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An Anesthesia, Surgery, and Harvest Method for the Evaluation of Transpedicular Screws Using an In Vivo Porcine Lumbar Spine Model
Published on: May 31, 2017
Triangulated pedicle screw construct technique and pull-out strength of conical and cylindrical screws
1Department of Orthopaedics and Rehabilitation, University of Miami School of Medicine, Miami, Florida, USA.
Abstract:
To compare the mechanical effectiveness of a new conical screw design with a conventional cylindrical screw design, the screw insertion time, torque, and pull-out strength of single-pedicle screw and triangulated-pedicle screw constructs of each type of screw were compared in human cadaveric vertebral bodies. The time required to insert the conical screws was less than that required for cylindrical screws. Regression analysis revealed a positive correlation between insertion torque and pull-out strength of single and triangulated constructs of each type of screw. The conical screw had a greater increase than the cylindrical screw in the pull-out strength of triangulated pedicle screw constructs. Application of the new conical screw design was significantly faster, and the new screw had better mechanical fixation to the vertebral body than did the conventional cylindrical screw tested.
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