General Information

Description

PubMed25182228Osteoporosis international : a journal established as result of cooperation between the European Foundation for Osteoporosis and the National Osteoporosis Foundation of the USAOsteoporos Int2014100125102359-812359osteoporosis is a generalized systemic skeletal disorder characterized by low bone mineral density, deterioration of bone quality, and compromised bone strength, often leading to fragility fracture due to excessive bone loading from a fall or certain activities of daily living¹
- in adults ≥ 50 years old, osteoporosis is diagnosed in patients with any of the following¹
  - vertebral or hip fracture in absence of major trauma (independent of bone mineral density results)
  - T-score ≤ -2.5 when determined at lumbar spine or hip; 33% (one-third) radius may be used for diagnosis of osteoporosis when lumbar spine and hip cannot be measured or interpreted
- PubMed22684497Osteoporosis international : a journal established as result of cooperation between the European Foundation for Osteoporosis and the National Osteoporosis Foundation of the USAOsteoporos Int2012120123122735-482735in younger adults, low bone mineral density defined by z-score < -2 or T-score ≤ -2.5 (depending on the professional organization) is not classified as osteoporosis unless an associated chronic condition known to affect bone metabolism or a fragility fracture is present (Osteoporos Int 2012 Dec;23(12):2735)
risk factors for osteoporosis may include nonmodifiable factors (such as older age and female sex), lifestyle factors (such as excessive alcohol intake and low calcium intake), and medical conditions and medications associated with secondary osteoporosis^1,2,3

Definitions

fragility (low trauma) fracture - fracture from minor trauma (for instance, fall from standing height or less) or that occurs spontaneously (Eur J Rheumatol 2017 Mar;4(1):46 full-text)

PubMed28492856Annals of internal medicineAnn Intern Med2017060616611818-839818T-score - bone mineral density score representing number of standard deviations above or below mean for normal young population (Ann Intern Med 2017 Jun 6;166(11):818 full-text)

Table 1. World Health Organization Classification of Bone Health According to T-score for Postmenopausal Women and Men ≥ 50 Years Old
Classification	BMD	T-score
Normal	Within 1 SD of mean level for young adult reference population	T-score ≥ -1.0
Osteopenia	Between 1 and 2.5 SD below mean level for young adult reference population	T-score between -1 and -2.5
Osteoporosis	≥ 2.5 SD below mean level for young adult reference population	T-score ≤ -2.5
Severe or established osteoporosis	≥ 2.5 SD below mean level for young adult reference population plus fragility fractures	T-score ≤ -2.5 plus ≥ 1 fracture
Abbreviations: BMD, bone mineral density; SD, standard deviation. Reference - Osteoporos Int 2014 Oct;25(10):2359 full-text, correction can be found in Osteoporos Int 2015 Jul;26(7):2045, commentary can be found in JAMA 2015 Apr 14;313(14):1467.

z-score - bone mineral density score representing number of standard deviations above or below mean value for age-, race-, ethnicity-, and sex-matched persons¹