Release of BMP-2 and Tobramycin from Injectable, Biodegradable Polyurethane Scaffolds for Enhanced Bone Fracture Healing

摘要

Nonunions are a significant clinical problem for civilians and military personnel. A 2004 report (Capturing the Full Power of Biomaterials for Military Medicine)1 published by the National Research Council recognizes the potential for further development of bioactive materials that promote bone healing and decrease the incidence of non-unions. Military applications of bone graft materials incorporating bioactives that promote bone healing will be practical and realistic over the next 3 to 5 years. The report lists desirable characteristics and properties for a material to promote bone healing: (1) Enhancement of the development of new blood vessels that serve to promote healing and preventing infections during bone and muscle repair. (2) Ease of use (e.g., pastes and injectables that harden and cure in vivo). (3) Biodegradability: degradation at a rate equal to that of bone healing in vivo. (4) Bioactivity: controlled release of a wound-healing accelerant over a period of 1 to 3 weeks. Infections are a significant clinical problem for civilians and military. Early reports indicate that approximately 65% of the wounds from the Iraq conflict culture positive for bacteria. Open fractures are a common source of these infections, and represent the most challenging to treat. In a previous conflict, 4 of 11 open fractures became infected (3 of the 5 tibial fractures). The soldiers who had complications, such as infection or non-union, had the longest hospital stay.