【摘要】 目的比较双节段腰椎前路椎间融合术(ALIF)不同后路内固定对邻近节段退变的影响。方法建立L1~5运动节段正常有限元模型,根据正常模型分别建立L3~4与L4~5双节段前路腰椎椎间融合并行后路椎弓根螺钉固定与经椎板关节突螺钉固定两个模型。对各模型分别施以265N轴向压缩载荷与10 Nm前屈、后伸、侧弯与扭转力矩,计算L2~3运动节段椎间盘髓核内压与椎间运动范围。结果正常模型L2~3运动节段在前屈、后伸、侧弯与扭转运动状态下,椎间盘髓核内压与椎间运动范围均最小;同经椎板关节突螺钉模型相比,椎弓根螺钉固定模型髓核内压在前屈、后伸、侧弯与扭转运动状态下分别增加14.8%、15.2%、8%与8.7%,而椎间运动范围分别增加9.8%、7.3%、9.3%与8.3%。结论双节段腰椎前路椎间融合辅以椎弓根螺钉固定比经椎板关节突螺钉固定更易导致邻近节段退变。更多还原

【Abstract】 Objective To compare the influence of different posterior fixations of two- level anterior lumbar interbody fusion( ALIF) on adjacent segmental degeneration. Methods A normal finite element model of L1 ~ 5 was developed,two two- level ALIF models augmented with translaminar facet screws or pedicle screws were developed based on the normal model. A 265 N compressive loading together with 10 Nm moment of flexion,extension,lateral bending and axial rotation was imposed on each model and the range of motion and nucleus pressure of L2 ~ 3 were compared in the three models. Results The normal models were with the lowest nucleus pressure and range of motion in L2 ~ 3 when compared with the models augmented with pedicle screws or translaminar facet screws.In addition,compared with the model augmented with translaminar facet screws,nucleus pressure increased 14. 8%,15. 2%,8%and 8. 7%,and range of motion increased 9. 8%,7. 3%,9. 3% and 8. 3% in the model augmented with pedicle screws in flexion,extension,lateral bending and axial rotation,respectively. Conclusion A two- level ALIF augmented with pedicle screws may result in more severe adjacent segmental degeneration.更多还原