DEFINITION

Osteoporosis is a bone disease characterized by low bone density and disruption of the microarchitecture of bone tissue, resulting in an increase in bone fragility and the risk of pathological fractures. A pathologic fracture is defined as one resulting from minimal force, equivalent to or less than a fall from a standing position. 

Clinically, the diagnosis of osteoporosis is established either by the presence of at least one pathologic fracture or, in individuals without a history of fracture, based on the measurement of bone mineral density.

In contrast to osteomalacia, the bone that is present is normally calcified, but shows a disturbance in its microarchitecture (fig. 1) which consists of a reduction and thinning of the number of trabeculae, especially the horizontal ones, and a breakdown of their continuity, resulting in a reduction of their supporting ability. However, the above does not necessarily lead to a fracture if there are no other (exoskeletal) effects such as: falls, changes in the soft tissues (muscle, fat) that protect the bone, the geometry of the bone.

TYPES

Osteoporosis is divided (Table 1) into idiopathic, which concerns the majority of osteoporotic patients, and secondary. Idiopathic mainly includes postmenopausal osteoporosis in women and osteoporosis occurring in old age in both men and women. It also includes rare cases of osteoporosis in young people where no specific cause is recognized and is mainly attributed to failure to reach maximum bone density. Secondary refers to the loss of bone density due to specific clinical entities, without always knowing the mechanism that leads to the bone disease.

GRADUATE COURSES IN ENDOCRINOLOGY AND DIABETES- DEPARTMENT OF ENDOCRINOLOGY DIABETES AND METABOLISM OF EVANGELISMOS GENERAL HOSPITAL OF ATHENS- 2004