Characterization of an injectable chitosan-demineralized bone matrix hybrid for healing critical-size long-bone defects in a rabbit model.

The effect of injectable demineralized bone matrix (DBM) on bone repair is not known. Here, we tested the hypothesis that injectable DBM can heal a critical-size diaphyseal radius defect in a rabbit model.The bone defect was filled with DBM powder, injectable DBM or powdered, freeze-dried powdered allografts. Radiological determination, gross evaluation, histology, and micro-computer tomography was carried out 4, 8, and 12 weeks after the surgery, respectively.The injectable DBM group yielded better when compared with the freeze-dried powder group (p < 0.05). Moreover, biomechanical functionality was restored comparable to normal levels in the injectable DBM group.The injectable DBM was as effective in structurally and functionally repairing bone defects as the DBM powder and more effective than the freeze-dried bone powder. Thus, our study supports the use of injectable DBM for bone healing.