在扭矩作用下股骨和外固定器钢针上各测点的应变电测量  

Strain measurement of the femur and external fixation device steel needle under different torques

作　　者：穆德龙[1] 徐国安[1] 马洪顺[2] 李治罡 

机构地区：[1]吉林大学教育技术中心,吉林省长春市130022 [2]吉林大学南岭校区工程力学系,吉林省长春市130022 [3]吉林省中医院,吉林省长春市130021

出　　处：《中国组织工程研究与临床康复》2008年第26期5007-5010,共4页Journal of Clinical Rehabilitative Tissue Engineering Research

摘　　要：背景:课题组前期已经研究了股骨颈骨折外固定器结构模型的三维有限元计算与压应力分布实验。目的:以应变电技术测量在扭矩作用下股骨和外固定器钢针上各测点的应变值,验证外固定器的设计是否符合生物力学原理。设计、时间及地点:观察性实验,于2006-08-12/15在吉林大学力学实验中心完成。材料:自行设计股骨颈骨折外固定器。电阻应变片由浙江省黄岩测试仪器厂生产,YJ-X2型静态电阻应变仪由上海华东电子仪器厂生产,新鲜尸体股骨由吉林省中医院提供,扭矩测量仪为上海市金汇电动工具厂生产。方法:模拟股骨颈骨折外固定器固定后,在股骨干和外固定钢针上粘贴电阻应变片,对标本施加扭矩,通过静态电阻应变仪分别测50N·cm、100N·cm、150N·cm扭矩时的应变与应力值。主要观察指标:承受扭矩时的应变与应力值。结果:测量应变不成线性关系,但是施加扭矩越大,各测点应力越大。长钢针(B)内侧最大应力为(1.99±0.19)MPa,短钢针(C)外侧最大应力为(1.49±1.28)MPa,股骨上端最大应力为(3.42±0.26)MPa。结论:外固定器固定股骨颈骨折具有很好的抗扭转能力,应变和应力很小。外固定器设计符合生物力学原理。BACKGROUND： Previous studies have analyzed three-dimensional finite element model and stress distribution of the femoral neck fracture fixed structure. OBJECTIVE： Using strain measurement principle, to measure the stress values of each points of femur and external fixation device steel needle under different torques, and to verify whether the design accords with the principles of biomechanics. DESIGN, TIME AND SETTING： The observation was performed at the Experimental Center of Mechanics, Jilin University from August 12^th to 15^th, 2006. MATERIALS： Self-designed external fixator of femoral neck fracture; resistance stain chip （Zhejiang Huangyan Testing Apparatus Factory）; YJ-X2 static resistance strain gauge （Shanghai Huadong Electronic Instrument Works）; fresh corpse femur （Traditional Chinese Medical Hospital of Jilin Province）; torque measurement devise （Shanghai Jinhui Power Tools）. METHODS： The simulated model of femoral neck fracture was fixed by the external fixation device, and the resistance strain chips were pasted on the femoral shaft and external fixation steel needle, then torque was imposed on the specimens. Stress and strain values under different torques （50 N · cm, 100 N· cm, 150 N· cm） were measured using static resistance strain gauge. MAIN OUTCOME MEASURES： Stress and strain values under different torques. RESULTS： The more the torque, the greater the stress was. The maximum stress of medial long steel needle （B） was （1.99±0.19） MPa, that of lateral short steel needle （C） was （ 1.49 ± 1.28） MPa, and that of upper femur was （3.42 ± 0.26） MPa. CONCLUSION： The design of the external fixation device for femoral neck fracture is in accordance with biomechanical principles. It has good anti-torquing strength, and minimal stress and strain.

关 键 词：股骨颈骨折 外固定器 扭矩 

分 类 号：R681[医药卫生—骨科学]