Osteoporosis literally means ‘porous bones’. It is a condition that weakens the bones and makes them more susceptible to fractures (breaks).
Our bones gradually build up and strengthen until our mid-20s, this is when our bones are at their strongest and most dense. After this the bones gradually lose their density, and in women this process occurs more rapidly after the menopause. Often we find that some bones are more affected than others, which varies among individuals.
Osteoporosis mainly affects post-menopausal women, although older men can also suffer from the condition. It is characterised by reduced bone mass and bone strength and can increase the risk of fragility fractures. A fragility fracture usually results from mechanical forces that would not ordinarily result in a fracture, known as low-level (or 'low energy') trauma, for example by falling from standing height. The milder form of reduced bone mass is called osteopenia, when bone mineral density is lower than normal but not low enough to establish a diagnosis of osteoporosis.