不同弹性模量膨胀式椎弓根螺钉在骨质疏松生物力学实验模块中的比较研究  

Comparison of expandable pedicle screw with different elastic modulus in osteoporotic biomechanical test blocks

作　　者：石磊[1] 王陵[2] 雷伟[1] 付索超[1] 吴子祥[1] 刘达[1] 高明暄[1] 

机构地区：[1]第四军医大学西京医院全军骨科研究所,陕西西安710032 [2]第四军医大学卫生统计教研室,陕西西安710032

出　　处：《中国现代医学杂志》2011年第26期3245-3248,共4页China Journal of Modern Medicine

基　　金：国家高技术研究发展(863计划)(No:2007AA02Z468)

摘　　要：目的比较两种不同弹性模量膨胀式椎弓根螺钉在骨质疏松生物力学实验模块中的稳定性。方法 30块骨质疏松生物力学实验模块随机分为3组。采用相同方法制备钉道后,普通椎弓根螺钉(CPS)组拧入CPS,弹性模量110 GPa;普通膨胀式椎弓根螺钉(H-EPS)组拧入EPS,弹性模量110 GPa;低弹性模量膨胀式椎弓根螺钉(L-EPS)组拧入L-EPS,弹性模量42 GPa。对所有标本进行X线检查,然后行轴向拔出实验。待螺钉拔出后观察各组中的破坏情况,并测量各组中出口处的直径(D)。结果 X线检查显示,CPS、EPS和L-EPS各组中,螺钉均被周围PU材料紧密包绕,同时EPS组和L-EPS组螺钉的前端在模块内明显膨胀,形成一个"爪状"结构。EPS组和L-EPS组螺钉的稳定性均强于CPS组(P<0.05),螺钉拔出后,EPS组和L-EPS组的直径均高于CPS组(P<0.05),但是,无论是稳定性还是直径,在EPS组和L-EPS组之间差异无统计学意义。结论 EPS和L-EPS都可以显著提高螺钉在骨质疏松生物力学实验模块中的稳定性,同时二者无差异。【Objective】 To compare stability of expansive pedicle screw（EPS） with different elastic modulus in osteoporotic biomechanical test blocks.【Methods】 Thirty osteoporotic biomechanical test blocks were randomly divided into three groups.A pilot hole was prepared in advance using the same method in all samples.Then,conventional pedicle screw was inserted in CPS group（elastic modulus 110 GPa）,the conventional EPS was inserted in EPS group（elastic modulus 110 GPa） and the EPS with low elastic modulus（L-EPS） was inserted in L-EPS group（elastic modulus 42 GPa）.X-ray examination and axial pull-out tests were performed to all groups.Then,the destruction of blocks was observed and the diameter（D） of holes was measured.【Results】 X-ray examination revealed that all the screws were surrounded by polyurethane material,meanwhile the anterior part of EPS and L-EPS presented obvious expansion in blocks and formed uniform structure.Biomechanical data revealed that screw stability in both L-EPS group and EPS group were significantly enhanced compared with those of screws in CPS group（P〈0.05）.The diameters of holes in EPS group and L-EPS group were significant bigger than that in CPS group（P〈0.05）.But there was no difference in screw stability or diameters of holes between the group EPS and L-EPS group.【Conclusions】 Both EPS and L-EPS can significantly increase screw fixation strength in osteoporotic biomechanical test blocks,and there is no significant difference between them.

关 键 词：疏松 膨胀式椎弓根螺钉 弹性模量 生物力学 生物力学实验模块 

分 类 号：R318.01[医药卫生—生物医学工程]