In light of the recently described experimental technique of in vivo bone reconstitution with biotechnologic methods (from bone marrow stromal cells) and the prefabrication flap procedures, the possibility to obtain autologous bone growth in a myocutaneous flap, thus creating a composite osteomyocutaneous preformed flap, is postulated. Human bone marrow stromal cells were delivered into the latissimus dorsi of athymic mice by a porous hydroxyapatite ceramic model. Eight weeks after the implantation, histologic examination revealed the presence of spongious bone tissue. A simple myocutaneous flap was thus transformed into a composite osteomyocutaneous flap. This flap is called the biotechnologic prefabricated flap, because it was the result of ex vivo expanded osteogenic precursor cells and in vivo bone tissue neoformation. The shape of the bone flap was exactly the same as the shape of the ceramic model used. A possible clinical application may be the correction of skeletal defects. The advantages of this procedure are simple surgical execution, the possibility of preshaping the graft to the exact characteristics of the defect, and the availability of autogenous donor tissue without donor site morbidity.