对寰枢椎侧块螺钉钛板固定装置的力学性能评价

目的：分析、评价寰枢椎侧块钉板装置的力学性能。为其临床应用提供生物力学理论依据。方法：通过有限单元法（FEM）的结构分析功能，建立寰枢椎侧块钉板装置的计算机模型。并根据钢板同定在椎体上的重力受压和前屈提托情况模拟加载。仿真分析模型各部分的应力、应变值及分布。结果：在模拟受压和提拉情况下。钢板的应力集中区位于钢板中部两侧，螺钉的应力集中区则位于置入椎体根部。结论：钢板中部两侧以及螺钉置入椎体根部容易产生应力疲劳．在临床应用时应注意采取预防措施。

Finite element analysis of atlantoaxial screws and plates instrument for upper cervical spine stability

Objective:To evaluate the biomechanical properties of atlantoaxial screws and plates instrument for upper cervical spine stability.Method:With the structure analysis function of Ansys 7.0,a model of atlantoaxial screws and plates complex endued with material properties was built.Under the same loading condition as short segment occipitocervical fixation plate(SSOFP)encountering in fatigue test,this model was restricted and loaded.Through structure analysis,the strain/stress distributions in it were processed.Result:The results show that several stress-bearing areas locate in the middle area of plate and the root of screw.Conclusion:The middle area of plate and the roots of screw are apt to develope load bearing and this should be considered thoroughly in the clinical application.