Femoral prosthetic heads and their significance in polyethylene wear

We used scanning electron microscopy to perform an ultrastructural analysis and two optical interferometric profilers to measure roughness on 40 prosthetic femoral heads. We expressed roughness as Ra (roughness average) value and Rsk (roughness skewness) value. Our results show that in order to obtain an ideal surface finish a low or not very high Ra value and a negative Rsk value are needed. The presence of depressions or holes (rather than scratches) with smooth (rather than sharp) edges seems to improve the lubrication and wettability properties.