硫酸钙骨水泥强化椎弓根螺钉稳定性的体内实验研究  

In vivo study of pedicle screw augmentation using calcium sulfate cement

作　　者：刘达[1] 雷伟[1] 吴子祥[1] 万世勇[1] 张伟[1] 秦为径[1] 战策[1] 

机构地区：[1]第四军医大学西京医院全军骨科研究所,西安市710032

出　　处：《中国脊柱脊髓杂志》2009年第6期446-450,共5页Chinese Journal of Spine and Spinal Cord

基　　金：国家高技术研究发展计划(863计划)(2007AA02Z468)

摘　　要：目的：评价硫酸钙骨水泥（calcium sulfate cement，CSC）在动物体内强化椎弓根螺钉稳定性的效果，观察钉道界面及材料吸收的情况。方法：4只健康成年山羊，L2～L5每个椎体的一侧椎弓根直接拧入螺钉（空白组），另一侧填充CSC后拧入螺钉（实验组）。3个月后处死山羊，随机选择6个椎体（12个螺钉），对其两侧钉道进行显微CT扫描、骨计量学分析和组织学观察；其余10个椎体（20个螺钉）进行轴向拔出试验。结果：显微CT三维重建及骨计量学分析显示实验组钉道周围骨小梁数量及密度明显优于空白组，差异有统计学意义（P〈0．05）；组织学观察示实验组钉道周围CSC绝大部分已经降解吸收，大量新生骨组织紧密包裹螺钉，形成良好的钉骨结合，界面明显优于空白组，螺钉周围骨小梁明显较空白组致密，仅有少量骨髓腔内仍可见残留的未降解材料；实验组的最大轴向拔出力为914．80±162．88N，能量吸收值1．752±0．214J，空白组为682．50±112．15N和1．437±0．173J，两组间差异均有统计学意义（P〈0．05）。结论：CSC可以显著增强动物体内椎弓根螺钉的固定强度；随着CSC的降解吸收，大量新骨生成并紧密包绕螺钉，形成良好的钉置结合，为螺钉在体内的远期稳定性提供了良好的骨质条件。Objective：To evaluate effect of pedicle screw augmentation using calcium sulfate cement（CSC） in vivo and the disolvement of the interface between instrument and CSC.Method：Sixteen lumbar vertebrae （L2- L5） from 4 healthy and adult goats were employed in this experiment.Before pedicle screw implantation,a screw channel was made on unilateral pedicle without CSC augmentation （control group） and the correspondence on contralateral pedicle was augmented with CSC （experiment group）.After three months,all goats were sacrificed and six vertebrae randomly collected from all samples were 3D-imaged and reconstructed by Micro- CT.After that histology was used to evaluate the microstructure.and axial pull-test was performed to the other ten vertebrae（20 serews）.Result：The bone trabeculae around the screw channel in experiment group was significantly more and denser than that in control group.In experiment group,CSC around the screw channel histologically had almost been degraded and much newly formed bone trabeculae warapping around screw tightly which formed excellent connection between bone and screw.There were more compact trabecular structure and better interface in experiment group than those in control group.Only little undegraded CSC was found in eavitas medullaris.The maximal axial pullout strength was 914.80±162.88N and energy absorption value was 1.752±0.214J in experiment group respectively,which were significantly higher than those of 682.50±112.15N and 1.437±0.173J in control group respectively （P〈0.05）.Conclusion：Augmentation with CSC can significantly strengthen the pedicle screw biomeehanically in vivo.With degradation and adsorption of CSC in vivo,much new bone tissue wrapping screw tightly come into being excellent connection between bone and screw,which provides favorable osseous condition for long-term stability of pedicle screw in vivo.

关 键 词：椎弓根螺钉 硫酸钙骨水泥 显微CT 最大轴向拔出力 能量吸收值 

分 类 号：R687.3[医药卫生—骨科学] R318.01[医药卫生—外科学]