2022, Vol. 26 ›› Issue (12): 1866-1871
Three-dimensional finite element analysis of anterior cervical fixation system in children
Occipito-atlanto-axial joint has its own characteristics in morphological development and physiological characteristics, and clinical injuries are common in children. The differences between the biomechanical characteristics of occipito-atlantoaxial internal fixation (a way to maintain the stability of the atlantoaxial spine) and conventional fusion need further study.
To evaluate the biomechanics of a new occipitocervical anterior internal fixation device in children by three-dimensional finite element analysis.
The transverse ligament and joint capsule were deleted on the basis of the established three-dimensional finite element model of the normal C0-C2 joint, and the occipitocervical injury model was simulated. A new type of anterior occipitocervical internal fixation device was placed on the model to construct the finite element model of internal fixation. The motion range and stress of each model were compared and analyzed by the finite element method.
Compared with the normal children’s finite element model of occipitocervical titanium plate-screw internal fixation, the occipitocervical and atlantoaxial motion was significantly limited in flexion and extension, lateral flexion and rotation, indicating that this occipitocervical internal fixation system could achieve better stability. During the flexion, extension, lateral flexion and rotation of the occipito-atlantoaxial structure, the stress mainly concentrated on the contact between the titanium plate and the slope, the axial vertebral body, and the contact between the screw and the bone surface. The maximum stress originated from the contact between the screw and the titanium plate, indicating that the stress of the occipitocervical internal fixation system was relatively dispersed, which reduced the risk of screw-titanium plate fracture.
occipito-atlantoaxial, internal fixation, finite element, children, motion range, stress