LAUSR

Problem • Cracks in bone and articular calcified cartilage (ACC) of the subchondral plate heal with a High Density Mineralised Infill (HDMI) which disappears with demineralisation, and thus becomes lost to knowledge, science, memory and even OARSI. • HDMI also extrudes into hyaline articular cartilage (HAC) as High Density Mineralised Protrusions (HDMPs), which fragment and act as a cutting and grinding agent, damaging HAC from within. • We wish to know more about the structure and composition of HDMPs. • We recently prepared thin sections from the front face of bone blocks embedded in PMMA previously studied by backscattered electron scanning electron microscopy (BSESEM) and X-ray microtomography (XMT) by laser-ablation microtomy (LAM) and wanted to know if this method could be applied to this rather intractable problem.