A Longitudinal Study on the Growth of Fusion Mass in Posterior Spinal Fusion with Advance High-resolution Peripheral Quantitative Computed Tomography - Preliminary Findings

摘要

Introduction: Various means have been attempted to enhance osteogenesis ofrnposterior spinal fusion (PSF) surgery. Stem cells treatment and biophysicalrnintervention have been shown to enhance PSF. Before optimizing the treatmentrneffect, it is necessary to understand the temporal and spatial pattern of osteogenesisrnduring the PSF. With the advanced high-resolution peripheral quantitativerncomputed tomography (HR-pQCT), the fusion mass can be monitored withrnrelatively smaller number of animals.rnObjective: The study used HR-pQCT and image analysis program to depict therntemporal and spatial pattern of osteogenesis in rabbit PSF model with bioceramic,rnosteogenic cells, and low-intensity pulsed ultrasound(LIPUS).rnMaterials and Methods: Eight rabbits undergone standardized posterior spinalrnfusion surgery with mesenchymal stem cells were randomly divided into 2 groupsrnwith or without LIPUS treatment. The animals were followed at week 1,4,10 withrnHR-pQCT to depict the bone formation at the fusion site qualitatively andrnquantitatively.rnResults: Bone formation was not limited to the transverse processes at the fusionrnsite but also around and within the implanted material. The bone mineral contentrnof the fusion mass in LIPUS treated animal enhanced by 15-20%. Different patternrnof bone formation was observed in LIPUS treated animal.rnConclusion: HR-pQCT is a feasible and non-invasive method allowing thernuncoverage of important, new information of bone microstructure in spinal fusionrnsequentially. The LIPUS can enhance the bone formation in the implant ofrnposterior spinal fusion.rnSignificance: The new HR-pQCT monitor enables better understanding of thernbiology mechanism and sequence of bony fusion in vivo for further research inrnenhancement of spinal fusion.