No abstract

Adverse events have been reported with acrylic bone cements. However, current test standards for acrylic materials fail to characterize the potentially harmful monomers released during the curing stage. In clinical applications, materials are implanted into the human body during this phase. Silicone may be a safer alternative to acrylic cements. Silicone is used in medical applications for its biocompatibility and stability characteristics. Previously, no study has been completed which compares silicone to acrylic cements. In this study, both materials were injected into the cell medium during the curing process which more accurately reflects clinical use of material. Initially, cell cultures followed ASTM standard F813-07 which fails to capture the effects of monomer released during curing. Subsequently, a modified cell culture method was employed which evaluated cytotoxicity while the materials cured. The objective of this study was to capture toxicity data during curing phase. Thus, the test method employed measured and excluded the impact of the exothermic reaction temperature of polymethyl methacrylate (PMMA) on cell growth. The concentration of PMMA monomer was measured at 1 and 24 h after injecting PMMA into culture plates in a manner consistent with established cell growth methodologies. Our results indicate current in vitro cytotoxicity assays recommended by ASTM standards are unable to reveal the real cytotoxic effect caused by methyl methacrylate monomers during polymerization. Our modified experiment can more accurately illustrate the true nature of the toxicity of materials and improve assay results. In these tests, silicone based elastomeric polymers showed excellent cytocompatibility. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 2693-2699, 2018.

An der I. Chirurgischen Klinik für Allgemein- und Thoraxchirurgie des Diakoniekrankenhauses Rotenburg (Wümme) wuden im Zeitraum vom Oktober 1992 bis Dezember 1995 1154 Hernien bei 997 Patienten mit der transabdominellen präperitonealen Patch-Plastik (TAPP) versorgt. 761 Patienten mit 895 Hernien (107 Rezidivhernien, nach konventioneller Voroperation) mit wenigstens 3 Monate zurückliegender Operation wurden retrospek-tiv analysiert. Im postoperativen Nachbeobachtungszeitraum von 3-35 Monaten kamen 10 Frührezidive zur Beobachtung, keines davon bei den laparoskopisch operierten Rezidivhernien. Implantatinfektionen oder -unverträglichkeiten wurden nicht beobachtet. Mögliche Vor- und Nachteile der konventionellen und der laparoskopischen Versorgung von Inguinalhernien werden diskutiert, und anhand vorliegender Schrifttumsangaben sowie der eigenen Leistungsdaten wird gefolgert, daβ die TAPP ein ausgereiftes und sicheres Operationsverfahren, insbesondere zur Versorgung von Rezidivleistenhernien, zu sein scheint.

Introduction Vertebral compression fractures (VCF) are an increasing problem. Common surgical treatments are vertebroplasty and kyphoplasty. Both are mainly performed with PMMA bone cement. Recently a new elastomer (VK100) was developed as optional material for kyphoplasty instead of PMMA. This study investigated the outcome and safety of balloon kyphoplasty performed with the VK100 Vertebral Augmentation System over a follow-up period of 12 months. Material and Methods The study includes patients with osteoporotic fractures of one or two vertebrae. All patients were treated with balloon kyphoplasty using VK100 (Bonwrx, Lansing, Michigan, USA) instead of PMMA. VK100 is a radio opaque, bone adherent, non-exotermic elastomer, which is less stiff as PMMA and therefore more comparable to the natural bone. VAS and ODI of all patients was measured preoperative, postoperative, at 12 months. Additional cement leakage and additional fractures were documented. Results 82 patients were included in the study (age: 63.69 ± 7.54). VAS improved significantly from preoperative 82.9 ± 10 mm to postoperative 18.3 ± 10.2 mm (p = 0.0015) and improved significantly from postoperative to 8.92 ± 11.5 mm at the 12 months follow up (p = 0.0163). ODI improved significantly from preoperative 72.92 ± 14.6% to postoperative 47.08 ± 16.35% (p = 0.0015) and from postoperative to 20.15 ± 7.56 at 12 months (p = 0.0022). There were no complications due to leakage. Patients showed no additional fractures within the follow up period. Conclusion VK100 showed good results in terms of VAS and ODI improvement and occurrence of adverse events. VK100 is an alternative to PMMA bone cement augmentation. Further studies are needed for longer implantation years.