寰椎枕骨化畸形对寰枢关节运动影响的实验研究

目的用生物力学测试人类寰椎枕骨化模型,阐明此模型对寰枢关节三维运动的影响.方法采用新鲜人体枕颈部标本制作寰椎枕骨化畸形实验模型,用生物力学测试,确定寰枢关节的运动参数,作统计学分析.结果与标本比较,模型的寰枢关节屈曲运动的中性区变化不明显,弹性区和运动范围明显增大(P＜0.05),旋转运动的中性区和运动范围明显增大(P＜0.05),后伸和侧曲运动各运动参数和旋转运动的弹性区相差不显著.结论(1)寰椎枕骨化畸形造成枕寰关节运动丧失,寰枢关节的负荷和旋转不稳定趋势增加,易导致寰椎横韧带退变、松弛和寰枢关节不稳.(2)建议对寰椎枕骨化畸形的患者密切观察,证实寰枢关节临床不稳,尽早手术融合.

The Motion Changes of Atlantoaxial Joint Influenced by the Occipitalization of the Atlas: An Experiment Study

Objective:Biomechanical tests were done on the occipitalization model to clarify the three dimension movement changes of atlanto-axial joint caused by the occipitalization of the atlas.Methods:The biomechanical test models of occipitalization of the atlas were made on fresh human cadaveric specimens containing occipital-cervical region.Biomechanical tests were done on the normal specimens and pathological models respectively.Motion parameters of atlanto-axial joint were measured and statistical analysis were done.Results:In comparison of the motion of atlanto-axial joint between the normal specimens and pathological models.The EZ(Elastic zone)and RM(Range of motion)beyond the flexion motion increased significantly(P<0.05)in pathological models,and NZ(Neutral zone)and RM beyond rotation motion increased significantly(P<0.05)too.The differences of other parameters between normal and pathological specimens were not significant.Conclusion:1.Occipitalization of the atlas results in complete lost of the motion of occipito-atlantal joint,increase of the load and the tendency of the rotation instability in atlanto-axial joint.It may lead to the degenerative change and laxity of the transverse ligament of the atlas and instability of atlanto-axial joint.2.It suggested that the patients with occipitalization of the atlas should be followed up closely at regular intervals.When clinical instability of the atlanto-axial joint is found,fusion operation should be done as soon as possible.