Minimum 5-year follow-up and radiologic analysis of the all-polyethylene tibial component of the Kinemax Plus system

All-polyethylene tibial components remain controversial. We report a series of 249 cemented Kinemax Plus total knee arthroplasties using an all-polyethylene tibial component. After a minimum of 5 years, the median Knee Society pain, Knee Society function, and Hospital for Special Surgery Scores were 89, 60, and 83.5 with 86% good or excellent results. The cumulative survival rate was 94.5% at 7 years. Of tibial components, 38% had a radiolucent line, but only 1% had significant radiolucencies. The presence of a radiolucent line did not affect Knee Society or Hospital for Special Surgery scores adversely. This series is comparable to other series using either an all-polyethylene or a metal-backed tibial component. There currently is no good evidence that the experimentally superior metal-backed tibial components offer any advantage in practice.