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目的:比较颈椎前路记忆加压固定器与钛板对颈椎前路椎间盘切除融合术后邻近节段椎间盘活动度及应力的影响。方法:有偿募集1名成年男性志愿者，排除颈椎畸形、骨折、感染等疾病后，行Cn 3~Cn 7薄层CT扫描。将扫描数据导入三维有限元建模软件，建立生理状态下的完整三维有限元模型并验证其有效性。将Cn 5-6椎间盘切除后置入椎间融合器，前方应用钛板或颈椎前路记忆加压固定器辅助固定，从而建立钛板固定和记忆加压固定器固定的三椎有限元模型。将三种模型导入三维有限元分析软件ANSYS 16.0，加载垂直向下的轴向73.6 N载荷模拟头重及1. 0 N·m的扭矩模拟颈椎前屈、背伸、左侧弯、右侧弯、左旋转、右旋转六种运动，比较完整模型、钛板固定与记忆加压固定器固定后相邻节段椎间盘活动度和应力变化。n 结果:所建立的三维有限元模型在六种工况下的椎间盘活动度与既往研究结果基本相似，证明模型有效。在相邻Cn 4，5节段前屈、后伸，左、右侧屈及左、右旋转六种工况活动度分别为：完整模型3.9°、4.2°、3.7°、3.7°、2.2°和2.2°，钛板固定4.6°、4.7°、4.3°、4.4°、3.3°和3.1°，记忆加压固定器固定4.4°、4.3°、4.0°、4.2°、2.8°和2.7°；不同工况下椎间盘的最大应力分别为：完整模型1.81、1.60、3.99、2.06、3.63和3.41 MPa，钛板固定1.86、1.67、4.21、2.16、3.82和3.63 MPa，记忆加压固定器固定1.84、1.64、4.17、2.14、3.78和3.58 MPa。在相邻Cn 6，7节段六种工况活动度分别为：完整模型3.1°、3.2°、2.5°、2.5°、1.2°和1.3°，钛板固定4.2°、3.7°、3.4°、3.0°、2.1°和2.2°，记忆加压固定器固定3.5°、3.3°、2.5°、2.7°、1.8°和1.9°；不同工况下椎间盘的最大应力分别为:完整模型0.45、0.66、1.12、0.85、0.84和0.82 MPa，钛板固定0.62、0.93、1.55、1.24、1.44和1.27 MPa，记忆加压固定器固定0.61、0.92、1.54、1.22、1.07和1.24 MPa。钛板固定术后相邻节段各个方向活动度及椎间盘压力均高于记忆加压固定器固定。n 结论:颈椎前路记忆加压固定器较钛板固定对相邻节段椎间盘的活动度及应力影响较小，一定程度上可减缓相邻节段退变的进程。“,”Objective:To compare the effect of the new anterior cervical spine memory compression fixation device (GYZ memory alloy plate) and traditional titanium plate on the range of motion (ROM) and stress of the adjacent segment after anterior cervical discectomy and fusion.Methods:An adult male volunteer was recruited for a fee. After excluding cervical malformations, fractures, infections and other diseases, Cn 3-Cn 7 thin-layer CT scans were performed. Import the scanned data into the finite element modeling software to establish the finite element model of the physiological group and verify itseffectiveness. After Cn 5,6 discectomy, the intervertebral fusion device was inserted, and the anterior fixation was assisted by a conventional titanium plate or a new type of fixator. Thus, the finite element model of the traditional titanium plate group and the new fixer group was established. The three models were imported into the finite element analysis software ANSYS 16.0, and a vertical downward axial load of 73.6 N was loaded to simulate the head weight and the torque of 1.0 N·m to simulate the cervical spine flexion, extension, left lateral bending, right lateral bending, left rotation and right rotation.Compare the changes of intervertebral disc ROM and stress in adjacent segments of physiological group, traditional titanium plate group and new type fixator group.n Results:The intervertebral disc ROM under six conditions was basically similar to the results of previous studies, and the model was effective. In the adjacent segment Cn 4,5, the three groups of activities in the flexion, extension, left lateral bending, right lateral bending, left rotation and right rotation conditions were: physiological group 3.9°, 4.2°, 3.7°, 3.7°, 2.2° and 2.2°, traditional titanium plate group 4.6°, 4.7°, 4.3°, 4.4°, 3.3° and 3.1°, and new fixture group 4.4°, 4.3°, 4.0°, 4.2°, 2.8° and 2.7°. The maximum stresses of the intervertebral discs under three different working conditions were: physiological group 1.81, 1.60, 3.99, 2.06, 3.63 and 3.41 MPa, traditional titanium plate group 1.86, 1.67, 4.21, 2.16, 3.82 and 3.63 MPa, and new fixture group 1.84, 1.64, 4.17, 2.14, 3.78 and 3.58 MPa. In the adjacent segment Cn 6,7, the activities of the three groups in six working conditions were: physiological group 3.1°, 3.2°, 2.5°, 2.5°, 1.2° and 1.3°, traditional titanium plate group 4.2°, 3.7°, 3.4°, 3.0°, 2.1° and 2.2°, and new fixture group 3.5°, 3.3°, 2.5°, 2.7°, 1.8° and 1.9°.The maximum stress of the intervertebral disc under three different working conditions was: physiological group 0.45, 0.66, 1.12, 0.85, 0.84 and 0.82 MPa, traditional titanium plate group 0.62, 0.93, 1.55, 1.24, 1.44 and 1.27 MPa, and new fixture group 0.61, 0.92, 1.54, 1.22, 1.07 and 1.24 MPa. The ROM and disc pressure of adjacent segments in the conventional titanium plate group were higher than those of the new fixator group.n Conclusion:Compared with the traditional titanium plate, the new type of anterior cervical memory compression fixator has less effect on the ROM and stress of adjacent segments, which may slow down the process of adjacent segments degeneration to a certain extent.