Evidence of time dependent degradation of polypropylene surgical mesh explanted from the abdomen and vagina of sheep

The failure of polypropylene mesh is marked by significant side effects and debilitation, arising from a complex interplay of factors. One key contributor is the pronounced physico-mechanical mismatch between the polypropylene (PP) fibres and surrounding tissues, resulting in substantial physical damage, inflammation, and persistent pain. However, the primary cause of sustained inflammation due to polypropylene itself remains incompletely understood. This study comprises a comprehensive, multi-pronged investigation to unravel the effects of implantation on a presumed inert PP mesh in sheep. Employing both advanced and conventional techniques to discern the physical and chemical transformations of the implanted PP. Our analyses reveal a surface degradation and oxidation of polypropylene fibres after 60 days implantation, persisting and intensifying at the 180-day mark. The emergence and accumulation of PP debris in the tissue surrounding the implant also increased with implantation time. We demonstrate observable physical and mechanical alterations in the fibre surface and stiffness. Our study shows surface alterations which indicate that PP is evidently less chemically inert than was initially presumed. These findings underscore the need for a re-evaluation of the biocompatibility and long-term consequences of using PP mesh implants.