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

Inguinal hernia: Lichtenstein VS Shouldice technique repair: A randomized controlled trial

Background

Inguinal hernia repair is the most frequent operation in general surgery. The chance of a person having to undergo an inguinal hernia operation during his/her life is quite high, 27 % in men and 3 % in women. European Hernia Society guidelines state that the Lichtenstein technique (mesh-based repair) is the standard treatment of elective inguinal hernia in adults. Some authors consider the Shouldice technique (tissue-based repair) the best conventional method for open hernia repair. In this study, we compared these two methods.

Methods

In This randomized study, 452 patients were randomly allocated into 2 groups. 51 patients were lost during follow-up period and were excluded from further analysis in the study. Finally, the analyzed patients were 183 patients in Shouldice technique group and 218 patients in Lichtenstein technique group. All patients were examined after 1 week, 1, 3 months, 1, 2, and 3 years after the operation date.

Results

After 3 years follow up Recurrence of hernia in Shouldice technique group was 7.1 % and in Lichtenstein technique group was 3 % with significant differences (p-value 0.006). No statistically significant differences were found between the groups in wound infection, Seroma, hematoma, Hydrocele, Bladder damage, chronic pain in the inguinal region, and Patient Satisfaction level after surgery.

Conclusion

It seems that inguinal hernia treatment by the Lichtenstein technique is better than the Shouldice technique in elective patients.

Definition of Mesh Weight and Pore Size in Groin Hernia Repair: A Systematic Scoping Review of Randomised Controlled Trials

Introduction: Groin hernia literature often uses the terms light- and heavyweight and small or large pores to describe meshes. There is no universal definition of these terms, and the aim of this scoping review was to assess how mesh weight and pore sizes are defined in the groin hernia literature. Methods: In this systematic scoping review, we searched PubMed, Embase, and Cochrane CENTRAL. We included randomised controlled trials with adults undergoing groin hernia repair with the Lichtenstein or laparoscopic techniques using a flat permanent polypropylene or polyester mesh. Studies had to use the terms lightweight, mediumweight, or heavyweight to be included, and the outcome was to report how researchers defined these terms as well as pore sizes. Results: We included 48 studies with unique populations. The weight of lightweight meshes ranged from 28 to 60 g/m2 with a median of 39 g/m2, and the pore size ranged from 1.0 to 4.0 mm with a median of 1.6 mm. The weight of heavyweight meshes ranged from 72 to 116 g/m2 with a median of 88 g/m2, and the pore size ranged from 0.08 to 1.8 mm with a median of 1.0 mm. Only one mediumweight mesh was used weighing 55 g/m2 with a pore size of 0.75 mm. Conclusion: There seems to be a consensus that meshes weighing less than 60 g/m2 are defined as lightweight and meshes weighing more than 70 g/m2 are defined as heavyweight. The weight terms were used independently of pore sizes, which slightly overlapped between lightweight and heavyweight meshes.

Cytomorphological Effects of Lightweight and Heavyweight Polypropylene Mesh on the Ilioinguinal Nerve: An Experimental Study

Objective This study aimed to investigate the cytomorphological effects of heavyweight and lightweight mesh on the ilioinguinal nerve in an experimental animal model. Methods Sixteen New Zealand male rabbits were included in the study. The left inguinal regions of the first six animals were assigned as controls and the right inguinal regions were assigned as the sham group. The left inguinal regions of the remaining 10 animals were assigned as the lightweight mesh group and the right inguinal regions were assigned as the heavyweight mesh group. No intervention was performed in the control group. In the sham group, only ilioinguinal nerve exploration was performed. In mesh groups, ilioinguinal nerve exploration was performed and the mesh was implanted on the ilioinguinal nerve. After three months, ilioinguinal nerve specimens were excised from both sides for cytomorphological examination. Results Myelin sheath thickening, separation of the myelin layers, and myelin vacuolization were more pronounced in the heavyweight mesh group compared to the lightweight mesh group. The G-ratio was moderately increased in the heavyweight mesh group when compared to other groups. The ratio of fibers with ≤4 µm diameter was higher in the lightweight mesh group compared to other groups, and the ratio of fibers with ≥9 µm diameter was higher in the heavyweight mesh group than in the other groups (p<0.05). Conclusion Both of the meshes induce cytomorphological alterations on the adjacent nerve tissues caused by foreign body reaction and compression. Ilioinguinal nerve degeneration was more pronounced in the heavyweight mesh than in the lightweight mesh. Histological alterations on the ilioinguinal nerves caused by different meshes may be related to chronic pain after hernia surgery. We believe our study will serve as a guide for future studies on the topic.

Chronic pain after open inguinal hernia repair: expertise-based randomized clinical trial of heavyweight or lightweight mesh

BACKGROUND

There is a shortage of high-quality studies regarding choice of mesh in open anterior inguinal hernia repair in relation to long-term chronic pain. The authors hypothesized that heavyweight compared with lightweight mesh causes increased postoperative pain.

METHODS

An RCT was undertaken between 2007 and 2009 at two sites in Sweden. Men aged 25 years or older with an inguinal hernia evaluated in the outpatient clinic were randomized in an unblinded fashion to heavyweight or lightweight mesh for open anterior inguinal hernia repair. Data on pain affecting daily activities, as measured by the Short-Form Inguinal Pain Questionnaire 9-12 years after surgery, were collected as the primary outcome. Differences between groups were evaluated by generalized odds and numbers needed to treat.

RESULTS

A total of 412 patients were randomized; 363 were analysed with 320 questionnaires sent out. A total of 271 questionnaires (84.7 per cent) were returned; of these, 121 and 150 patients were in the heavyweight and lightweight mesh groups respectively. Pain affecting daily activities was more pronounced in patients randomized to heavyweight versus lightweight mesh (generalized odds 1.33, 95 per cent c.i. 1.10 to 1.61). This translated into a number needed to treat of 7.06 (95 per cent c.i. 4.28 to 21.44). Two reoperations for recurrence were noted in the heavyweight mesh group, and one in the lightweight mesh group.

CONCLUSION

A large-pore lightweight mesh causes significantly less pain affecting daily activities a decade after open anterior inguinal hernia repair. Registration number: NCT00451893 (http://www.clinicaltrials.gov).

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.

Significance of umbilical trocar size and intra-abdominal pressure on postoperative pain after transabdominal preperitoneal repair for inguinal hernia

INTRODUCTION

Laparoscopic inguinal hernia repair is reported to be associated with lower postoperative pain than open repair. However, in the actual clinical setting, some patients experience relatively severe pain. This study aimed to elucidate surgical factors that affect pain after transabdominal preperitoneal (TAPP) repair.

METHODS

We evaluated 199 patients who underwent elective TAPP for inguinal hernia from 2014 to 2019 in Heisei Memorial Hospital. The umbilical trocar size was changed from 12 to 5 mm from October 2017. The pneumoperitoneum intra-abdominal pressure was changed from 10 to 8 mmHg from 2019. Postoperative pain scores and analgesics were compared between patients who were grouped according to trocar size and intra-abdominal pressure, as well as 80 patients who received open repair.

RESULTS

Patients with a 12 mm trocar had significantly higher pain than open repair patients (P < .0001). Patients with a 5 mm umbilical trocar and 8 mm Hg intra-abdominal pressure had significantly lower pain than a 12 mm trocar (P = .025) and did not significantly differ with pain after open repair. Analgesic use significantly decreased in patients using a 5 mm trocar than 12 mm (P = .002).

CONCLUSION

Umbilical trocar size and pneumoperitoneum intra-abdominal pressure were significantly associated with post-TAPP pain. Using a 5 mm umbilical trocar and 8 mm Hg intra-abdominal pressure achieved pain levels as comparatively low as open repair.

Long-term outcomes after Lichtenstein repair using titanium-coated mesh: A retrospective cohort study

OBJECTIVE

To examine the long-term outcomes such as recurrence, foreign body feeling and chronic pain of titanium-coated mesh (TCM) versus standard polypropylene mesh (PM) after Lichtenstein repair (LR).

METHODS

In this retrospective cohort study, patients who underwent TCM and PM in LR were evaluated between May 2014 and January 2018 at Ordu University Training and Research Hospital in Turkey. Primary outcomes (age, gender, body mass index, smoking habits, comorbid diseases, American Society of Anesthesiologists score, hernia type, side of hernia, duration of hernia presentation and operative time) and secondary outcomes (surgical site occurence, recurrence, foreign body feeling and chronic pain) were analyzed. Patients were divided into two groups according to the mesh elected (TCM and PM); titanium group (TG) and polypropylene group (PG), respectively.

RESULTS

In this study, 221 patients were analyzed; TCM was used in 72 (32.6%) patients and PM was used in 149 (67.4%) patients. No difference was found between groups in terms of primary outcomes (p>0.05). In the analysis of secondary outcomes, surgical site occurence was similar in both groups (p>0.05). Recurrence was observed in 1.39% (n=1) of TG and 2.01% (n=3) of PG. No difference was found between groups in terms of recurrence (p=0.606). Foreign body feeling was observed in 15.3% (n=11) of TG and 27.5% (n=41) of PG. Chronic pain was observed in 4.2% (n=3) of TG and 12.8% (n=9) of PG. Significant differences were found between groups in terms of chronic pain and foreign body feeling (p=0.046 and p=0.044, respectively).

CONCLUSION

The result of this study shows that in LR, TCM leads to less foreign body feeling and chronic pain than PM. However, there was no difference in terms of recurrence between these meshes.

A new semiresorbable mesh for primary inguinal repair: a preliminary observational study on quality of life and safety

BACKGROUND

A currently unsolved problem of open inguinal hernia repair (IHR) is chronic postoperative inguinal pain (CPIP), which affects 10-12% of patients after IHR. In the present paper, we explored the results of a newly designed partially absorbable mesh made of polypropylene and polylactic acid (HybridMesh^®) for open hernia repair and its impact on postoperative safety, efficacy, comfort and pain.

METHODS

A prospective multicentric pilot trial was conducted in third-referral centers across Italy (n = 5). Inclusion criteria were unilateral primary inguinal hernia in patients of both genders and BMI < 30 kg/m². All patients were submitted to elective Lichtenstein mesh hernia repair under local anesthesia with HybridMesh. Primary outcome measure was the evaluation of Carolina Comfort Scale and modifications at 2 years after surgery and its correlation with surgical variables; secondary outcomes were postoperative early and late morbidity, recurrence and postoperative early quality of life.

RESULTS

Between 2015 and 2016, 125 (5 female) patients were operated, 2-year follow-up rate was 100%. The surgical site occurrence rate was 28% without the need of procedural interventions. Twenty-four months after surgery, no case of severe CPIP was recorded and altered global CCS score was present in 16 patients (13.0%). At univariate analysis, CCS score was negatively affected by fixation with sutures (OR 3.949; 95% CI 1.334-13.300), with no effect shown on multivariate analysis. Alterations in pain and movement limitations domains of CCS were observed in 9.7% of patients, at univariate analysis; they occurred more frequently when the mesh was sutured (OR 4.437; 95% CI 1.387-17.025) and in patients suffering from SSO (ecchymosis: OR 3.269; 95% CI 1.032-10.405); however, no effect was shown on multivariate analysis. Two recurrences (1.6%) were identified within the first postoperative year.

CONCLUSIONS

The results of this study support the safety, efficacy and good tolerability of HybridMesh as a device to treat primary unilateral inguinal hernia during open anterior approach. Further studies are needed to clarify its role in comparison to currently available devices at longer follow-ups.

Lightweight mesh is recommended in open inguinal (Lichtenstein) hernia repair: A systematic review and meta-analysis

BACKGROUND

The use of lightweight mesh for inguinal hernia repair has been suggested to be preferable compared with heavyweight mesh. Nevertheless, surgeons do not use lightweight mesh routinely, possibly owing to the higher price and lack of confidence in evaluation of previous evidence. The aim of this systematic review and meta-analysis is to update the available randomized controlled trials and provide a recommendation on the use of lightweight mesh or heavyweight mesh in open inguinal hernia repair.

METHODS

A literature search was conducted in May 2019 in MEDLINE, Embase and the Cochrane library for randomized controlled trials comparing lightweight (≤50 g/m²) and heavyweight (>70 g/m²) mesh in patients undergoing open (Lichtenstein) surgery for uncomplicated inguinal hernias. Outcomes were recurrences (overall, after direct or indirect repair), chronic pain (analyzing any and severe pain), and the feeling of a foreign body. The level of evidence was assessed using GRADE. Risk ratios and 95% confidence intervals were calculated by random effect meta-analyses.

RESULTS

Twenty-one randomized controlled trials involving 4,576 patients (lightweight mesh 2,257 vs heavyweight mesh 2,319) were included. Follow-up ranged from 3 to 60 months. No difference between lightweight mesh and heavyweight mesh was determined for recurrence rates (lightweight mesh 42 of 2,068 and heavyweight mesh 34 of 2,132; risk ratios 1.22; 95% confidence interval, 0.76-1.96) or severe pain (lightweight mesh 14 of 1,517 and heavyweight mesh 26 of 1,591; risk ratios 0.73; 95% confidence interval, 0.38-1.41). A significant reduction was seen for any pain after lightweight mesh (234 of 1,603) compared with heavyweight mesh (322 of 1,683; risk ratios 0.78; 95% confidence interval, 0.64-0.96) and for the feeling of a foreign body (lightweight mesh 130 of 1,053 and heavyweight mesh 209 of 1,035; risk ratios 0.64; 95% confidence interval, 0.51-0.80).

CONCLUSION

Lightweight mesh should be used in open (Lichtenstein) inguinal hernia repair.

Meta-Analysis of Randomized Controlled Trials Comparing Lightweight and Heavyweight Mesh for Laparoscopic Total Extraperitoneal Inguinal Hernia Repair

The aim of this study was to compare the outcomes of lightweight and heavyweight mesh on postoperative recovery in laparoscopic total extraperitoneal (TEP) inguinal hernia repair. PubMed, Embase, Science Citation Index, and the Cochrane Library were used to search for published clinical randomized controlled trials, which compared lightweight meshes with heavyweight meshes in TEP inguinal hernia repair. The outcomes were calculated as risk ratios with 95 per cent confidence intervals using RevMan 5.2. Eight randomized controlled trials were included. Compared with a heavyweight mesh, the lightweight mesh led to a higher incidence of recurrence (risk ratio = 2.52, 95% confidence interval 1.10–5.81; P = 0.03). There was no significant difference in chronic moderate to severe pain, foreign body sensation, and seroma. The use of lightweight mesh is not recommended for TEP inguinal hernia repair.

Long-term assessment of surgical and quality-of-life outcomes between lightweight and standard (heavyweight) three-dimensional contoured mesh in laparoscopic inguinal hernia repair

BACKGROUND

Mesh weight is a possible contributor to quality-of-life outcomes after inguinal hernia repair. This study compares lightweight mesh versus heavyweight mesh in laparoscopic inguinal hernia repair.

METHODS

A prospective, single-center, hernia-specific database was queried for all adult laparoscopic inguinal hernia repair with three-dimensional contoured mesh (3-D Max, Bard, Inc, New Providence, NJ) from 1999 to June 2016. Demographics and outcomes were analyzed. Quality of life was evaluated preoperatively and after 2 weeks, 4 weeks, 6 months, 12 months, and 24 months, using the Carolinas Comfort Scale. Univariate analysis and multivariate logistic regression were performed.

RESULTS

A total of 1,424 laparoscopic inguinal hernia repair were performed with three-dimensional contoured mesh, with 804 patients receiving lightweight mesh and 620 receiving heavyweight mesh. Patients receiving lightweight mesh were somewhat younger (52.6 ± 14.8 years vs 56.3 ± 13.7 years, P < .0001), with slightly lower body mass indices (26.4 ± 9.9 vs 27.1 ± 4.3, P < .0001). Lightweight mesh was used less often in incarcerated hernias (12.5% vs 16.8%, P = .02). There were a total of 3 surgical site infections. There were no differences in complications between groups except for seroma. Although on univariate analysis, seromas appeared to occur more frequently with heavyweight mesh (21.5% vs 7.9%). On multivariate analysis, heavyweight mesh was not independently associated with seroma formation. Average follow-up was 20 months. Recurrence rates were similar between lightweight mesh and heavyweight mesh (0.7 vs 0.6% P > .05). At all points of follow-up (4 week to 3 years), quality-of-life outcomes of discomfort, mesh sensation, and movement limitation scores were similar between lightweight mesh and heavyweight mesh.

CONCLUSION

Contoured lightweight mesh and heavyweight mesh in laparoscopic inguinal hernia repair yield excellent recurrence rates and no difference in postoperative complications or quality of life. Considering the lack of outcome difference with long-term follow-up, heavyweight mesh may be considered for use in laparoscopic inguinal hernia repair patients.

Chronic pain, discomfort, quality of life and impact on sex life after open inguinal hernia mesh repair: an expertise-based randomized clinical trial comparing lightweight and heavyweight mesh

Purpose

There is a paucity of high-quality evidence concerning mesh choice in open inguinal hernia repair. Using an expertise-based randomized clinical trial design, we aimed to evaluate the postoperative impact of two different mesh types on pain and discomfort, quality of life and sex life.

Methods

In two regional hospitals, male patients with primary inguinal hernia were randomized to one of two groups of surgeons that performed the Lichtenstein operation. One group of surgeons used a heavyweight polypropylene mesh (90 g/m², Bard™ Flatmesh, Davol) while the second group employed a lightweight mesh (28 g/m², ULTRAPRO™, Ethicon). Follow-up data were collected by questionnaires and outpatient visits in the range of 1–3 years after surgery.

Results

Some 412 patients were randomized and 363 patients were analysed. There was no difference in pain between groups after surgery but a statistically significant difference concerning awareness of a groin lump and groin discomfort, favouring the lightweight group 1 year after surgery. No differences in quality of life between groups could be detected but both groups had a substantially better quality of life postoperatively, as compared to before surgery. In the analysis of impact on sex life, no differences between mesh groups were found.

Conclusion

The Lichtenstein operation performed for primary inguinal hernia improves quality of life for most of the male patients, independently of the type of mesh used. The lightweight mesh group experienced less awareness of a groin lump and groin discomfort 1 year postoperatively.

ClinicalTrials.gov Identifier: NCT00451893.

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.

Risk factors of chronic pain after inguinal hernia repair: a systematic review

Introduction

Chronic postoperative inguinal pain (CPIP) is the most common complication after inguinal hernia operation. Eighteen percent (range, 0.7%-75%) of patients suffered from CPIP after open inguinal hernia repair and 6% (range, 1%-16%) reported CPIP after laparoendoscopic groin hernia repair. The incidence of clinically significant CPIP with impact on daily activities ranged between 10% and 12%. Debilitating CPIP with severe impact on normal daily activities or work was reported in 0.5%-6% of the cases.

Materials and methods

PubMed, Medline, Embase, and the Cochrane Database were searched for studies on risk factors for chronic pain after open and endoscopic hernia repair. A systematic review of the literature was conducted using the grading of recommendations, assessment, development, and evaluations (GRADE) methodology.

Results

Risk factors for CPIP with strong evidence include female gender, young age, high intensity of preoperative pain, high early postoperative pain intensity, history of chronic pain other than CPIP, operation for a recurrent hernia, and open repair technique. Risk factors for CPIP with moderate evidence include postoperative complications, neurolysis, and preservation of the ilioinguinal nerve in Lichtenstein repair. Risk factors for CPIP with low evidence include genetic predisposition (DQB1*03:02 HLA haplotype), lower preoperative optimism, high pain intensity to tonic heat stimulation, inadequate suture/staple/clip mesh fixation, ignorance of the inguinal nerves, less experienced surgeon, sensory dysfunction in the groin, and worker's compensation.

Conclusion

Detailed knowledge of the risk factors, meticulous operative technique with profound knowledge of the anatomy, proper nerve identification and handling, optimization of prosthetic materials, and careful fixation are of utmost importance for the prevention of CPIP.