硫酸钙骨水泥对骨质疏松性椎体强化作用的体内实验观察

目的观察硫酸钙骨水泥（CSC）在骨质疏松椎体内的组织学和生物力学表现,为椎体成形术或后凸成形术寻找更为合适的充填材料。方法对12只去势法制备的骨质疏松成年绵羊的L2～L5椎体制作骨缺损,随机注入CSC和聚甲基丙烯酸甲酯（PMMA）,并以L1和L6作正常对照。分别进行大体标本、组织学切片观察和生物力学测试。结果大体标本可见,2周时各组骨缺损处可见少量纤维疤痕形成,24周时CSC组椎体周围完全被骨性疤痕覆盖。生物力学测试显示,CSC组椎体力学性能在2周时弱于PMMA组和对照组（P〈0.05）,24周时几乎接近PMMA组和正常对照组。组织学切片显示,2周时CSC组材料与骨质接触的界面开始模糊;24周时CSC组仅见极少量的材料残留,可见成熟骨小梁贯穿骨缺损区域;PMMA组与骨质界面间出现膜性结构。结论 CSC材料同样能增强骨质疏松的椎体;随着时间的推移,CSC在体内能修复骨缺损,进一步提升椎体的力学性能。CSC材料可作为椎体成形或椎体后凸成形术的可选充填材料之一。

Observation on the role of Osteoporotic Vertebra Augmented with Calcium Sulfate Cement in vivo

Objective To observe the biomechanical and histological performance of calcium sulfate cement（CSC） in osteoporotic vertebral bodies.Methods Bone voids were created in L2~L5 vertebras of twelve female osteoporotic mature sheep.CSC and polymethylmethacrylate（PMMA） were injected into one bone voids randomly,L1 and L6 vertebrae served as the normal control.Six sheep were sacrificed at the 2nd week and the 24th week after operation respectively.Overall observation,biomechanical test and undecalcified bone histology analyses were performed.Results Biomechanical analysis showed that the vertebrae could be augmented by CSC and PMMA.The biomechanical properties of the vertebrae augmented with CSC were weakened more than that in the PMMA and normal group at the 2nd week,increased significantly at the 24th week.Histological observation showed that CSC was mostly absorbed at the 24th week,mature bone trabecula was seen in the defect area.Conclusion The osteoporotic vertebrae can be augmented instantly by CSC.As time goes on,CSC can promote bone remodeling,and enhance the vertebrae.It is an alternation for vertebroplasty and kyphoplasty.