Collagen particles with collagen-binding bone morphogenetic protein-2 promote vertebral laminar regeneration in infant rabbits

The vertebral laminar defects caused by severe spina bifida occulta, spinal fracture, or bone tuberculosis require surgical treatment. The reconstruction of vertebral laminar defects remains challenging, especially in children. In this study, we created an animal model of vertebral laminar defects in newly weaned rabbits to evaluate the therapeutic effect of bovine bone collagen particle (BBCP) that combined with bone morphogenetic protein-2 with collagen binding domain (CBD-BMP-2). The tissues at the injury site which were harvested after 12 weeks indicated that newly formed bone was observed in both BBCP and BBCP/CBD-BMP-2 groups, whereas the injury site of the control group was mostly filled by fibrous tissue. The BBCP/CBD-BMP-2 group recovered better than the BBCP group. These findings indicate that a combination of BBCP with CBD-BMP-2 may be a good strategy for vertebral laminar defects in children.