Randomized clinical trial comparing lightweight composite mesh with polyester or polypropylene mesh for incisional hernia repair

Randomized clinical trial comparing inguinal hernia repair with Lichtenstein technique using non-absorbable or partially absorbable mesh. Preliminary report

INTRODUCTION

The Lichtenstein technique is currently considered the "gold standard" of open, anterior inguinal hernia repair. It is not free, however, of adverse effects, which may be caused by the implemented synthetic material.

AIM

Determination the influence of the mesh employed on treatment results including immediate complications, return to everyday activities, chronic pain occurrence and hernia recurrence.

MATERIAL AND METHODS

Tension-free hernia repair using the Lichtenstein technique was performed in all the 59 patients randomized to trial groups. Group P with heavyweight polypropylene mesh contained 34 patients; group V with lightweight, partially absorbable mesh (polypropylene/polyglactin 910) consisted of 25 people. Controlled, scheduled follow-up appointments took place after the 7(th) day and the 3(rd) and 6(th) month. Patients were clinically assessed and pain intensity was determined on an analogue-visual scale.

RESULTS

No statistically significant influence of the type of mesh on the risk of early complications, severe pain intensity, the length of hospital stay, time of recovery, or patients' satisfaction with treatment was observed. After 6 months also no statistically significant differences were observed between groups with regard to recurrence rate (P 3.4% vs. V 4.0%), chronic pain (P 5.9% vs. V 4.0%) and ailments such as "foreign body presence" (V vs. P, OR = 0.30, 95% CI 0.077-1.219, p = 0.093) incidence, although their probability was 70% lower for V mesh.

CONCLUSIONS

The preliminary results confirm the effectiveness of the Lichtenstein technique for hernia repair with both types of meshes. It appears that use of a partially absorbable mesh is connected with lower risk of postoperative complications, but the final results require multicentre trials in a larger series of patients.

Long term outcome and quality of life after open incisional hernia repair--light versus heavy weight meshes

Background

Mesh repair of incisional hernia is superior to the conventional technique. From all available materials for open surgery polypropylene (PP) is the most widely used. Development resulted in meshes with larger pore size, decreased mesh surface and lower weight. The aim of this retrospective non randomized study was to compare the quality of life in the long term follow up (> 72 month) after incisional hernia repair with "light weight"(LW) and "heavy weight"(HW) PP meshes.

Methods

12 patients who underwent midline open incisional hernia repair with a HW-PP mesh (Prolene^® 109 g/m² pore size 1.6 mm) between January 1996 and December 1997 were compared with 12 consecutive patients who underwent the same procedure with a LW-PP mesh (Vypro^® 54 g/m², pore size 4-5 mm) from January 1998. The standard technique was the sublay mesh-plasty with the retromuscular positioning of the mesh. The two groups were equal in BMI, age, gender and hernia size. Patients were routinely seen back in the clinic.

Results

In the long term run (mean follow up 112 ± 22 months) patients of the HW mesh group revealed no significant difference in the SF-36 Health Survey domains compared to the LW group (mean follow up 75 ± 16 months).

Conclusions

In this study the health related quality of life based on the SF 36 survey after open incisional hernia repair with light or heavy weight meshes is not related to the mesh type in the long term follow up.

A new prosthetic implant for inguinal hernia repair: its features in a porcine experimental model

Even after more than 100 years of inguinal hernia repair, the rate of complications and recurrence remains unacceptably high. In the last decades, few effective advances in surgical technique and materials have been made. The authors see them as minor adjustments in the shape and materials of the prosthetic implants. Still, the underlying genesis of inguinal hernia remains undefined. Based upon this, it seems the surgical repair of inguinal protrusions cannot be based upon the pathogenesis because the etiology to date has not been addressed. Most hernia repairs are performed with some degree of point fixation (sutures/tacks) to stop the mesh from migrating and creating high recurrence rates. This should be a priority for our considerations, as fixating mesh puts it in stark contrast to the physiology and dynamics of the myotendineal structures of the groin. Following years of surgical practice, implant fixation, mesh shrinkage, and poor quality of tissue ingrowth still represent an unresolved issue in modern hernia repair. Conventional prosthetics used for inguinal hernia repair are static and passive. They do not move in harmony with the dynamic elements of the groin structure and, as a result, induce the ingrowth of thin scar plates or shrinking regressive tissue that colonizes the implants. The authors strongly believe that these characteristics may be a contributing factor for recurrences and patient discomfort. Other complications are reported in the literature to be a direct result of fixation of the implants, such as bleeding, nerve entrapment, hematoma, pain, discomfort, and testicular complications. To improve results by respecting the physiology and kinetics of the inguinal region, we felt that a new type of prosthesis should be designed that induces a more structured tissue ingrowth similar to the natural biologic components of the abdominal wall. This prosthetic device was specifically designed to be placed with no point fixation. This was achieved by using inherent radial recoil, vertical buffering, friction, and delivering the device in a constrained state. A secondary benefit of this "dynamic" design is that the implant moves in a three-dimensional way in unison with the movements of the myotendineal structures of the groin. The results appear to show that the three-dimensional structure not only acts as a suitable scaffold for a full thickness ingrowth of a tissue barrier but also seems to induce an ordered, supple, elastic tissue, which allows for neorevascularization and neoneural growth. The outcomes indicate a reduced impact of fibrotic shrinkage on the implant/scar tissue when compared with shrinkage of polypropylene meshes reported in the literature. This pilot study shows the features of such an implant in a porcine experimental model.

A randomised, multi-centre, prospective, double blind pilot-study to evaluate safety and efficacy of the non-absorbable Optilene Mesh Elastic versus the partly absorbable Ultrapro Mesh for incisional hernia repair

Background

Randomised controlled trials with a long term follow-up (3 to 10 years) have demonstrated that mesh repair is superior to suture closure of incisional hernia with lower recurrence rates (5 to 20% versus 20 to 63%). Yet, the ideal size and material of the mesh are not defined. So far, there are few prospective studies that evaluate the influence of the mesh texture on patient's satisfaction, recurrence and complication rate. The aim of this study is to evaluate, if a non-absorbable mesh (Optilene^® Mesh Elastic) will result in better health outcomes compared to a partly absorbable mesh (Ultrapro^® Mesh).

Methods/Design

In this prospective, randomised, double blind study, eighty patients with incisional hernia after a midline laparotomy will be included. Primary objective of this study is to investigate differences in the physical functioning score from the SF-36 questionnaire 21 days after mesh insertion. Secondary objectives include the evaluation of the patients' daily activity, pain, wound complication and other surgical complications (hematomas, seromas), and safety within six months after intervention.

Discussion

This study investigates mainly from the patient perspective differences between meshes for treatment of incisional hernias. Whether partly absorbable meshes improve quality of life better than non-absorbable meshes is unclear and therefore, this trial will generate further evidence for a better treatment of patients.

Trial registration

NCT00646334

One-year follow-up after incisional hernia treatment: results of a prospective randomized study

BACKGROUND

The incidence of incisional hernia after midline laparotomies ranges from 10 to 20%. The recurrence rate after this hernia surgery varies from 25 to 52% using autogenous tissue. The use of prosthetic meshes can decrease the postoperative hernia recurrence by up to 10%. The aim of this prospective randomized clinical study was to analyze and compare the results of three different incisional hernia surgical techniques.

MATERIALS AND METHODS

One hundred and sixty-one patients who underwent incisional hernia surgery were randomized into three groups. The Keel technique was used in the first group, the "Onlay" technique (prosthetic mesh is fixed on the external abdominal muscle slip) in the second group, and the "Sublay" technique (prosthetic mesh is placed on the posterior abdominal muscle sheath) in the third group. Age, sex, hospitalization time, body mass index (BMI), intraabdominal pressure, postoperative complications, postoperative pain, normal physical activity recovery time, and recurrence rate were compared between the groups. The postoperative follow-up period was 12 months.

RESULTS

Fifty-four patients in the Keel group, 57 patients in the "Onlay" group, and 50 patients in the "Sublay" group were operated. Age, hospitalization time, and BMI were similar in all of the groups. The operative time was significantly longer in the prosthetic mesh groups compared with the Keel group. The intraabdominal pressure changes before and after surgery was significantly higher in the Keel group compared with the prosthetic mesh groups (5.66 ± 2.5 mmHg vs. 1.88 ± 1 mmHg vs. 1.76 ± 1 mmHg; P < 0.05). The postoperative wound complications rate was significantly higher in the "Onlay" technique group compared with the Keel and "Sublay" technique groups (49.1% vs. 22.2% vs. 24%; P < 0.05). Postoperative pain (VAS score) was significantly lower in the "Onlay" and "Sublay" groups (5.53 ± 1.59 vs. 3.96 ± 1.56 vs. 3.78 ± 1.97; P < 0.05). All of the patients in "Sublay" group recovered to normal physical activity during the 6 months follow-up period compared with 94.4% of patients in the Keel group and 98.3% of patients in the "Onlay" group. The recurrence rate was 22.2% in the Keel group, 10.5% in the "Onlay" group, and 2% in the "Sublay" group during the follow-up period. The general complications rate after hernia surgery was 5.6%. Postoperative pneumonia was the most frequent complication, which appeared in 4.3% of patients. There was no postoperative death in our prospective study.

CONCLUSIONS

Mesh repair is the first-choice technique for incisional hernia treatment. The results of the "Sublay" technique are better than the "Onlay" technique.

The comparison of heavyweight mesh and lightweight mesh in an incisional animal model

PURPOSE

An incisional hernia may occur through the incision area following a surgical operation, through the trocar opening and even through drainage exit points. Various synthetic surgical meshes have recently been used for the surgical repair of incisional hernias. In this study, we analysed the burst strength forces of heavyweight mesh and lightweight mesh in an incisional animal model.

METHODS

Following experimental formation of incisional hernias in 32 Wistar albino rats, they were divided into four groups. Polypropylene suture was used for closure of the abdominal incision in Group 1. In Groups 2, 3 and 4, polyester, polypropylene + polyglactin and polypropylene meshes, respectively, were fixed on the surface of the fascia after closing the defects in the rats. Polypropylene and polyester meshes are classified as heavy mesh. Light mesh is composed of a non-absorbable part (polypropylene) and an absorbable part (polyglactin), which will disappear 80 days after implantation. The rats were sacrificed at the end of the experiment. The pullout force of the fascia and meshes were recorded by use of a digital tension meter.

RESULTS

The mean pullout forces for Groups 1, 2, 3 and 4 were found to be 123.4 +/- 13.3, 292.33 +/- 17.4, 281.66 +/- 16.3 and 310.60 +/- 26.1 N, respectively.

CONCLUSION

At the end of the experiment, the polypropylene (25 g/cm(2)) present in the lightweight mesh was found to lose only a small percentage of the burst strength compared to the polypropylene (85 g/cm(2)) present in the heavyweight mesh.

Impact of mesh positioning on foreign body reaction and collagenous ingrowth in a rabbit model of open incisional hernia repair

BACKGROUND

Incisional hernia remains as one of the most common surgical complications. Different mesh techniques are used in 75-80% of hernia repair. The aim of this study was to evaluate the dependence of mesh positioning and the type of mesh implanted on foreign body reaction and collagenous ingrowth.

MATERIALS AND METHODS

In 24 male Chinchilla rabbits, an incisional hernia repair was performed with mesh reinforcement either by sublay (n = 12) or by onlay technique (n = 12). In each group, two different types of mesh prosthesis were investigated: polypropylene (PP, Prolene) and polypropylene-polyglecaprone 25 composite (PP-PG, UltraPro). On postoperative day 60, the inflammatory and connective tissue formation was characterised by measuring the diameter of inner cellular infiltrate and outer fibrous capsule of the foreign body granuloma, and by verifying the collagen type I/III ratio. Furthermore, the expression of matrix metalloproteinase-2 (MMP-2) was analysed.

RESULTS

Microscopic investigation of the mesh/host-tissue interface showed typical formation of foreign body granuloma. The diameters of the inner part of the foreign body granuloma representing the amount of inflammatory cell infiltrate were significantly increased in the PP mesh compared to the PP-PG mesh, both in the sublay group (PP 13.1 +/- 1.21 microm vs. PP-PG 11.7 +/- 0.34 microm; P = 0.026) and in the onlay group (PP 13.1 +/- 1.24 microm vs. PP-PG 11.2 +/- 0.55 microm; P = 0.009). The diameter of the fibrous capsule as the outer ring of the granuloma was significantly increased when investigating the PP mesh in sublay position (29.5 +/- 1.12 microm) compared to the PP mesh in onlay position (27.9 +/- 0.73 microm) (P = 0.026). Investigating the quality of perifilamentary collagen deposition expressed as collagen type I/III ratio, the sublay group showed significantly elevated values compared to the onlay group (PP sublay 3.1 +/- 0.18 vs. PP onlay 2.4 +/- 0.41; P = 0.004) (PP-PG sublay 3.5 +/- 0.34 vs. PP-PG onlay 2.6 +/- 0.13; P = 0.002). The analysis of MMP-2 expression revealed no significant differences.

CONCLUSION

The beneficial results of mesh reinforcement in the sublay technique might be due to a superior quality of postoperative connective tissue formation. Mesh incorporation, irrespective of positioning, is favourable in low-weight, large, porous mesh material represented by a reduced inflammatory part of the foreign body granuloma.

Comparing the behavior of different polypropylene meshes (heavy and lightweight) in an experimental model of ventral hernia repair

New generation prosthetic biomaterials for abdominal wall repair have been designed to be less dense, by having larger pores than that of the standard polypropylene meshes, to improve abdominal wall compliance. The aim of the present study was to analyze the functional and morphologic properties of these new meshes. For this purpose, 7 x 5 cm(2) defects were created in the anterior abdominal wall of 36 male New Zealand White rabbits and repaired using different polypropylene meshes: a heavyweight mesh (HW), Surgipro, and two lightweight meshes (LW), Parietene and Optilene. Six animals each implanted with biomaterial were sacrificed on postoperative days 14 and 90. Histological and morphometric analysis, adhesion assessment, and biomechanical resistance tests were performed. Similar behavior was shown by the LW and HW meshes in terms of the adhesions and macrophage response induced. After 14 days, the tensile strength of Optilene was greater than the strengths recorded for the other two biomaterials, probably because of its high elasticity. By 90 days, however, the tensile strengths of the three biomaterials were comparable. In conclusion, despite an initial tensile strength advantage shown by the mesh with larger pores, at 90 days postimplant, tensile strengths were similar. Compared with HW, LW prostheses have the benefit that less foreign material was implanted, preserving the elasticity of the recipient host tissue.

Randomized, controlled, prospective trial of the use of a mesh to prevent parastomal hernia

BACKGROUND

The prevalence of terminal parastomal hernia (PH) after colostomy placement may be as high as 50%. The effect of the PH may range from discomfort to life-threatening complications. Surgical procedures for repairing PH are difficult to perform and present a high-failure rate.

OBJECTIVE

To reduce the incidence of PH by implanting a lightweight mesh in the sublay position.

MATERIAL AND METHODS

Randomized, controlled, prospective study. Patients were scheduled for permanent end colostomy surgery to treat cancer of the lower third of the rectum, performed by the same colorectal surgery team. An Ultrapro lightweight mesh was inserted in the sublay position in the study group. Using simple randomization, the sample size required was estimated to be 27 per group. Patients were followed-up clinically and radiologically with abdominal computed tomography by an independent clinician and a radiologist who were all blind to the aims of the study, 1 month and every 6 months after surgery.

RESULTS

: The groups were homogeneous in terms of their clinical and demographic characteristics. Surgical time and postoperative morbidity were similar in the 2 groups. Mortality was 0. No mesh intolerance was reported. In the clinical follow-up (median: 29 months, range: 13-49), 11/27 (40.7%) hernias were recorded in the control group compared with 4/27 (14.8%) in the study group (P = 0.03). Abdominal computed tomography identified 14/27 (44.4%) hernias in the control group compared with 6/27 (22.2%) in the study group (P = 0.08).

CONCLUSIONS

Parastomal placement of a mesh reduces the appearance of PH. The technique is safe, well-tolerated, and does not increase morbidity rates.

Hunterian Lecture. Hernia surgery: from guidelines to clinical practice

INTRODUCTION

Over the last 30 years, hernia surgery has developed into an evidence-based practice assisted by the development of guidelines.

MATERIALS AND METHODS

Prior to 1993, best practice in the UK was a nylon darn repair under general anaesthesia as an inpatient with prolonged recovery. The publication of The Royal College of Surgeons of England (RCSE) Guidelines on Groin Hernia Repair stimulated debate and coincided with the introduction of mesh hernioplasty and laparoscopic techniques. Further evolution of hernia management has occurred to enable the production of the European Hernia Society (EHS) guidelines in 2008.

RESULTS

The EHS guidelines cover all aspects of abdominal wall surgery including: indications for operation; investigations; organising surgical care; techniques; local anaesthesia; after-care, complications and outcome; and information for patients.

CONCLUSIONS

Surgeons have many choices when selecting an appropriate hernia operation for an individual patient. The EHS guidelines provide a basis for this decision-making.

Low recurrence rate of a two-layered closure repair for primary and recurrent midline incisional hernia without mesh

Background

Incisional hernia is a serious complication after abdominal surgery and occurs in 11–23% of laparotomies. Repair can be done, for instance, with a direct suture technique, but recurrence rates are high. Recent literature advises the use of mesh repair. In contrast to this development, we studied the use of a direct suture repair in a separate layer technique. The objective of this retrospective observational study is to assess the outcomes (recurrences and complications) of a two-layered open closure repair for primary and recurrent midline incisional hernia without the use of mesh.

Methods

In an observational retrospective cohort study, we analysed the hospital and outpatient records of 77 consecutive patients who underwent surgery for a primary or recurrent incisional hernia between 1st May 2002 and 8th November 2006. The repair consisted of separate continuous suturing of the anterior and posterior fascia, including the rectus muscle, after extensive intra-abdominal adhesiolysis.

Results

Forty-one men (53.2%) and 36 women (46.8%) underwent surgery. Sixty-three operations (81.8%) were primary repairs and 14 (18.2%) were repairs for a recurrent incisional hernia. Of the 66 patients, on physical examination, three had a recurrence (4.5%) after an average follow-up of 2.6 years. The 30-day postoperative mortality was 1.1%. Wound infection was seen in five patients (6.5%).

Conclusions

A two-layered suture repair for primary and recurrent incisional hernia repair without mesh with extensive adhesiolysis was associated with a recurrence rate comparable to mesh repair and had an acceptable complication rate.

The role of suture fixation on mesh contraction after abdominal hernia repair

Mesh contraction is a threat for hernia repair. Our aim is to analyze the effects of fixation techniques on mesh contraction. Forty-eight rats with abdominal wall defects were equally divided into four groups (G): G1 (control) with no repair, G2 defects were repaired with free polypropylene mesh, and G3 and G4 defects were reinforced with prolene mesh fixed by running and interrupted sutures, respectively. The corners of the defect and prolene mesh were marked with silver clips. The contraction rate was calculated by radiological measurement of distances between corner clips and by measuring the mesh areas after harvesting abdominal wall containing the patch. Host reaction was histhopathologically and biochemically examined by inflammation score, fibroblast count, thickness of the granulation tissue, and tissue hydroxyproline level. Distances between corner clips and mesh area have decreased by 31.5% and 26.4% respectively in G2, while in G3 the decrease was 24.4% (p = .008) and 22% (p = .01), respectively. Granulation tissue thickness was highest in the group with mesh fixed by running suture. The tissue hydroxyproline levels were similar in mesh repair groups. Our study suggests that mesh contraction, which reduces mesh surface, occurs during the wound healing process. In order to decrease the contraction rate, it is important to keep the mesh in place until its incorporation into the surrounding tissue. Our results suggest that mesh contraction is minimized by suture fixation, and running fixation suture, which provides more balanced tension around the mesh, seems more beneficial for decreasing contraction rate.

Experimental study of the impact of the textile structure of mesh endoprostheses for the efficiency of reconstruction of the anterior abdominal wall

Endoprostheses made from knitted fabric of 3 loop types were used for hernioplasty in rats. Biocompatibility of implanted textile constructions was evaluated after 6 months. The intensity of inflammatory reaction and types of complications in animals depended on the loop type and method of finishing of the mesh endoprosthesis tissue.

Comparing quality-of-life outcomes in symptomatic patients undergoing laparoscopic or open ventral hernia repair

BACKGROUND

The aim of this study was to compare quality-of-life outcomes in patients with symptomatic hernias who were undergoing laparoscopic and open repairs.

MATERIALS AND METHODS

Clinical data for patients undergoing ventral hernia repair were reviewed with quality-of-life surveys administered before and at least 6 months following surgery.

RESULTS

The study included 56 symptomatic patients. Forty-one patients (73%) underwent laparoscopic repair, and 15 patients (27%) underwent open repair. There was no difference in preoperative quality-of-life scores on the SF-36 Health Survey between patients having laparoscopic or open repairs. Postoperative quality-of-life scores on the SF-36 survey were significantly improved in the laparoscopic group, compared with the open group, in general health (46% vs. 37%; P=0.0217), vitality (53% vs. 45%; P=0.0491), role-emotional (45% vs. 35%; P=0.0480), and mental health (49% vs. 39%; P=0.0381). Postoperative quality-of-life scores on the Carolinas Comfort Scale (CCS) were significantly improved in the laparoscopic group, compared with the open group, in bending over (3.15 vs. 5.87, P=0.0158), sitting up (2.51 vs. 5.13; P=0.0211), activities of daily living (2.48 vs. 5.75; P=0.0139), coughing or deep breathing (2.95 vs. 5.75; P=0.0314), walking (2.36 vs. 4.62; P=0.0427), exercising (3.19 vs. 6.14; P=0.0222), and total comfort scale (17.62 vs. 40.23; P=0.0084).

CONCLUSIONS

Laparoscopic ventral hernia repair provides improved quality-of-life, compared with open repair, 6 months postoperatively. Nearly all physical variables measured by the CCS were significantly better when ventral hernias were repaired laparoscopically.

Hernia recurrence after laparotomy: how to close an incised light-weight mesh?

A rising number of patients require relaparotomy after implantation of mesh materials for incisional hernia (IH) repair. No published recommendation concerning how to close the incision in a surgical mesh exists. We describe a central IH recurrence through a partly absorbable mesh positioned in the retromuscular plane 16 months after laparotomy due to a small bowel ileus. This recurrence was repaired using a heavy-weight, monofilament polypropylene mesh, again in the retromuscular position. Reducing the amount of nonabsorbable material in large pore hernia meshes leads to markedly reduced scar formation rather than the formation of a thick scar plate. Once cut and resutured, this scar may be too weak to withstand the mechanical strain, giving rise to a 'blow-out' IH recurrence, as demonstrated in our case. In these cases, re-enforcement with a nonabsorbable, small, porous polypropylene mesh in the retromuscular space is feasible and leads to the development of a mechanically stable scar.

Randomized clinical trial of groin hernia repair with titanium-coated lightweight mesh compared with standard polypropylene mesh

BACKGROUND

Groin hernia repair is one of the commonest operations in general surgery. Existing techniques have very low and acceptable recurrence rates, but chronic pain and discomfort remain a problem for many patients. New mesh materials are being developed to increase biocompatibility, and the aim of this study was to compare a new titanium-coated lightweight mesh with a standard polypropylene mesh.

METHODS

A randomized controlled single-centre clinical trial was designed, with the basic principle of one unit, one surgeon, one technique (Lichtenstein under general anaesthesia) and two meshes. Pain before and after surgery, and during convalescence (primary outcomes) was estimated in 317 patients. At 1-year clinical follow-up, recurrence, pain, discomfort and quality of life (secondary outcomes) were evaluated.

RESULTS

Patients with the lightweight mesh returned to work after 4 days, compared with 6.5 days for the standard mesh (P = 0.040). The lightweight group returned to normal activity after 7 days, versus 10 days for the standard group (P = 0.005). There was no difference in postoperative pain or recurrence at the 1-year follow-up.

CONCLUSION

Patients with the lightweight mesh had a shorter convalescence than those with the standard heavyweight mesh.

REGISTRATION NUMBER

ISRCTN36979348 (http://www.controlled-trials.com).

Open surgical procedures for incisional hernias

BACKGROUND

Incisional hernias occur frequently after abdominal surgery and can cause serious complications. The choice of a type of open operative repair is controversial. Determining the type of open operative repair is controversial, as the recurrence rate may be as high as 54%.

OBJECTIVES

To identify the best available open operative techniques for incisional hernias.

SEARCH STRATEGY

Electronic databases MEDLINE, EMBASE, LILACS, and the Cochrane Central Register of Controlled Trials (CENTRAL) were searched from 1990 to 2007 and trials were identified from the known trial reference lists.

SELECTION CRITERIA

Studies were eligible for inclusion if they were randomized trials comparing different techniques for open operative techniques for incisional hernias.

DATA COLLECTION AND ANALYSIS

Statistical analyses were performed using the fixed effects model. Results were expressed as relative risk for dichotomous outcomes and weighted mean difference for continuous outcomes with 95% confidence intervals.

MAIN RESULTS

Eight trials comparing different open repairs for incisional hernias were identified; one trial was excluded. The included studies enrolled 1,141 patients. The results of three trials comparing suture repair versus mesh repair were pooled. Hernia recurrence was more frequent, wound infection less frequent in the direct suture group compared to the onlay or sublay mesh groups. The recurrence rates of two trials comparing onlay and sublay positions were pooled. This comparison yielded no difference in recurrences (two studies pooled), although operation time was shorter in the onlay group (one study). No difference was found in recurrence, satisfaction with cosmetics, or infection between the onlay standard mesh and skin autograft groups, following analysis pooling the two treatment arms. However, the analysis demonstrated less pain in the skin autograft group. Other trials comparing different mesh materials or different positions of the mesh, or comparing mesh with the components separation technique are described individually. The comparison between lightweight and standard mesh showed a trend for more recurrences in the lightweight group. The comparison between onlay and intraperitoneal mesh positions resulted in non significant fewer hernia recurrences, less seroma formation and more postoperative pain in the intraperitoneal group. No differences in the recurrence rates between the components separation and the intraperitoneal mesh technique.

AUTHORS' CONCLUSIONS

There is good evidence from three trials that open mesh repair is superior to suture repair in terms of recurrences, but inferior when considering wound infection. Six trials yielded insufficient evidence as to which type of mesh or which mesh position (on- or sublay) should be used. There was also insufficient evidence to advocate the use of the components separation technique.

Prosthetic material in ventral hernia repair: how do I choose?

Several factors must be considered in deciding which mesh to use for a ventral hernia repair. Open hernia repairs with no exposure of mesh to viscera can be performed with unprotected synthetic mesh, preferably a "lightweight" option. For open repair with high risk for fascial dehiscence and visceral exposure to mesh, and for open underlay repair and laparoscopic underlay repair, recommendations call for a tissue-separating mesh that prevents ingrowth of intra-abdominal contents into the mesh. Although no long-term data are available about biologic (acellular collagen scaffold) meshes, these may have good results when used in contaminated or well-drained infected fields, and do best when used according to the principles of a high-quality synthetic mesh repair (wide mesh overlap, frequent fixation points). Evidence is still insufficient to support the use of biologic materials for primary hernia repair.

The repair of incisional hernia following Roux-en-Y gastric bypass-with or without concomitant abdominoplasty?

BACKGROUND

Incisional hernia, found in up to 25% of patients, is a typical complication of open bariatric surgery.

METHODS

Open Roux-en-Y gastric bypass (RYGB) was performed in 204 patients. They have been followed-up for at least 6 months. Thirty-two patients in whom incisional hernia was diagnosed were divided into two groups-they were scheduled for hernia repair or hernia repair with abdominoplasty. The surgery was performed, on average, 20 months after RYGB operation. Fourteen patients [mean body mass 86.4 kg, mean body mass index (BMI) 30.0 kg/m(2)] have had hernias repaired. The mean duration of hospital stay was 7.2 days. Hernia repair along with abdominoplasty was performed in 18 patients with mean body mass 89.4 kg and BMI 31.5 kg/m(2). The mean duration of hospital stay was 8.7 days.

RESULTS

Both examined groups were similar in body mass, BMI, age, and duration of hospital stay (p > 0.05), as well as gender distribution. The wound infection was diagnosed in six patients.

CONCLUSION

The simultaneous abdominoplasty does not prolong the time of hospital stay of the patients undergoing incisional hernia repair. Infection is the most frequent complication of incisional hernia repair.

Open onlay mesh repair for major abdominal wall hernias with selective use of components separation and fibrin sealant

BACKGROUND

The objective of the study was to reassess the efficacy of the open onlay technique for repair of major incisional hernias, utilizing the modern adjuncts of components separation and fibrin sealant to reduce the principal complications of seroma and recurrence. Major incisional hernias were defined as >10 cm transverse diameter.

METHODS

A prospective audit was applied to 116 patients undergoing open onlay incisional hernia repair during a 2-year period at a single institution. Information was collected concerning operative details, postoperative complications, and recurrence. Clinical review at a median 15.2 months postoperatively was followed by a telephoned structured questionnaire to assess quality of life. All patients with pain or suspected recurrence were recalled for examination.

RESULTS

Fascial closure required components separation in 21 (18.1%) patients when tension-free fascia reconstruction was not possible, and fibrin sealant was applied in 22 (18.9%) in whom extensive skin flaps were dissected beyond the semilunar line. Postoperatively, there were 11 (9.5%) seromas and 2 (1.7%) deep wound infections. At 15.2 months' follow-up there were 4 (3.4%) recurrences.

CONCLUSIONS

Open onlay mesh repair for major incisional hernias is a versatile operation applicable to all quadrants of the abdominal wall and gives excellent results when used in association with components separation and fibrin sealant.

Biomechanical analyses of overlap and mesh dislocation in an incisional hernia model in vitro

BACKGROUND

Incisional hernia repair is one of the most common surgical complications. Despite the introduction of mesh techniques of repair, recurrences are still prevalent. The aim of the current study was to evaluate the dependence of mesh dislocation on defect size, facial overlap, mesh-position, and orientation of the mesh in cases of anisotropic stretchability.

METHODS

An in vitro incisional hernia model was used, which consisted of a pressure chamber, an elastic silicone pad representing the peritoneal sac, and a silicone mat with bovine muscle tissue representing the abdominal wall. Intrinsic pressure (up to 200 mm Hg) was generated within the pressure chamber by continuous inflation with CO(2). A slit-like or flap-like defect was created in the silicone mat to simulate small or large hernia defects, respectively. The implanted mesh was arranged in both onlay and sublay configurations. A large pore polypropylene mesh with significant anisotropic stretchability was investigated, whereas overlaps of 2, 3, and 4 cm were applied.

RESULTS

Despite the application of pressures up to 200 mm Hg, no mesh ruptures occurred. In the slit-like defect model, the minimal overlap required to prevent dislocation at 200 mm Hg was 3 cm using the sublay technique provided that the mesh was positioned with its most stretchable axis parallel to the largest slit dehiscence. Perpendicular rotation of the mesh resulted in dislocation at 160 mm Hg, despite using an overlap of 3 cm. Mesh reinforcement showed less stability in both the onlay position and the flap-like defect.

CONCLUSION

An overlap of 3 cm is sufficient to prevent early mesh dislocation. Meshes with anisotropic stretchability should be orientated with the most stretchable axis in the direction of least overlap.

Comparison of recurrence with lightweight composite polypropylene mesh and heavyweight mesh in laparoscopic totally extraperitoneal inguinal hernia repair: an audit of 1,232 repairs

BACKGROUND

In Edinburgh a group of surgeons agreed to convert to a lightweight, composite mesh (Ultrapro-Ethicon) for totally extraperitoneal (TEP) inguinal hernia surgery. The aim of this study was to compare the outcome following the use of a new lightweight vs a standard heavyweight mesh during TEP hernia repair.

METHODS

Patients undergoing TEP using lightweight (LWM) or heavyweight meshes (HWM) between March 2004 and March 2006 were identified from the Lothian Surgical Audit database. The patients who re-presented with recurrence of hernia were studied in greater detail. Date of re-attendance at a clinic with recurrence was used as a surrogate for date of recurrence.

RESULTS

Two hundred and fifty one patients had 371 hernia repairs with LWM. A total of 16 (4.3%) recurred with a median follow-up of 14.5 months. A concurrent group of 326 patients had 425 repairs with standard mesh and have had 12 (2.82%) recurrences with a median follow-up of 22.4 months. A group of patients operated immediately prior to the introduction of LWM consisted of 328 patients who had 436 repairs using HWM, of whom 13 (2.98%) have recurred with a median follow-up of 43 months. Whilst there are no statistically significant differences in recurrence rates between these groups, we are concerned that the LWM group has the highest recurrence rate despite the shortest follow-up.

CONCLUSION

In view of increased patient comfort, we continue to recommend LWM for laparoscopic inguinal hernia surgery but would recommend that, in larger hernias and possibly for all, the surgeon should improve mesh adhesion.

Mesh migration into the esophageal wall after mesh hiatoplasty: comparison of two alloplastic materials

BACKGROUND

Hiatal mesh implantation in the operative treatment of gastroesophageal reflux disease has become an increasing therapy option. Besides clinical results little is known about histological changes in the esophageal wall.

METHODS

Two different meshes [polypropylene (PP), Prolene; polypropylene-polyglecaprone 25 composite (PP-PG), Ultrapro] were placed on the diaphragm circular the esophagus of 20 female rabbits. After three months a swallow with iodine water-soluble contrast medium for functional analysis was performed. After the animals were sacrificed, histopathological evaluation of the foreign-body reaction, the localization of the mesh relating to the esophageal wall was analyzed.

RESULTS

Sixteen rabbits survived the complete observation period of three months. After three months distinctive mesh shrinkage was observed in all animals and meshes had lost up to 50% of their original size before implantation. We found a delayed passage of the fluid into the stomach in all operated animals. There was a significant increased diameter of the outer ring of granulomas in the PP group (76.5 +/- 8.0) compared to the PP-PG group (64 +/- 8.5; p = 0.002). However, we found a mesh migration into the esophageal wall in six out of seven animals (PP) and five out of nine animals (PP-PG), respectively.

CONCLUSION

Experimental data suggest that more knowledge is necessary to assess the optimal size, structure, and position of prosthetic materials for mesh hiatoplasty. The indication for mesh implantation in the hiatal region should be carried out very carefully.

Repair of large complex recurrent incisional hernias with retromuscular mesh and panniculectomy

BACKGROUND

Recurrent incisional hernia repair is associated with high recurrence and wound complication rates.

METHODS

The clinical courses of patients who underwent recurrent incisional hernia repair via retromuscular mesh placement with concomitant panniculectomy at a university teaching hospital from 1999 to 2004 were reviewed retrospectively. Postoperative evaluation included a quality of life survey.

RESULTS

Forty-seven patients (13 male, 34 female) with an average body mass index of 34.4 kg/m2, an average midline hernia defect of 31.4 cm, and at least 1 and on average 2.5 previous repair attempts underwent hernia repair. Wound infections occurred in 4 patients (8%) and seromas requiring aspiration occurred in 1 patient (2%). Four patients (8%) had re-recurrences of their hernias. All patients rated the postoperative appearance of their abdomen as at least satisfactory.

CONCLUSIONS

Recurrent incisional hernia repair with a retromuscular mesh and panniculectomy has low recurrence and wound complication rates and excellent patient satisfaction.

Are mesh anchoring sutures necessary in ventral hernioplasty? Multicenter study

BACKGROUND

Avoiding mesh fixation to the surrounding tissue in ventral hernioplasty would simplify the operation, decrease the time of the procedure, and decrease the risk of suture-related complications.

METHODS

Four hospitals included 111 patients according to the common protocol for prospective clinical evaluation of sutureless ventral hernioplasty. Surgical technique involves placement of the polypropylene mesh with flat-shape memory in either the retromuscular or preperitoneal space without suture anchoring.

RESULTS

Local complication rate was low (12.6%, 14 patients), postoperative pain measured according to the visual analogue scale was minimal (mean 4, range 1-8). Three recurrences (3%) were recorded. Mild scar discomfort, which did not require treatment nor limit physical activity, was recorded in 28 (25%), 18 (17%), and 11 (14%) patients at 6-month, 1- and 2-year follow-up, respectively.

CONCLUSIONS

Results of the study suggest that the sutureless sublay technique is safe and effective in the treatment of ventral abdominal hernia, especially in small and medium defects.

Sterilized Mosquito Net versus Commercial Mesh for Hernia Repair

BACKGROUND

In industrialized countries alloplastic meshes are routinely used for hernia repair. However, in developing countries they are rarely available or affordable. This study compares textile properties and tissue response of commercial polypropylene mesh (PM) vs. sterilized nylon mosquito net (MN).

METHODS

Textile properties were examined in vitro. In 12 goats one MN and one PM (5.5 x 8 cm) were implanted onto the posterior layer of the rectus sheath. Wound healing was clinically assessed. Histology was assessed after 4 or 16 weeks.

RESULTS

MN was thinner and lighter, but weaker than PM. All wounds healed without complications. After 16 weeks foreign body granulomas in the MN group contained a higher proportion of inflammatory tissue (32.7 vs. 22.1%) and more giant cells (3.1 vs. 1.7/10 granulomas) with a significantly lower partial volume of foreign body (23.2 vs. 36.9%). Partial volume of fibrotic tissue was similar. MN was 1,000-fold cheaper than PM.

CONCLUSIONS

PM was superior concerning strength and extent of inflammatory response. However, the findings indicate that MN might serve as a cheap substitute if an alloplastic mesh is needed but no commercial one is available or affordable. Further studies are justified which should include mosquito nets of different materials and long-term outcome.

Operative treatment of ventral hernia using prosthetic materials

OBJECTIVE

The objective of this study was to summarize the clinical experiences in repairing abdominal incisional hernia with prosthetic materials.

METHODS

Eighty-three patients with ventral hernia were analyzed retrospectively.

RESULTS

Two patients developed pulmonary infection, one developed adhesive ileus, and five developed wound infection. All wounds healed completely during follow-up. Seventy-three (88%) patients were free of pain, and ten patients (12%) felt pain in the operated area within the last month; only one patient required pain-relieving drugs. Twenty-nine patients (35%) felt discomfort, such as stiffness. Four cases experienced postoperative recurrence.

CONCLUSIONS

Incisional herniorrhaphy with prosthetic materials is safe and effective but has a high discomfort rate. Open giant incisional hernia or recurrent incisional hernia should be performed by trained surgeons. Placing mesh in a suitable position and using a patch with minimal reaction and enough tensile strength may improve the prognosis. Further studies are necessary utilizing light polypropylene mesh.

Autologous tissue repair of large abdominal wall defects

Background and method

Techniques for autologous repair of abdominal wall defects that could not be closed primarily are reviewed. Medline and PubMed were searched for English or German publications using the following keywords: components separation technique (CST), Ramirez, da Silva, fascia lata, tensor fasciae latae, latissimus dorsi, rectus femoris, myocutaneous flap, ((auto)dermal) graft, dermoplasty, cutisplasty, hernia, abdominal wall defect, or combinations thereof. Publications were analysed for methodological quality, and data on surgical technique, mortality, morbidity and reherniation were abstracted.

Results and conclusions

The CST is the best documented procedure; it is associated with a high morbidity rate of 24·0 per cent and a recurrence rate of 18·2 per cent. Although the results of the da Silva technique are good (morbidity 5–20 per cent and reherniation 0–3 per cent), the poor methodological quality of the studies precludes firm conclusions. Repair with free fascia lata or dermal grafts is an alternative if the above techniques cannot be used, but wound complications affect 42 per cent of patients and recurrent hernia up to 29 per cent. Pedicled or free vascularized flaps are reserved for complex situations.

Interposition of Polyglactin Mesh Does Not Prevent Adhesion Formation Between Viscera and Polypropylene Mesh

BACKGROUND

The use of intra-peritoneal polypropylene mesh (PPM) to repair incisional hernia carries the risk of adhesions and damage to the intra-abdominal viscera. Polyglactin 910 mesh (PGM) is advocated to avoid contact between PPM and the intra-abdominal viscera. An experimental study in rats was performed to determine if interposition of a resorbable prosthesis between the PPM and viscera alters biocompatibility, adhesion formation, and herniation.

MATERIALS AND METHODS

A 2- x 3-cm abdominal wall defect was created in 80 rats. Rats were randomly assigned for repair with 2.5- x 3.5-cm PPM (n = 40) or 2.5- x 3.5-cm PPM plus polyglactin 910 mesh (PPM-PGM) (n = 40). The rats were sacrificed at 1, 2, 3, and 6 months (n = 10), and an autopsy was performed to determine herniation and adhesion rates. Mesh-fascia interface was taken for histology.

RESULTS

In the PPM group, 1 rat died before the end of the experiment, and at 6 months one of the 10 rats had a herniation. In the PPM-PGM group, two rats died before the end of the experiment, and two rats had a herniation after 1 month and three rats after 6 months. At 1, 2, and 3 months the adhesion score in the PPM group (median, 3; range, 2-3) did not differ from the score in the PPM-PGM group (median, 3; range, 2-3). Also, at 6 months the adhesion score in the PPM group (median, 2; range, 2-3) did not differ from the score in the PPM-PGM group (median, 3; range, 2-3). At microscopy a capsule was formed around the PP fibers, which matured over months in the PPM group. In the first month after implantation an inflammatory response was seen. Histology was similar in both groups, although in the early PPM-PGM group the inflammatory response was more evident.

CONCLUSION

Interposition of PGM between PPM and viscera does not alter adhesion formation nor influences herniation rate.

The analysis of infection after polypropylene mesh repair of abdominal wall hernia

AIM

The aim of the study was to evaluate the frequency of superficial and prosthetic mesh infection following polypropylene mesh repair of different abdominal wall hernia in individual patients and to analyze the manifestation, clinical process and outcomes in patients with prosthetic mesh infection.

METHODS

This was a retrospective analysis of 375 patients with 423 implanted meshes for groin, femoral, umbilical, incisional and epigastric hernias, with a mean follow-up of 15 months (range: 3-73 months).

RESULTS

The total superficial infection rate was 1.65%, and the rate of mesh infection was 0.94%. There were no statistically significant differences in prosthetic mesh infection between monofilament and multifilament meshes as well as between the different repair groups of hernias. The deep incisional surgical site infection after previous operation was established as a significant risk factor for prosthetic mesh infection in incisional hernia repair (P < 0.0001). Five cases of prosthetic mesh infection were presented and analyzed.

CONCLUSIONS

There is no correlation between the superficial and prosthetic mesh infection. There may be difficulties in determining mesh infection and to choose the right tactic. The reconvalescence in all patients with mesh infection was achieved only after removal of the infected mesh.

Improving outcomes in hernia repair by the use of light meshes--a comparison of different implant constructions based on a critical appraisal of the literature

BACKGROUND

Despite convincing advantages offered by meshes, their use in hernia surgery remains controversial because of fears concerning the long-term effects of their implantation. To improve biocompatibility, a large variety of newly developed light meshes has been introduced to the market. This overview of the literature aimed to establish whether absolute material reduction (g per implanted mesh), use of absorbable components, and coating by inert materials are evidence-based ways to improve biocompatibility of meshes.

METHOD

A review of the current English and German language literature on the outcome of groin und incisional hernia mesh repair was performed. Both basic research and clinical trials were used as sources of data. Meta-analyses and randomized controlled trials were given priority and were referred to whenever possible.

RESULTS

Operative technique was an independent prognostic factor for the clinical outcome. Mesh construction and composition as characterized by pore size and filament structure appeared to be more important determinants of foreign body reaction after implantation than absolute material reduction of 1 g or more per implant. No data exist about an oncogenic effect of alloplastic materials in humans, but disturbed fertility in animal studies remains an issue of concern and should be further investigated.

CONCLUSIONS

According to data from current randomized controlled trials and retrospective studies, light meshes seem to have some advantages with respect to postoperative pain and foreign body sensation. However, their use is associated with increased recurrence rates. Light meshes offer no advantages with respect to alleviating severe chronic groin pain. At the same time, experimental data reveal that material composition and mesh structure may significantly affect foreign body reaction.

Inguinal hernia repair: the choice of prosthesis outweighs that of technique

BACKGROUND

The use of prostheses in inguinal hernia repair reduces the incidence of recurrence. Quality of life and pain after hernia repair are largely correlated with the technique and type of prosthesis.

AIMS OF STUDY

To evaluate the 2-year incidence of recurrence and pain for two types of hernioplasty, Lichtenstein repair and laparoscopy (totally extraperitoneal approach or TEP), and two types of mesh, polypropylene mesh and beta-D: -glucan-coated mesh (Glucamesh).

PATIENTS

A total of 410 consecutive patients of mean age 54 years (18-84) underwent repair of inguinal hernias, 96 (23%) of which were bilateral and 56 (13%) recurrent. A total of 273 (66.5%) patients underwent Lichtenstein repair: 215 (78.7%) with polypropylene mesh, 58 (21.3%) with Glucamesh; 137 patients underwent laparoscopy: 80 (58.4%) with polypropylene mesh, 57 (41.6%) with Glucamesh. In each group, the populations were comparable and the techniques utilized were identical.

METHODS

The patients were followed-up for at least 2 years, after which the incidence of recurrence was determined, and chronic pain was assessed by means of a visual analog scale and a validated questionnaire.

RESULTS

A total of 349 patients (85.1%) were reassessed, 117 of whom had undergone laparoscopy and 232 Lichtenstein repair. There were ten recurrences (2.8%), and incidence which was independent of the technique (laparoscopy 1.7% vs. Lichtenstein 3.4%) (ns) and the type of prosthesis (Glucamesh 1.9% vs. polypropylene 2.4%) (ns). Chronic pain was noted in 69 patients (19.7%) and severe pain in 11 (3.1%). The incidence of chronic pain was the same for the two techniques: laparoscopy 17.9% vs. Lichtenstein 20.7% (ns). The same was true for severe pain: laparoscopy 3.4% vs Lichtenstein 3% (ns). The incidence of chronic pain was closely correlated with the type of prosthesis utilized: Glucamesh 4.8% vs. polypropylene 26.5% (P = 0.02), irrespective of the technique. The same was true for severe pain (0.9 vs. 4%) (P = 0.02).

CONCLUSION

The utilization of beta-D: -glucan-coated mesh did not involve more recurrence and was accompanied by a significant decrease in chronic pain at 2 years, independent of the technique. After 2 years, the results of hernia repair show that the choice of prosthesis was more determinant than choice of technique.