Three-dimensional surface analysis of young adult human articular cartilage

The objective of this investigation was to determine whether the surface of young adult human articular cartilage was smooth as defined by industrial standards for metal surfaces. Human articular cartilage with attached subchondral bone from the midregion of the trochlear surface of the talus was obtained postmortem from 7 donors (aged 29 +/- 9 y). The specimens were processed using multiple fixation techniques prior to scanning electron microscopy and 3-dimensional stereoscopic analysis. Three-dimensional stereoscopic data showed that 92.78 +/- 16.90% of the articular surface was devoid of surface irregularities and was considered to be smooth. The remaining regions comprising 7.22 +/- 17.20% of the area demonstrated bumps measuring 7.70 +/- 4.58 microns in height. When the results of this study were compared with the international standards for surface preparations used by machinists for metal surfaces, they clearly showed that even when the regions with bumps were considered, the articular cartilage surface could be characterised as smooth.