Bone induction using demineralized bone in the rabbit femur: a long-term study

Area of Science:

• Orthopedics
• Biomaterials Science
• Regenerative Medicine

Background:

• Traditional autologous bone grafting for segmental bony defects presents challenges, including donor-site morbidity.
• There is a continuous need for alternative bone defect reconstruction methods that offer comparable efficacy with reduced complications.

Purpose of the Study:

• To evaluate the efficacy of demineralized bone powder in repairing significant segmental bony defects in a weight-bearing site.
• To assess the long-term functional characteristics, strength, and response to physiologic stress of demineralized bone powder-induced bone over 12 months.

Main Methods:

• A 1-cm segmental defect was created in the femur of 55 New Zealand White rabbits.
• Defects were filled with demineralized bone powder (n=38), left empty (control, n=10), or grafted with autologous bone (control, n=7).
• A titanium mandibular plate was used for stabilization; in one group, it was removed after 8 weeks, while in another, it remained for 12 months.

Main Results:

• Demineralized bone powder completely filled osteotomy gaps within 6-8 weeks in all treated animals.
• No bone formation occurred in the empty defect group; 86% success was observed with autologous bone grafts.
• While bone induced by powder with the plate in situ became thin and fractured, removal of the plate at 8 weeks allowed bone remodeling and hypertrophy, resulting in bone identical to normal femur at 12 months.

Conclusions:

• Demineralized bone powder can reliably induce bone formation across significant bony defects.
• Early removal of stabilizing hardware is crucial for proper bone remodeling and functional recovery.
• Bone-induction techniques using demineralized bone powder offer a viable alternative to autologous bone grafting, minimizing donor-site morbidity.