Revascularized segmental diaphyseal bone transfers in the canine. An analysis of viability

The biologic behavior of free revascularized bone segments was investigated using a unique canine model. Conventional methods to assess bone kinetics included the histologic osteocyte count, tetracycline uptake, appositional bone formation rate, and quantitative microradiography. The percentage of viable osteocytes in the revascularized segment was 52.4%, compared with 66.8% in the normal controls and 28.5% in the nonrevascularized segment. These differences were statistically significant. Both qualitative and quantitative differences were noted regarding deposition of tetracycline. On the basis of this study, we conclude that an apparently successful vascularized bone transfer retains a degree of viability greater than a conventional bone graft but less than that of normal undisturbed bone.