[Ceramic-to-ceramic combination. Relic or renaissance?]
1Klinikum Grosshadern, Ludwig-Maximilians-Universität München.
Der Orthopade
|February 1, 1997
Abstract:
More than 20 years after the introduction of the alumina-alumina bearing system for total hip replacements (THRs) in Germany, this combination still only accounts for a small percentage of the conventional combinations with polyethylene cups. Follow-up examinations of ceramic-ceramic THRs with early alumina quality result in an extreme range of linear wear rates from 30 nm to 3.7 mm per year. Simulator tests confirm the potential for minimal debris generation but also show the sensitivity of the system to malpositioning and un-smooth repositioning.
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