Joachim Conze

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

Polymer mesh has been used to repair incisional hernias with lower recurrence rates than suture repair. A new generation of mesh has been developed with reduced polypropylene mass and increased pore size. The aim of this study was to compare standard mesh with new lightweight mesh in patients undergoing incisional hernia repair.

DIE PRAPERITONEALE NETZPLASTIK IN DER REPARATION DER NARBENHERNIE : EINE VERGLEICHENDE RETROSPEKTIVE STUDIE AN 272 OPERIERTEN NARBENHERNIEN

Summary. In a retrospective study on 245 patients we evaluated the results of 272 incisional hernia repairs in the Department Surgery of the University Hospital Aachen. The group consisted of 58 % male and 42 % female patients with a mean age of 61.1 years and 111 primary and 161 recurrent incisional hernias. Conventional techniques (simple closure, Mayo) and alloplastic repairs were performed in 69.9 and 30.1 %, respectively. During the last 4 years we predominantly used the preperitoneal mesh repair with polypropylene mesh (Marlex®). The results of 87 % of our group of patients were evaluated by questionnaire and information from the family physicians (mean follow-up period 64 months). The patients who underwent preperitoneal mesh repair were examined clinically and with ultrasound. In comparison to the results of conventional hernia repair, early complications (seroma, hematoma) were higher. The recurrence rate, however, was significantly lower in this group with mesh repair (6.8 %) than in patients without alloplastic augmentation (32.6 %). Whereas preperitoneal mesh repair is convincingly the ideal surgical technique, optimization of the alloplastic materials by reduction of the amount of foreign substance and improvement of elasticity and biocompatibility is mandatory.Zusammenfassung. In einer retrospektiven Studie an 245 Patienten mit 272 Narbenhernien wurden die Ergebnisse der Narbenhernienoperationen an der Chirurgischen Universitätsklinik Aachen von 1987 bis 1994 untersucht. Dabei handelte es sich um 111 Primär- und 161 Rezidiv-Narbenhernien, 58 % Männer und 42 % Frauen, mit einem Altersdurchschnitt von 61,1 Jahren. An operativen Verfahren kamen bei 69,9 % der Patienten konventionelle Verfahren (Stoß auf Stoß, Mayo) und bei 30,1 % der Fälle eine Reparation mit alloplastischen Materialien zur Anwendung. Dabei verwendeten wir in den letzten 4 Jahren vornehmlich die präperitoneale Netzplastik (PNP) mit einem Polypropylen-Netz (Marlex®). Mittels Fragebogen und Befragung der Hausärzte konnten die Ergebnisse von 87 % der Patienten erfaßt werden (durchschnittlicher Nachbeobachtungszeitraum 64 Monate). Die Patienten mit PNP wurden klinisch und sonographisch nachuntersucht. Der Vergleich der PNP-Patienten mit den konventionellen Verfahren, zeigte eine erhöhte Rate von Frühkomplikationen (Serome, Hämatome), die Rezidivrate war mit 6,8 % jedoch signifikant niedriger als bei den Reparationen ohne alloplastische Materialien (32,6 %). Während die PNP als Operationstechnik als ideales Verfahren überzeugt, scheint eine Optimierung der verwendeten alloplastischen Materialien, mit Reduktion des Fremdmaterials, vermehrter Elastizität und verbesserter Biokompatibilität notwendig.

Incisional Hernia: Open Techniques

Even with the routine use of mesh, repairing an incisional hernia is a challenge. Increasing evidence of impaired wound healing in these patients supports routine use of an open prefascial, retromuscular mesh repair. Basic pathophysiologic principles dictate that for a successful long-term outcome and prevention of recurrence a wide overlap underneath healthy tissue is required. The extent of this overlap should be 5 cm in all directions: surrounding the wound closure, subxiphoidal underneath the ribs, below the arcuate line, and retropubic.

Criteria for definition of a complex abdominal wall hernia

AbstractPurpose A clear definition of “complex (abdominal wall) hernia” is missing, though the term is often used. Practically all “complex hernia” literature is retrospective and lacks proper description of the population. There is need for clarification and classification to improve patient care and allow comparison of different surgical approaches. The aim of this study was to reach consensus on criteria used to define a patient with “complex” hernia.MethodsThree consensus meetings were convened by surgeons with expertise in complex abdominal wall hernias, aimed at laying down criteria that can be used to define “complex hernia” patients, and to divide patients in severity classes. To aid discussion, literature review was performed to identify hernia classification systems, and to find evidence for patient and hernia variables that influence treatment and/or prognosis.ResultsConsensus was reached on 22 patient and hernia variables for “complex” hernia criteria inclusion which were grouped under four categories: “Size and location”, “Contamination/soft tissue condition”, “Patient history/risk factors”, and “Clinical scenario”. These variables were further divided in three patient severity classes (‘Minor’, ‘Moderate’, and ‘Major’) to provide guidance for peri-operative planning and measures, the risk of a complicated post-operative course, and the extent of financial costs associated with treatment of these hernia patients.ConclusionCommon criteria that can be used in defining and describing “complex” (abdominal wall) hernia patients have been identified and divided under four categories and three severity classes. Next step would be to create and validate treatment algorithms to guide the choice of surgical technique including mesh type for the various complex hernias.

New polymer for intra‐abdominal meshes—PVDF copolymer

PURPOSE Full tissue integration without adhesion formation is still a challenge for intra-abdominal mesh materials. Purpose of this study was to investigate the adhesive potential and fibrocollagenous ingrowth of a polymer blend of polyvinylidene fluoride and hexafluorpropylene (co-PVDF), an established suture material in vascular surgery, when placed as a mesh in the intra-abdominal position. The results were compared with a matching polypropylene (PP) mesh. METHODS In an established rabbit model, mesh implantation was performed by laparoscopy in the intraperitoneal onlay mesh technique. After 7, 21, and 90 days the degree of adhesion formation, foreign body reaction, bridging, and shrinkage of mesh area were investigated. RESULTS In the early phase after 7 and 21 days we found significantly more adhesions for PP, but no differences after 90 days. Analysis of tissue reaction showed a significantly lower fibrotic reaction for co-PVDF. The degree of shrinkage revealed no significant difference. CONCLUSION Large-pore PP and co-PVDF-meshes showed comparable good results in the intra-abdominal position, with a reduced inflammatory tissue reaction for co-PVDF. Large pore meshes should be considered an alternative for the development of intraperitoneal onlay meshes.

The Pfannenstiel or so called “bikini cut”: Still effective more than 100 years after first description

The original Pfannenstiel incision is discussed including the technique, history, current indications, advantages, and disadvantages. Excellent cosmetic results, principles of less traumatic surgery, and a rare incisional hernia complication rate of about 0–2%, as well as long-time use characterise this access path to the pelvic organs first described by the German gynaecologist in 1900. Complications of nerve damage, however, should be recognised, especially when extending the incision too far laterally.

Abdominal wall compliance after Marlex® mesh implantation for incisional hernia repair

SummaryIn view of the poor results of suturing techniques, incisional hernias are often best repaired with biomaterials. Their use brings the recurrence rate to below 10%, but patients sometimes complain of discomfort and restricted abdominal mobility. We report our experience with 41 patients after implantation of a Marlex®-mesh in a preperitoneal, retromuscular position (mean follow-up period 16.7 months). The effect of implanted meshes on abdominal wall mobility was measured noninvasively with the aid of three dimensional stereography and compared with a non-operated healthy control group (n = 21). The commonest early postoperative complication was seroma in 32% of cases, usually relieved by aspiration. Infection and hematoma were less frequent at 4.9% and 12.2% respectively. Three patients developed a recurrent hernia. During follow-up 7.3% experienced pain during heavy activities, 29.3% during daily activities and 4.9% at rest. Three dimensional stereography showed a highly significant (p < 0.001) decrease in abdominal wall mobility following mesh implantation, compared to a non-operated control group. Improved composition of the mesh material involving a smaller proportion of polypropylene and greater elasticity, should be considered for the future, in order to reduce patient discomfort.

Incisional hernia: challenge of re-operations after mesh repair

Background and aimsThe widespread use of meshes for the repair of incisional hernia is currently followed by an increasing number of re-operations. The incidence of incisional hernia recurrence after mesh repair varies between 3 and 32%. The problem of mesh failure and options for another surgical intervention seem rather unattended.MethodsWe present our experience of 77 re-operations after previous mesh repair that were performed between 1995 and 2004 out of a total of 1,070 operations for incisional hernia. The retrospective analysis focused on recurrence in relation to location, material of the previous mesh repair and the surgical procedure to resolve the problem.ResultsThe locations of the preceding meshes were epifascial as onlays (n=23), retromuscular as sublays (n=46), within the defect as inlays (n=6) or intraperitoneally (n=2). The direction of the incision was vertical medial (n=41) or horizontal crossing the linea semilunaris (n=36). Recurrences after median incisional hernia mesh repair mainly occurred at the cranial border of the mesh subxiphoidal. Except for two patients, all recurrences manifested at the margin of the enclosed mesh.ConclusionsRe-operation after previous mesh repair is a surgical challenge. The type of revision procedure has to consider the position and material of the previous mesh. In our clinic recurrences, heavyweight polypropylene meshes were mostly treated with mesh exchange and lightweight polypropylene meshes could be treated by extension with a second mesh. In contrast to suture techniques, deficient mesh repairs are more evidently related to technical problems.

Vernderung der bauchwandmechanik nach mesh-implantation Experimentelle vernderung der mesh-stabilitt Alteration of abdominal wall mechanics after mesh implanation. Experimental alteration of mesh stability

The use of biomaterials for incisional hernia markedly reduces the recurrence rates. Disadvantages are high rates of local wound complications and restriction of mobility by the rigid “shell”. The abdominal wall mobility after mesh implantation is analysed for eight different mesh materials. The initial textile testing reveals relevant differences in structure with marked asymmetry in the different directions. The materials are implanted as inlay in rats for 3, 7, 14, 21 and 90 days. The deformation of the abdominal wall following intraabdominal pressure of 0–70 mmHg (0–9.81 kPa) is documented by 3D-photogrammetry, the tensile strength by tearing of excised strips of mesh. Three commercial available materials and two laboratory modifications lead independently of their textile characteristics to a marked restriction of the rounded configuration of the abdominal wall. The tensile strength exceeds by far the physiologically necessary value of 16 N/cm. Three newly developed meshes made of multifilament polypropylene with reduced amounts of material (21% and 28% relative to Marlex®) lead to no restriction of the abdominal wall configuration yet have uncompromised stability. It might be possible to reduce the rate of local wound complications by the use of these newly developed meshes.ZusammenfassungErst der Einsatz von Biomaterialien führt beim Verschluß von Narbenhernien zu akzeptablen Rezidivquoten. Dies wird erkauft durch eine hohe Rate lokaler Wundkomplikationen mit Ausbildung einer starren Narbenplatte. Acht verschiedene Mesh-Materialien wurden in ihren Auswirkungen auf die Bauchwandbeweglichkeit im Tierversuch analysiert. Hierzu wurden sie zunächst einer textiltechnischen Prüfung nach DIN unterzogen. Es zeigten sich deutliche Unterschiede in der Netzstruktur mit erheblicher Asymmetrie. Anschließend erfolgte die standardisierte Implantation als In-lay in Ratten für 3, 7, 14, 21 und 90 Tage. Die Veränderung der Bauchwandbeweglichkeit bei intraabdominaler Druckbelastung von 0–70 mmHg (0–9,81 kPa) wurde mittels 3-D-Photogrammetrie erfaßt. Die Prüfung der Reißfestigkeit erfolgte im Steifenzugversuch. Drei kommerziell erhältliche Materialien sowie 2 Labormodifikationen führten unabhängig von ihren textilen Eigenschaften zur deutlichen Einschränkung der Bauchwandkrümmung. Dabei lag die Reißfestigkeit sowohl bei der textiltechnischen Prüfung als auch im Streifenzugversuch nach Implantation weit über dem physiologisch erforderlichen Wert von 16 N/cm. Drei neu entwickelte Materialien aus multifilem Polypropylen mit reduziertem Materialanteil (21 und 28% im Vergleich zum Marlex®) führen bei erhaltener Stabilität zu keiner nachweisbaren Einschränkung der Bauchwandkrümmung. Möglicherweise läßt sich durch derartige neu entwickelte Netzmaterialien die Rate der lokalen Wundkomplikationen vermindern.

Biocompatibility of prosthetic meshes in abdominal surgery

Surgical meshes today represent a group of implants mainly used for hernia repair. Modern hernia surgery is no longer imaginable without the application of these special biomaterials leading to millions of implantations each year worldwide. Because clinical trials are insufficient to evaluate the distinct effects of modified mesh materials in regard to tissue biocompatibility and functionality, a basic understanding of the physicochemical properties of mesh materials, as well as the underlying cause for hernia formation, is essential for a rational selection of the most appropriate device. The most important properties of meshes were found to be the type of filament, tensile strength, and experimental data, which indicate that particularly the meshs porosity is of outstanding importance.