(34c) Bone Sterilization Via Dense Gases: Importance in Orthopaedic Reconstruction Surgery

Significant limitations in the surgical implant of bone allograft are the potential for cross-infection and the preservation of the mechanical strength of bone. In this study, whole mature rat femurs were used as analogues for strut allograft. Bones were contaminated with Staphylococcus epidermidis and Pseudomonas aerugenosa - which are common contaminants of bone allograft and are pathogenic in vivo - and with Bacillus subtilis - a spore forming pathogen which is resistant to decontamination procedures. Inoculated bones were subjected to a sterilization procedure utilizing CO2 and subsequently tested for residual bacterial load and mechanical properties. Untreated-, gamma irradiated- and dehydrated bones were used as controls. The dense gas treatment decontaminated the bones well within acceptable limits whilst preserving their mechanical properties. Dense gas sterilization can address the limitations of bacterial transmission and mechanical strength enhancing the potential for the use of bone allograft in orthopaedic and trauma reconstruction surgery.