Finite element analysis of stability of ulnar coronoid process prosthesis using 2.0 mm and 2.5 mm screws fixation / 中华骨科杂志

ABSTRACT

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.