This is a condition in which a loss of bone tissue occurs, resulting in brittle bones which are prone to fracture. Loss of bone density is a feature of ageing and affects older people of both sexes. There may be few symptoms but those that occur include backache, loss of height and deformation of the spine. Bones fracture easily with minor falls.

The cause in women appears to be related to the decline in oestrogen levels after menopause or removal of ovaries due to disease. Prolonged treatment with cortico-steroid drugs is also a possible cause and a low calcium intake results in this condition.