Positron emission tomography-CT study on posterolateral lumbar spinal fusion with recombinant human bone morphogenetic protein-2/allograft composite in a rabbit model

Abstract

Objective To investigate revascularization and osteogenesis of the fusion masses in rabbits undergoing posterolateral lumbar spinal fusion with recombinant human bone morphogenetic protein-2 (rhBMP-2)/allograft composite. Methods Forty-five adult male New Zealand white rabbits were randomly divided into 3 even groups. The rabbits in each group undergoing intertransverse process fusion at L4 and L5 respectively with rhBMP-2/allograft composite (group A), autograft (group B) and allograft (group C). 18F-NaF was injected into every rat at 2nd, 4th and 6th weeks after surgery. Whole-body radionuclide scan by PET-CT was done for all rats to evaluate the uptake values (SU V) in fusion areas. Results The SUVs for autograft and composite groups were superior to that for allograft group at 2nd, 4th and 6th weeks ( P ＜0. 05). The SUV for composite group was significantly higher than that for autograft group at the 4th and 6th weeks ( P ＜0. 05), but similar to that for autograft group at the 2nd week ( P ＞ 0. 05) . Conclusion Since the rhBMP-2/allograft composite can not only promote the bone formation but also improve the blood supply in the posterolateral lumbar spinal fusion, it may serve as a substitute material for autografts. Key words: Bone morphogenetic proteirs; Spinal fusion; Lumbar vertebrae; Tomography,spiral computed