Vertebral Fractures: Which Radiological Criteria Are Better Associated With the Clinical Course of Osteoporosis?

STUDY PURPOSE: Morphometric methods categorize potential osteoporotic vertebral fractures (OVF) on the basis of loss of vertebral height. A particular example is the widely used semiquantitative morphometric tool proposed by Genant (GSQ). A newer morphologic algorithm-based qualitative (mABQ) tool focuses on vertebral end-plate damage in recognizing OVF. We used data from both sexes in the Canadian Multicentre Osteoporosis Study (CaMos) to compare the 2 methods in identifying OVF at baseline and during 10 years of follow-up. MATERIALS AND METHODS: We obtained lateral thoracic and lumbar spinal radiographs (T4-L4) 3 times, at 5-year intervals, in 828 participants of the population-based CaMos. Logistic regressions were used to study the association of 10-year changes in bone mineral density (BMD) with incident fractures. RESULTS: At baseline, 161 participants had grade 1 and 32 had grade 2 GSQ OVF; over the next 10 years, only 9 of these participants had sustained incident GSQ OVF. Contrastingly, 21 participants at baseline had grade 1 and 48 grade 2 mABQ events; over the next 10 years, 79 subjects experienced incident grade 1 or grade 2 mABQ events. Thus, incident grades 1 and 2 morphologic fractures were 8 times more common than morphometric deformities alone. Each 10-year decrease of 0.01 g/cm2 in total hip BMD was associated with a 4.1% (95% CI: 0.7-7.3) higher odds of having an incident vertebral fracture. CONCLUSIONS: This analysis further suggests that morphometric deformities and morphologic fractures constitute distinct entities; morphologic fractures conform more closely to the expected epidemiology of OVF.

Seventy Years and Counting: The Canadian Association of Radiologists' Journal.

Canadian radiology has its roots embedded in Montréal and this is no less true of the Canadian Association of Radiologists Journal, now celebrating its 70th Anniversary with the appointment of a new editor. A journal, Les Rayons-X-a monthly illustrated review published in Montréal and edited by Dr Henri Lasnier- preceded it by 40 years. Les Rayons-X was to last only 7 issues. However, Dr Lasnier clearly recognized the importance of a journal to what was then an emerging specialty. By 1950, the Canadian Association of Radiologists became the first specialty society in Canada to publish a scientific journal. We reflect on some facets of the evolution of the journal from a cottage industry to its adoption by a major publishing house and through the hands of 14 editors. In that time, radiology itself has undergone remarkable changes in its technological infrastructure leading to profound changes in the capacity of radiological practitioners and scientists to diagnose and treat disease. These changes themselves impose some constraints on a general radiology journal. The Association has at times faced substantial challenges that led to questions about its ability to sustain a journal in the face of competing priorities. Those challenges will likely recur in the future, not least in the face of other better-resourced journals. As the Canadian Association of Radiologists has evolved into a distinctive voice in Canadian medicine, we argue that a strong case can be made for preserving a platform for Canadian radiology featuring Canadian observations and perspectives, both scientific and "political."

The ISCD and Vertebral Fractures.

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.

The Radiology of Osteoporotic Vertebral Fractures Redux.

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.

A Qualitative Examination of the Ward Region of Interest as Imaged on Dual-Energy X-ray Absorptiometry Examinations: The "Wandering Ward Sign".

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.

The Radiology of Vertebral Fractures in Childhood Osteoporosis Related to Glucocorticoid Administration.

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.

Audit of Atypical Femoral Fractures and a Description of Some of Their Features.

PURPOSE: Atypical femoral fractures (AFF) are recently described events related to osteoporosis and, potentially, a rare result of antiresorptive treatment. METHODS: We set out to audit the diagnosis of AFF in an acute hospital. Charts and radiographs were reviewed retrospectively from patients diagnosed with subtrochanteric femoral fractures according to hospital discharge coding at Vancouver General Hospital (VGH), Canada, from January 2005 to March 2013. RESULTS: A total of 3084 patients were discharged from the hospital with a diagnosis of hip fracture between 2005 and 2013. Of these, 204 were coded as having had subtrochanteric fractures; 178 of the patients thus coded had radiographic evidence of other fracture types-usually intertrochanteric fractures. Eleven patients did not have available radiographs. Of the remaining 193 patients whose radiographs were reviewed, 24 (12.4%) fulfilled the published criteria for AFF. OUR OBSERVATIONS WERE: 1) laterality: 13 of 24 AFF (54.2%) were right-sided; 2) there was only one incomplete AFF in this series: a completed fracture was an inclusion criterion, but 1 patient with an AFF had both that fracture and an incomplete fracture and further foci of periosteal or endosteal foci of new bone (PENB) involving the contralateral femur; 3) radiologists had only diagnosed AFF in only 1 of the 24 patients with characteristic radiographic signs of AFF; 4) all but 1 patient had a focus of periosteal and/or endosteal new bone (PENB) through which the fracture line invariably passed, and in the 1 exception the radiography was too poor to be sure of this but there was a symmetrical contralateral focus of PENB; 5) in 19 of 24 patients there was an adequate image of part of the contralateral femur and of these 12 (63%) had a contralateral focus of PENB situated ±2.5 cm from the index lesion site when measured from the upper aspect of the greater trochanter, and in another patient a prior fracture of the contralateral femur had been treated surgically and it was at a symmetrical contralateral location from the index fracture.; 6) in 3 of the 19 patients multiple foci of PENB were detected on the lateral aspect of the contralateral femur even though the examination was of limited extent; and 7) AFFs were associated with bisphosphonate medication in 75% of the patients studied. CONCLUSIONS: Hospital discharge coding misclassified a great majority of femoral fractures as subtrochanteric. As an essential criteria for diagnosing AFF is their subtrochanteric location, this misclassification impaired our ability to retrospectively search for AFF patients. Radiologists tended not to report AFF when typical radiographic characteristics were present. Bilateral and multifocal disease is of interest in pointing to the diagnosis and in suggesting that the mechanism of injury in respect of these unusual fractures is more complex than simple low-energy trauma.

Atypical Femoral Fractures: A Teaching Perspective.

This article provides an overview of atypical femoral fractures with a highlight on their radiographic findings. Potent antiresorptive agents such as bisphosphonates or denosumab have been associated with the development of such fractures. However, at this time, a causal association has not been conclusively established. Atypical femoral fractures are insufficiency fractures, which frequently present with bone pain. Early identification of characteristic radiographic features and withdrawal of antiresorptive therapy may prevent the development of completed atypical femoral fractures.

Choice of lumbar spine bone density reference database for fracture prediction in men and women: a population-based analysis.

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.

Observer agreement in pediatric semiquantitative vertebral fracture diagnosis.

BACKGROUND: The Genant semiquantitative (GSQ) method has been a standard procedure for diagnosis of vertebral fractures in adults but has only recently been shown to be of clinical utility in children. Observer agreement using the GSQ method in this age group has not been described. OBJECTIVE: To evaluate observer agreement on vertebral readability and vertebral fracture diagnosis using the GSQ method in pediatric vertebral morphometry. MATERIALS AND METHODS: Spine radiographs of 186 children with acute lymphoblastic leukemia were evaluated independently by three radiologists using the same GSQ methodology as in adults. A subset of 100 radiographs was evaluated on two occasions. RESULTS: An average of 4.7% of vertebrae were unreadable for the three radiologists. Intraobserver Cohen's kappa (κ) on readability ranged from 0.434 to 0.648 at the vertebral level and from 0.416 to 0.611 at the patient level, while interobserver κ for readability had a range of 0.330 to 0.504 at the vertebral level and 0.295 to 0.467 at the patient level. Intraobserver κ for the presence of vertebral fracture had a range of 0.529 to 0.726 at the vertebral level and was 0.528 to 0.767 at the patient level. Interobserver κ for fracture at the vertebral level ranged from 0.455 to 0.548 and from 0.433 to 0.486 at the patient level. CONCLUSION: Most κ values for both intra- and interobserver agreement in applying the GSQ method to pediatric spine radiographs were in the moderate to substantial range, comparable to the performance of the technique in adult studies. The GSQ method should be considered for use in pediatric research and clinical practice.

The Accuracy of Incident Vertebral Fracture Detection in Children Using Targeted Case-Finding Approaches.

Vertebral fractures are clinically important sequelae of a wide array of pediatric diseases. In this study, we examined the accuracy of case-finding strategies for detecting incident vertebral fractures (IVF) over 2 years in glucocorticoid-treated children (n = 343) with leukemia, rheumatic disorders, or nephrotic syndrome. Two clinical situations were addressed: the prevalent vertebral fracture (PVF) scenario (when baseline PVF status was known), which assessed the utility of PVF and low lumbar spine bone mineral density (LS BMD; Z-score <-1.4), and the non-PVF scenario (when PVF status was unknown), which evaluated low LS BMD and back pain. LS BMD was measured by dual-energy X-ray absorptiometry, vertebral fractures were quantified on spine radiographs using the modified Genant semiquantitative method, and back pain was assessed by patient report. Forty-four patients (12.8%) had IVF. In the PVF scenario, both low LS BMD and PVF were significant predictors of IVF. Using PVF to determine which patients should have radiographs, 11% would undergo radiography (95% confidence interval [CI] 8-15) with 46% of IVF (95% CI 30-61) detected. Sensitivity would be higher with a strategy of PVF or low LS BMD at baseline (73%; 95% CI 57-85) but would require radiographs in 37% of children (95% CI 32-42). In the non-PVF scenario, the strategy of low LS BMD and back pain produced the highest specificity of any non-PVF model at 87% (95% CI 83-91), the greatest overall accuracy at 82% (95% CI 78-86), and the lowest radiography rate at 17% (95% CI 14-22). Low LS BMD or back pain in the non-PVF scenario produced the highest sensitivity at 82% (95% CI 67-92), but required radiographs in 65% (95% CI 60-70). These results provide guidance for targeting spine radiography in children at risk for IVF. © 2021 American Society for Bone and Mineral Research (ASBMR).

Osteoporotic Fractures and Vertebral Body Reshaping in Children With Glucocorticoid-treated Rheumatic Disorders.

CONTEXT: Osteoporotic fractures are an important cause of morbidity in children with glucocorticoid-treated rheumatic disorders. OBJECTIVE: This work aims to evaluate the incidence and predictors of osteoporotic fractures and potential for recovery over six years following glucocorticoid (GC) initiation in children with rheumatic disorders. METHODS: Children with GC-treated rheumatic disorders were evaluated through a prospective inception cohort study led by the Canadian STeroid-induced Osteoporosis in the Pediatric Population (STOPP) Consortium. Clinical outcomes included lumbar spine bone mineral density (LS BMD), vertebral fractures (VF), non-VF, and vertebral body reshaping. RESULTS: A total of 136 children with GC-treated rheumatic disorders were enrolled (mean age 9.9 years, SD 4.4). The 6-year cumulative fracture incidence was 16.3% for VF, and 10.1% for non-VF. GC exposure was highest in the first 6 months, and 24 of 38 VF (63%) occurred in the first 2 years. Following VF, 16 of 19 children (84%) had complete vertebral body reshaping. Increases in disease activity and body mass index z scores in the first year and declines in LS BMD z scores in the first 6 months predicted incident VF over the 6 years, while higher average daily GC doses predicted both incident VF and non-VF. LS BMD z scores were lowest at 6 months (mean -0.9, SD 1.2) and remained low by 6 years even when adjusted for height z scores (-0.6, SD 0.9). CONCLUSION: VF occurred early and were more common than non-VF in children with GC-treated rheumatic disorders. Eighty-four percent of children with VF underwent complete vertebral body reshaping, whereas vertebral deformity persisted in the remainder of children. On average, LS BMD z scores remained low at 6 years, consistent with incomplete recovery.

Radiographic osteoporotic vertebral fractures in elderly men: a brief review focusing on differences between the sexes.

Bone loss occurs in both sexes as a result of ageing but is exacerbated in women by the hormonal changes associated with menopause. Unlike in women, secondary osteoporosis occurs in almost half of men diagnosed with osteoporosis. Moreover, vertebral fractures (VFs) seen in elderly men may more likely be the result of high energy trauma. The osteoporotic vertebral fracture (OVF) radiograph diagnosis criteria for women may not be directly applicable for men. Particular attention should be paid to the mid-thoracic level where over-diagnosis commonly occurs. For wedge-shaped vertebral deformities (VDs) or VDs with anterior height reduction only, a diagnosis of OVF requires great caution, as they are poorly correlated to bone mineral density (BMD). For age-matched subjects, it is likely that elderly men's prevalent radiographic OVFs are approximately half of the elderly women's. This male-female ratio is very similar to other clinical fractures such as those occurring at the hip. Even so, the clinical relevance of OVF in elderly men may be less than that of elderly women. On the other hand, for elderly men with hip BMD-based osteoporosis, the OVF risk is as high as that of osteoporotic women. Elderly Chinese men have a lower OVF prevalence than age-matched Caucasian men.

The Accuracy of Prevalent Vertebral Fracture Detection in Children Using Targeted Case-Finding Approaches.

Due to concerns about cumulative radiation exposure in the pediatric population, it is not standard practice to perform spine radiographs in most conditions that predispose to vertebral fracture (VF). In this study we examined the accuracy of two clinical predictors, back pain and lumbar spine bone mineral density (LS BMD), to derive four case-finding paradigms for detection of prevalent VF (PVF). Subjects were 400 children at risk for PVF (leukemia 186, rheumatic disorders 135, nephrotic syndrome 79). Back pain was assessed by patient report, LS BMD was measured by dual-energy X-ray absorptiometry, and PVF were quantified on spine radiographs using the modified Genant semiquantitative method. Forty-four patients (11.0%) had PVF. Logistic regression analysis between LS BMD and PVF produced an odds ratio (OR) of 1.9 (95% confidence interval [CI], 1.5 to 2.5) per reduction in Z-score unit, an area under the receiver operating characteristic curve of 0.70 (95% CI, 0.60 to 0.79), and an optimal BMD Z-score cutoff of -1.6. Case identification using either low BMD alone (Z-score < -1.6) or back pain alone gave similar results for sensitivity (55%, 52%, respectively), specificity (78%, 81%, respectively), positive predictive value (PPV; 24%, 25%, respectively), and negative predictive value (NPV; 93%, 93%, respectively). The paradigm using low BMD plus back pain produced lower sensitivity (32%), higher specificity (96%), higher PPV (47%), and similar NPV (92%). The approach using low BMD or back pain had the highest sensitivity (75%), lowest specificity (64%), lowest PPV (20%), and highest NPV (95%). All paradigms had increased sensitivities for higher fracture grades. Our results show that BMD and back pain history can be used to identify children with the highest risk of PVF so that radiography can be used judiciously. The specific paradigm to be applied will depend on the expected PVF rate and the clinical approach to the use of radiography. © 2019 American Society for Bone and Mineral Research.