Publications & Reports

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Panel de la FDA Aprueba en Forma Unánime el Reemplazo Total de Disco

El 2 de junio de 2004, el panel para dispositivos ortopédicos y de rehabilitación de la Dirección de Alimentos y Fármacos de los Estados Unidos aprobó en forma unánime el primer reemplazo total de disco, sujeto a ciertas condiciones. Aunque en Europa el UHMWPE se ha utilizado desde la década de 1980 para reemplazos de discos en la columna vertebral, estos dispositivos sólo han estado disponibles en Estados Unidos para fines de investigación.

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Desarrollo de la prueba de perforación pequeña para el UHMWPE

Este capítulo de libro, disponible aquí con la autorización de Trans Tech Publications Ltd, revisa el desarrollo histórico de la prueba de perforación pequeña y las investigaciones recientes sobre métodos de prueba mecánicos con muestras en miniatura para caracterizar el UHMWPE utilizado en componentes ortopédicos.

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NMR Analysis of Copolymer Content and Branching in UHMWPE Resin

Samples of UHMWPE resin were analyzed using 1H NMR to quantify the co-polymer content and branching. The analysis was performed to assist the ASTM committee for F648 in identifying test methods suitable for characterizing the molecular structure of UHMWPE resin materials.

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Alpha-Tocopherol (Vitamin E) Doped Highly Crosslinked UHMWPE

Researchers from MGH in Boston have investigated highly crosslinked UHMWPE doped with alpha-Tocopherol (Vitamin E). The researchers observed that the biocompatible antioxidant improved the oxidation resistance, wear resistance, and fatigue resistance of 100kGy-irradiated, highly crosslinked UHMWPE.

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Effect of Joint Loading on Clinical Wear

In this clinical wear study, researchers from the University of Chicago investigated the effect of joint loading on the measurement of radiographic wear. Using the Martell computerized radiographic wear technique, 78 paired AP pelvis radiographs in 46 patients at a mean of 14 months after surgery (range 1-92 months) were evaluated with and without joint loading.

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Effects of Contact Area and Stress on Wear of UHMWPE

The effects of contact area and contact stress on the wear of ultrahigh molecular weight polyethylene articulating with a polished surface of cobalt-chromium alloy were evaluated using a pin-on-disk apparatus implementing bi-directional movement. Within a relevant range of contact stress, volumetric wear rate increased with increasing contact area.

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Rheology of Joint Fluid in Total Knee Arthroplasty Patients

While the properties of joint fluid may affect the tribology of joint replacement prostheses, the flow parameters of joint fluid have not yet been examined in the context of total knee arthroplasty (TKA). The objective of this study was to evaluate the flow properties of joint fluids in patients undergoing index TKA or revision TKA.

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NIH Draft Consensus Statement on Knee Replacement

The National Institutes of Health has published a Draft Consensus statement for total knee replacement (TKR) in the United States. This statement reflects the current scientific knowledge regarding TKR, as reviewed at a consensus development conference on Dec 8-10, 2003.

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Two-Year Clinical Results for Highly Crosslinked UHMWPE in THA

Researchers from the University of Chicago report the two-year results for a prospective randomized trial comparing highly crosslinked to standard polyethylene in total hip replacements. A significant reduction in two and three-dimensional linear wear rates (42 and 50 percent) was found in the highly crosslinked group.

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Fractography of UHMWPE Following Accelerated Aging

In this study, researchers from Zaragoza and Madrid have explored the fractography of molded GUR 1050 that was gamma sterilized in air and then followed by different aging times at 120 ºC. The microstructure of the UHMWPE from the oxidized zone of the specimens was similar to that found in gamma irradiated tibial components, which had been shelf-aged for 6-7 years.

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