骨水泥修复颈椎前路椎体螺钉钉道的生物力学研究  

Restoration screw channel of pedicle screw fixation with polymethylmethacrylate: in vitro biomechanical study

作　　者：陈利帮 陈春[2] 顾韬[3] 

机构地区：[1]皖西卫生职业学院,安徽237000 [2]温州医科大学附属第一医院骨科 [3]海军总医院骨科

出　　处：《脊柱外科杂志》2015年第4期238-242,共5页Journal of Spinal Surgery

摘　　要：目的评价聚甲基丙烯酸甲酯（Polymethylmethacrylate,PMMA）修复颈椎前路椎体螺钉钉道的生物力学效果。方法防腐成人颈椎标本（C3~7）共30个,分3组：正常骨密度组（A组）、骨质疏松组（B组）,骨质疏松修复组（C组）,各组10个标本,测试疲劳前后的最大轴向拔出力。A、B对照组椎体二侧钉孔均放置4 mm的椎体螺钉,随机选择一侧行即时最大拔出力实验,另一侧在疲劳实验（2 Hz,20 000次）后行最大拔出力实验。C组（实验前需进行螺钉拔松实验）注入PMMA 0.6~1.0 m L,并拧入螺钉,随机选择一侧进行即时和疲劳后最大拔出力实验。结果 A、B、C组即时拔出力明显高于疲劳后拔出力,差异具有统计学意义（P〈0.05）,C组疲劳后与A组即时拔出力比较,差异无统计学意义（P〉0.05）,但高于B组即时拔出力,差异具有统计学意义（P〈0.05）。即时拔出力C组〉A组〉B组,差异均有统计学意义（P〈0.05）。疲劳后拔出力C组〉A组〉B组,差异均有统计学意义（P〈0.05）。PMMA注射后未发现钉道渗漏。结论 PMMA钉道修复能够明显增强椎体螺钉的即时稳定性和抗疲劳能力,并且安全有效,适用于螺钉松动和拔出的修复固定。Objective To evaluate the biomechanical efficacy of polymethylmethacrylate（ PMMA） in restoration screw channel of anterior cervical unicortical screw fixation. Methods Thirty vertebral bodies（ C3-7） were from 10 formalin adult corpses（ Laboratory of Anatomy,Southern Medical University）,and 30 vertebral bodies（ 10 for each group） were randomly selected and divided into 3 groups（ A： healthy group; B： osteoporosis group; C： restoration group）. All specimens were subjected to pullout forces testing on Bose3510-AT fatigue testing machine,and measurements were taken before and after fatigue. In control groups A and B,2 pilot holes on each side of 20 vertebral bodies were implanted with vertebral screws.Each side randomly received either acute pullout forces or pullout forces beyond fatigue which was ensured using cyclical loading（ 2 Hz,20 000 times）. In group C,pilot holes were drilled parallel to sagittal plane,then injected with 0. 6-1. 0 m L of PMMA before the vertebral screw was inserted. Similar to groups A and B,the sides were randomly chosen to evaluat acute pullout forces and pullout forces beyond fatigue. Results The acute pullout forces were obviously higher than pullout forces beyond fatigue in each group（ P〈0. 05）. Compared pullout forces beyond fatigue of group C to acute pullout forces of group A,there was no significant differences（ P〈0. 05）. Compared to acute pullout forces of group B,there was significant differences（ P〈0. 05）. The acute pullout forces,group C group A group B（ P〈0. 05）. The pullout forces beyond fatigue,group C〉 group 〉A group B（ P〈0. 05）. No PMMA leakage was found in the screw channel.Conclusion Restoration screw channel of pedicle screw fixation with polymethylmethacrylate can improve primary stability of screw and its anti-fatigue ability. It is safe and effective to restore and fix the screw loose and pulled-out.

关 键 词：颈椎 聚甲基丙烯酸类 生物力学 内固定器 

分 类 号：R318.08[医药卫生—生物医学工程]