摘要
目的 通过在实体胫骨上对两种不同弹性模量的外固定材料进行生物力学测试，探讨两种不同弹性模量的外固定材料对胫骨骨折应力及其分布的影响。方法 选择12套成人尸体胫骨，将胫骨中段横行锯断，制作胫骨骨折模型。将骨折标本解剖复位后分别以铝合金材料外固定支架（高弹性模量，弹性模量为110 GPa）和PEEK、碳纤维树脂材料外固定支架（低弹性模量，弹性模量为7.0 GPa及11.4 GPa）固定。在骨折断面及钉道周围共粘贴13个电阻应变片，然后将模型分别置于Zwick Z100电子万能材料实验机及扭转试验机（RNJ-500）上，以线性载荷0 ~ 600 N、扭转载荷0 ~ 2.5 N？m加载，分析局部应力，测量两种不同材料外固定系统在相同载荷条件下骨折断面及钉道周围应力的大小和分布特点。结果 在实验载荷条件下，传统外固定支架和高分子外固定支架骨折断端和钉道周围应力均随着轴向载荷或扭转载荷的增大而增大。在同一线性载荷或扭转载荷下，高分子外固定支架组较传统外固定支架组在13个测试应变点应变值应力分布更均匀，应变值大，其差异均有显著统计学意义（P 〈 0.01）。 结论 高分子材料外固定器治疗骨折中可明显降低应力遮挡，从而利于应力传导，从生物力学角度可以推广使用。
Objective To explore the effects of external fixation systems with 2 different modulus of elasticity on the stress, and discuss its distribution at tibial fracture through biomechanical testing. Methods Twelve sets of adult cadaveric tibia were selected, and the middle of tibias was sawn with an electric saw to form tibia facture models. After anatomic reduction, the fracture samples were fixed with different external fixators, included high elastic modulus （elastic modulus of 110 GPa） which was made of aluminum alloy material and the low elastic modulus（elastic modulus of 7.0 GPa or 11.4 GPa） made of polyetheretherketone（PEEK） or carbon fiber resin material. Thirteen strain gages were mounted near the fracture plane and pin track, then the models were placed in Zwick Z 100 electronic universal material test machine and torsional testing machine（RNJ-500） and were given linear load of 0 - 600 N and torisional load of 0 - 2.5 N. m to detect the stresses and their distributions under the same load in 2 external fixation systems with different modulus of elasticity. Results In the experimental condition, the traditional external fixation, high external fixation stress at fracture end and around pin track were increased with an increasing load. In the same linear or torsional loads, the polymer external fixator group was symmetrical and larger than the traditional external fixator group in 13 test strain point, and the difference between 2 groups were significant （P 〈 0.01）. Conclusion It is demonstrated that polymer material made external fixator could reduce stress-shielding, which is beneficial to the stress conduction and could be at3plied in clinical practice.
出处
《生物医学工程与临床》
CAS
2013年第5期420-424,共5页
Biomedical Engineering and Clinical Medicine
基金
亚洲创伤骨科学会(AADO)研究基金资助项目(AADO-RF2011-002-2Y)
关键词
胫骨骨折
外固定支架
生物力学
应力
tibial fracture
external fixation
biomechanics
stress
