ABSTRACT
BACKGROUND: We aim to investigate using finite element model (FEM) whether the use of a cross-link is a risk factor for rod fracture at the pedicle subtraction osteotomy (PSO) site. METHODS: The geometry and dimensions of the FEM were obtained from a high-resolution computed tomography scan data of a 65â¯years old female patient with spinal sagittal imbalance. The intact model was modified to place PSO on the L4 spine. A cross-link was placed at the PSO site. A multisegment spinal fusion model from L1 to the pelvis was used to compare and analyze the peak von Mises stress (PVMS) values of the implants. A compressive follower load of 400â¯N was added to the validated intact lumbar spinal model in the follower load path direction. RESULTS: After PSO surgery, the PVMS of the rod was significantly increased during flexion and extension at the PSO site. With the cross-link at the PSO site, the PVMS of the rod was further significantly increased during flexion and extension. CONCLUSION: The cross-link at the PSO site increased the risk of rod facture, especially during flexion and extension stress.
