In vivo roughening of retrieved total knee arthroplasty femoral components

BackgroundJoint registry data highlights the higher rates of cumulative revision for younger patients undergoing TKR. One of the reasons associated with this higher revision rate may be due to the wear of the UHMWPE leading to loosening. Alternate bearing surfaces have been developed to address this problem; however, roughening of the metal bearing surface has not been demonstrated in vivo.MethodWe recorded roughness measurements of retrieved femoral components.ResultsAverage lateral condyle roughness was 0.032 μm, compared to control values of 0.020 μm, p = 0.002; average medial condyle roughness was 0.028 μm, compared to a control value of 0.019, p < 0.001.ConclusionThere was a small but statistically significant roughening of femoral components in vivo compared to controls. This may have important implications for aseptic loosening of knee arthroplasty components and the decision to use scratch resistant components.