Freeze-dried and irradiated allograft bone combined with fresh autologous coagula promotes angiogenesis in an ectopic bone allograft implantation model

ABSTRACT

Background: Freeze-dried and irradiated allograft bone (FIAB) is more easily impacted than fresh-frozen allograft bone (FAB), but has weaker incorporation efficiency. We combined FIAB with fresh autologous coagula to enhance donor-host incorporation after impaction during hip revision. Methods: Thirty adult male Sprague–Dawley (SD) rats were sacrificed for bone allograft harvesting, and nine male rats were subjected to ectopic bone allograft implantation. For each rat, the container on the left (study) side was filled with freeze-dried allograft bone powder and fresh autologous blood coagula, whereas the right (control) side was filled with freeze-dried allograft bone powder and physiological saline. The extent of angiogenesis (VEGFα) was investigated at postoperative weeks 1, 4, and 8. The deformability of the material was evaluated by performing a confined-impaction mechanical test. Results: At postoperative weeks 4 and 8, angiogenesis within FIAB on the left side was more pronounced than that on the right side. At postoperative week 1, the left side showed significantly higher VEGFα expression than that on the right side. The delta ratios of compression of the allografts were found to be influenced by bone height and impaction frequency, but not by stiffness or elastic modulus (EM). Conclusion: Supplementation with fresh autologous coagula promoted angiogenesis within the FIABs. Moreover, FIABs were equivalent to FABs in terms of deformability.

KEYWORDS:

• Allograft implantation model
• freeze-dried and irradiated allograft bone
• fresh autologous coagula
• fresh frozen allograft bone
• hip revision

Acknowledgments

We sincerely thank Dr. Shuyun Liu, Prof. Li Zhang, Dr. Xiang Sui, and Prof. Jingxiang Huang for their kind support and technical guidance.

Declaration of interest

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the article.

Funding

This work was supported by the National Natural Science Foundation (Grant No. 30973047), the National High Technology Research and Development Program 863 (Grant No. 2012AA020502), the National Natural Science Foundation of China (Key Program) (Grant No. 21134004), the National High Technology Research and Development Program of China (Grant No. 2015AA020303), and the Beijing Natural Science Foundation (Grant No. 7162186).

Additional information

Funding

This work was supported by the National Natural Science Foundation (Grant No. 30973047), the National High Technology Research and Development Program 863 (Grant No. 2012AA020502), the National Natural Science Foundation of China (Key Program) (Grant No. 21134004), the National High Technology Research and Development Program of China (Grant No. 2015AA020303), and the Beijing Natural Science Foundation (Grant No. 7162186).