Biomechanical compatibility of osteoporotic vertebral augmentation with cancellous bone granules and bone cement: a finite element evaluation / 医用生物力学

ABSTRACT

Objective The goal of this study was to investigate the biomechanical compatibility effects of cancellous bone granule(CBG) augmentation of Optimesh and polymethylmethacrylate (PMMA) augmentation of Kyphoplasty on treated andadjacent non-treated vertebral bodies. Methods Three-dimensional, anatomically detailed finite element (FE) models of the L1–L2functional spinal unit (FSU) were developed on the basis of cadaver computed tomography (CT) scans. The material properties and plug forms of the L2 centrum were adapted to simulate osteoporosis, CBG and PMMA augmentation. The models assumed a three-column loading configuration as the following types compression, flexion and extension. Results Compared with the osteoporotic model, changes in stress and strain at adjacent levels both of CBG and PMMA augmentation models were minimal, but stresses/strains within the two reinforcement material plugs were modified distinctly and differently. In addition, osteoporosis, CBG and PMMA augmentation had little effect on either the axial compressive displacement of the three columns or the average disc internal pressure in all models. Conclusion Both morcelized cancellous bone and PMMA augmentation restore the total strength and stiffness level of treated vertebral bodies and benefit the reconstruction of vertebral function. Regarding the biomechanical compatibility and the biocompatibility of the treated vertebral body and reinforcement material, however, the morcelized cancellous bone is better than PMMA augmentation.