摘要目的 通过有限元法分析枕寰枢复合体前路减压(经口齿突切除术)和后路减压术的生物力学改变. 方法 以正常枕寰枢复合体模型为基础,建立几种前路减压、后路减压模型以及前路、后路减压手术模型,在屈曲载荷下,和正常模型对比分析运动学,关节应力和韧带应变. 结果 与正常模型比较,前路减压模型的寰枕、寰枢间运动角度、关节应力、韧带应变和前后移位都增大,寰枢角度变化更明显;后路减压模型的寰枕、寰枢间运动角度、关节应力、韧带应变和前后移位亦都增大,寰枕角度变化更明显. 结论 前后路减压手术均破坏了枕寰枢复合体的稳定性,且前路的稳定性更差,当寰枢正中关节已经受损时行单纯的后路减压而不行固定术危险性较大.

abstractsObjective To predict the alterations in biomechanical behaviors of decompression procedures including anterior and posterior ones in occipitoatlantoaxial complex.Methods Finite element models representing anterior decompression (e.g.odontoidectomy) and posterior decompression were evaluated by comparison the kinematics,joint loading,and strain in ligaments with normal conditions under flexion load.Results The ranges of motion,joint loading,strain in ligaments and anterior-posterior translation under flexion load of anterior decompression were increased both in C0-C 1 and C1-C2 levels; and the later was more significant.The range of motion,joint loading,strain in ligaments and anterior-posterior translation under flexion load of posterior decompression were increased both in C0-C1 and C1-C2 levels,and the former was more significant.Conclusion Both anterior and posterior decompression procedures can compromise the stability of occipitoatlantoaxial complex,and the alteration is more significant in the anterior procedure; posterior decompression without fusion is dangerous when the median atlantoaxial joints have already compromised.