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While analyzing dual-energy X-ray absorptiometry (DXA) examinations, we observed that, on occasion, the Ward region of interest (ROI) was positioned either unexpectedly or differently between successive examinations. When this occurred, it appeared to be either a marker of a compromised examination or of incident disease. This prompted a systematic inquiry. It became apparent that, while in general seeking the region of least areal density, the Ward ROI is positioned differently by the machines available to us from 2 particular manufacturers (General Electric Co. and Hologic Inc.). Three reviews were thus undertaken: (1) a prospective systematic examination of 200 unselected consecutive DXA examinations made with a General Electric Co. machine, 80 having had follow-up examinations and 245 made with a Hologic Inc. device; (2) a prospective systematic examination of 625 consecutive, unselected DXA examinations that were repeat examinations; and (3) a retrospective examination of a file of 86 cases collected for pedagogical purposes, predominantly made with a Hologic Inc. device. The commonest cause of an unusual position of the Ward area was compromised patient positioning or change in body habitus. Changes between examinations were, in addition if less often, apt to reflect physiological change or disease. Unusual positioning or a change in position of the Ward ROI is easily observed. It does not occur frequently, but, when it does, it may be useful in directing attention to either technical factors or incidental diseases. Observation of the position of the Ward ROI may thus be a quality assurance, and occasionally a diagnostic, tool., (Copyright © 2016 International Society for Clinical Densitometry. Published by Elsevier Inc. All rights reserved.)

When a low-energy fracture occurs, then osteoporosis has progressed to the point of bony structural failure. Because vertebral fractures are the commonest type of osteoporotic fracture, the correct identification of them becomes important for diagnosis, risk estimation, and management. However, there are no uniformly agreed criteria for their diagnosis. The purpose of this review was to examine the diagnostic radiological strategies available and suggest a coherent approach to diagnosis. Diagnosis had come to focus on comparative changes in vertebral dimensions. However, it has become apparent that mild reductions in vertebral height are of uncertain implication. The importance of structural damage in diagnosis has become recognized in parallel. Relative reductions in vertebral height may not be a necessary nor sufficient criterion by which to diagnose a fracture., (Copyright © 2016 The International Society for Clinical Densitometry. Published by Elsevier Inc. All rights reserved.)

Some 30 years ago the diagnosis of osteoporosis relied primarily on the measurement of bone mineral density by DXA. More recently, however, it was recognized that vertebral fractures are an important predictor of future fractures and that they reflect some aspect of bone fragility not captured by BMD measurement. In response to that, DXA manufacturers developed VFA, spine imaging on the densitometer, which allowed integration of BMD with information on vertebral fractures obtained at the same visit. ISCD has been instrumental in several aspects of VFA use such as developing and teaching courses for VFA or more broadly, for recognition of vertebral fractures; in developing guidelines for performance, interpretation and reporting of the VFA; and in advocating for reimbursement for VFA tests performed in the clinical practice. ISCD is poised to continue as a leader in vertebral fracture recognition and application of VFA to clinical practice and research., (Copyright © 2016 The International Society for Clinical Densitometry. Published by Elsevier Inc. All rights reserved.)

A number of unusual conditions cause decreased bone mass and density in children and these may be associated with low-trauma fractures. However, a series of reports have more recently identified that children with chronic disease sustain vertebral fractures (VFs) much more often than had been suspected. The common denominator involved is glucocorticoid (GC) administration, although other factors such as disease activity come into play. This review will focus on the imaging findings in this form of secondary osteoporosis. Spinal fractures in children have been found to correlate with back pain. At the same time, up to 2/3 of children with VFs in the GC-treated setting are asymptomatic, underscoring the importance of routine surveillance in at-risk children. Other predictors of prevalent and incident VFs include GC exposure (average daily and cumulative dose), declines in lumbar spine bone mineral density Z-scores and increases in body mass index Z-scores, as well as increases in disease activity scores. The imaging diagnosis of osteoporotic VFs in children is made differently from that in adults because immature vertebral bodies continue to ossify during growth. Thus, it is not possible to assess the vertebral end plates or periphery until late, as enchondral ossification extends centripetally within the centrum. Diagnosis, therefore, is much more dependent upon changes in shape than on loss of structural integrity, which may have a more prominent diagnostic role in adults. However, children have a unique ability to model (a growth-dependent process) and thereby reshape previously fractured vertebral bodies. If the underlying disease is successfully treated and the child has sufficient residual growth potential, this means that, on one hand, treatment of the bone disease may be of more limited duration, and, as a last recourse, the diagnosis may be apparent retrospectively., (Copyright © 2015 International Society for Clinical Densitometry. Published by Elsevier Inc. All rights reserved.)

The diagnosis of osteoporosis in men is controversial, although most studies demonstrate similar fracture rates for men and women with the same level of hip bone mineral density (BMD). Whether this applies to the lumbar spine is currently uncertain and has important implications with respect to choice of reference population for T-score calculation and osteoporosis diagnosis. This question was specifically addressed in the population-based Canadian Multicentre Osteoporosis Study cohort of 4745 women and 1887 men ages 50+ yr at the time of baseline lumbar spine dual energy x-ray absorptiometry. In up to 10 yr of observation, incident clinical major osteoporotic fractures occurred in 110 men (5.8%) vs 543 women (11.4%) (p < 0.001). Mean lumbar spine BMD in men was greater than in women, both among those with and those without incident major osteoporotic fracture (p < 0.001). Men were at slightly lower risk for incident major osteoporotic fracture than women for an equivalent lumbar spine BMD (age- and BMD-adjusted rate ratio 0.75, 95% confidence interval 0.60-0.93, p = 0.008) with similar findings after adjustment for the World Health Organization fracture risk assessment clinical risk factors or competing mortality. No significant sex difference in the BMD relationship was seen for vertebral fractures (clinical or radiographic) or for all fractures. In summary, this large population-based longitudinal cohort study found similar or lower fracture risk for men vs women after adjustment for absolute lumbar spine BMD and additional covariates. The least complicated model for describing fracture risk is therefore to use the same reference lumbar spine data for generating T-scores in men and women., (Copyright © 2014 The International Society for Clinical Densitometry. Published by Elsevier Inc. All rights reserved.)

The study of race/ethnicity in relation to health outcomes and health disparities is of great importance in medicine. This is as true in the field of osteoporosis as it is in others, and it comes into sharp focus when the question of population-specific reference data for bone densitometry arises. Race/ethnicity can be viewed as both an ecosocial construct and as a biomedical concept. Whether or not, and how, to use race/ethnicity in fracture assessment potentially places these two paradigms in opposition. In this article, some of the issues that need to be considered to develop a rational approach to reference data selection and a globally acceptable measure of fracture risk are reviewed. Race/ethnicity is often a proxy for other disease-related risk factors. Understanding fundamental risk factors goes beyond the language of race/ethnicity.

The International Society for Clinical Densitometry (ISCD) is a multidisciplinary nonprofit global organization formed to ensure excellence in densitometry imaging, interpretation, and application. The Canadian panel of the ISCD represents ISCD in Canada and oversees Canadian bone densitometry certification programs. The standards of care from the Canadian panel of the ISCD have been developed in order to establish the minimum level of acceptable performance for the practice of bone densitometry in Canada. A variety of techniques are available for skeletal assessment of bone mineral density, which vary in accuracy, precision, and clinical utility as well as availability. This article focuses on central dual X-ray absorptiometry in adults and does not address densitometry in the pediatric population. Other technologies will be addressed in a subsequent article.

The International Society for Clinical Densitometry (ISCD) is a multidisciplinary nonprofit global organization formed to ensure excellence in densitometry imaging, interpretation, and application. The Canadian panel of the ISCD represents ISCD in Canada and oversees Canadian bone densitometry certification programs. The standards of care from the Canadian panel of the ISCD have been developed in order to establish the minimum level of acceptable performance for the practice of bone densitometry in Canada. A variety of techniques are available for skeletal assessment of bone mineral density, which vary in accuracy, precision, and clinical utility as well as availability. This article focuses on central dual X-ray absorptiometry in adults and does not address densitometry in the pediatric population. Other technologies will be addressed in a subsequent article.

Following a 52-wk randomized controlled trial of intermittent cyclic etidronate therapy in patients using corticosteroids, we performed a 52-wk open-label trial of calcium alone in 114 corticosteroid-treated patients to determine whether the beneficial effect of etidronate is maintained after the drug is discontinued. All patients were given 500 mg/d of elemental calcium. Sixty-one and 53 patients made up the former placebo and etidronate groups, respectively. A total of 89 (98%) of patients in the former placebo and etidronate groups remained on corticosteroids throughout the second year. The mean (SE) percentage change in bone mineral density of the lumbar spine, femoral neck, and trochanter were compared between groups. The difference between groups in mean percentage change from baseline (wk 0, initiation of etidronate or placebo therapy) in the bone density of the lumbar spine, femoral neck, and trochanter, following 104 wk, was 3.8 (0.9), 3.0 (1.1), and 4.3 (1.1), respectively (p < 0.05, all sites), in favor of the former etidronate group. While not significant, the former placebo group demonstrated a slightly larger rate of decline in bone density over the second year than the former etidronate group at all three sites. Following the discontinuation of etidronate therapy, there was no accelerated bone loss and there was evidence of a residual protective effect in both the lumbar spine and femoral neck for up to 1 yr posttreatment.