Abstract
Background:
Bone grafts are an established treatment performed for managing segmental bone defects resulting from tumors, infections, high-energy trauma, congenital deformities, and nonunion.

Aim:
To determine the regenerative potential following the sole implantation of rib, coccygeal, and A-PRF+ autografts to repair radial bone defects in rabbits.

Methods:
Radial mid-shaft defects of 10 mm were created on the left limb of 24 rabbits. The animals were randomly assigned to four groups based on the type of defect filling: control (no filler), A-PRF+, coccygeal, and rib. Diagnostic imaging modalities, including x-rays and computed tomography (CT), with macro- and micro-histopathological examinations, were employed for postoperative assessment at 6 weeks (n = 3) and 12 weeks (n = 3), respectively.

Results:
The statistical analysis of quantitative bone formation scores of diagnostic imaging and histopathology at 6 weeks postoperatively demonstrated fundamental significance differences between the rib and control groups and the coccygeal and control groups (p < 0.05). The radiographic scoring method at 6 weeks indicated a statistically significant difference between the rib and A-PRF+ groups (p< 0.01), in addition to the coccygeal and A-PRF+ groups (p< 0.01). In the CT evaluation, a significant difference was observed between the rib and A-PRF+ groups (p< 0.05). All A-PRF+ quantitatively assessed methods exhibited no statistically significant difference between the A-PRF+ and control groups at 6 weeks postoperatively. At 12 weeks, the A-PRF+, coccygeal, and rib groups presented substantial differences from the control group as evidenced by x-rays, CT scans, and both macro- and micro-histopathological analyses.

Conclusion:
The implantation of autograft rib and coccygeal bone to treat radial bone defects proved a significantly enhanced capacity for promoting bone ingrowth. Also, coccygeal vertebrae serve as a viable alternative source for bone autografts in veterinary surgery. The efficacy of A-PRF+ enhanced osseous regeneration in treated radial bone defects, but it remained inferior to rib and coccygeal autografts.

Key words: Rib bone autograft, Coccygeal bone autograft, A-PRF+, Radial bone defects, Corticocancellous autograft