Synergy between living bone particles and rhBMP-2 in the healing of large segmental defects in the rat femur

Introduction Large, segmental, osseous defects remain a major clinical problem. Common approaches to healing such defects include the use of autograft bone and the application of recombinant, human bone morphogenetic protein-2 (BMP-2) in the form of InfuseTM. Neither, however, is ideal. Supplies of autograft are limited and its harvest can be associated with considerable morbidity. BMP-2 is extremely expensive and its clinical performance in long bone healing is modest. Moreover, new analyses of data from the use of BMP-2 in spinal fusion suggest the potential for considerable, adverse side effects. The present study examined the potential for synergy between living bone particles and BMP-2 that, if present, could reduce the need for both autograft and BMP-2, thereby reducing costs and increasing safety. Bone particles were recovered with a device known as the “Reamer-Irrigator-Aspirator” (RIA) that recovers small osseous particles as it reams the intramedullary canal, and is increasingly used as a source of autograft.