腰骶前路内固定系统稳定性的生物力学评价

Biomechanical Evaluation on the Stability of Lumbosacral Anterior Instrumentation

目的:探讨腰骶前路的内固定方法,评价其生物力学稳定性。方法:制备24具新鲜成人尸体正常L3～S3节段脊柱标本,切除L5～S1椎间盘制成损伤模型,测试并比较脊柱L5～S1节段在正常、损伤、四种腰骶前路钛板螺钉固定、疲劳实验四种情况下的三维运动幅度。结果:四种内固定系统固定及疲劳实验后,L5～S1节段在各个方向的运动范围均比正常状态的运动范围小(P<0.05),梯形钛板螺钉在前屈、后伸及左、右弯方向上,均较其它组具有更好的稳定性。结论:四种腰骶前路内固定系统具有良好的即刻稳定性和抗疲劳稳定性,其中梯形钛板螺钉生物力学的稳定性能最佳。

Objective：To study the methods of lumbosacral anterior internal fixation and evaluate its biomechanical stability. Methods： To prepare the specimen of L3 - S3 vertebral column from 24 fresh adult cadavers. The models simulating damage were established by cutting the intervertebral disks of L5 - S1. The ranges of movement （ROM） in three dimensions of the L3 - S3 specimens were detected respectively in the conditions of normal, injured, fatigued and four kinds of lumbosaeral anterior internal fixation. The findings were compared. Results ： The ROM of L5 - S1 in coherent direction after four kinds of lumbosaeral anterior internal fixation or fatigue experiment were less than that in normal state （P 〈 0.05 ）. In the directions of flexion, extention, bend, the system of internal fixation with the ladder - shaped titanium screw showed better stability than other groups. Conclusion：Four kinds of lumbosacral anterior internal fixation have good instant stability and resistance to fatigue, in which the fixation with the ladder - shaped titanium screw has the best stability.