骨水泥和骨泰应用于椎体后凸成形术的实验研究

目的探讨骨水泥（PMMA）和注射性骨泰（CPC）在椎体后凸成术中对不同骨密度椎体的生物力学恢复情况。方法选60个椎体，按骨密度分正常对照组、轻中度和重度骨质疏松组，即A、B、C组。测高后轴向加载，压缩椎体高度25％，得出初始压缩强度和刚度。行椎体后凸成形术后（记球囊扩张体积），随机注入PMMA或CPC，观察外渗情况及注入量。同术前测高压缩，确定术后压缩强度和刚度。结果A组CPC和PMMA材料未能恢复椎体的初始压缩强度和刚度（P〈0．05）；B组中均恢复，而C组中刚度均恢复（P〉0．05）。所有标本未发现骨水泥外渗，术后椎体高度恢复CPC组为95．3％；PMMA组为95．2％。结论CPC可作为PKP术中PMMA的替换材料，尤其是在年青患者中，但需临床和实验进一步论证。

Experimental Studies of Kyphoplasty with the Domestic Polymethylmetharylate and Injectable Calcium Phosphate Cement

Objective To investigate the biomechanical changes of isolated, fractured VBs after treatment by Kyphoplasty(KP) with one of two domestic cements: polymethylmetharylate(PMMA) or injectable calcium phosphate cement(CPC). Methods Sixty VBs were harvested from embalmed cadavers. According to their BMD,The VBs were divided into: normal (A);osteoporotic (B);and serious osteoporotic group(C). All VBs were compressed in a materials testing machine to determine initial intensity and stiffness values, were assigned to one of two groups, and were then repaired using KP with the domestic PMMA or CPC. Re-compressed as pretreatment to determine post-treatment intensity and stiffness values. The volumes of the expanded IBT(an inflatable tamp) and injected cement were recorded.Results The pretreatment intensity and stiffness were recovered in all VBs of groups B and C, whereas not recovered in group A. The heights of VB were recovered to 95% of initial ones. Extravasation was not found in either VBs.Conclusion CPC can be used in KP, but have yet to be substantiated in more studies.