应用聚甲基丙烯酸甲酯（PMMA）对新鲜尸体骨质疏松标本腰椎椎弓根钉道的强化研究

发布时间：2018-03-10 06:07

本文选题：椎弓根螺钉　切入点：骨水泥强化　出处：《山东大学》2015年硕士论文　论文类型：学位论文

【摘要】：目的椎弓根螺钉内固定系统普遍应用于脊柱后路手术中,对脊柱的稳定性起到重要的作用。在椎弓根螺钉对脊柱提供支撑稳定作用时,临床上普遍常见的一个并发症是发生在“螺钉-骨质”界面的松动,尤其是在骨质疏松患者的人群中。新型设计的椎弓根螺钉在应用于临床前,对螺钉所进行的标准生物力学实验方法为轴向拔出实验,研究其力学性能。轴向拔出力学实验数据与临床实际应用之间存在相关性。本实验研究的主要目的是评价应用聚甲基丙烯酸甲酯(PMMA)对新鲜人尸体骨质疏松标本的腰椎椎弓根钉道三种不同部位强化作用的差异性；进一步研究轴向拔出实验的结果是否与椎弓根螺钉周期抗屈实验的结果有直接的相关性。方法新鲜的人尸体骨质疏松标本腰椎椎弓根38个,每侧椎弓根均植入椎弓根螺钉一枚,在置入椎弓根螺钉前通过骨水泥注射器向钉道的不同部位注入骨水泥。根据骨水泥注入到钉道的不同部位,将新鲜的人尸体骨质疏松标本腰椎分为4组：A组,钉道未强化组(空白对照组)；B组,椎弓根部位强化组；C组,椎体部位强化组；D组,全钉道强化组。两侧的椎弓根内骨水泥的注射部位不同,对其中一侧的椎弓根进行周期抗屈实验,对另一侧进行椎弓根进行轴向拔出实验。周期抗屈实验的频率为1.OHz,于螺钉钉头位置加以正弦波形的应力,应力从25N开始逐步增加到75N。每个应力进行250个周期,每隔250个周期应力增加25N知道螺钉的钉头部位的位移为5.4mm为止。轴向拔出实验加载应力时保持螺钉的拔出速度为5mm/min。结果1.周期抗屈实验：在椎弓根螺钉钉头产生相同位移的情况下,椎弓根强化组和全钉道强化组相比,载荷差异无明显统计学意义(P0.05)；椎体强化组和椎弓根强化组、全钉道强化组相比,载荷差异有明显统计学意义(P0.05)；各强化组与空白对照组相比,载荷的差异有明显统计学意义(P0.05)。周期抗屈实验中产生相同位移的情况下,与空白对照组相比,全钉道强化组和椎弓根部位强化组均明显增加载荷约27%,椎体部位强化组降低载荷约7%。椎弓根强化组载荷比椎体部位强化组相明显增加37%。2.轴向拔出力实验：与椎体部分强化组相比,钉道椎弓根部位强化和全钉道强化组明显增加轴向拔出力,差异有明显统计学意义(P0.05)；椎弓根强化组与全钉道强化组相比,最大轴向拔出力无明显差别(P0.05)；螺钉各强化组均明显高于空白对照组,差异有统计学意义(P0.05)。结论1.对于骨质疏松性椎体,椎弓根螺钉的强化可以表现出很可靠地生物力学稳定性,不仅轴向拔出实验可以敏感的反应螺钉的生物力学稳定性,而且周期抗屈实验也是评价生物力学稳定性的重要实验。周期抗屈实验模拟的是人体在行走时螺钉所承受载荷时的力学变化。2.通过轴向拔出实验和周期抗屈实验可知,椎弓根部位的强化可明显提高螺钉的生物力学稳定性,但是其强化作用还需要进一步经过临床试验的验证。全钉道强化组虽然实验生物力学稳定性与椎弓根部位强化基本一致,但是由于其存在二次界面的原因,其远期稳定性存在一定的风险。因此临床应尽可能的在接近椎弓根部位进行强化。
[Abstract]:The purpose of pedicle screw fixation system is generally applied to the posterior spinal surgery, an important role for the stability of the spine. The pedicle screws provide support effect on the stability of the spine, a common clinical complications occurred in the "screw bone interface is loose, especially in patients with osteoporosis in the crowd. New design of pedicle screw in clinical application, the standard method of biomechanical experiment for screw pullout test, the mechanical properties of axial pullout. And there is a correlation between the clinical application of mechanical experimental data. The objective of this study is to evaluate the application of polymethylmethacrylate (PMMA) of fresh human cadaveric bone loose specimens of lumbar pedicle screw path difference of three different parts of the strengthening effect; further study of axial pullout experiment results The Shiumi Ne screw cyclic bending resistance test has a direct relationship. Methods fresh human cadaver specimens of lumbar osteoporosis Shiumi Ne 38, Shiumi Ne Shiumi Ne screws were implanted on each side of a syringe through bone cement implantation of bone cement to different parts of the screw placement in Shiumi Ne screw. According to bone cement injected into different parts of the nail the fresh human cadaveric lumbar osteoporosis were divided into 4 groups: A group, no screw augmentation group (control group); B group, Shiumi Ne group C group, part of strengthening; vertebral body augmentation group; group D, the strong nail group. Bone cement injection site on both sides of the Shiumi Ne the different, on one side of the Shiumi Ne cycle bending resistance test, on the other side of Shiumi Ne axial pullout experiment. Cyclic bending resistance test frequency is 1.OHz, the stress on the screw head position to sinusoidal waveform, stress from 25N began to stress the 250 cycle increased gradually to 75N. each, every 250 cycles of stress increased 25N know parts of the screw nail head displacement is 5.4mm. Keep the screw pull-out speed of 5mm/min. results of the 1. periodical anti bending experiment of axial pull-out test loaded stress: the nail head in pedicle screw have the same displacement situation, to strengthen Shiumi Ne group and augmentation group, there was no significant difference of load (P0.05); vertebroplasty group and Shiumi Ne group strengthened, all augmentation group, there was significant difference of load (P0.05); the strengthening group compared with the control group, there is obvious significant differences in load (P0.05). Cyclic bending resistance produces the same displacement in the experiment condition, compared with the control group, the augmentation group and Shiumi Ne group significantly increased the load strengthening parts of about 27%, vertebral body strong Group to reduce the load of about 7%. Shiumi Ne strengthened group load vertebral body augmentation group significantly increased 37%.2. phase axial pull-out experiment: compared with vertebral partial reinforcement group, screw position and strengthen the whole Shiumi Ne augmentation group significantly increased the axial pull-out, difference has obvious statistical significance (P0.05); Shiumi Ne strengthened group and the entire nail augmentation group compared with the maximum axial pull-out strength has no obvious difference (P0.05); the strengthening screw group were significantly higher than the blank control group, the difference was statistically significant (P0.05). Conclusion: 1. for osteoporotic vertebral strengthening can exhibit very reliable biomechanical stability of Shiumi Ne screw, not only the axial pullout experiment biomechanical stability sensitive reaction screw, and cyclic bending resistance experiment is important to evaluate the biomechanical stability. The cyclic bending resistance test is simulated in human walking screw The mechanical changes of.2. load through the axial pull-out test and cyclic bending resistance test shows that the reinforcement can significantly improve the biomechanical stability of screw parts of Shiumi Ne, but the strengthening effect still needs to be further validated in clinical trials. The augmentation group although the biomechanical stability and strengthening the basic parts of Shiumi Ne, but because of the there are two reasons for the long-term stability of the interface, there is a certain risk. Therefore, the clinical should as far as possible in parts of close to Shiumi Ne for strengthening.

【学位授予单位】：山东大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：R687.3

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