四种脊柱内固定器的生物力学评价

Biomechanical evaluation of the four kinds of internal fixation devices for the thoracolumber spine

目的 :评价四种短节段脊柱内固定器械的生物力学性能。方法 :取 2 4具猪胸腰段 (T1 0 ～ L5 )脊柱标本 ,模拟最严重前中柱损伤模型 ,通过测定加载方向应变和位移或角度值椎弓根螺钉抗拔出力值 ,比较短节段器械 CYL、Dick、AF、RF四种椎弓根内固定系统在轴向压缩、弯曲和扭转实验的生物力学稳定性及椎弓根螺钉握持能力。结果 :器械的稳定性及椎弓根螺钉直径、螺纹特点、螺钉固定装置等结构密切相关。结论 :CYL具有结构设计合理、稳定性较好 。

Objective:To make biomechanical evaluation of the four kinds of the internal fixation devices for the thoracolumber spine.Methods:Twenty four pig's thoracolumber spine were taken to imitate most severe injury of anterior two column instability. Biomechanical testings of stability were performed in axial compression,laterial bending and rotation by recording strain and displacement or angle on the loading side and axial extraction forces of each pedicle screw internal fixation systems:DICK,AF,RF,CYL.Results:The stability of instrumentation is correlated with structure such as the diameter of pedicle screws,the fixing device of screws and so on.Conclusion:Compared with DICK,AF,RF,the CYL fixation device has more reasonable structure and also achieved better stability. [FK(WB80011。6]