可吸收颈椎椎间融合器的生物力学分析

Biomechanical Analysis of Absorbable Anatomical Design Fusion Cage

目的观察不同材料、不同形状的颈椎椎间融合器(cervical fusion cage,CFC)的初始稳定性及拔出力。方法采集40具新鲜尸体颈椎标本,分为5组:正常对照组(N)、自体髂骨组(L)、InterFix组、解剖型同种异体皮质骨椎间融合器(allograft fusion cage,AFC)组、可吸收椎间融合器(absorbable design fusion cage,ADFC)组。制作成颈椎融合标本,采用实验应力分析方法,分别测试不同CFC椎间融合的轴向刚度及拔出力。结果InterFix轴向刚度最高;ADFC的轴向刚度与AFC相比,无显著性差异(P>0.05);拔出力以InterFix最大,ADFC、AFC拔出力也较大,它们之间具有显著性差异(P<0.05)。结论ADFC刚度低、拔出力大,是理想的CFC。

Objective To investigate the initial stability and pull out force of cages with various material and shape. Methods Cervical fusion specimens were made using forty fresh cadavers. The specimens were classified into 5 groups, ie, the control group, auto iliac crest group, InterFix group, allograft fusion cage（AFC） group, and absorbable design fusion cage（ADFC） group. The axial stiffness and pull out forces of various cages were analysed by stress-analysis method. Results Of the five cages, the axial stiffness of InterFix is the highest, the axial stiffness of ADFC is similar to that of AFC（P 〉0.05）. InterFix has the largest pullout strength, and that of ADFC and AFC is also large . There is significant difference among them （P 〈 0.05）. Conclusion ADFC is an ideal fusion cage with its low axial stiffness and larger pull out force.