股骨转子间骨折双头自动加压新型外固定支架固定的生物力学研究

Biomechanical study of new type two-head automatic pressure external fixator(TAPEF) for the treatment of intertrochanteric fracture

目的:从生物力学角度探讨双头自动加压新型外固定支架的力学特性。方法:将15具新鲜湿润股骨头标本,分试验组5具和对照组10具(动力髋螺钉DHS和传统外固定支架各5具)。在试验时实行等级加载,0～1800N,加载速度1.4mn/min,分别测量股骨转子间骨折固定后的强度和刚度、扭转力学性能和股骨的极限承载能力,以比较不同器械的优劣。结果:试验组在股骨转子间固定后的强度和刚度,股骨的扭转力学性能以及极限承载能力均优于DHS和传统外固定支架(P<0.05)。结论:双头自动加压新型外固定支架嵌后比较紧密,无滑动,能有效地防止髋内翻畸形的发生。

Objective：To investigate the mechanical characteristics of new type two-head automatic pressure external fix- ator in the view of biomechanics. Methods：Fifteen fresh and humid specimens were selected and divided into experimental group （5 cases） and control group （10 cases）. The control group were respectively applied with DHS （5 cases） and traditional external fixator （5 cases）. In order to compare the different apparatus, the strength, stiffness and twist mechanical function of femoral intertrochanteric fracture with different device were measured respectively when the specimens were under the pressure of 0-1 800 N and loading speed 1.4 mn/min. Results：The strength,stiffness,twist mechanical function and maximum endurance of femora in the experimental group were obviously superior than that of DHS and traditional external fixator （P〈0.05）. Conclusion：Two head automatic new type pressure external fixator can embed more tightly without sliding,also can prevent the occurrence of coxa vara effectively.