Biomechanical Integrity of Human Allograft Bone After Sterilization

Musculoskeletal allografts have been used extensively for a variety of orthopaedic procedures. Allograft does have the potential, however, to transmit a variety of pathogens. Two current sterilization methods widely used in the tissue banking industry are ethylene oxide (ETO) treatment and gamma irradiation. ETO has been shown to adversely affect the biologic incorporation of allograft tissue. Gamma irradiation has been shown to have an adverse effect on the mechanical properties of tissue at certain doses. A novel sterilization process for allografts, the BioCleanse Tissue Sterilization Process, has been implemented that addresses the potential for disease transmission. Two studies, both using the BioCleanse process, were performed that examined the effects of various treatment regimes on the biomechanical properties of bone. The first study investigated effects of the BioCleanse process on the mechanical properties of bone. The second study evaluated bone through various processes, including the BioCleanse process combined with a terminal sterilization step in the final packaging. Figure 1. Studies found that after 5 minutes contact time (normal cycle: 218 minutes), The BioCleanse process completely perfused inner matrices of cortical and cancellous bone with sterilants.