Optimal regenerative repair of large segmental bone defect in a goat model with osteoinductive calcium phosphate bioceramic implants

• Published in: Bioactive materials Vol. 11; pp. 240 - 253
• Main Authors: Zhi, Wei, Wang, Xiaohua, Sun, Dong, Chen, Taijun, Yuan, Bo, Li, Xiangfeng, Chen, Xuening, Wang, Jianxin, Xie, Zhao, Zhu, Xiangdong, Zhang, Kai, Zhang, Xingdong
• Format: Journal Article
• Language: English
• Published: China Elsevier B.V 01.05.2022; KeAi Publishing; KeAi Communications Co., Ltd
• Subjects: Bone regenerative repair; Calcium phosphate bioceramics; Large segmental bone defects; Mechanical stability; Osteoinduction; Large segmental bone defects; Mechanical stability; Calcium phosphate bioceramics; Bone regenerative repair; Osteoinduction
• ISSN: 2452-199X; 2452-199X
• DOI: 10.1016/j.bioactmat.2021.09.024

So far, how to achieve the optimal regenerative repair of large load-bearing bone defects using artificial bone grafts is a huge challenge in clinic. In this study, a strategy of combining osteoinductive biphasic calcium phosphate (BCP) bioceramic scaffolds with intramedullary nail fixation for creating stable osteogenic microenvironment was applied to repair large segmental bone defects (3.0 cm in length) in goat femur model. The material characterization results showed that the BCP scaffold had the initial compressive strength of over 2.0 MPa, and total porosity of 84%. The cell culture experiments demonstrated that the scaffold had the excellent ability to promote the proliferation and osteogenic differentiation of rat bone marrow-derived mesenchymal stem cells (BMSCs). The in vivo results showed that the intramedullary nail fixation maintained the initial stability and structural integrity of the implants at early stage, promoting the osteogenic process both guided and induced by the BCP scaffolds. At 9 months postoperatively, good integration between the implants and host bone was observed, and a large amount of newborn bones formed, accompanying with the degradation of the material. At 18 months postoperatively, almost the complete new bone substitution in the defect area was achieved. The maximum bending strength of the repaired bone defects reached to the 100% of normal femur at 18 months post-surgery. Our results demonstrated the good potential of osteoinductive BCP bioceramics in the regenerative repair of large load-bearing bone defects. The current study could provide an effective method to treat the clinical large segmental bone defects. [Display omitted] •A novel strategy of achieving regenerative repair for large segmental bone defects with osteoinductive calcium phosphate bioceramics was developed successfully.•The critical-sized goat femur defects (3.0 cm in length) were completely repaired by osteoinductive calcium phosphate bioceramics without using exogenous active factors or cells.•The current study could provide an effective method to solve the clinical problem about large load-bearing bone defect repair.