1. Biomechanical Comparison of Corticopedicular Spine Fixation versus Pedicle Screw Fixation in a Lumbar Degenerative Spondylolisthesis Finite Element Analysis Model.
- Author
-
Farooqi AS, Narayanan R, Canseco JA, and Vaccaro AR
- Subjects
- Humans, Biomechanical Phenomena physiology, Range of Motion, Articular physiology, Finite Element Analysis, Pedicle Screws, Spondylolisthesis surgery, Lumbar Vertebrae surgery, Spinal Fusion methods, Spinal Fusion instrumentation, Laminectomy methods
- Abstract
Objective: To compare the stability of a corticopedicular posterior fixation (CPPF) device with traditional pedicle screws for decompression and fusion in adult degenerative lumbar spondylolisthesis., Methods: Finite element analysis (FEA) was used in a validated model of grade 1 L4-L5 spondylolisthesis to compare segmental stability after laminectomy alone, laminectomy with pedicle screw fixation, or laminectomy with CPPF device fixation. A 500-N follower load was applied to the model and different functional movements were simulated by applying a 7.5-Nm force in different directions. Outcomes included degrees of motion, tensile forces experienced in the CPPF device, and stresses in surrounding cortical bone., Results: At maximum loading, laminectomy alone demonstrated a 1
° increase in flexion range of motion, from 6.35° to 7.39° . Laminectomy with pedicle screw fixation and CPPF device fixation both reduced spinal segmental motion to ≤1° at maximum loading in all ranges of motion, including flexion (0.94° and 1.09° ), extension (-0.85° and -1.08° ), lateral bending (-0.56° and -0.96° ), and torsion (0.63° and 0.91° ), respectively. There was no significant difference in segmental stability between pedicle screw fixation and CPPF device fixation during maximum loading, with a difference of ≤0.4° in any range of motion. Tensile forces in the CPPF device remained ≤51% the ultimate load to failure (487 N) and stress in surrounding cortical bone remained ≤84% the ultimate stress of cortical bone (125.4 MPa) during maximum loading., Conclusions: CPFF fixation demonstrated similar segmental stability to traditional pedicle screw fixation whereas tensile forces and stress in surrounding cortical bone remained below the load to failure., (Copyright © 2024 Elsevier Inc. All rights reserved.)- Published
- 2024
- Full Text
- View/download PDF