Preparation of beta-tricalcium phosphate microsphere-hyaluronic acid-based powder gel composite as a carrier for rhBMP-2 injection and evaluation using long bone segmental defect model

The specific objective of this study was to evaluate whether rhBMP-2-loaded bio-scaffolds can be used as effective rhBMP-2 carriers in the implantation of bone defect sites or poor bone quality in host bone. The rhBMP-2 release pattern test showed slow results in both groups, and a 1:9 ratio composition with a high water-absorption rate was selected for in vivo study. All animals euthanized after 9 weeks. The new bone formation and bone quantity and quality of fibular samples were examined. The results showed that the rhBMP-2 powder gel composite improved the new bone formation in the cortical bone and the marrow space. The length of new bone formation ratio of the rhBMP-2 loaded composite group was significantly higher than the powder gel group. The composite of powder gel seems to be a nice carrier, and slow release of rhBMP-2 can promote new bone formation in a segmental cortical bone defect after implantation.