Contemporary Abdominal Wall Reconstruction: Emerging Techniques and Trends

Abdominal wall reconstruction is a common and necessary surgery, two factors that drive innovation. This review article examines recent developments in ventral hernia repair including primary fascial closure, mesh selection between biologic, permanent synthetic, and biosynthetic meshes, component separation, and functional abdominal wall reconstruction from a plastic surgery perspective, exploring the full range of hernia repair's own reconstructive ladder. New materials and techniques are examined to explore the ever-increasing options available to surgeons who work within the sphere of ventral hernia repair and provide updates for evolving trends in the field.

Large Penetrating Wounds to the Chest Managed With Immediate Chest Wall Reconstruction Using Biologic Mesh, Titanium Plates, and Rotational Tissue Flaps

Large open chest wall wounds can be difficult to manage due to full-thickness tissue loss with underlying rib fractures and exposed lung parenchyma. Historically, the use of synthetic material has been discouraged in the traumatic setting with the concern that it may be associated with an increased risk of infection. We present 4 patients with large open injuries to the thorax-one from blunt and three from penetrating trauma. We describe our initial management followed by prompt surgical repair using biologic mesh, titanium rib spanning plates, and rotational tissue flaps with Z-plasty of the skin for definite closure. All patients did well post-operatively without complications or wound infections. With the appropriate management, we suspect there may be an advantage in performing immediate reconstruction and closure in large open thoracic injuries utilizing biologic mesh and titanium rib spanning plates with a lower risk of infection than previously believed.

Formation of Biologic Plug and Patch Mesh for Use in Perforated Femoral Hernia

Incarcerated inguinal hernias with contamination frequently lead to an open inguinal hernia primary repair. If no contamination is present, a tension-free repair with mesh is a good option. In this case, we encountered an incarcerated femoral hernia with perforation of the small bowel. We will describe and demonstrate via video how to incorporate a tension-free repair with mesh in a contaminated field with formation of a plug and patch made from biologic mesh.

Biologic Versus Synthetic Mesh in Ventral Hernia Repair: Participant-Level Analysis of Two Randomized Controlled Trials at Twenty-Four to Thirty-Six Months

Background: Biologic mesh has been used increasingly in complex ventral hernia repair despite limited evidence at low risk of bias supporting its use. Patients and Methods: We performed a participant-level analysis of published randomized controlled trials (RCTs) comparing biologic to synthetic mesh with complex ventral hernia repair at 24 to 36 months. Primary outcome was major complication (composite of mesh infection, recurrence, reoperation, or death) at 24 to 36 months post-operative. Secondary outcomes included length of index hospital stay, surgical site occurrence, surgical site infection, and death. Outcomes were assessed using both frequentist and Bayesian generalized linear regression models. Results: A total of 252 patients from two RCTs were included, 126 patients randomized to the intervention arm of biologic and 126 patients to the control of synthetic mesh with median follow-up of 29 (23, 38) months. Major complication occurred in 33 (33%) patients randomized to biologic, and 39 (38%) patients randomized to synthetic mesh, (relative risk [RR] 0.91, 95% confidence interval [CI] 0.63-1.31; p value = 0.600). Bayesian analysis demonstrated that compared with synthetic mesh, biologic mesh had similar probability of major complications at 24 to 36 months post-operative. The remainder of outcomes demonstrated slight benefit with synthetic mesh as opposed to biologic mesh except for mesh infection. However, under a frequentist framework, no outcome was statistically different. Conclusions: In patients undergoing open ventral hernia repair, there was no benefit for patients receiving biologic versus synthetic mesh at 24 to 36 months post-operative.

Mesh Versus No Mesh for Cruroplasty

This review describes the evolution of hiatal hernia repair for the past several decades: From the use of a primary tissue repair only, the subsequent inclusion of synthetic mesh and its complications, to current day indications for mesh use. We will highlight the recent research in biologic and composite meshes as well as the ongoing limitations in studying their efficacy. Finally, we will describe our institutional indications and surgical technique practices in the utilization of biologic mesh.

A semi-Markov model comparing the lifetime cost-effectiveness of mesh prophylaxis to prevent parastomal hernia in patients undergoing end colostomy creation for rectal cancer

AIM

Parastomal hernia (PSH) is a common problem following colostomy. Using prophylactic mesh during end colostomy creation may reduce PSH incidence, but concerns exist regarding the optimal type of mesh, potential long-term complications, and cost-effectiveness of its use. We evaluated the cost-effectiveness of mesh prophylaxis to prevent PSH in patients undergoing end colostomy creation for rectal cancer.

METHODS

We developed a decision-analytical model, stratified by rectal cancer stages I-IV, to estimate the lifetime costs, quality-adjusted life-years (QALYs) and net monetary benefits (NMBs) of synthetic, biologic and no mesh from a UK NHS perspective. We pooled the mesh-related relative risks of PSH from 13 randomised controlled trials (RCTs) and superimposed these on the baseline (no mesh) risk from a population-based cohort. Uncertainty was assessed in sensitivity analyses.

RESULTS

Synthetic mesh was less costly and more effective than biologic and no mesh to prevent PSH for all rectal cancer stages. At the willingness-to-pay threshold of £20,000/QALY, the incremental NMBs (95% CI) ranged between £1,706 (£1,692 to £1,720) (stage I) and £684 (£678 to £690) (stage IV) for synthetic versus no mesh, and £2,038 (£1,997 to £2,079) (stage I) and £1,671 (£1,653 to £1,689) (stage IV) for synthetic versus biologic mesh. Synthetic mesh was more cost-effective than no mesh unless the relative risk of PSH was ≥0.95 for stages I-III and ≥0.93 for stage IV. [Correction added on 05 October 2021 after first online publication: The estimation of health outcomes (QALYs) for all three interventions evaluated (synthetic mesh; biologic mesh; no mesh) have been corrected in this version.] CONCLUSIONS: Synthetic mesh was the most cost-effective strategy to prevent the formation of PSH in patients after end colostomy for any rectal cancer stage; however, conclusions are dependent on which subset of RCTs are considered to provide the most robust evidence.

In vivo Analysis of the Resistance of the Meshes to Escherichia coli Infection

Background: The mesh infection is mostly related to the gram-negative bacteria, such as Escherichia coli (E. coli) for emergency surgery of incarcerated hernia. However, few study investigated the effects of E. coli concentration, mesh materials and antibiotic prophylaxis on mesh infection after hernioplasty. The aim of this study was to evaluate the bacterial resistance to E. coli for three different materials of mesh, and to measure the minimum E. coli concentration for mesh infection with and without antibiotic prophylaxis in a rat model.

Methods: Three types of mesh (polytetrafluoroethylene, polypropylene, and biologic meshes) were used in the repair of an acute ventral hernia rat model in the setting of different concentrations of E. coli loads and antibiotics. At the 8th day after surgery, mesh samples were sent for microbiologic and histologic analyses.

Results: The positive rates of bacterial culture increased with E. coli concentration. The biologic mesh showed better bacterial resistance compared to polytetrafluoroethylene mesh and polypropylene mesh when the concentration of E. coli ranges from 10⁶ CFU/ml to 10⁸ CFU/ml (P = 0.002 and P = 0.029, respectively). Prophylactical ceftriaxone treatment could not decrease the colonization rate of E. coli at 10⁶ CFU/ml or 10⁸ CFU/ml in each group (P > 0.05). The scores of neovascularization in polypropylene mesh and biologic mesh were similar, which was higher than that of polytetrafluoroethylene mesh (P < 0.05). Compared with other meshes, biologic mesh showed better tolerance to 10⁶ CFU/ml E. coli with respect to inflammation, depth of inflammation, neovascularization, cellular repopulation and foreign body giant cells.

Conclusion: The biologic mesh had better E. coli resistance compared to polytetrafluoroethylene mesh and polypropylene mesh when the E. coli concentration is higher than 10⁶ CFU/ml in rats. Antibiotic prophylaxis was useful when the contamination was not particularly severe.

Long-Term Outcomes in Complex Abdominal Wall Reconstruction Repaired With Absorbable Biologic Polymer Scaffold (Poly-4-Hydroxybutyrate)

Introduction

After promising early outcomes in the use of absorbable biologic mesh for complex abdominal wall reconstruction, significant criticism has been raised over the longevity of these repairs after its 2-year resorption profile.

Methods

This is the long-term (5-year) follow-up analysis of our initial experience with the absorbable polymer scaffold poly-4-hydroxybutyrate (P4HB) mesh compared with a consecutive contiguous group treated with porcine cadaveric mesh for complex abdominal wall reconstructions. Our clinical analysis was performed using Stata 14.2 and Excel 16.16.23.

Results

After a 5-year follow-up period, the P4HB group (n = 31) experienced lower rates of reherniation (12.9% vs 38.1%; P = 0.017) compared with the porcine cadaveric mesh group (n = 42). The median interval in months to recurrent herniation was similar between groups (24.3 vs 20.8; P = 0.700). Multivariate logistic regression analysis on long-term outcomes identified smoking (P = 0.004), African American race (P = 0.004), and the use of cadaveric grafts (P = 0.003) as risks for complication while smoking (P = 0.034) and the use of cadaveric grafts (P = 0.014) were identified as risks for recurrence. The long-term cost analysis showed that P4HB had a $10,595 per case costs savings over porcine cadaveric mesh.

Conclusions

Our study identified the superior outcomes in clinical performance and a value-based benefit of absorbable biologic P4HB scaffold persisted after the 2-year resorption timeframe. Data analysis also confirmed the use of porcine cadaveric grafts independently contributed to the incidence of complications and recurrences.

Synthetic versus Biologic Mesh for Complex Open Ventral Hernia Repair: A Pilot Randomized Controlled Trial

Background: Many surgeons utilize biologic mesh for elective complex ventral hernia repair (VHR; large hernias, contaminated fields, or patients with comorbid conditions). However, no randomized controlled trials (RCTs) have compared biologic and synthetic mesh. We hypothesize biologic mesh would result in fewer major complications at one-year post-operative compared with synthetic mesh. Patients and Methods: We performed a single-center, pilot RCT. All eligible patients undergoing complex, open VHR were randomly assigned to receive biologic or synthetic mesh placed in the retromuscular position. Primary outcome was major complications, namely, a composite of mesh infection, recurrence, or re-operation at one-year post-operative. Secondary outcomes included surgical site infections (SSI), seromas, hematomas, wound dehiscence, re-admissions, and Clavien-Dindo complication grade. Outcomes were assessed using Fisher exact test and Bayesian generalized linear models. Results: Of 87 patients, 44 were randomly assigned to biologic mesh and 43 to synthetic mesh. Most cases were wound class 2-4 (68%) and 75% had a hernia width >4 cm. Most patients were obese (70%) and had an American Society of Anesthesiogists (ASA) score of 3-4 (53%). Compared with patients in the synthetic mesh group, patients in the biologic mesh group had a higher percentage of: major complications at one-year post-operative (42.4% vs. 21.6%; relative risk [RR] = 1.96 [95% confidence interval {CI} = 0.94-4.08]; number needed to harm = 4.8; p = 0.071); SSI (15.9% vs. 9.3%; RR = 1.71 [95% CI = 0.54-5.42]; p = 0.362); wound dehiscence (25.0% vs. 14.0%; RR = 1.79 [95% CI = 0.73-4.41]; p = 0.205); and re-admissions (22.7% vs 9.3%; RR = 2.44 [95% CI = 0.83-7.20]; p = 0.105). Bayesian analysis demonstrated that compared with synthetic mesh, biologic mesh had a 95% probability of increased risk of major complications at one-year post-operative. No clear evidence of a difference was found on seromas, hematomas, or Clavien-Dindo complication grade. Conclusions: In elective complex open VHR, biologic mesh demonstrated no benefit compared with synthetic mesh in one-year outcomes. Moreover, Bayesian analysis suggests that biologic mesh may have an increased probability of major complications.

Randomized Controlled Trial Of Lichtenstein Repair Of Indirect Inguinal Hernias With Two Biologic Meshes From Porcine Small Intestine Submucosa

Background

Biologic mesh is a newly developed material for hernia repairs which has been successfully used in clinical practices. This study aims to evaluate the clinical efficacy between patients undergoing a Lichtenstein’s hernioplasty with a new biologic mesh derived from porcine small intestine submucosal (SIS) extracellular matrix versus a standard SIS mesh.

Methods

A prospective, randomized, double-blinded, multi-center trial was conducted in a 6-month study. Lichtenstein hernioplasty was performed using the new SIS mesh (Beijing Biosis Healing Biotechnology) or the standard SIS mesh (Biodesign Surgisis, Cook Biotech). The postoperative follow-up examinations were carried out at during hospitalization, 1st week, 1st, 3rd, and 6th month after surgery. The primary outcome was the excellent and good rate of recovery. Secondary outcomes included recurrence rate, complications, and patient-centered outcomes.

Results

A total of 194 patients were randomized into experimental group receiving the new SIS mesh (n=97) and control group receiving the standard SIS mesh (n=97). The excellent and good rate of rehabilitation in the experimental group was 98.97%, while it was 100.00% in the control group (P>0.05). One patient had a recurrence in the experimental group, while there was no recurrence in the control group (P>0.05). Other clinical outcomes, including the length of operation or hospitalization, foreign body sensation in the inguinal area, incision healing, infection, postoperative chronic pain, postoperative allergy, hydrocele, and orchitis, were similar between the two groups.

Conclusion

Lichtenstein hernioplasty using the SIS mesh was safe and effective, and the new SIS mesh tested in this study had comparable safety and efficacy to the wildly used SIS mesh.

Biologic Mesh Underlay in Thoracoscopic Primary Repair of Congenital Diaphragmatic Hernia Confers Reduced Recurrence in Neonates: A Preliminary Report

Purpose: The purpose of this study was to determine if utilization of biologic mesh underlay during thoracoscopic congenital diaphragmatic hernia (CDH) primary repair (PR) results in reduced 5-year hernia recurrence rates. Methods: A retrospective review was completed for all primarily repaired CDH utilizing a thoracoscopic approach from January 1, 2003 to June 31, 2013. Patients were included in the study cohort if they had a thoracoscopic PR of their CDH without any mesh reinforcement or with biologic mesh underlay. Charts were then reviewed for no less than 5 years postoperatively for reports of clinical and/or radiographic hernia recurrence. The cumulative annual hernia recurrence as well as other demographic factors were analyzed. Results: Within the study period, 46 patients were identified that met study criteria. Three patients were lost to follow-up. Fifteen of the remaining patients (15/43: 34.9%) had a biologic underlay. Within the cohort, seven recurrences were noted within 5 years of the index procedure (7/43; 16.7%). Four recurrences occurred within the first postoperative year, and all occurred by the third postoperative year. One recurrence was in a patient with a biologic underlay at 4 months after repair. This was a clinically/radiographically silent 4 mm defect and noted at laparoscopy for another indication (1/15: 6.6%). The remainder occurred in primarily repaired patients without mesh reinforcement (6/28: 21.4%). Conclusions: Thoracoscopic PR of CDH can be successfully performed in select patients. The use of a biologic mesh underlay in this subset of patients appears to confer reduced hernia recurrence.

Performance of biological mesh materials in abdominal wall reconstruction: study protocol for a randomised controlled trial

INTRODUCTION

Abdominal wall hernias are a common source of morbidity and mortality. The use of biological mesh has become an important adjunct in successful abdominal wall reconstruction. There are a variety of biological mesh products available; however, there is limited evidence supporting the use of one type over another. This study aims to compare the performance (eg, the rate of hernia recurrence) of either a crosslinked biological mesh product or a non-crosslinked product in patients undergoing abdominal wall reconstruction.

METHODS AND ANALYSIS

This is a single-centre, dual arm randomised controlled trial. Patients requiring abdominal wall reconstruction will be assessed for eligibility. Eligible patients will then undergo an informed consent process following by randomisation to either (1) crosslinked porcine dermis mesh (Permacol); or (2) non-crosslinked porcine dermis mesh (Strattice). These groups will be compared for the rate of hernia recurrence at 1 and 2 years as well as the rate of postoperative complications (eg, surgical site infections).

ETHICS AND DISSEMINATION

This study has been approved by the institution's research ethics board and registered with clinicaltrials.gov. All eligible participants will provide informed consent prior to randomization. The results of this study may help guide the choice of biologic mesh for this population. The results of this study will be published in peer-reviewed journals as well as national and international conferences.

TRIAL REGISTRATION NUMBER

NCT02703662.

Biological implant-associated granulomatous inflammation resulting in secondary hypercalcemia and azotemia in a dog

Implant associated granulomatous inflammation causing hypercalcemia can occur following use of commercial xenogeneic pericardial tissue patches in dogs. Removal of the implant can result in resolution of the hypercalcemia, suggesting a causal relationship between the tissue reaction to a xenogeneic implant and development of hypercalcemia.

Abdominal Wall Reconstruction: An Integrated Approach

Abdominal wall reconstruction has undergone substantial evolution over the last few decades. The optimal method of repair should be tailored to each patient's unique condition; however, a general approach that integrates four major factors can be applied as a conceptual framework to most clinical scenarios. Major factors to be considered include selection of mesh material, mesh inset position and technique, selective component separation, and management of soft tissue. These topics are inextricably intertwined in the sense that each can have specific implications, and in some cases, a determinative impact on the other decisions. When the relationship among these four factors is appreciated and applied to patient management, the reconstructive surgeon can achieve consistent outcomes that reflect skill, experience, and understanding.

Reconstruction of an abdominal wall defect with biologic mesh after resection of a desmoid tumor in a patient with a Gardner's syndrome

INTRODUCTION

Desmoid tumors are rare proliferative and invasive benign lesions. They can be sporadic, but in most instances, desmoid tumors develop in the context of Gardner's syndrome with principal localization in the abdominal cavity and abdominal wall.

CASE-REPORT

We report the case of a 24-year-old female presenting Gardner's syndrome with a symptomatic abdominal wall desmoid tumor. Lack of response to medical treatment led to surgical management consisting in a complete resection and parietal reconstruction with a biologic mesh. Postoperative course was uneventful and there was no evidence of recurrence at 12 months of follow-up.

DISCUSSION

Conventional treatment of abdominal wall desmoid tumors consists in a wide and radical resection. However, complete resection is not always feasible because of difficulty to differentiate the desmoid tumor from adjacent tissues. The surgical approach may require different techniques to repair the parietal defect including prosthetic material such as synthetic or biologic meshes. Biological mesh is an ideal alternative to synthetic graft, mainly in case of infection.

CONCLUSION

We have encountered a case of a symptomatic growing desmoid tumor of the abdominal wall in a young patient with Gardner's syndrome, successfully treated by complete resection and reconstruction with a biologic mesh to correct the parietal defect.

Laparoscopic Hiatal Hernia Repair in 221 Patients: Outcomes and Experience

BACKGROUND AND OBJECTIVES

Hiatal hernia is a common condition often associated with symptomatic gastroesophageal reflux disease (GERD). The objectives of this study were to examine the efficacy and safety of laparoscopic hiatal hernia repair (LHHR) with biologic mesh to reduce and/or alleviate GERD symptoms and associated hiatal hernia recurrence.

METHODS

We retrospectively reviewed consecutive LHHR procedures with biologic mesh performed by a single surgeon from July 2009 to October 2014. The primary efficacy outcome measures were relief from GERD symptoms, as measured according to the GERD-health-related quality-of-life (GERD-HRQL) scale and hiatal hernia recurrence. A secondary outcome measure was overall safety of the procedure.

RESULTS

A total of 221 patients underwent LHHR with biologic mesh during the study period, and pre- and postoperative GERD-HRQL studies were available for 172 of them. At baseline (preoperative), the mean GERD-HRQL score for all procedures was 18.5 ± 14.4. At follow-up (mean, 14.5 ± 11.0 months [range, 2.0-56.0]), the score showed a statistically significant decline to a mean of 4.4 ± 7.5 (P < .0001). To date, 8 patients (3.6%, 8/221) have had a documented anatomic hiatal hernia recurrence. However, a secondary hiatal hernia repair reoperation was necessary in only 1 patient. Most complications were minor (dysphagia, nausea and vomiting). However, there was 1 death caused by a hemorrhage that occurred 1 week after surgery.

CONCLUSIONS

Laparoscopic hiatal hernia repair using biologic mesh, both with and without a simultaneous bariatric or antireflux procedure, is an efficacious and safe therapeutic option for management of hiatal hernia, prevention of recurrence, and relief of symptomatic GERD.

Repair of Perineal Hernia Following Abdominoperineal Excision with Biological Mesh: A Systematic Review

Introduction

Perineal hernia (PerH) following abdominoperineal excision (APE) procedure is a recognized complication. PerH was considered an infrequent complication of APE procedure; however, PerH rates of up to 45% have been reported in recent publications following a laparoscopic APE procedure. Various methods of repair of PerH with the use of synthetic meshes or myocutaneous flap have been described, although there is no general agreement on an optimal strategy. The use of biological meshes for different operations is growing in popularity, and these have been promoted as being superior and safer when compared to synthetic meshes. Although the use of biologics is becoming popular claims of better outcomes are largely unsupported by evidence. The aim of this systematic review is to evaluate the currently available evidence supporting the use of biologic or biosynthetic meshes for the repair of PerH that develop following an APE.

Methods

A systematic review of all English language literature relevant to repair of PerH following APE with biologic or biosynthetic mesh published between January 1, 2000 and July 31, 2016 was carried out using MEDLINE, EMBASE, and the Cochrane Library of Systematic Reviews for relevant literature. Searches were performed using a combination of Medical Subject Headings (MeSH) terms and text words “PerH,” “APE,” “morbidity,” “biologics,” “biosynthetic,” and “hernia.” Studies in which the use of biological meshes was not reported were excluded from the review. Various outcome measures, including operative technique, complication rates, recurrence rates, type of mesh, management of recurrences, and risk factors, were extracted. Oxford Centre for Evidence-based Medicine – Levels of Evidence (March 2009) was used to assess the quality of evidence.

Results

The systematic review of the literature identified three case reports, four case series, and one pooled analysis that were included in the final review. Overall, these studies were of poor quality providing level 4 evidence. Various different approaches and techniques of repair of PerH were described; however, it was difficult to extract information with regard to the primary and secondary outcome measures.

Conclusion

There is no general agreement to the optimal operative strategy to repair PerH following an APE. There is insufficient evidence to recommend any specific operative approach or repair technique for PerH following an APE.

Functional Results after Repair of Large Hiatal Hernia by Use of a Biologic Mesh

BACKGROUND

The aim of this observational study is to analyze the results of patients with large hiatal hernia and upside-down stomach after surgical closure with a biological mesh (Permacol(®), Covidien, Neustadt an der Donau, Germany). Biological mesh is used to prevent long-term detrimental effects of artificial meshes and to reduce recurrence rates.

METHODS

A total of 13 patients with a large hiatal hernia and endothoracic stomach, who underwent surgery between 2010 and 2014, were included. Interviews and upper endoscopy were conducted to determine recurrences, lifestyle restrictions, and current complaints.

RESULTS

After a mean follow-up of 26 ± 18 months (range: 3-58 months), 10 patients (3 men, mean age 73 ± 13, range: 26-81 years) were evaluated. A small recurrent axial hernia was found in one patient postoperatively. Dysphagia was the most common complaint (four cases); while in one case, the problem was solved after endoscopic dilatation. In three cases, bloat and postprandial pain were documented. In one case, an explantation of the mesh was necessary due to mesh migration and painful adhesions. In one further case with gastroparesis, pyloroplasty was performed without success. The data are compared to the available literature. It was found that dysphagia and recurrence rates are unrelated both in biological and in synthetic meshes if the esophagus is encircled. In series preserving the esophagus at least partially uncoated, recurrences after the use of biological meshes relieve dysphagia. After the application of synthetic meshes, dysphagia is aggravated by recurrences.

CONCLUSION

Recurrence is rare after encircling hiatal hernia repair with the biological mesh Permacol(®). Dysphagia, gas bloat, and intra-abdominal pain are frequent complaints. Despite the small number of patients, it can be concluded that a biological mesh may be an alternative to synthetic meshes to reduce recurrences at least for up to 2 years. Our study demonstrates that local fibrosis and thickening of the mesh can affect the outcome being associated with abdominal discomfort despite a successful repair. The review of the literature indicates comparable results after 2 years with both biologic and synthetic meshes embracing the esophagus. At the same point in time, reconstruction with synthetic and biologic materials differs when the esophagus is not or only partially encircled in the repair. This is important since encircling artificial meshes can erode the esophagus after 5-10 years.

Prevention of a Parastomal Hernia by Biological Mesh Reinforcement

Introduction

In the field of hernia prevention, the prophylactic mesh-reinforcement of stoma-sites is one of the most controversially discussed issues. The incidence of parastomal hernias in the literature reported to be up to 48.1% after end colostomy and up to 30.8% after loop of colostomy, but still remains uncertain due to diagnostic variety of clinical or radiological methods, heterogeneous patient groups and variable follow-up intervals. Anyway, the published data regarding the use of synthetic or bio-prostethic meshes in the prevention of parastomal hernia at the primary operation are very scarce.

Methods

A literature search of the Medline database in terms of biological prophylactic mesh implantation in stoma creation identified six systematic reviews, two randomized controlled trials (RCT), two case-controlled studies, and one technical report.

Results

In a systematic review focusing on the prevention of parastomal hernia including only RCTs encompassing one RCT using bio-prosthetic mesh the incidence of herniation was 12.5% compared to 53% in the control group (p < 0.0001). In one RCT and two case-control studies, respectively, there was a significant smaller incidence of parastomal herniation as well as a similar complication rate compared to the control group. Only in one RCT, no significant difference regarding the incidence of parastomal hernia was reported with comparable complication rates.

Conclusion

Thus, so far two RCT and two case-control studies are published with prophylactic bio-prosthetic reinforcement in stoma sites. The majority revealed significant better results in terms of parastomal herniation and without any mesh-related complications in comparison to the non mesh group. Further, multicenter RCT are required to achieve a sufficient level of recommendation.

The Use of Biological Meshes in Diaphragmatic Defects - An Evidence-Based Review of the Literature

The widespread use of meshes for hiatal hernia repair has emerged in the era of laparoscopic surgery, although sporadic cases of mesh augmentation of traumatic diaphragmatic rupture have been reported. The indications for biologic meshes in diaphragmatic repair are ill defined. This systematic review aims to investigate the available evidence on the role of biologic meshes in diaphragmatic rupture and hiatal hernia repair. Limited data from sporadic case reports and case series have demonstrated that repair of traumatic diaphragmatic rupture with biologic mesh is safe technique in both the acute or chronic setting. High level evidence demonstrates short-term benefits of biologic mesh augmentation in hiatal hernia repair over primary repair, although adequate long-term data are not currently available. Long-term follow-up data suggest no benefit of hiatal hernia repair using porcine small intestine submucosa over suture repair. The effectiveness of different biologic mesh materials on hernia recurrence requires further investigation.

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.

Parastomal hernia repair and reinforcement: the role of biologic and synthetic materials

Parastomal hernia is a prevalent problem and treatment can pose difficulties due to significant rates of recurrence and morbidities of the repair. The current standard of care is to perform parastomal hernia repair with mesh whenever possible. There exist multiple options for mesh reinforcement (biologic and synthetic) as well as surgical techniques, to include type of repair (keyhole and Sugarbaker) and position of mesh placement (onlay, sublay, or intraperitoneal). The sublay and intraperitoneal positions have been shown to be superior with a lower incidence of recurrence. This procedure may be performed open or laparoscopically, both having similar recurrence and morbidity results. Prophylactic mesh placement at the time of stoma formation has been shown to significantly decrease the rates of parastomal hernia formation.

Biomaterials in the treatment of anal fistula: hope or hype?

Anal fistula (AF) presents a chronic problem for patients and colorectal surgeons alike. Surgical treatment may result in impairment of continence and long-term risk of recurrence. Treatment options for AFs vary according to their location and complexity. The ideal approach should result in low recurrence rates and minimal impact on continence. New technical approaches involving biologically derived products such as biological mesh, fibrin glue, fistula plug, and stem cells have been applied in the treatment of AF to improve outcomes and decrease recurrence rates and the risk of fecal incontinence. In this review, we will highlight the current evidence and describe our personal experience with these novel approaches.

The role of synthetic and biologic materials in the treatment of pelvic organ prolapse

Pelvic organ prolapse is a significant medical problem that poses a diagnostic and management dilemma. These diseases cause serious morbidity in those affected and treatment is sought for relief of pelvic pain, rectal bleeding, chronic constipation, obstructed defecation, and fecal incontinence. Numerous procedures have been proposed to treat these conditions; however, the search continues as colorectal surgeons attempt to find the procedure that would optimally treat these conditions. The use of prosthetics in the repair of pelvic organ prolapse has become prevalent as the benefits of their use are realized. While advances in biologic mesh and new surgical techniques promise improved functional outcomes with decreased complication rates without de novo symptoms, the debate concerning the best prosthetic material, synthetic or biologic, remains controversial. Furthermore, laparoscopic ventral mesh rectopexy has emerged as a procedure that could potentially fill this role and is rapidly becoming the procedure of choice for the surgical treatment of pelvic organ prolapse.

Biomaterials: so many choices, so little time. What are the differences?

The use of biologic mesh has increased greatly in recent years in response to the need for a solution in managing contaminated hernias. Multiple different meshes are commercially available, and are derived from a variety of sources, including human dermis as well as animal sources. For a mesh to be effective, it must be resistant to infection, have adequate tensile strength for hernia repair, and be well tolerated by the host. To achieve this end, biologic meshes go through an intense processing that varies from one product to the next. In this article, the authors review the types of mesh available, how they are processed, and examine these characteristics in terms of their strengths and weaknesses in application to surgical technique.

Onlay ventral hernia repairs using porcine non-cross-linked dermal biologic mesh

INTRODUCTION

Ventral hernias are common and repair with mesh has been shown to reduce recurrence. However, synthetic mesh is associated with a risk of infection. Biologic mesh is an alternative that may be less susceptible to infection. Typically, the sublay position is preferred for mesh placement but this technique takes longer and has not been shown to have a lower recurrence rate than an onlay mesh. The aim of this study was to evaluate the outcome of complex ventral hernia repair using a porcine non-cross-linked biologic mesh onlay.

METHODS

A retrospective chart review was performed of all patients that had a ventral hernia repair with biologic mesh from January 2009 to March 2012. The operative procedure in all patients was an open repair with primary fascial closure (if possible) with or without external oblique component separation and porcine biologic mesh onlay.

RESULTS

There were 22 patients that had a ventral hernia repair, 19 primary and 3 recurrent. The majority were men, had hernia grade 3 or 4, and developed the hernia after an esophagectomy or gastrectomy for cancer. All but one had primary closure with a porcine biologic mesh onlay. One patient was bridged for loss of domain. A bilateral external oblique component separation was added in 16 patients (73 %). The median hospital stay was 7 days. There were two superficial wound infections, one with exposed mesh, but no patient required mesh removal. A seroma requiring intervention developed in 6 patients (27 %) and resolved with pig-tail drainage. At a median follow-up of 7 months, there has been no hernia recurrence apart from the patient that was bridged.

CONCLUSIONS

Porcine non-cross-linked biologic mesh overlay has excellent short-term results in patients at increased risk for mesh infection. No patient required mesh removal, and there have been no recurrent hernias in patients with primary fascial closure. Biologic bridging is not effective for long-term abdominal wall reconstruction.

Hiatal hernia repair with biologic mesh reinforcement reduces recurrence rate in small hiatal hernias

The utility of mesh reinforcement for small hiatal hernia found especially during antireflux surgery is unknown. Initial reports for the use of biological mesh for crural reinforcement during repair for defects greater than 5 cm have been shown to decrease recurrence rates. This study compares patients with small hiatal hernias who underwent onlay biologic mesh buttress repair versus those with suture cruroplasty alone. This is a single-institution retrospective review of all patients undergoing repair of hiatal hernia measuring 1-5 cm between 2002 and 2009. The patients were evaluated based on surgical repair: one group undergoing crural reinforcement with onlay biologic mesh and other group with suture cruroplasty only. Seventy patients with hiatal hernia measuring 1-5 cm were identified. Thirty-eight patients had hernia repair with biologic mesh, and 32 patients had repair with suture cruroplasty only. Recurrence rate at 1 year was 16% (5/32) in patients who had suture cruroplasty only and 0% (0/38) in the group with crural reinforcement with absorbable mesh (statistically significant, P = 0.017). Suture cruroplasty alone appears to be inadequate for hiatal hernias measuring 1-5 cm with significant recurrence rate and failure of antireflux surgery. Crural reinforcement with absorbable mesh may reduce hiatal hernia recurrence rate in small hiatal hernias.

Porcine incisional hernia model: Evaluation of biologically derived intact extracellular matrix repairs

We compared fascial wounds repaired with non-cross-linked intact porcine-derived acellular dermal matrix versus primary closure in a large-animal hernia model. Incisional hernias were created in Yucatan pigs and repaired after 3 weeks via open technique with suture-only primary closure or intraperitoneally placed porcine-derived acellular dermal matrix. Progressive changes in mechanical and biological properties of porcine-derived acellular dermal matrix and repair sites were assessed. Porcine-derived acellular dermal matrix–repaired hernias of additional animals were evaluated 2 and 4 weeks post incision to assess porcine-derived acellular dermal matrix regenerative potential and biomechanical changes. Hernias repaired with primary closure showed substantially more scarring and bone hyperplasia along the incision line. Mechanical remodeling of porcine-derived acellular dermal matrix was noted over time. Porcine-derived acellular dermal matrix elastic modulus and ultimate tensile stress were similar to fascia at 6 weeks. The biology of porcine-derived acellular dermal matrix–reinforced animals was more similar to native abdominal wall versus that with primary closure. In this study, porcine-derived acellular dermal matrix–reinforced repairs provided more complete wound healing response compared with primary closure.

Abdominal wall reconstruction with mesh and components separation

Incisional hernias in the abdominal wall are a by-product of multiple previous laparotomies. Unfortunately, the incidence of incisional hernias has risen, as we have progressed with new surgical techniques in the treatment of abdominal pathologies. Many methods have been attempted in the past to achieve a better and more durable repair, namely using components separation to bring the fascia into the midline, and reinforce incisional hernias with different mesh materials. The authors review the recent literature regarding the efficacy of these synthetic materials and biomaterials in incisional hernia repair, as well as share their experience in treating complex abdominal wall defects using components separation and biologic mesh.

Lateral abdominal wall reconstruction

Lateral abdominal wall (LAW) defects can manifest as a flank hernias, myofascial laxity/bulges, or full-thickness defects. These defects are quite different from those in the anterior abdominal wall defects and the complexity and limited surgical options make repairing the LAW a challenge for the reconstructive surgeon. LAW reconstruction requires an understanding of the anatomy, physiologic forces, and the impact of deinnervation injury to design and perform successful reconstructions of hernia, bulge, and full-thickness defects. Reconstructive strategies must be tailored to address the inguinal ligament, retroperitoneum, chest wall, and diaphragm. Operative technique must focus on stabilization of the LAW to nonyielding points of fixation at the anatomic borders of the LAW far beyond the musculofascial borders of the defect itself. Thus, hernias, bulges, and full-thickness defects are approached in a similar fashion. Mesh reinforcement is uniformly required in lateral abdominal wall reconstruction. Inlay mesh placement with overlying myofascial coverage is preferred as a first-line option as is the case in anterior abdominal wall reconstruction. However, interposition bridging repairs are often performed as the surrounding myofascial tissue precludes a dual layered closure. The decision to place bioprosthetic or prosthetic mesh depends on surgeon preference, patient comorbidities, and clinical factors of the repair. Regardless of mesh type, the overlying soft tissue must provide stable cutaneous coverage and obliteration of dead space. In cases where the fasciocutaneous flaps surrounding the defect are inadequate for closure, regional pedicled flaps or free flaps are recruited to achieve stable soft tissue coverage.