more anatomical.

CONCLUSIONS

This method appears to be easier to perform and the surgical aspects of the technique are more anatomical for the patient.

Mechanical behavior of surgical meshes for abdominal wall repair: In vivo versus biaxial characterization

Despite the widespread use of synthetic meshes in the surgical treatment of the hernia pathology, the election criteria of a suitable mesh for specific patient continues to be uncertain. Thus, in this work, we propose a methodology to determine in advance potential disadvantages on the use of certain meshes based on the patient-specific abdominal geometry and the mechanical features of the certain meshes. To that purpose, we have first characterized the mechanical behavior of four synthetic meshes through biaxial tests. Secondly, two of these meshes were implanted in several New Zealand rabbits with a total defect previously created on the center of the abdominal wall. After the surgical procedure, specimen were subjected to in vivo pneumoperitoneum tests to determine the immediate post-surgical response of those meshes after implanted in a healthy specimen. Experimental performance was recorded by a stereo rig with the aim of obtaining quantitative information about the pressure-displacement relation of the abdominal wall. Finally, following the procedure presented in prior works (Simón-Allué et al., 2015, 2017), a finite element model was reconstructed from the experimental measurements and tests were computationally reproduced for the healthy and herniated cases. Simulations were compared and validated with the in vivo behavior and results were given along the abdominal wall in terms of displacements, stresses and strain. Mechanical characterization of the meshes revealed Surgipro^TM as the most rigid implant and Neomesh SuperSoft® as the softer, while other two meshes (Neomesh Soft®, Neopore®) remained in between. These two meshes were employed in the experimental study and resulted in similar effect in the abdominal wall cavity and both were close to the healthy case. Simulations confirmed this result while showed potential objections in the case of the other two meshes, due to high values in stresses or elongation that may led to discomfort in real tissue. The use of this methodology on human surgery may provide the surgeons with reliable and useful information to avoid certain meshes on specific-patient treatment.

Chronic pain after mesh versus nonmesh repair of inguinal hernias: A systematic review and a network meta-analysis of randomized controlled trials

BACKGROUND

Chronic pain affects 10%-12% of patients after inguinal hernia repairs. Some have suggested that less foreign material may theoretically prevent pain. If the prevalence of chronic pain is less after nonmesh repairs, selected hernias might be repaired without mesh. Our aim was to clarify if nonmesh repairs are superior to mesh repairs regarding chronic pain.

METHODS

For this systematic review, searches were conducted in five databases. The main outcome was chronic pain reported a minimum of six months after mesh and nonmesh repair in adult patients with a primary inguinal hernia. Only randomized controlled trials (RCTs) were included.

RESULTS

A total of 23 RCTs with 5,444 patients were included. The median follow up was 1.4 years (range 0.5-10). Twenty-one studies reported crude chronic pain rates, and when considering moderate and severe pain, the prevalences of pain after nonmesh repairs and mesh repairs were similar: median 3.5% (0%-16.2%) versus median 2.9% (0%-27.6%), respectively. Both the meta-analyses and the network meta-analysis indicated no difference in chronic pain rates when comparing nonmesh repairs with open- and laparoscopic mesh repairs.

CONCLUSION

Mesh may be used without fear of causing a greater rate of chronic pain.

Cross-Linked Cholecyst-Derived Extracellular Matrix for Abdominal Wall Repair

Abdominal wall repair frequently utilizes either nondegradable or biodegradable meshes, which are found to stimulate undesirable biological tissue responses or which possess suboptimal degradation rate. In this study, a biologic mesh prototype made from carbodiimide cross-linked cholecyst-derived extracellular matrix (EDCxCEM) was compared with small intestinal submucosa (Surgisis^®), cross-linked bovine pericardium (Peri-Guard^®), and polypropylene (Prolene^®) meshes in an in vivo rabbit model. The macroscopic appearance and stereological parameters of the meshes were evaluated. Tailoring the degradation of the EDCxCEM mesh prevents untimely degradation, while allowing cellular infiltration and mesh remodeling to take place in a slower but predictable manner. The results suggest that the cross-linked biodegradable cholecyst-derived biologic mesh results in no seroma formation, low adhesion, and moderate stretching of the mesh. In contrast to Surgisis, Peri-Guard, and Prolene meshes, the EDCxCEM mesh showed a statistically significant increase in the volume fraction (V_v) of collagen (from 34% to 52.1%) in the central fibrous tissue region at both day 28 and 56. The statistically high length density (L_v), of blood vessels for the EDCxCEM mesh at 28 days was reflected also by the higher cellular activity (high V_v of fibroblast and moderate V_v of nuclei) indicating remodeling of this region in the vicinity of a slowly degrading EDCxCEM mesh. The lack of mesh area stretching/shrinkage in the EDCxCEM mesh showed that the remodeled tissue was adequate to prevent hernia formation. The stereo-histological assays suggest that the EDCxCEM delayed degradation profile supports host wound healing processes including collagen formation, cellular infiltration, and angiogenesis. The use of cross-linked CEM for abdominal wall repair is promising.

International guidelines for groin hernia management

INTRODUCTION

Worldwide, more than 20 million patients undergo groin hernia repair annually. The many different approaches, treatment indications and a significant array of techniques for groin hernia repair warrant guidelines to standardize care, minimize complications, and improve results. The main goal of these guidelines is to improve patient outcomes, specifically to decrease recurrence rates and reduce chronic pain, the most frequent problems following groin hernia repair. They have been endorsed by all five continental hernia societies, the International Endo Hernia Society and the European Association for Endoscopic Surgery.

METHODS

An expert group of international surgeons (the HerniaSurge Group) and one anesthesiologist pain expert was formed. The group consisted of members from all continents with specific experience in hernia-related research. Care was taken to include surgeons who perform different types of repair and had preferably performed research on groin hernia surgery. During the Group's first meeting, evidence-based medicine (EBM) training occurred and 166 key questions (KQ) were formulated. EBM rules were followed in complete literature searches (including a complete search by The Dutch Cochrane database) to January 1, 2015 and to July 1, 2015 for level 1 publications. The articles were scored by teams of two or three according to Oxford, SIGN and Grade methodologies. During five 2-day meetings, results were discussed with the working group members leading to 136 statements and 88 recommendations. Recommendations were graded as "strong" (recommendations) or "weak" (suggestions) and by consensus in some cases upgraded. In the Results and summary section below, the term "should" refers to a recommendation. The AGREE II instrument was used to validate the guidelines. An external review was performed by three international experts. They recommended the guidelines with high scores. The risk factors for inguinal hernia (IH) include: family history, previous contra-lateral hernia, male gender, age, abnormal collagen metabolism, prostatectomy, and low body mass index. Peri-operative risk factors for recurrence include poor surgical techniques, low surgical volumes, surgical inexperience and local anesthesia. These should be considered when treating IH patients. IH diagnosis can be confirmed by physical examination alone in the vast majority of patients with appropriate signs and symptoms. Rarely, ultrasound is necessary. Less commonly still, a dynamic MRI or CT scan or herniography may be needed. The EHS classification system is suggested to stratify IH patients for tailored treatment, research and audit. Symptomatic groin hernias should be treated surgically. Asymptomatic or minimally symptomatic male IH patients may be managed with "watchful waiting" since their risk of hernia-related emergencies is low. The majority of these individuals will eventually require surgery; therefore, surgical risks and the watchful waiting strategy should be discussed with patients. Surgical treatment should be tailored to the surgeon's expertise, patient- and hernia-related characteristics and local/national resources. Furthermore, patient health-related, life style and social factors should all influence the shared decision-making process leading up to hernia management. Mesh repair is recommended as first choice, either by an open procedure or a laparo-endoscopic repair technique. One standard repair technique for all groin hernias does not exist. It is recommended that surgeons/surgical services provide both anterior and posterior approach options. Lichtenstein and laparo-endoscopic repair are best evaluated. Many other techniques need further evaluation. Provided that resources and expertise are available, laparo-endoscopic techniques have faster recovery times, lower chronic pain risk and are cost effective. There is discussion concerning laparo-endoscopic management of potential bilateral hernias (occult hernia issue). After patient consent, during TAPP, the contra-lateral side should be inspected. This is not suggested during unilateral TEP repair. After appropriate discussions with patients concerning results tissue repair (first choice is the Shouldice technique) can be offered. Day surgery is recommended for the majority of groin hernia repair provided aftercare is organized. Surgeons should be aware of the intrinsic characteristics of the meshes they use. Use of so-called low-weight mesh may have slight short-term benefits like reduced postoperative pain and shorter convalescence, but are not associated with better longer-term outcomes like recurrence and chronic pain. Mesh selection on weight alone is not recommended. The incidence of erosion seems higher with plug versus flat mesh. It is suggested not to use plug repair techniques. The use of other implants to replace the standard flat mesh in the Lichtenstein technique is currently not recommended. In almost all cases, mesh fixation in TEP is unnecessary. In both TEP and TAPP it is recommended to fix mesh in M3 hernias (large medial) to reduce recurrence risk. Antibiotic prophylaxis in average-risk patients in low-risk environments is not recommended in open surgery. In laparo-endoscopic repair it is never recommended. Local anesthesia in open repair has many advantages, and its use is recommended provided the surgeon is experienced in this technique. General anesthesia is suggested over regional in patients aged 65 and older as it might be associated with fewer complications like myocardial infarction, pneumonia and thromboembolism. Perioperative field blocks and/or subfascial/subcutaneous infiltrations are recommended in all cases of open repair. Patients are recommended to resume normal activities without restrictions as soon as they feel comfortable. Provided expertise is available, it is suggested that women with groin hernias undergo laparo-endoscopic repair in order to decrease the risk of chronic pain and avoid missing a femoral hernia. Watchful waiting is suggested in pregnant women as groin swelling most often consists of self-limited round ligament varicosities. Timely mesh repair by a laparo-endoscopic approach is suggested for femoral hernias provided expertise is available. All complications of groin hernia management are discussed in an extensive chapter on the topic. Overall, the incidence of clinically significant chronic pain is in the 10-12% range, decreasing over time. Debilitating chronic pain affecting normal daily activities or work ranges from 0.5 to 6%. Chronic postoperative inguinal pain (CPIP) is defined as bothersome moderate pain impacting daily activities lasting at least 3 months postoperatively and decreasing over time. CPIP risk factors include: young age, female gender, high preoperative pain, early high postoperative pain, recurrent hernia and open repair. For CPIP the focus should be on nerve recognition in open surgery and, in selected cases, prophylactic pragmatic nerve resection (planned resection is not suggested). It is suggested that CPIP management be performed by multi-disciplinary teams. It is also suggested that CPIP be managed by a combination of pharmacological and interventional measures and, if this is unsuccessful, followed by, in selected cases (triple) neurectomy and (in selected cases) mesh removal. For recurrent hernia after anterior repair, posterior repair is recommended. If recurrence occurs after a posterior repair, an anterior repair is recommended. After a failed anterior and posterior approach, management by a specialist hernia surgeon is recommended. Risk factors for hernia incarceration/strangulation include: female gender, femoral hernia and a history of hospitalization related to groin hernia. It is suggested that treatment of emergencies be tailored according to patient- and hernia-related factors, local expertise and resources. Learning curves vary between different techniques. Probably about 100 supervised laparo-endoscopic repairs are needed to achieve the same results as open mesh surgery like Lichtenstein. It is suggested that case load per surgeon is more important than center volume. It is recommended that minimum requirements be developed to certify individuals as expert hernia surgeon. The same is true for the designation "Hernia Center". From a cost-effectiveness perspective, day-case laparoscopic IH repair with minimal use of disposables is recommended. The development and implementation of national groin hernia registries in every country (or region, in the case of small country populations) is suggested. They should include patient follow-up data and account for local healthcare structures. A dissemination and implementation plan of the guidelines will be developed by global (HerniaSurge), regional (international societies) and local (national chapters) initiatives through internet websites, social media and smartphone apps. An overarching plan to improve access to safe IH surgery in low-resource settings (LRSs) is needed. It is suggested that this plan contains simple guidelines and a sustainability strategy, independent of international aid. It is suggested that in LRSs the focus be on performing high-volume Lichtenstein repair under local anesthesia using low-cost mesh. Three chapters discuss future research, guidelines for general practitioners and guidelines for patients.

CONCLUSIONS

The HerniaSurge Group has developed these extensive and inclusive guidelines for the management of adult groin hernia patients. It is hoped that they will lead to better outcomes for groin hernia patients wherever they live. More knowledge, better training, national audit and specialization in groin hernia management will standardize care for these patients, lead to more effective and efficient healthcare and provide direction for future research.

Comparison of partially-absorbable lightweight mesh with heavyweight mesh for inguinal hernia repair: multicenter randomized study

Purpose

Prosthetic mesh is widely used for inguinal hernia repair; however, pain and stiffness can develop. This study was a prospective, multicenter, single-blind, randomized trial to assess postoperative pain and quality of life according to mesh type after inguinal hernia repair.

Methods

Forty-seven patients who underwent Lichtenstein repair for unilateral inguinal hernia with prosthetic mesh were enrolled and randomly allocated to the partially-absorbable lightweight mesh (LW group, n = 24) or heavyweight mesh group (HW group, n = 23). Data were collected using a visual analogue scale (VAS), Carolinas Comfort Scale (CCS), and Activities Assessment Scale (AAS) at screening and postoperative day 1, 7, 90, and 120; foreign body sensation, sense of stiffness, and sense of pull during activity were also evaluated.

Results

There were no significant differences in patients' demographics and clinical characteristics between groups. The VAS at day 90 was significantly lower in the LW group (0.46 ± 0.78 vs. 0.96 ± 0.82, P = 0.027). The CCS and AAS were significantly lower in the LW group at day 1 (51.33 ± 20.29 vs. 64.65 ± 22.64, P = 0.047 and 39.83 ± 9.88 vs. 46.43 ± 7.82, P = 0.015, respectively). Foreign body sensation was significantly lower in the LW group at day 120 (4.2% vs. 30.4 %, P = 0.023), as was sense of stiffness (P = 0.023). The sense of pull during activity was lower in the LW group at day 90 and 120 (P = 0.012 and P = 0.022, respectively). There was no recurrence or serious complication during follow-up.

Conclusion

Partially-absorbable lightweight prosthetic mesh can be used for inguinal hernia repair safely and improve functional outcomes and quality of life after surgery.

Pain and quality of life after inguinal hernia surgery: a multicenter randomized controlled trial comparing lightweight vs heavyweight mesh (Supermesh Study)

Mesh repair has significantly reduced recurrence rate after groin hernia surgery. Recently, attention has shifted to issues such as chronic pain and discomfort, leading to development of lightweight and partially re-absorbable meshes. The aim of the study was to evaluate the effect of lightweight mesh vs heavyweight mesh on post-operative pain, discomfort and quality of life in short and medium term after inguinal hernia surgery. Eight hundred and eight patients with primary inguinal hernia were allocated to anterior repair (Lichtenstein technique) using a lightweight mesh (Ultrapro^®) or a heavyweight mesh (Prolene^®). Primary outcomes were incidence of chronic pain and discomfort at 6-month follow-up. Secondary endpoints were quality of life (QoL), pain and complication at 1 week, 1 and 6 months. At 6 months, 25% of patients reported pain of some intensity; severe pain was reported by 1% of patients in both groups. A statistically significant difference in favour of lightweight mesh was found at multivariable analysis for pain (1 week and 6 months after surgery: p = 0.02 and p = 0.04, respectively) and QoL at 1 month and 6 months (p = 0.05 and p = 0.02, respectively). There was no difference in complication rate and no hernia recurrences were detected. The use of lightweight mesh in anterior Lichtenstein inguinal hernia repair significantly reduced the incidence of pain and favourably affected the perceived quality of life at 6 months after surgery compared to heavyweight mesh.

Systematic review: laparoscopic treatment of long-standing groin pain in athletes

OBJECTIVES

No single aetiological factor has been proven to cause long-standing groin pain in athletes and no sole operative technique (either open or laparoscopic) has been shown to be the preferred method of repair. The aim of this systematic review was to determine whether there are any differences in the return to full sporting activity following laparoscopic repair of groin pain in athletes.

DATA SOURCES

The minimal access approaches include laparoscopic transabdominal pre-peritoneal (TAPP) or endoscopic total extraperitoneal (TEP) techniques. A systematic literature search was performed in PubMed, SCOPUS, UpToDate and the Cochrane Library databases. Series reporting laparoscopic repair (TAPP/TEP) of groin pain in adult (>18 years) athletes were included. The primary outcome was return to full sporting activity and secondary outcomes included percentage success rates and complications of operations.

RESULTS

Only 18 studies fulfilled the search criteria with both laparoscopic and sports hernia repairs. The studies were mainly observational with some reporting comparative data, but no large randomised controlled trials were detected. The median return to sporting activity of 4 weeks (28 days) was the same for the TAPP as well as TEP techniques. No real difference in secondary outcome measures was shown. More reported cases to date in the literature used the TAPP technique compared with TEP repair (n=605 vs n=266).

CONCLUSIONS

Laparoscopic surgery for elite athlete groin pain is increasingly becoming more common with almost 1000 patients reported since 1997. No particular laparoscopic technique appears to offer any advantage over the other.

Quality-of-life scores in laparoscopic preperitoneal inguinal hernia repair

BACKGROUND

Published support exists for using lightweight polypropylene mesh (PPM) to repair inguinal hernias with increased biocompatibility and decreased foreign body reaction and pain. However, quality of life (QOL) has not been assessed. We assess QOL in patients undergoing laparoscopic totally extraperitoneal hernia repair (TEP) with lightweight PPM.

METHODS

We performed an IRB-approved study of patients undergoing TEP hernia repair. Demographic information and hernia characteristics were collected perioperatively. Baseline Short Form-36 (SF-36), Carolinas Comfort Scale (CCS), and visual analog scale (VAS) for pain were performed preoperatively, and then after 1, 26, and 52 weeks.

RESULTS

Forty-eight patients undergoing TEP with mesh were selected. Average age was 43.2 years (SD = 13.2), and average BMI was 26.1 kg/m(2) (SD = 4.3). Procedures include bilateral hernia, right inguinal hernia, and left inguinal hernia repairs. Mean scores on the CCS(®) and VAS were low during the immediate post-op period and 1 year. SF-36 mean scores for body pain, physical function, and role physical showed decreases at the postoperative survey and then subsequent increases. Pain-associated scores increased during the immediate post-op period. CCS and SF-36 scores demonstrated improvement after 1 year. There was no significant difference in VAS. Bilateral repair patients reported more pain and reduced physical function versus unilateral repairs. Patients with larger mesh reported greater pain scores and reduced physical function scores.

CONCLUSIONS

Laparoscopic inguinal hernia repair is associated with initial declines in QOL in the postoperative period. Improvements appear in the long term. General health does not appear to be impacted by laparoscopic TEP. Smaller mesh and unilateral repairs are associated with improved QOL following laparoscopic TEP with PPM. Multiple metrics for QOL are required to reflect patient recovery.

Biologic mesh versus synthetic mesh in open inguinal hernia repair: system review and meta-analysis

BACKGROUND

Biologic meshes are mostly used for abdominal wall reinforcement in infected fields, but no consensus has been reached on its use for inguinal hernia repairing. The purpose of this study was to compare biologic mesh with synthetic mesh in open inguinal herniorrhaphy.

METHODS

A systematic literature review and meta-analysis was undertaken to identify studies comparing the outcomes of biologic mesh and synthetic mesh in open inguinal hernia repair. Published studies were identified by the databases PubMed, EMBASE and the Cochrane Library.

RESULTS

A total of 382 patients in five randomized controlled trials were reviewed (179 patients in biologic mesh group; 203 patients in synthetic mesh group). The two groups did not significantly differ in chronic groin pain (P = 0.06) or recurrence (P = 0.38). The incidence of seroma trended higher in biologic mesh group (P = 0.03). Operating time was significantly longer with biologic mesh (P = 0.03). There was no significant difference in hematomas (P = 0.23) between the two groups.

CONCLUSIONS

From the data of this study, biologic mesh had no superiority to synthetic mesh in open inguinal hernia repair with similar recurrence rates and incidence of chronic groin pain, but higher rate of seroma and longer operating time. However, this mesh still needs to be assessed in a large, multicentre, well-designed randomized controlled trial.

Standard polypropylene mesh vs lightweight mesh for Lichtenstein repair of primary inguinal hernia: a randomized controlled trial

PURPOSE

The aim of the present clinical study was to compare early and late outcomes after inguinal hernia repair with the heavyweight mesh (HW) and lightweight mesh (LW) during a 3 year follow-up period.

METHODS

226 patients were randomized into LW and HW mesh groups, both of which underwent unilateral primary inguinal hernia repair via the Lichtenstein technique. Wound complications (infection, hematoma, seroma), hernia recurrence, pain and feeling of foreign body in inguinal area were determined in patients. Pain was measured by visual analogue scale.

RESULTS

No statistical difference has been found between LW and HW groups by wound complication (P = 0.80). One case of hernia recurrence has been mentioned in both groups one year after hernioplasty. But there was no detectable difference between the two groups. No significant difference has been found between LW and HW groups by frequency of chronic pain 7 days, 1 and 3 months, 1, 2, and 3 years after surgery. As for the feeling of foreign body in groin it is similar in both groups after 1 and 3 months. Level of feeling of foreign body was significantly lower in LW group 1, 2, and 3 years after surgery, than in HW group (P = 0.03, P = 0.02, P = 0.02, respectively).

CONCLUSION

Our research shows no significant difference in wound complications, hernia recurrence and chronic pain after Lichtenstein hernioplasty, by using of LW and HW meshes. The usage of the LW mesh was associated with less feeling of foreign body than that of the HW mesh, what can be considered as prevalence of LW mesh hernioplasty.

Evaluation of three purely polypropylene meshes of different pore sizes in an onlay position in a New Zealand white rabbit model

BACKGROUND

The aim of the study was to evaluate the influence of the pore size of a polypropylene mesh on the shrinkage and elasticity of the mesh-tissue complex and the inflammatory reaction to the implant in an open onlay hernia repair.

MATERIALS AND METHODS

Twenty-one 10 × 10 cm samples of polypropylene meshes of a different pore size (3.0 × 2.8 mm-PP3, 1.0 × 0.8 mm-PP1 and 0.6 × 0.5 mm-PP.5) were implanted in an onlay position in 21 New Zealand white rabbits. After 90 days of implantation the shrinkage, elasticity and foreign body reaction (FBR) were assessed.

RESULTS

The shrinkage of PP3 was 30.6 ± 4.3 %, PP1 49.3 ± 2.9 % and PP.5 49.5 ± 2.6 %. The shrinkage of PP3 was significantly lower (PP3 × PP1 p = 0.007, PP3 × PP.5 p = 0.005), PP1 and PP.5 were similar. The elasticity was similar. The strength of FBR in mesh pores was similar. The width of foreign body granuloma layers at the mesh-tissue interface was significantly reduced with increasing pore size (inner: PP3 10.1 ± 1.2; PP1 12.5 ± 2.9; PP.5 17.4 ± 5.2 and outer: PP3 21.2 ± 2.5; PP1 30.6 ± 6.3; PP.5 60.4 ± 14.9). All differences between the widths of granuloma layers were statistically significant (p < 0.010). One animal (PP1) was excluded because of a mesh infection.

CONCLUSIONS

Implantation of polypropylene mesh of a pore size of 3 mm in an onlay position is associated with a significant reduction of shrinkage in comparison to a 1 mm pore lightweight and 0.5 mm pore heavyweight mesh. A pore size increase to 3 mm is not sufficient for an improvement of mesh-tissue complex elasticity in comparison to a 1 mm pore lightweight and 0.5 mm heavyweight mesh. Polypropylene mesh with enlarged pores to 3 mm is associated with a similar strength of FBR in mesh pores and a reduced foreign body granuloma in comparison to a 1 mm pore lightweight and 0.5 mm pore heavyweight mesh.

Self-gripping mesh versus sutured mesh in open inguinal hernia repair: system review and meta-analysis

BACKGROUND

The objective of this article was to compare the outcomes of self-gripping mesh (GM) with sutured mesh (SM) in open inguinal hernia repair.

METHODS

A systematic review and meta-analysis were taken to compare the outcomes of GM and SM in open inguinal hernia repair.

RESULTS

A total of 1,353 patients in 6 randomized controlled trials and 2 observational studies were reviewed (666 patients in GM group; 687 patients in SM group). The 2 groups did not significantly differ in chronic groin pain (P = .23) or recurrence (P = .59). The operating time was significantly shorter in GM group (P < .00001). There was no significant difference in infection (P = .18), seromas (P = .35), hematomas (P = .87), or discomfort (P = .58) between the 2 groups.

CONCLUSIONS

The data showed that GM was equivalent to SM in open inguinal hernia repair. However, this new mesh still needs to be confirmed in large, multi-center, well-designed randomized controlled trials.

Laparoscopic versus open inguinal hernia repair

The laparoscopic approach to inguinal hernia surgery is safe and reliable. It has a similar recurrence rate as open tension-free mesh repair. Because the laparoscopic approach has less chronic postoperative pain and numbness, fast return to normal activities, and decreased incidence of wound infection and hematoma, it should be considered an appropriate approach for inguinal hernia surgery. These results can be achieved if a surgeon is proficient in the technique, has a clear understanding of the anatomy, and performs it on a regular basis. This article focuses on questions related to laparoscopic inguinal hernia surgery and provides answers based on published literature.

Comparative study of shrinkage, inflammatory response and fibroplasia in heavyweight and lightweight meshes

PURPOSE

In this manuscript, the authors describe an animal study comparing shrinkage, inflammatory response and fibroplasia in heavyweight (HW-PP) and lightweight polypropylene (LW-PP) meshes.

METHODS

Both meshes were fixed on abdominal fascia of 25 Wistar rats (epifascial onlay placement). They were killed at 7, 28 and 90 days to measure the prostheses. Histological analysis was performed with hematoxylin-eosin for cellular counting and immunohistochemistry to measure collagen types I and III.

RESULTS

The authors found that the LW-PP mesh presented greater median shrinkage than HW-PP mesh at 7 (P = .036), 28 (P = .674) and 90 days (P = .038) postoperatively. There were more neutrophils on LW-PP mesh (P = .008) at 7 days, gradually diminishing in both prostheses. Lymphocytes were similar between the implants at 7 days, diminishing about 50 % on LW-PP mesh (P < .001) at 90 days. Macrophages and giant cells diminished on LW-PP and increased on HW-PP meshes (P < .001). Collagen I/III ratio presented a progressive, almost fivefold rise at 90 days, on both mesh types (P < .001). The collagen I/III ratio was similar between LW-PP and HW-PP meshes at the three times studied.

CONCLUSIONS

It is concluded that LW-PP showed more shrinkage than HW-PP mesh at 7 and 90 days, despite the fact that HW-PP presented more lately foreign body reaction. The collagen I/III ratio was similar between the prostheses and increased during the postimplant period.

Open inguinal hernia repair with the use of polyglycolic acid/trimethylene carbonate absorbable mesh: a critical update of the long-term results

PURPOSE

Our group evaluated on a pilot basis open inguinal hernia repair with the use of a fully absorbable mesh aiming to take mesh inguinal hernia repair one step forward. The purpose of the present study was to assess the long-term results of the proposed technique.

METHODS

Patients that were included in our previous report were followed up at 3 years after the initial operation.

RESULTS

Ten patients underwent open inguinal hernia repair with the use of an absorbable polyglycolic acid/trimethylene carbonate mesh. 3 years after the procedure, from the total of ten patients, two were lost to follow-up (20 %). Three patients (37.5 %), one with direct and two with indirect hernia, were diagnosed clinically with a recurrence at the follow-up of 3 years. Recurrences were developed nearly 2 years--median 24 months (range 18-30)--after the initial operation. Among patients without recurrence none complained about chronic pain, foreign body sensation or numbness. On the other hand, chronic pain was a constant complain in the recurrence patient group.

CONCLUSIONS

The results of the 3-year follow-up in the given patient sample alleviate the initial enthusiasm regarding the use of an absorbable mesh for inguinal hernia repair as an attractive alternative and causes skepticism about the generalized use of the procedure in its certain form.