Critical Analysis of Induction Capability of Bone Allograft

Background: To avoid the problems associated with harvesting autogenous donor graft bone, substitutes have been developed to act as an osteoconductive matrix and provide osteoinductive potential. The efficacy of any bone-graft material depends upon the presence of osteoblasts, or stem cells that can develop into osteoblasts, and cytokines and growth factors that regulate the bone-formational work of the osteoblasts. Purpose: To investigate whether commercially available allograft materials contain RNA, an essential precursor to production of the cytokines and growth factors necessary to induce bone formation. Materials and Methods: Seven commercially available allograft samples were genetically analyzed, along with samples of peripheral blood from two randomly chosen patients, to determine the presence of RNA as an indicator of cytokines and growth factors. Results: Although RNA was found in both the venous blood samples and the commercial allograft samples, the RNA in all the allograft samples was found to be substantially degraded. The blood samples contained intact RNA. Conclusion: Because the allograft samples that were analyzed lacked intact RNA, they cannot be considered to be osteoinductive. However, the addition of peripheral blood and/or bone marrow aspirate to the graft materials could add osteoinductive capability and thus enhance the chances for bone-grafting success.