Evolutionary Pathways of Diagnosis in Osteoporosis

Abstract

Osteoporosis was formally identified as a disease by a group of World Health Organization (WHO) experts in 1994 resulting in publication of "Assessment of Fracture Risk and its Application to Screening for Postmenopausal Osteoporosis" (WHO Technical Report Series, 1994). Osteoporosis is defined as a skeletal disorder characterized by compromised bone strength predisposing to an increased risk of fracture. Bone strength reflects the integration of two main features: bone density and bone quality. Bone density is expressed as grams of mineral per area or volume and in any given individual is determined by peak bone mass and amount of bone loss. Bone quality refers to architecture, turnover, damage accumulation and mineralization (NIH Consensus, 2001). Osteoporosis occurs in all populations and at all ages and is a devastating disorder with significant physical, psychosocial and financial consequences. The WHO operationally defines osteoporosis as a bone density at least 2.5 standard deviations below the mean peak bone mass for healthy young adult white women, also referred to as a T-score of –2.5. Because of the difficulty in accurate measurement and standardization between instruments and sites, controversy exists among experts regarding the continued use of this diagnostic criterion. So different instruments have not the same performance in regard to a accurate bone density measurement. The aims of this chapter are stated in table 1.