Overall , there was a notable enhancement of joint function after the procedure , with a satisfactory mid- and long-term survival of the ceramic components , which is comparable to that of the conventional alloy components reported previously .
However , revision due to aseptic loosening , wear , and component fracture appeared to be rare , demonstrating the safety of in vivo use of ceramic bearings in the TKA procedure .
Conclusions Ceramic TKA implants show similar post-operative clinical results and survival rate compared to their conventional metallic counterparts .
Our results confirmed the safety of in vivo use of ceramic bearings in TKA , with rare implant breakage and aseptic loosening .
Purpose Ceramic bearings have been widely used in total hip arthroplasty ( THA ) , which result ed in satisfactory clinical outcomes due to the excellent tribological characteristics of the implants .
However , ceramic components are not commonly used in total knee arthroplasty ( TKA ) because of brittleness .
This study aim ed to gather and analyze information regarding the clinical outcomes ( including survival without revision , causes of revision , functional outcome , and incidence of loosening ) and reach a definitive conclusion about the use of ceramic femoral components in total knee arthroplasty .
What Can Be Learned From Minimum 20-year Followup Studies of Knee Arthroplasty?
Background Long-term evaluation of knee arthroplasty should provide relevant information concerning the durability and performance of the implant and the procedure . Because most arthroplasties are performed in older patients , most long-term followup studies have been performed in elderly cohorts and have had low patient survivorship to final followup ; the degree to which attrition from patient deaths over time in these studies might influence their results has been poorly characterized . Questions / purpose sThe purpose of this study was to examine the results at 20-year followup of two prospect ively followed knee arthroplasty cohorts to determine the following : ( 1 ) Are there relevant differences among the two implant cohorts in terms of revision for aseptic causes ( osteolysis , or loosening ) ? ( 2 ) How does patient death over the long followup interval influence the comparison , and do the comparisons remain valid despite the high attrition rates ? Methods Two knee arthroplasty cohorts from a single orthopaedic practice were evaluated : a modular tibial tray ( 101 knees ) and a rotating platform ( 119 knees ) design . All patients were followed for a minimum of 20 years or until death ( mean , 14.1 years ; SD 5.0 years ) . Average age at surgery for both cohorts was > 70 years . The indications for the two cohorts were identical ( functionally limiting knee pain ) and was surgeon-specific ( each surgeon performed all surgeries in that cohort ) . Revision rates through a competing risks analysis for implants and survivorship curves for patients were evaluated . Results Both of these elderly cohorts showed excellent implant survivorship at 20 years followup with only small differences in revision rates ( 6 % revision versus 0 % revision for the modular tibial tray and rotating platform , respectively ) . However , attrition from patient deaths was substantial and overall patient survivorship to 20-year followup was only 26 % . Patient survivorship was significantly higher in patients < 65 years of age in both cohorts ( 54 % versus 15 % , p < 0.001 modular tray cohort , and 52 % versus 26 % , p = 0.002 rotating platform cohort ) . Furthermore , in the modular tray cohort , patients < 65 years had significantly higher revision rates ( 15 % versus 3 % , p = 0.0019 ) . Conclusions These two cohorts demonstrate the durability of knee arthroplasty in older patients ( the vast majority older than 65 years ) . Unfortunately , few patients lived to 20-year followup , thus introducing bias into the analysis . These data may be useful as a reference for the design of future prospect i ve studies , and consideration should be given to enrolling younger patients to have robust numbers of living patients  at long-term followup . Level of Evidence Level III , therapeutic study . See Guidelines for Authors for a complete description of levels of evidence
Overall , there was a notable enhancement of joint function after the procedure , with a satisfactory mid- and long-term survival of the ceramic components , which is comparable to that of the conventional alloy components reported previously .
However , revision due to aseptic loosening , wear , and component fracture appeared to be rare , demonstrating the safety of in vivo use of ceramic bearings in the TKA procedure .
Conclusions Ceramic TKA implants show similar post-operative clinical results and survival rate compared to their conventional metallic counterparts .
Our results confirmed the safety of in vivo use of ceramic bearings in TKA , with rare implant breakage and aseptic loosening .
Purpose Ceramic bearings have been widely used in total hip arthroplasty ( THA ) , which result ed in satisfactory clinical outcomes due to the excellent tribological characteristics of the implants .
However , ceramic components are not commonly used in total knee arthroplasty ( TKA ) because of brittleness .
This study aim ed to gather and analyze information regarding the clinical outcomes ( including survival without revision , causes of revision , functional outcome , and incidence of loosening ) and reach a definitive conclusion about the use of ceramic femoral components in total knee arthroplasty .