中文摘要：

目的研究松质骨粒移植增强和骨水泥增强对椎体治疗节段和相邻非治疗节段的生物力学相容性影响,探讨椎体重建前后的荷载传导机制。方法选取正常男性青壮年脊柱L1～L2节段标本进行薄层CT扫描,构建正常的和骨折复位后疏松的功能脊柱单元三维有限元模型,模拟经皮穿刺椎体后凸成形术（PKP）在L2椎体中心注入骨水泥,模拟经皮骨移植（Optimesh）在L2椎体中心置入松质骨粒,按照脊柱三柱理论施加轴向压缩、前屈和后伸荷载进行有限元分析。结果与骨质疏松模型相比,松质骨粒移植增强或骨水泥增强后相邻节段椎体应力应变的变化甚微;治疗节段增强区域的应力应变明显改变。另外,骨质疏松、松质骨粒移植增强、骨水泥增强对脊柱三柱轴向压缩位移和椎间盘平均内压没有影响。结论松质骨粒移植增强和骨水泥增强均能恢复骨折椎体的总体刚度和强度,有利于椎体功能重建;但从椎体与增强材料间的力学相容性和生物相容性的观点看,松质骨粒移植增强优于骨水泥增强。

英文摘要：

Objective To investigate the biomechanical compatibility effects of cancellous bone granule （CBG） augmentation of Optimesh and polymethylmethacrylate （PMMA） augmentation of Kyphoplasty on treated and adjacent non-treated vertebral bodies. Method Three-dimensional,anatomically detailed finite element （FE） models of the L1~L2 functional 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. Conclusions 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.