Publications by authors named "Megan L Harper"

Purpose: We evaluated the consequences of cobalt-chromium alloy (CoCr) wear debris challenge in the peri-spine region to determine the inflammation and toxicity associated with submicron particulates of CoCr-alloy and nickel on the peri-spine.

Methods: The lumbar epidural spaces of (n = 50) New Zealand white rabbits were challenged with: 2.5 mg CoCr, 5.

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Background: Cervical disc arthroplasty is regarded as a promising treatment for myelopathy and radiculopathy as an alternative to cervical spine fusion. On the basis of 2-year clinical data for the PRESTIGE(®) Cervical Disc (Medtronic, Memphis, Tennessee), the Food and Drug Administration recommended conditional approval in September 2006 and final approval in July 2007; however, relatively little is known about its wear and damage modes in vivo. The main objective was to analyze the tribological findings of the PRESTIGE(®) Cervical Disc.

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For nearly 500 years, scholars have argued about the origin and antiquity of syphilis. Did Columbus bring the disease from the New World to the Old World? Or did syphilis exist in the Old World before 1493? Here, we evaluate all 54 published reports of pre-Columbian, Old World treponemal disease using a standardized, systematic approach. The certainty of diagnosis and dating of each case is considered, and novel information pertinent to the dating of these cases, including radiocarbon dates, is presented.

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The biological effect of wear of articulating surfaces is a continued concern with large joint replacements and, likewise, of interest for total disc replacements. There are a number of important biotribological testing parameters that can greatly affect the outcome of a wear study in addition to the implant design and material selection. The current ASTM and ISO wear testing standards/guides for spine arthroplasty leave many choices as testing parameters.

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