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目的 比较直径2.0 mm与2.5 mm螺钉固定基于正常人群肘关节形态而完成的3D打印钛合金尺骨冠突假体的力学稳定性.方法 通过对正常骨性结构的成年受试者的肘关节进行CT扫描并行三维重建后设计尺骨冠突假体,分别模拟使用直径为2.0 mm及2.5 mm的螺钉进行固定.对屈肘30°、90°、130°下两种直径螺钉固定尺骨冠突假体的稳定性进行有限元分析并比较其等效应力峰值和假体最大位移量.结果 肘关节屈曲30°时,2.0 mm组螺钉与2.5 mm组螺钉的等效应力峰值分别为56.29 MPa及39.96 MPa,假体最大位移量分别为0.038 0 mm及0.029 0 mm;肘关节屈曲90°时,2.0mm组螺钉与2.5 mm组螺钉等效应力峰值分别为8.97 MPa及8.12 MPa,假体最大位移量分别为0.006 5 mm及0.005 8mm;肘关节屈曲130°时,2.0 mm组螺钉与2.5 mm组螺钉等效应力峰值分别为10.03 MPa及9.32 MPa,假体最大位移量分别为0.007 9 mm及0.006 6 mm.两种螺钉固定方式的最大等效应力均位于螺钉的顶帽与顶杆螺纹交界处,直径2.5 mm螺钉的等效应力峰值在同一屈曲角度时较2.0 mm螺钉低;在尺骨冠突假体位移方面,不论何种屈曲角度,2.5 mm螺钉固定的假体位移量均较2.0 mm螺钉小.结论 直径2.5 mm螺钉较2.0 mm螺钉固定3D打印钛合金尺骨冠突假体固定更稳定.“,”Objective To compare difference in stability between two fixation modes in application of three-dimensional (3D) printed coronoid process prosthesis.Methods 3D coronoid process prosthesis was reconstructed from computed tomography (CT) scanning acquired from volunteers with normal bony architecture of elbow.The prosthesis fixation was simulated using screws with diameter of 2.0 mm and 2.5 mm separately.Finite element analysis (FEA) was conducted at elbow flexion with different angles and the parameters including the maximum equivalent stress and the maximum displacement were evaluated.Results Compared fixation using screw with the diameter of 2.0 mm and 2.5 mm,the maximum equivalent stress were 56.29 MPa and 39.96 MPa and the maximum displacement were 0.038 0 mm and 0.029 0 mm in 30° flexion of elbow;the maximum equivalent stress were 8.97 MPa and 8.12 MPa and the maximum displacement were 0.006 5 mm and 0.005 8 mm in 90° flexion of elbow;the maximum equivalent stress were 10.03 MPa and 9.32 MPa and the maximum displacement were 0.007 9 mm and 0.006 6 mm in 130° flexion of elbow.The maximum equivalent stress occurs at the junction of head and shaft with in both situations while the value from screw with diameter of 2.5 mm was lower.The displacement was smaller in the screw with diameter of 2.5 mm.Conclusion Compared to screws with the diameter of 2 mm,screw with the diameter of 2.5 mm shows superior stability in the fixation of 3D printed coronoid process prosthesis.