Degradable Bone Graft Substitute for Effective Delivery of Multiple Growth Factors in the Treatment of Nonunion Fractures.

摘要

Our hypothesis was that a degradable, thermally-responsive bone graft substitute, made from renewable sources, that effectively and simultaneously delivers osteogenic and angiogenic growth factors directly to the bone defect site can enhance repair of non-union fractures. In this study, a new chitosan/xylan composite hydrogel was studied as an improved bone graft substitute able to accurately deliver a combination of proven growth factors in a manner that is compatible with current surgical practice. This new bone graft substitute has immediate implications for clinical care of segmental bone loss and the acceleration of healing in traumatic bone injuries. The goal was to provide surgeons with an effective and reliable method for simultaneous delivery of synergistic growth factors. The thermally-responsive behavior of this new material allows surgeons to use stabilization methods in which they have confidence while at the same time enabling accurate delivery of precise quantities of synergistic proteins that are beneficial to healing. While the protein delivery aspect of this study did not succeed, treatment with the new xylan/chitosan hydrogel alone was enough to heal serious fractures that did not heal without treatment.