颈椎自张式记忆合金椎间融合器的生物力学初步研究

Biomechanical evaluation of Ni-Ti shape memory expansion mesh cage

目的设计制作颈椎自张式记忆合金椎间融合器,并对其进行生物力学性能评价。方法以6具新鲜人尸颈椎标本为实验对象,分为空白对照(N组)、颈椎自张式记忆合金椎间融合器(A组)和钛网(B组),A、B组附加颈前路钢板。分别测定轴向刚度、扭转刚度、颈椎整体运动范围等指标。结果轴向刚度值由小到大依次为N组、B组、A组(P>0.05);扭转刚度由低到高分别为B组、A组、N组(P<0.05);A组与N组相比,后伸、旋转位ROM较大,而前屈、侧屈位ROM较小(P>0.05)。结论使用颈椎自张式记忆合金椎间融合器可满足颈椎减压植骨术后即刻生物力学稳定性要求。

Objective To evaluate the biomechanical stability of Ni-Ti shape memory expansion mesh cage. Methods Total 6 fresh adult cervical specimens were studied. The axial-rigidity, twist-rigidity and three-dimentional motion of the C4-C6 segment were measured under the normal condition（N group）, Ni-Ti shape memory expansion mesh cage （A group）and cervical titanium mesh cage （B group）. Anterior self-lock plates were used in A and B groups. Results The axial-stiffness of A group was bigger than N group and B group（P〉0.05）. The Torsional-stiffness of A group was bigger than B group but smaller than N group （P〈0.05） .The range of motion during flexion, left/right bending of A group were smaller than that of N group, but the range of motion during extension and rotation of A group were bigger than that of N group（P〉0.05）. Conclusion Ni-Ti shape memory expansion mesh cage supplemented with anterior self-lock plates can provide adequate biomechanical stability of cervical spine.