The objective of the current study was to develop an in vitro testing protocol to evaluate semi-rigid pedicle screw devices. A corpectomy model protocol exists to evaluate rigid spinal implants; however, semi-rigid devices are contraindicated for this condition. This paper describes a technique that simulates more closely the conditions a semi-rigid device would see in vivo. Finally, the new testing protocol is used to evaluate the DDS® pedicle screw-cable system. Benefits and shortcomings of the new protocol are discussed.

Issue Section:
Technical Brief
Topics:
Spinal pedicle screws, Testing, Cables, Screws, Spinal implants
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 by The American Society of Mechanical Engineers
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