一种颈椎椎间人工关节的构形及力学性能

目的 设计制作一种以切口弹簧为主体的颈椎椎间人工关节，并进行力学分析。方法 此种椎间人工关节由钛合金和超高分子高密度聚乙烯材料制成，包括笼箱和内核两部分。笼箱外形类似于椎间螺纹穿通融合器（TFC），上、下两面具有螺纹，在两侧有切口弹簧，内腔似扁橄榄形；内核亦似扁橄榄形，但较内腔略小。将内核打入笼箱内腔，通过切口弹簧的压缩和内核的微小滑动，以实现类似于前屈、后伸和侧屈的运动。将其置于MTS 858材料试验机上进行强度和疲劳实验。结果 强度试验结果显示：当施加压力为130N时，笼箱无损伤和断裂，弹簧压缩0.70mm，变形幅度未超过设计要求。抗疲劳强度：经过4天连续10万次应力循环作用后取下试件，观察试件未出现任何损伤。结论 此种人工关节可能成为一种性能良好的人工椎间盘假体。

THE STRUCTURAL DESIGN AND MECHANICAL ANALYSIS OF A NEW MANUAL INTERVERTEBRAL JOINT

Objective To design a type of intervertebral manual joint with grooving spring and analyse its mechnical analysis. Methods The joint consists of two parts: cage and internal nucleus. The cage with flat olive bore looks similar to the contour of the Ray-TFC, and has grooving spring on lateral sides. The internal nucleus also looks like flat olive in appearance but little smaller than the bore. After the insertion of the internal nucleus into the bore, the analogous motion of flexion, extension and lateral bending could be achieved through the stretching of the spring and the minute sliding of the nucleus. The intensity and fatigue tests then were carried out on MTS 858 machine. Results The results of intensity test proved that when the pressure reached to 130N, the cage still remained intact, and the spring was reduced 0.70mm . The fatigue test shew that there was no damage caused to the joint after 1×10 5 stress circulations in four days. Conclusion This type of manual joint may replace cervical disc well.