Weighing the benefits: Exploring the differential effects of light-weight and heavy-weight polypropylene meshes in inguinal hernia repair in a retrospective cohort study

BACKGROUND

Inguinal hernia repair is a common surgical procedure, with more than 20 million cases yearly. Choice between mesh types varies in clinical practice. To compare light-weight polypropylene (LW-PP, 34-36 g/m2) and heavy-weight polypropylene (HW-PP, 95 ​g/m2) meshes.

METHODS

Data from patients who underwent open inguinal hernia repair between 2020 and 2022. Selection criteria ensured homogeneity. Endpoints were to assess the impact of different mesh weights on overall health-related quality of life (HRQoL), using Short Form 36 (SF-36), and to monitor postoperative complications.

RESULTS

Two hundred patients were included in both groups. Lateral and direct hernias occurred in 60.5 ​% and 39.5 ​%. According to EHS, 31.5 ​%, 22.3 ​% and 46.2 ​% were classified as size 1, 2, 3. Follow-up showed similar HRQoL at 30-days, with a favorable trend towards LW-PP mesh offering fewer limitations, better comfort, and improved general health after 12-months. No difference in postoperative paresthesia, wound hematoma, and interference with daily activities.

CONCLUSION

1-year after surgery HRQoL evaluation highlights the non-inferiority of LW-PP. Mesh selection should be tailored, aiming at improving outcomes and postoperative comfort.

Lichtenstein technique for inguinal hernia repair: ten recommendations to optimize surgical outcomes

PURPOSE

Approximately 20 million individuals worldwide undergo inguinal hernia surgery annually. The Lichtenstein technique is the most commonly used surgical procedure in this setting. The objective of this study was to revisit this technique and present ten recommendations based on the best practices.

METHODS

PubMed and Scientific Electronic Library Online were used to systematically search for articles about the Lichtenstein technique and its modifications. Literature regarding this technique and surgical strategies to prevent chronic pain were the basis for formulating ten recommendations for best practices during Lichtenstein surgery.

RESULTS

Ten recommendations were proposed based on best practices in the Lichtenstein technique: neuroanatomical assessment, chronic pain prevention, pragmatic neurectomy, spermatic cord structure management, femoral canal assessment, hernia sac management, mesh characteristics, fixation, recurrence prevention, and surgical convalescence.

CONCLUSION

The ten recommendations are practical ways to achieve a safe and successful procedure. We fell that following these recommendations can improve surgical outcomes using the Lichtenstein technique.

The Lichtenstein technique is being used adequately in inguinal hernia repair: national analysis and review of the surgical technique

INTRODUCTION

it is estimated that approximately 20 million people undergo inguinal hernia surgery annually in the world, with the Lichtenstein technique being the most performed surgical procedure. The objective of this study is to analyze the knowledge of the technical principles used in the Lichtenstein technique.

METHOD

Survey-type intersectional study approved by the research ethics committee of São Camilo University Center (CAAE: 70036523.1.0000.0062). During the research period, 11,622 e-mails were sent to members of the main national surgical societies with research on the technical principles of Lichtenstein surgery. The survey was carried out using an electronic form with 10 multiple-choice questions. The form was answered anonymously on the SurveyMonkey and Google Forms platforms.

RESULT

744 responses were received to the electronic form. Based on this number of respondents, our survey has a confidence level of 95% with a margin of error of 3.5%. It was observed that there is no standardization of the technique among the majority of responders (53.4%). Many surgeons still perform digital dissection of the spermatic cord (47%). A small number of interviewees (15.2%) performed sutures with absorbable thread in the region of the internal oblique aponeurosis, while more than half (55.2%) continued to perform sutures with non-absorbable thread. Most surgeons use a small overlap or fix the mesh juxtaposed to the pubic symphysis (51%).

CONCLUSION

Our research identified that a small percentage of respondents adequately know the technical principles of Lichtenstein surgery. The result brings us new insights into the need to review Lichtenstein technique.

Totally extra-peritoneal repair versus trans-abdominal pre-peritoneal repair for the laparoscopic surgical management of sportsman's hernia: A systematic review and meta-analysis

BACKGROUND

Open and laparoscopic modalities are employed for treatment of sportsman's hernia with totally extra-peritoneal (TEP) and trans-abdominal pre-peritoneal (TAPP) laparoscopic approaches both currently being utilised. At present, neither subtype has demonstrated a beneficial superiority for sportsman's hernia repair, as concluded in the most recent systematic review comparing the outcomes of each technique. The aim of this review was to evaluate current evidence to ascertain whether there was a difference in laparoscopic techniques following sportsman's hernia repair.

METHODS

A systematic literature search was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement standards. Databases searched included PubMed, Scopus and Web of Science to identify all randomised controlled trials (RCTs) and observational studies Risk of bias was assessed using the Cochrane risk of bias tool and Newcastle-Ottawa scale for RCTs and observational studies, respectively.The assessed outcomes included median time to return to sporting activity, complications and the degree of postoperative pain reduction within three months. Random effects model was used to calculate pooled proportion data where feasible. Subgroup analyses were also performed.

RESULTS

28 studies were identified including 2 RCTs and 26 observational studies. No significant differences were observed between techniques in the primary or secondary outcomes. Significant heterogeneity was observed in all outcomes. This was more pronounced for return to sporting activity meaning that meta-analysis was not feasible in this domain. Median time to return to sporting activity was 28 days for both techniques.

CONCLUSIONS

There is no observed difference in the primary and secondary outcomes in either technique. An RCT comparing TEP and TAPP repair is needed to provide definitive data on this matter.

Evaluation of a Novel Absorbable Mesh in a Porcine Model of Abdominal Wall Repair

Bioabsorbable meshes have seen increasing clinical use to reinforce soft tissue, and exist on a spectrum of strength loss versus absorption: several retain their strength for months, but remain in situ for years. Others lose strength fully by 6 weeks. An intermediate profile, with some strength for 3 -4 months, but consistent absorption in less than a year, may be an optimal balance of near-term support and long-term safety. In this large animal study, we evaluate such a mesh (DuraSorb, SIA), assessing its utility in a porcine model of abdominal wall repair.

METHODS

Two full-thickness defects were created in the abdominal walls of nine Yucatan swine via midline approach and repaired preperitoneally with either DuraSorb or long-lasting control mesh (TIGR, Novus Scientific). At 30 days, 3 months, and 1 year, the implantations were assessed by clinical pathology, post-necropsy histopathology, and burst strength testing.

RESULTS

No device-associated complications were found in vivo, at necropsy, or histologically. DuraSorb was well-integrated and vascularized by 30 days. DuraSorb demonstrated minimal/mild inflammation and fibroplasia, and lower inflammatory scores when compared with TIGR at all time points (P < 0.05). Burst strength of the repair sites was higher than adjacent abdominal wall at all time points (P < 0.05).

CONCLUSIONS

DuraSorb provided durable long-term support, minimal inflammation, and consistent absorption in this porcine model of abdominal wall repair, as compared to a long-term control. Clinical data is needed, but these results suggest that this mesh provides adequate structural support while potentially reducing long-term device reactions.

Long-term Comparison of Recurrence Rates Between Different Lightweight and Heavyweight Meshes in Open Anterior Mesh Inguinal Hernia Repair: A Nationwide Population-based Register Study

OBJECTIVE

To compare the reoperation rate for recurrence of different lightweight to heavyweight meshes after an open anterior mesh (OAM) inguinal hernia repair.

SUMMARY BACKGROUND DATA

Lightweight meshes have shown benefits compared with heavyweight meshes in terms of accelerated recovery after surgery with less postoperative pain. The use of such meshes may, however, be associated with an increase in hernia recurrence. Studies of large cohorts with long-term follow-up regarding recurrence are lacking.

METHODS

All OAM groin hernia repairs registered in The Swedish Hernia Register between January 1, 2005 and December 31, 2013 were eligible. Follow-up time was until June 30, 2016. Four groups of meshes were included: polypropylene (PP) heavyweight meshes >50 g/m2 (HWM), regular lightweight PP meshes <50 g/m2 (regular LWM-PP), lightweight PP mesh with absorbable poliglecaprone-25(LWM-PP/PGC), or polyglactin-910(LWM-PP/PG). Primary endpoint was reoperation for recurrence.

RESULTS

76,495 OAM inguinal hernia repairs in male patients were included for statistical analysis. 1676 repairs were reoperated for recurrence. Multivariate analysis demonstrated no significant difference of risk for recurrence between HWM and regular LWM-PP (HR 1.12, P = 0.13). LWM-PP/PGC (HR 1.42, P < 0.001) and LWM-PP/PG (HR 2.05, P < 0.001) resulted in a significant increased risk compared with HWM. Larger hernia defects, direct hernias, and recurrent hernias were associated with an increased risk of reoperation for recurrence.

CONCLUSIONS

Although lightweight meshes with partially absorbable component resulted in an increased risk of recurrence, there was no difference between regular LWM-PP and HWM. Considering that regular LWM-PP has less associated side effects there are no benefits of using HWM in OAM inguinal hernia repair.

Regulatory science for hernia mesh: Current status and future perspectives

Regulatory science for medical devices aims to develop new tools, standards and approaches to assess the safety, effectiveness, quality and performance of medical devices. In the field of biomaterials, hernia mesh is a class of implants that have been successfully translated to clinical applications. With a focus on hernia mesh and its regulatory science system, this paper collected and reviewed information on hernia mesh products and biomaterials in both Chinese and American markets. The current development of regulatory science for hernia mesh, including its regulations, standards, guidance documents and classification, and the scientific evaluation of its safety and effectiveness was first reported. Then the research prospect of regulatory science for hernia mesh was discussed. New methods for the preclinical animal study and new tools for the evaluation of the safety and effectiveness of hernia mesh, such as computational modeling, big data platform and evidence-based research, were assessed. By taking the regulatory science of hernia mesh as a case study, this review provided a research basis for developing a regulatory science system of implantable medical devices, furthering the systematic evaluation of the safety and effectiveness of medical devices for better regulatory decision-making. This was the first article reviewing the regulatory science of hernia mesh and biomaterial-based implants. It also proposed and explained the concepts of evidence-based regulatory science and technical review for the first time.

Lower recurrence rate after groin and primary ventral hernia repair performed by high-volume surgeons: a systematic review

PURPOSE

Hernia repair is a common procedure; however, an overview is lacking regarding the impact of annual surgeon volume and total surgical experience on the outcome of hernia repair. We aimed to explore the impact of annual surgeon volume and total surgical experience on outcomes of groin and primary ventral hernia repair.

METHODS

This systematic review followed the Prefered Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline. A protocol was registered at PROSPERO (CRD42020176140). PubMed, EMBASE, and Cochrane CENTRAL were searched. We investigated recurrence rates after groin and primary ventral hernia repair reported according to annual surgeon volume or total surgical experience with at least 6 months follow-up. Surgeons were pooled in three overlapping categories: high-volume (> 50 cases/year), medium-volume (11-50 cases/year) and low-volume (≤ 25 cases/year).

RESULTS

Ten records for groin hernia and one for primary ventral hernia were included. The median (range) recurrence rates after laparoscopic groin hernia repair for high, medium, and low-volume surgeons were 2.6% (2.3-3.0), 2.4% (0.7-4.6), and 4.2% (1.0-6.8), respectively. The median (range) recurrence rate after open groin hernia repair for high, medium, and low-volume surgeons were 2.1% (2.0-2.2), 1.7% (1.6-2.3), and 2.4% (2.2-5.0). The groin hernia recurrence rate seemed to increase when annual surgeon volume decreased below 25 cases/year. For primary ventral hernia, increased annual surgeon volume was associated with decreased reoperation rate.

CONCLUSION

High-volume surgeons seemed to have lower rates of hernia recurrence after groin as well as primary ventral hernia repair and our data supports the need for centralization of groin hernia repair on individual surgeons.

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.

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.

Pro - inflammatory cytokines and metalloproteinase activation in polypropylene mesh implant in rat subcutaneous tissue

AIMS AND OBJECTIVES

Polypropylene meshes have been increasingly adopted for correction of pelvic organ prolapse due to its lower recurrence rate when compared to surgeries without meshes. The study of the interaction of these materials with the host tissue may contribute to the development of materials with best biocompatibility and, consequently, less complication rates.

MATERIALS AND METHODS

The present study compares the inflammatory reaction of standard-weight (SW) and lightweight (LW) meshes (72 g/m216g/m2 respectively), implanted in the abdomen of 20 adult rats, which were euthanized in four or 30 days. Quantification of pro-inflammatory markers, IL-1 and TNF-α, and of metalloproteinases, MMP2 and MMP3, were carried out through immunohistochemistry with AxioVision ® software.

RESULTS

There were no significant differences in the quantification of IL-1 and TNF-α in LW versus SW meshes. However, IL-1 quantification increased along time (30 days >4 days, p=0.0269). Also, MMP-2 quantification was similar to SW and LW and both presented a significant increase along time (30 days >4 days, p < 0.0001). MMP-3 quantification also showed no difference between the SW and LW groups, but increased along time (30 days >4 days, p=0.02).

CONCLUSIONS

Mesh's density did not influence the quantification of pro-inflammatory cytokines IL-1 and TNF-α and metalloproteinases 2 and 3. The increased expression of IL-1, MMP-2 and MMP-3 over time could represent a longstanding inflammatory response after PP mesh implantation. Possibly, the occurrence of adverse events following PP prosthetic implants can be influenced by other factors, not solely related to the amount of implanted material.

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.

Desarda versus Lichtenstein technique for the treatment of primary inguinal hernia: A systematic review

BACKGROUND

The aim of this study was to compare the effectiveness between Desarda and Lichtenstein inguinal hernia repair.

METHODS

An electronic search for articles about Desarda and Lichtenstein technique published between 2001 and July 2017 was conducted in PubMed, Cochrane Library, Web of Science and EMBASE database. Meta-analysis was performed on surgical time, postoperative recovery, complications and recurrence rate.

RESULTS

Eight primary studies identified a total of 1014 patients, of whom 500 and 514 underwent Desarda herniorrhaphy and Lichtenstein herniorrhaphy, respectively. There was no significant difference in terms of operating time, return to normal gait, pain score, wound infection, hematoma, foreinbody sensation, seroma and recurrence rate.

CONCLUSIONS

Current evidence suggests that there is no difference between Desarda and Lichtenstein technique in short-term effectiveness. Further high-quality, long follow-up randomized controlled trials are needed to provide more reliable evidence.

Randomized Clinical Trial Comparing Low Density versus High Density Meshes in Patients with Bilateral Inguinal Hernia

We present a randomized clinical trial to compare postoperative pain, complications, feeling of a foreign body, and recurrence between heavyweight and lightweight meshes in patients with bilateral groin hernia. Sixty-seven patients with bilateral hernia were included in our study. In each patient, the side of the lightweight mesh was decided by random numbers table. Pain score was measured by visual analogue scale, on 1st, 3rd, 5th, and 7th postoperative day, and one year after the surgery. There were no statistically significative differences between both meshes in postoperative complications. About differences of pain average, there were statistically significant differences only on the 1st postoperative day (P <0.01) and the 7th postoperative day (P <0.05). In the review after a year, there were no statistically significative differences in any parameter. In our study, we did not find statistically significative differences between lightweight and heavyweight meshes in postoperative pain, complications, feeling of a foreign body, and recurrence, except pain on 1st and 7th postoperative day.

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.

Surgical risk factors for recurrence in inguinal hernia repair - a review of the literature

Despite all the progress made in inguinal hernia surgery driven by the development of meshes and laparoendoscopic operative techniques, the proportion of recurrent inguinal hernias is still from 12% to 13%. Recurrences can present very soon after primary inguinal hernia repair generally because of technical failure. However, they can also develop much later after the primary operation probably due to patient-specific factors. Supported by evidence-based data, this review presents the surgical risk factors for recurrent inguinal hernia after the primary operation. The following factors are implicated here: choice of operative technique and mesh, mesh fixation technique, mesh size, management of medial and lateral hernia sac, sliding hernia, lipoma in the inguinal canal, operating time, type of anesthesia, participation in a register database, femoral hernia, postoperative complications, as well as the center and surgeon volume. If these surgical risk factors are taken into account when performing primary inguinal hernia repair, a good outcome can be expected for the patient. Therefore, they should definitely be observed.

Absorbable Meshes in Inguinal Hernia Surgery: A Systematic Review and Meta-Analysis

PURPOSE

Absorbable meshes used in inguinal hernia repair are believed to result in less chronic pain than permanent meshes, but concerns remain whether absorbable meshes result in an increased risk of recurrence. The aim of this study was to present an overview of the advantages and limitations of fully absorbable meshes for the repair of inguinal hernias, focusing mainly on postoperative pain and recurrence.

METHODS

This systematic review with meta-analyses is based on searches in PubMed, Embase, Cochrane, and Psychinfo. Included study designs were case series, cohort studies, randomized controlled trials (RCTs), and non-RCTs. Studies had to include adult patients undergoing an inguinal hernia repair with a fully absorbable mesh.

RESULTS

The meta-analyses showed no difference in recurrence rates (median 18 months follow-up) and chronic pain rates (1 year follow-up) between absorbable- and permanent meshes. Crude chronic pain rates for the RCTs were 2.1% for the absorbable meshes and 7.6% for the permanent meshes. For the absorbable meshes, medial hernias were more susceptible for recurrence compared with lateral hernias ( P < .0005). None of the studies reported allergic reactions or other serious adverse events related to the absorbable mesh.

CONCLUSIONS

Patients with an absorbable mesh seem to have less chronic pain following inguinal hernia surgery compared with permanent meshes, without increased risk of recurrence.

Formation of adhesion after intraperitoneal application of TiMesh: experimental study on a rodent model

BACKGROUND

After laparoscopic repair of an incisive hernia, intraperitoneal prosthetic mesh, as a foreign material, is a strong stimulus for the development of adhesion, which may be the cause of serious complications. This experimental study compared three different meshes and their ability to prevent the formation of adhesion and shrinkage.

METHODS

Ninety rats were divided randomly into three groups: in Group 1 Proceed mesh was implanted, in Group 2 Ultrapro mesh was implanted, and in Group 3 TiMesh was implanted. Mesh samples were fixed as an intraabdominal mesh in the upper part of the abdomen. Ten animals from each group were sacrificed on days 7, 28 and 60 post-surgery. After opening the abdomen, the formation of adhesion was assessed according to the Surgical Membrane Study Group (SMSG) score, the percentage of shrinkage of the mesh was established and inflammatory reaction scored.

RESULTS

The SMSG score for adhesion was statistically significantly higher on all the postoperative days in the Proceed and Ultrapro mesh groups than in the TiMesh group which caused milder inflammatory reaction on 60th day than others meshes. The size of the mesh after 7 days was statistically significantly smaller in the Proceed and Ultrapro groups than in the TiMesh group, but after 60 days it was statistically significantly larger than in the TiMesh group.

CONCLUSION

The least formation of adhesion was noted in the TiMesh group, in which the highest level of shrinkage was noticed after 28 and 60 days. TiMesh has advantages over the other meshes studied, but a larger size mesh may be recommended for intraperitoneal application.

Pectus excavatum repair using Prolene polypropylene mesh

OBJECTIVE

We aimed to assess the clinical outcomes of our surgical technique for repair of pectus excavatum using Prolene polypropylene mesh.

METHODS

Among 29 patients with pectus excavatum, the major complaint was cosmetic dissatisfaction, and the main symptom was exercise dyspnea in 15 patients. The Haller index used to assess pectus excavatum severity; it was significant in 22 patients. In all patients, a 2-layer sheet of Prolene polypropylene mesh was placed behind the sternum.

RESULTS

No serious complication was observed postoperatively, and all patients were satisfied with the cosmetic result. Mitral valve prolapse improved in all cases after 3 months. Spirometry revealed improved pulmonary function after surgery.

CONCLUSION

With due attention to the advantages of Prolene polypropylene mesh, such as remaining permanently in place, adapting to various stresses encountered in the body, resisting degradation by tissue enzymes, and trimming without unraveling, we concluded that this mesh is suitable for use as posterior sternal support in pectus excavatum patients.

MRI is unable to illustrate the absorption time of the absorbable TIGR mesh in humans: a case report

A male patient had a bilateral laparoscopic inguinal hernia repair in 2012. The right-sided hernia was treated with a permanent mesh, and the left-sided hernia received an absorbable mesh. The absorbable TIGR mesh has been proved to be completely absorbed and replaced by new connective tissue after 3 years in sheep. The patient was therefore followed for 3 years by annual magnetic resonance imagings (MRIs) to illustrate the absorption time in humans. During follow-up, the thickness of the absorbable mesh slightly decreased, and at the last clinical examination, the patient was without a recurrence. However, MRI failed to illustrate absorption of the TIGR mesh, perhaps since new connective tissue and the mesh material had the same appearance on the images. In conclusion, MRI was unable to confirm an absorption time of 3 years for the TIGR mesh, and further studies are needed to investigate if the mesh also completely absorbs in humans.

Patient-Related Risk Factors for Recurrence After Inguinal Hernia Repair

Background. Several factors influence the risk of recurrence after inguinal hernia surgery; however, a systematic review and meta-analysis of patient-related risk factors for recurrence after inguinal hernia surgery has not been performed earlier. Methods. MEDLINE, Embase, and Cochrane databases were searched in June 2013 for studies evaluating patient-related risk factors for recurrence after inguinal hernia operation. Observational studies evaluating nontechnical patient-related risk factors for recurrence after inguinal hernia surgery were included. Outcome variables were grouped under patient demographics, hernia characteristics, connective tissue composition and degradation, habits and social relations, and conditions related to inguinal hernia recurrence. Results. From a total of 5061 records screened, we included 40 observational studies enrolling 720 651 inguinal hernia procedures in 714 917 patients in the systematic review. Of the 40 studies, 14 studies were included in 8 meta-analyses evaluating sex, hernia type, hernia size, re-recurrence, bilaterality, mode of admission, age, and smoking as risk factors for recurrence after inguinal hernia surgery in a total of 378 824 procedures in 375 620 patients. Conclusions. We found that female sex, direct inguinal hernias at the primary procedure, operation for a recurrent inguinal hernia, and smoking were significant risk factors for recurrence after inguinal hernia surgery. This knowledge of patient-related risk factors for recurrence after inguinal hernia surgery could be implemented in clinical practice.

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.