Quantitative measurement of human articular surface topography in vitro by profile recorder and stereo‐microscopy techniques

SUMMARY The degree of irregularity presented by the 20–40 μm diameter depressions in adult human articular surfaces was measured in vitro , using the scanning electron microscope (SEM), replication, stereo‐microscopy and profile recording techniques. Using stereo‐microscopy, the measured articular surface depressions varied from 0.9 to 15 μm in depth and the corresponding humps on the replicas varied from 0.3 to 8.9 μm in height. The heights of the replicated contours measured by the profile recording device varied from 0.2 to 5 μm. It was emphasized that, while these values give some indication as to the possible degree of surface irregularity in vivo , the actual contours in a living, load‐bearing joint may be quite different.