Objective    To construct injectable tissue-engineered bone graft with fibrin glue (FG)

autologous platelet-rich plasma (PRP) and BMSCs and investigate its effect on repairing segmental radial defect in rabbits.     Methods    Thirty-six New-Zealand rabbits were randomly divided into 3 groups (n=12 in each group). A 1.5 cm segmental defect in right radius was made in each animal and three different bone grafts were implanted there respectively. Group A: FG+PRP+BMSCs

Group B: FG+PRP

Group C: FG. About a month before operation

BMSCs withdrawn from bilateral iliac bones of rabbits were cultured and multiplied in vitro. Four hours before operation

PRP was extracted from autologous arterial blood and stored at -70 ℃. Another 4 rabbits of which the same defects in radius left empty served as the blank group. At the end of 4

8

12 weeks after implantation

  two rabbits were sacrificed and specimens were taken from the part of bone defect for histological examination. At the end of 12 weeks

all animals were sacrificed and the radius were taken to analyze the biomechanics strength.     Results    In groups A and B

most FG was absorbed and substituted by newly formed cortical bone in postoperative 8 weeks. Twelve weeks later

the mature new bone with plenty of bone matrix filled in the bone defect and there formed a medullary cavity in group A. The biomechanical strength of radius in group A showed no significant statistical difference with that of normal radius (P0.05)

but was better than that in group B (P0.05).      Conclusion    Since PRP can promote healing of bone defects

the injectable bone grafts made of autologous PRP

with or without BMSCs

are effective in repairing segmental bone defect

and the presence of BMSCs could improve the new bone maturation and increase the biomechanic strength.