Biomechanical Investigation of the Posterior Pedicle Screw Fixation System at Level L4-L5 Lumbar Segment with Traditional and Cortical Trajectories: A Finite Element Study

Figure 1

Finite-element model of the lumber vertebra and diagrams illustrating the trajectory from the axial and sagittal views. (a) TT screws at the cranial and caudal levels (TT-TT); (b) CBT screws at the cranial and caudal levels (CBT-CBT); (c) CBT screws at the cranial level and TT screws at the caudal level (CBT-TT); (d) TT screws at the cranial level and CBT screws at the caudal level (TT-CBT); (e)–(h) are the axial and sagittal views of each respective technique of (a)–(d).

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