3 Biology and metabolism of mineralised tissues

The metabolic bone diseases are characterised by disruptions to normal formation, mineralisation, and removal of mineralised tissues. These processes are affected differently in the various diseases and therefore produce a range of alterations in tissues, related in part to biological age and sex, diet and mechanical loading. The normal actions of bone cells are set out along with an introduction to the role of hormones in adjusting the formation and activity of bone cells and the effects of products secreted by cells (RANKL/RANK/OPG) in regulating bone metabolism. This chapter provides readers with a grounding in normal bone biology and metabolism placing them in a position to understand the alterations that occur in response to disease. Guidance on the basic biological mechanisms that underlie lesion formation is provided. A series of bullet points are used to summarise the core concepts covered.