Biomechanical Analysis of Lumbar Fusion Cage Fixation Through Intervertebral Foramen

At present, the incidence of lumbar degenerative diseases is high. Transforaminal lumbar interbody fusion (TLIF) has become a commonly used treatment method in clinical practice. Different lumbar fusion devices will cause different mechanical responses in the internal fixation system and the lumbar spine. In order to explore the optimal structure of transforaminal lumbar interbody fusion cage, two kinds of transforaminal lumbar interbody fusion (TLIF) cage models, which are fusion device 1 and adjustable-angle fusion device were established. With the two cage models, the biomechanical analysis of fusion internal fixation in the lumbar L3-4 segment was carried out, and the overall range of motion of the model, the range of motion of the fusion segment, the maximum Von-Mises stress of the fusion device, the maximum Von-Mises stress of the internal fixation system, and the maximum Von-Mises stress of the L3 lower end plate and L4 upper end plate under six physiological activities (including flexion, extension, lateral bending, and axial rotation) were obtained. The results of this finite element analysis were compared with the literature results. Through the comparison, it was found that the adjustable-angle fusion device selected in this study had a significant effect in reducing the maximum Von-Mises stress on the Cage and the internal fixation system under six conditions. The adjustable-angle fusion device is a superior fusion device.