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Design And Development Of A Novel Expanding Pedicle Screw For Use In The Osteoporotic Lumbar Spine, Parham Rasoulinejad

Electronic Thesis and Dissertation Repository

Pedicle screws are commonly utilized in spinal surgery; however, traditional designs often do not provide adequate fixation in osteoporotic spines. The objective of this thesis was to develop a novel expanding screw for use in osteoporotic lumbar pedicles. Helical screws capable of expanding post insertion were built on a rapid prototype machine. A materials testing machine performed axial load to failure tests in both Sawbones and cadaveric specimens comparing the new design to traditional screws (rate = 10mm/min to 20 mm). Output parameters included yield load, ultimate load, stiffness, energy to failure and total energy. The expanding screw showed a …