FIG. 1.

Schematic of engineered vascularized bone graft development in an in vivo bioreactor and subsequent transplantation to tibial defect. In Phase 1, the osteoinductive growth factor-impregnated 3D printed scaffold was implanted into the vascular enriched muscle pouch to allow for microvascular invasion, whereas the osteoinductive factor in the scaffold promoted ectopic bone formation. In Phase 2, after maturation, the vascularized bone graft was transplanted into a critical segmental tibial defect to accelerate bone healing and restoration of function. 3D, three-dimensional.