目的　建立L3~5有效的三维有限元模型，研究解剖型纳米羟基磷灰石/聚酰胺66椎间融合器在XLIF/OLIF手术中的生物力学属性。   方法　建立正常人L3~5有限元模型，模拟XLIF/OLIF手术过程分别装配子弹头cage和新型解剖型cage，并对模型进行赋值得到最终有限元模型。对模型施加400 N 的轴向压缩及8 Nm 力矩的预载荷，使模型产生前屈、后伸、侧弯、旋转运动，分析两种cage的最大应力值和应力分布情况，以及两组L4-L5椎体活动度。   结果　在6种不同工况下，子弹头cage的最大应力值分别为134.83、79.17、71.31、114.96、76.85、78.77 MPa，解剖型cage最大应力值分别为56.91、61.78、35.82、52.28、31.76、32.45 MPa，解剖型cage比子弹头cage的应力分布要小且分散；两组L4-L5椎体活动度均明显小于正常人活动度，且解剖型cage组活动度要小于子弹头cage组。   结论　在腰椎XLIF/OLIF微创手术中应用新型解剖型纳米羟基磷灰石/聚酰胺66椎间融合器可以降低最大应力值，避免应力集中，减少椎体活动度，具有较好的生物力学性能。

Objective　To establish an effective L3~5 three-dimensional finite element model, and study the biomechanical attributes of the anatomical nano-hydroxyapatite / polyamide 66 cage in XLIF/OLIF operation.　Methods　We established the model of normal lumbar spine( L3~5) in order to simulate the XLIF/OLIF operation process by assembling a new anatomic cage and a bullet- liked cage, and the assignment model was imported into software to obtain the final finite element model. Pre-load with axial compression of 400 N and 8 Nm torque was imposed on the model, which caused motion of flexion, extension, bending and rotation of the model. the maximum stress, stress distribution of the two kinds of cage and the ROM of the L4~L5 were analyzed.　Results　Under 6 different operating conditions, the maximum stress of the bullet-liked cage was 134.83, 79.17, 71.31, 114.96, 76.85, 78.77 MPa, and the maximum stress of the anatomic cage was 56.91, 61.78, 35.82, 52.28, 31.76, and 32.45 MPa, respectively. The stress distribution of anatomic cage was smaller and more dispersed than that of the bullet-liked cage. The ROM of L4~L5 in the two groups was significantly less than that of the normal persons，and the ROM of L4~L5 in anatomic cage group was less than that of the bullet-liked cage group.　Conclusions 　The application of the new anatomic nano-hydroxyapatite / polyamide 66 cage in minimally invasive XLIF/OLIF operation can reduce the maximum stress, circumvent the stress concentration and reduce the activity of vertebral body, proving that it has better mechanical properties.