[The value of perforating cryopreserved massive bone allograft. Histologic data of an allograft removed after 27 months].

The authors reported one documented observation of a deep-frozen, non irradiated, intercalary allograft; it was perforated by drilling and then fixed by a blade plate. This allograft was removed 27 months after its implantation. Histological examination of the removed bone graft showed newly formed mature bone which developed near preexisting devitalized bone. The external cortex was also revitalized and reossified close to the periosteum, as it was previously reported. But osteogenesis filled all the paths of the perforations and extended to the haversian canals located in the vicinity of the perforations. The authors conclude that cortical perforations induce both cortical and medullary osteogenesis of the graft. If osteogenesis is observed in the whole medullary canal, it is more focal and located in the vicinity of the holes in the cortex.