Professor University of Tennessee Knoxville, United States
Infection is a major complication of implanted orthopedic devices (Lozano, 2021). Effective sterilization of a device is one essential part of reducing the risk of infection. There are several methods for sterilization, and all may not be appropriate for all devices. For heat-tolerant materials, steam sterilization is considered the most dependable sterilization method (CDC, 2008). A low-temperature alternative, vaporized hydrogen peroxide (VH2O2), is compatible with most materials but may not penetrate through materials as well. Our lab is testing prototypes of a novel jointed foot-ankle endoprosthesis consisting of a stainless-steel core, a silicone coating, and polyethylene-polyester composite suture (Fiberwire, Arthrex) for attaching tendons. In recent in vivo studies, because of the low heat tolerance of the polyester suture, seven endoprosthesis prototypes were sterilized with VH2O2 and implanted in rabbits. Within a month post-surgery, four of the seven rabbits were confirmed to have infections around and within the endoprosthesis. The cause of the infections is not clear, and many factors could have contributed. One possible cause is that the vaporized Hydrogen Peroxide may not have effectively sterilized the endoprosthesis, including the area between the metal and silicone. The objective of this study was to compare the effectiveness of sterilization between VH2O2 and steam sterilization for the endoprosthesis without the polyester suture.
