The Radiology of Osteoporotic Vertebral Fractures Redux

Diagnostic imaging in patients with vertebral compression fractures

Vertebral compression fractures by osteoporosis (OVF) is usually a diagnostic problem and coincides on the age group of metastatic vertebral compression fractures (MVF). Although radiography is the first diagnostic technique, generally is not accurate for depicting demineralization and soft tissue lesions. Magnetic resonance (MRI) is the diagnostic choice. The most relevant signs are Intravertebral fluid collection or fluid signal, other vertebral deformities without edema and older age. Among the most relevant findings for diagnosis MVF are soft tissue mass and pedicle intensity signal asymmetries. However, reproducibility of these findings in clinical practice is moderate.

Radiological diagnosis of prevalent osteoporotic vertebral fracture on radiographs: an interim consensus from a group of experts of the ESSR osteoporosis and metabolism subcommittee

When a low-energy trauma induces an acute vertebral fracture (VF) with clinical symptoms, a definitive diagnosis of osteoporotic vertebral fracture (OVF) can be made. Beyond that, a "gold" radiographic standard to distinguish osteoporotic from non-osteoporotic VFs does not exist. Fracture-shaped vertebral deformity (FSVD) is defined as a deformity radiographically indistinguishable from vertebral fracture according to the best of the reading radiologist's knowledge. FSVD is not uncommon among young populations with normal bone strength. FSVD among an older population is called osteoporotic-like vertebral fracture (OLVF) when the FSVD is likely to be associated with compromised bone strength. In more severe grade deformities or when a vertebra is collapsed, OVF diagnosis can be made with a relatively high degree of certainty by experienced readers. In "milder" cases, OVF is often diagnosed based on a high probability rather than an absolute diagnosis. After excluding known mimickers, singular vertebral wedging in older women is statistically most likely an OLVF. For older women, three non-adjacent minimal grade OLVF (< 20% height loss), one minimal grade OLVF and one mild OLVF (20-25% height loss), or one OLVF with ≥ 25% height loss, meet the diagnosis of osteoporosis. For older men, a single OLVF with < 40% height loss may be insufficient to suggest the subject is osteoporotic. Common OLVF differential diagnoses include X-ray projection artifacts and scoliosis, acquired and developmental short vertebrae, osteoarthritic wedging, oncological deformities, deformity due to high-energy trauma VF, lateral hyperosteogeny of a vertebral body, Cupid's bow, and expansive endplate, among others.

High Rate of Pulmonary Cement Embolism after Cement-Augmented Pedicle Screw Fixation: A 12-Year Single-Center Study

BACKGROUND

 The global trend toward increased life expectancy because of remarkable improvements in health care quality has drawn increased attention to osteoporotic fractures and degenerative spine diseases. Cement-augmented pedicle screw fixation has been established as the mainstay treatment for patients with poor bone quality. This study aimed to determine the number of patients with cement leakage and pulmonary cement embolism (PCE) as detected on thoracic computed tomography (CT), and to assess the potential risk factors for PCE.

METHODS

 Patients undergoing cement-augmented pedicle screw placement in our institution between May 2008 and December 2020 were included. Data regarding baseline characteristics, complications, and cement leakage rates were collected. Indications for the performance of a postoperative thoracic CT due to the suspicion of PCE were intra- or postoperative complications, or postoperative oxygen supplementation. Moreover, PCE was accidently diagnosed because the thoracic CT was performed for medical reasons other than the suspicion of PCE (tumor staging, severe pneumonia, or exacerbated chronic pulmonary obstructive disease).

RESULTS

 A total of 104 patients with a mean age of 72.8 years (standard deviation of 6.7) were included. Of 802 screws, 573 were cement augmented. Of the 104 patients, 44 (42.3%) underwent thoracic CT scans to diagnose PCE; additionally, 67 (64.4%) demonstrated cement leakage, of whom 27 developed PCE and 4 were symptomatic. Cement-augmented thoracic screws were a risk factor for PCE (odds ratio: 1.5; 95% confidence interval: 1.2-2.1; p = 0.004).

CONCLUSIONS

 This study showed a high prevalence of cement leakage after cement-augmented pedicle screw insertion, with a relatively frequent incidence of PCE, as tracked by thoracic CT scans. Cement-augmented thoracic screw placement was a unique risk factor for PCE.

Factors influencing vertebral collapse in osteoporotic vertebral fractures: a case-control study of symptomatic patients attended in the emergency department

This study aimed to identify risk factors for the collapse of osteoporotic vertebral fractures (OVFs). We analyzed data from conventional radiography and computed tomography in patients with OVFs and found that older age and two radiological measurements were predictive for vertebral collapse. These factors can be useful for clinical practice.

PURPOSE

To identify risk factors for collapse of osteoporotic vertebral fractures (OVF) on computed tomography (CT) and conventional radiography (CR).

METHODS

This is a retrospective case-control study including a series of patients with OVF diagnosed at the emergency department of our institution from January to September 2019. Inclusion criteria were to have standing CR and supine CT within 2 weeks after the diagnosis of OVF and a follow-up CR at 6 months or later. We evaluated different imaging measurements at the initial diagnostic examinations, including vertebral height loss, local kyphosis, vertebral density, and fracture type according to the grading systems of Genant, Sugita, Association of Osteosynthesis (AO) Spine, and the German Society for Orthopaedics and Trauma. Vertebral collapse was defined as loss of ≥ 50% of vertebral area or height. Cases and controls were defined as OVFs which collapse and do not collapse, respectively, on follow-up.

RESULTS

Fifty-six patients were included in the study, with a mean age of 72.6 ± 1.2 years, including 48 women. Twenty-five (44.6%) OVFs developed collapse on follow-up. None of the fracture classification systems were found to be predictive of collapse. Multivariate analysis showed that older age, increased density ratio (≥ 2) between the fractured and non-fractured vertebral bodies, and a ≥ 6% difference in posterior vertebral height (PVH) loss between standing CR and supine CT exhibited 88% discriminative power in predicting vertebral collapse.

CONCLUSIONS

Age over 72.5 years, a density ratio ≥ 2 between the fractured and non-fractured vertebral bodies, and a difference equal to or higher than 6% in PVH loss between standing CR and supine CT, are risk factors for developing vertebral collapse after OVF.

The value of radiomics-based CT combined with machine learning in the diagnosis of occult vertebral fractures

PURPOSE

To develop and evaluate the performance of radiomics-based computed tomography (CT) combined with machine learning algorithms in detecting occult vertebral fractures (OVFs).

MATERIALS AND METHODS

128 vertebrae including 64 with OVF confirmed by magnetic resonance imaging and 64 corresponding control vertebrae from 57 patients who underwent chest/abdominal CT scans, were included. The CT radiomics features on mid-axial and mid-sagittal plane of each vertebra were extracted. The fractured and normal vertebrae were randomly divided into training set and validation set at a ratio of 8:2. Pearson correlation analyses and least absolute shrinkage and selection operator were used for selecting sagittal and axial features, respectively. Three machine-learning algorithms were used to construct the radiomics models based on the residual features. Receiver operating characteristic (ROC) analysis was used to verify the performance of model.

RESULTS

For mid-axial CT imaging, 6 radiomics parameters were obtained and used for building the models. The logistic regression (LR) algorithm showed the best performance with area under the ROC curves (AUC) of training and validation sets of 0.682 and 0.775. For mid-sagittal CT imaging, 5 parameters were selected, and LR algorithms showed the best performance with AUC of training and validation sets of 0.832 and 0.882. The LR model based on sagittal CT yielded the best performance, with an accuracy of 0.846, sensitivity of 0.846, and specificity of 0.846.

CONCLUSION

Machine learning based on CT radiomics features allows for the detection of OVFs, especially the LR model based on the radiomics of sagittal imaging, which indicates it is promising to further combine with deep learning to achieve automatic recognition of OVFs to reduce the associated secondary injury.

Value of 18F-FDG-PET/CT radiomics combined with clinical variables in the differential diagnosis of malignant and benign vertebral compression fractures

BACKGROUND

Vertebral compression fractures (VCFs) are common clinical problems that arise from various reasons. The differential diagnosis of benign and malignant VCFs is challenging. This study was designed to develop and validate a radiomics model to predict benign and malignant VCFs with 18F-fluorodeoxyglucose-positron emission tomography/computed tomography (18F-FDG-PET/CT).

RESULTS

Twenty-six features (9 PET features and 17 CT features) and eight clinical variables (age, SUVmax, SUVpeak, SULmax, SULpeak, osteolytic destruction, fracture line, and appendices/posterior vertebrae involvement) were ultimately selected. The area under the curve (AUCs) of the radiomics and clinical-radiomics models were significantly different from that of the clinical model in both the training group (0.986, 0.987 vs. 0.884, p < 0.05) and test group (0.962, 0.948 vs. 0.858, p < 0.05), while there was no significant difference between the radiomics model and clinical-radiomics model (p > 0.05). The accuracies of the radiomics and clinical-radiomics models were 94.0% and 95.0% in the training group and 93.2% and 93.2% in the test group, respectively. The three models all showed good calibration (Hosmer-Lemeshow test, p > 0.05). According to the decision curve analysis (DCA), the radiomics model and clinical-radiomics model exhibited higher overall net benefit than the clinical model.

CONCLUSIONS

The PET/CT-based radiomics and clinical-radiomics models showed good performance in distinguishing between malignant and benign VCFs. The radiomics method may be valuable for treatment decision-making.

The Correlation of Global Spinal Realignment With the Quality of Life After Corrective Surgery for Delayed Thoracolumbar Osteoporotic Fracture-Related Kyphosis

BACKGROUND AND OBJECTIVES

Few studies have been conducted to evaluate the precise impact of corrective surgery on sagittal spinal realignment and clinical outcomes in cases of delayed thoracolumbar osteoporotic fracture-related kyphosis. To assess the efficacy of corrective surgery on sagittal spinal alignment and investigate the relationship between spinal alignment and health-related quality of life (HRQoL) in patients with delayed thoracolumbar osteoporotic fracture-related kyphosis.

METHODS

A total of 78 patients were enrolled. The characteristics and surgical variables were meticulously documented. The sagittal spinal parameters were measured, and the HRQoL was evaluated using Oswestry Disability Index (ODI), SF-12 Physical Component Score (SF-12 PCS), and Scoliosis Research Society-22 Patient Questionnaire (SRS-22) before and after surgery. The changes in spinal parameters and HRQoL were analyzed through the paired t -test. The Pearson correlation analysis was performed to analyze the correlation of parameters with HRQoL. Then, a multiple stepwise regression analysis was performed with HRQoL scores as the dependent variable and spinal parameters as the independent variable.

RESULTS

The operative time was 185.9 ± 33.2 min, and the estimated blood loss was 782.8 ± 145.2 mL. The results of the paired t -test revealed a significant difference preoperatively and at the final follow-up in the thoracic kyphosis, thoracolumbar kyphosis (TLK), lumbar lordosis, T9 tilt, pelvic tilt, sacral slope, sagittal vertical axis, and spinosacral angle as well as the ODI, SF-12 PCS, and SRS-22 ( P < .05). Multiple stepwise regression analysis revealed that TLK and pelvic tilt, TLK and sagittal vertical axis, and TLK were the primary parameters affecting the ODI, SF-12 PCS, and SRS-22, respectively.

CONCLUSION

Corrective surgery can effectively realign the global spine and improve HRQoL in patients with delayed thoracolumbar osteoporotic fracture-related kyphosis. The change of TLK is a driving factor to realign the global spine.

Differential risk of fracture attributable to type 2 diabetes mellitus according to skeletal site

BACKGROUND

Impaired bone quality, especially related to accumulation of advanced glycation end-products (AGEs) and higher incidence of falls contribute substantially to a higher risk of fracture associated with type 2 diabetes mellitus (T2DM). These factors may predispose to fractures more at skeletal sites where impaired bone toughness and falls play a larger pathogenic role (such as hip fractures) compared to skeletal sites where they are less important (such as vertebral fractures).

OBJECTIVE

To determine if the associations of T2DM with prevalent and incident vertebral fractures are as strong as they are for hip and other non-vertebral fractures.

METHODS

Amongst 80,238 individuals in the Manitoba Bone Density Program database (mean [SD] age 64.4 [11.1] years, 89.8% female, 8676 with diagnosed T2DM) with a baseline BMD test (1996-2016), we estimated hazard ratios (HRs) for incident clinical fracture at different skeletal sites in those with compared to those without T2DM using Cox proportional hazards models over a mean (SD) 9.0 (5.0) year follow-up period. We also estimated odds ratios for prevalent vertebral fracture on VFA images amongst 9594 individuals (mean [SD] 76 [6.8] years, 1185 with T2DM diagnosis at time of DXA-VFA) and for prior clinical fractures at different skeletal sites using logistic regression models.

RESULTS

After multivariable adjustment, T2DM was associated with incident hip (HR 1.63, 95% CI 1.44 to 1.85) and proximal humerus fractures (HR 1.59, 95% CI 1.39 to 1.83), but was not associated with incident forearm fracture (HR 1.00, 95% CI 0.86 to 1.17) and only weakly with incident clinical vertebral fracture (HR 1.16, 95% CI 1.01 to 1.33). Similarly, T2DM was associated with prior hip (OR 1.78, 95% CI 1.21 to 2.61) and prior proximal humerus fracture (OR 1.31, 95% CI 1.02 to 1.68) but not with prior forearm (OR 0.89, 95% CI 0.74 to 1.06) or prevalent vertebral fracture on VFA images (OR 0.91, 95% CI 0.77 to 1.08).

CONCLUSION

T2DM is a stronger risk factor for hip and proximal humerus fractures than for vertebral and wrist fractures. Further research is warranted to determine if the known differences in falls and/or bone quality between T2DM and age-related osteoporosis account for these differential associations.

Radiographic diagnosis of osteoporotic vertebral fractures. An updated review

The radiological diagnosis of osteoporotic vertebral fractures (OVFs) is of major importance considering its therapeutic and prognostic implications. Both radiologists and clinicians have the opportunity to diagnose OVFs in daily clinical practice due to the widespread use of spine and chest radiography. However, several studies have reported an under-diagnosis of OVFs, particularly by a lack of consensus on the diagnostic criteria. Therefore, up-to-date knowledge of the most relevant approaches for the diagnosis of OVFs is necessary for many physicians. This article aims to review the most commonly used classification systems in the diagnosis of OVFs based on conventional radiography. We discuss their rationale, advantages and limitations, as well as their utility according to the context. This review will provide a concise yet useful understanding of the typology of OVFs, their clinical significance and prognosis. Finally, we include anatomical variations that can be confused with OVFs by non-experts.

Improving osteoporotic vertebral deformity detection on chest frontal view radiograph by adjusted X-ray beam positioning

Purpose

In clinics, chest frontal view radiograph (CFR) is often taken for patients suspected of respiratory diseases and for assessing the heart and big vessels. CFR can be utilised to opportunistically detect osteoporotic vertebral fracture (OVF). However, for standard CFR, the site of highest OVF prevalence, i.e., the thoracolumbar junction, is usually 'off-centre' to the X-ray beam focus. This study tested the hypothesis that, if a CRF is taken with approximately two vertebrae lower than the standard X-ray beam positioning, the visualization of thoraco-lumbar junction can be much improved.

Materials

Four hospitals (A, B, C, D) provided 101 elderly women's digital CFRs with standard filming (28, 20, 24, and 21 cases respectively). Eighty four elderly female patients were prospectively recruited from hospitals-A and B, who were consecutive patients referred for chest radiograph with indications other than spine disorders. For theses prospective CFRs, the focus of X-ray beam was adjusted from towards vertebra T6 to towards T8, and standard lateral radiographs were obtained for reference. Visibility of spine and detectability of OVF were assessed on the CFRs. OVF was diagnosed based on chest lateral radiograph (CLR) after excluding other potential causes both radiographically and clinically.

Results

For standardly filmed CFR, spine readability was similar among those from Hospitals-A, B, and C, while performed less well for those from Hospital-D. With the prospective cases from Hospitals-A and B, spines readable to vertebra L1 level or lower increased from 48.2% for standard filming to 80.7% for adjusted filming. Spines with 'blurry' labelling decreased from 35.7% for standard filming to 15.7% for adjusted filming. For the 84 prospective cases, 42.9% (36/84) of the patients had OVF, and 26 cases of CLR positive cases were detected as having vertebral deformity on CFR. For minimal OVF cases (<20% height loss), 38% (5/13) were detected on CFR. Among 22 cases with apparent OVF (≥20% height loss), two cases were missed on CFR. False positivity was labelled in five cases, among them four cases had 'burry' spines.

Conclusion

CFR can help opportunistically detect OVF, which can be further improved if X-ray beam is adjusted to towards vertebra T8 instead of towards vertebra T6.

The translational potential of this article

This study confirms that CFR can help detect OVF opportunistically, and the visibility of the mid/lower thoracic spine and thoracolumbar junction can be much improved after minor adjustment of X-ray beam positioning. This study also suggests high positive rate of OVF in elderly Chinese female patients indicated for chest radiograph. Radiologists should be trained and sensitized in vertebral deformity identification on CFR as the clinical management can be improved by opportunistic detection of OVF.

Associations of clinically recognized vs unrecognized vertebral fracture with mortality

PURPOSE

Our purpose was to contrast mortality associated with clinically undiagnosed prevalent vertebral fracture recognized on densitometric vertebral fracture assessment (VFA) and prior clinically diagnosed vertebral fracture.

METHODS

Between 2010 and 2016, 9679 men and women (mean age [SD] 76 [6.9] years, 93% women) with central site bone density T-score ≤ -1.5 had VFA images obtained at the time of bone densitometry. Vertebrae between T4 and L4 inclusive were evaluated for prevalent vertebral fracture on these images. Participants were categorized into three mutually exclusive groups; those with no vertebral fracture on VFA and no prior clinically diagnosed vertebral fracture (n = 7983), those with a definite vertebral fracture on VFA but no vertebral fracture clinically diagnosed before the index VFA date (n = 1376), and those with a prior clinically diagnosed vertebral fracture (n = 320). We ascertained mortality after the index VFA date using Manitoba provincial vital statistics files over a mean 2.8 (SD 1.7) years. We used Cox proportional hazards models to estimate the hazard ratios (HR) and 95% confidence intervals (C.I.) of prevalent vertebral fractures with mortality adjusted for multiple covariates.

RESULTS

Adjusted for age and sex, those with clinically undiagnosed vertebral fracture on VFA had an HR of 1.22 (95% C.I. 1.00 to 1.50) for mortality, and those with a prior clinically diagnosed vertebral fracture had an HR of 1.78 (95% C.I. 1.27 to 2.50) for mortality compared to those with no prevalent vertebral fracture. After further adjustment for comorbidity score, current smoking, and other causes of mortality, these associations were slightly attenuated (HRs 1.18 [95% C.I. 0.95 to 1.45] and of 1.70 [95% C.I. 1.21 to 2.40], respectively). Stratified by elapsed years since diagnosis, clinical vertebral fractures were associated with excess mortality for up to 10 years after their occurrence.

CONCLUSION

Clinically undiagnosed prevalent vertebral fracture detected on densitometric VFA images are weakly associated with subsequent mortality adjusted for age and sex, but not after accounting for other causes of mortality. Clinical vertebral fractures are associated with increased mortality for ten years after their diagnosis, even after accounting for other causes of mortality.

Combined radiomics-clinical model to predict malignancy of vertebral compression fractures on CT

OBJECTIVES

To develop and validate a combined radiomics-clinical model to predict malignancy of vertebral compression fractures on CT.

METHODS

One hundred sixty-five patients with vertebral compression fractures were allocated to training (n = 110 [62 acute benign and 48 malignant fractures]) and validation (n = 55 [30 acute benign and 25 malignant fractures]) cohorts. Radiomics features (n = 144) were extracted from non-contrast-enhanced CT images. Radiomics score was constructed by applying least absolute shrinkage and selection operator regression to reproducible features. A combined radiomics-clinical model was constructed by integrating significant clinical parameters with radiomics score using multivariate logistic regression analysis. Model performance was quantified in terms of discrimination and calibration. The model was internally validated on the independent data set.

RESULTS

The combined radiomics-clinical model, composed of two significant clinical predictors (age and history of malignancy) and the radiomics score, showed good calibration (Hosmer-Lemeshow test, p > 0.05) and discrimination in both training (AUC, 0.970) and validation (AUC, 0.948) cohorts. Discrimination performance of the combined model was higher than that of either the radiomics score (AUC, 0.941 in training cohort and 0.852 in validation cohort) or the clinical predictor model (AUC, 0.924 in training cohort and 0.849 in validation cohort). The model stratified patients into groups with low and high risk of malignant fracture with an accuracy of 98.2% in the training cohort and 90.9% in the validation cohort.

CONCLUSIONS

The combined radiomics-clinical model integrating clinical parameters with radiomics score could predict malignancy in vertebral compression fractures on CT with high discriminatory ability.

KEY POINTS

• A combined radiomics-clinical model was constructed to predict malignancy of vertebral compression fractures on CT by combining clinical parameters and radiomics features. • The model showed good calibration and discrimination in both training and validation cohorts. • The model showed high accuracy in the stratification of patients into groups with low and high risk of malignant vertebral compression fractures.

Interpretation of osteoporotic vertebral deformity on frontal view radiographs of the chest and abdomen: a pictorial review

Osteoporotic vertebral fracture (OVF) has high prevalence in the elderly population. It affects at least one-fourth of all postmenopausal women and is commonly seen among women approximately one decade after menopause. A vertebral fracture, after minor trauma, is a hallmark of osteoporosis. Many fractures and associated complications, including secondary fractures and mortality, can be prevented by routine osteoporosis screening in older people and timely treatment initiation in at-risk individuals. Depending on the technical condition of the radiographs, a substantial portion of moderate to severe grades OVFs in mid-thoracic and lower thoracic spine as well as lumbar spine can be detected on a frontal view digital radiograph of the chest or abdomen. Radiologists should pay attention to the potential existence of an OVF while reading chest and abdominal radiographs of elderly female subjects. In this pictorial review, we describe our experience in evaluating the normal shaped and deformed vertebrae on chest and abdominal radiographs.

The role of radiography in the study of spinal disorders

Despite the growing use of computed tomography (CT) and magnetic resonance imaging (MRI) in the study of spinal disorders, radiography still plays an important role in many conditions affecting the spine. However, the study and interpretation of spine radiograph is receiving less attention and radiologists are increasingly unfamiliar with the typical findings in normal and pathologic conditions of the spine. The aim of this article is to review the radiologic indications of radiograph in different pathologic conditions that affect the spine, including congenital, traumatic, degenerative, inflammatory, infectious and tumour disorders, as well as their main radiographic manifestations.

Diagnosis and grading of radiographic osteoporotic vertebral deformity by general radiologists after a brief self-learning period

Background

The expanded semi-quantitative (eSQ) osteoporotic vertebral deformity (OVD) classification has minimal, mild, moderate, moderately-severe, severe, and collapsed grades with <20%, 20–25%, >25%–1/3, >1/3–40%, >40%–2/3, >2/3 vertebral height loss respectively. This study evaluates the performance of using this grading criterion by radiology readers who did not have former training in OVD assessment.

Methods

Spine radiographs of 44 elderly women with 278 normal appearing vertebrae and 65 OVDs were selected, with two senior readers agreed the reference reading. Three readers from Italy and three readers from China were invited to evaluate these radiographs after reading five reference articles including one detailing eSQ criteria with illustrative examples. Before the second round of reading, the readers were asked to read an additional explanatory document. For the readers in Italy an additional on-line demonstration was given on how to measure vertebral height loss in another five cases of OVD. Two Chinese readers had a third round of reading after a 90 minutes’ on-line lecture.

Results

The final absolute agreement rate with the reference reading (i.e., exactly the same grading as the reference) ranged between 46.2% to 68.2% for the six readers, and the final relative agreement (with one eSQ grade difference allowed) ranged between 78.5% to 92.5%. The >1 grade disagreement rate was all below 11%, and mostly below 7%. The missed OVD were mostly minimal grade. The rate for missing a ≥ mild OVD was <4.5%, and false positive rate was generally <1.4% among the final reading. If the minimal grade was removed and the remaining gradings were converted to Genant’s semi-quantitative (GSQ) grading, the mean kappa values against the reference reading for SQ grades-1,2,3 were 0.813, 0.814, and 0.916 respectively.

Conclusions

This study demonstrates good performance of the six learner readers for assessing radiographic after a brief self-learning period.

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.

Targeted vertebral fracture assessment for optimizing fracture prevention in Canada

Vertebral fracture assessment (VFA) provides incremental information in identifying women and men aged 70 years and older qualifying for anti-osteoporosis treatment compared with FRAX^® major osteoporotic fracture (MOF) probability computed with bone mineral density (BMD).

PURPOSE

This analysis was performed to inform appropriate use of VFA testing as part of Osteoporosis Canada's Guidelines Update, assuming vertebral fracture is an indication for pharmacotherapy in women and men.

METHODS

Women and men aged 70 years and older without previous high-risk fracture (i.e., hip, spine, or multiple fractures) were identified in a BMD registry for the province of Manitoba, Canada. MOF probability with BMD was computed using the Canadian FRAX^® tool. VFA was performed in those with a minimum BMD T-score of -1.5 or lower.

RESULTS

The study population consisted of 7289 women (mean age 76.7 ± 5.6 years) and 1323 men (77.9 ± 5.8 years). More women than men qualified for VFA testing (48.7% vs 25.4%, respectively, p < 0.001). Among those undergoing VFA, a vertebral fracture was more commonly detected among men than women (22.9% vs 13.3%, p < 0.001), and vertebral fracture prevalence increased with lower BMD T-score (both p trend <0.001). The number needed to screen with VFA to detect a vertebral fracture was 8 for women and 4 for men. MOF probability was substantially lower in men than in women, and fewer men than women (3.3% vs 20.2%, p < 0.001) met a treatment threshold of MOF 20% or greater. In those with MOF probability <20%, VFA identified an incremental 5.4% of men and 3.4% of women for treatment based upon vertebral fracture.

CONCLUSIONS

The number needed to screen to identify a previously unappreciated vertebral fracture is low and further improves with lower BMD T-score. VFA identified more men as qualifying for treatment than MOF probability. In women, treatment qualification was predominantly from MOF probability.

Corrigendum to how to define an osteoporotic vertebral fracture

[This corrects the article DOI: 10.21037/qims.2019.09.10.].

Vertebral Fracture Assessment Increases Use of Pharmacologic Therapy for Fracture Prevention in Clinical Practice

The impact of vertebral fracture assessment (VFA) on lateral spine images in clinical practice on subsequent patient use of fracture prevention medication is unknown. Our objective was to determine the association of prevalent vertebral fracture identified on bone density lateral spine images (positive VFA) with subsequent use of fracture prevention therapy in usual clinical practice, using the Manitoba Bone Density Program database prospective observational cohort. Since 2010, targeted VFA imaging has been done at the time of bone densitometry in Manitoba for 21% of women and men meeting criteria based on age, bone mineral density (BMD), height loss, and glucocorticoid use. Among 6652 treatment-naive individuals with at least 90 days follow-up who had VFA imaging, 923 (13.9%) had one or more definite vertebral fractures identified using a modified algorithm-based qualitative (ABQ) method. For those with a positive VFA, their bone density reports stated the patient was at high risk of subsequent fracture and qualified for fracture prevention therapy. Subsequent osteoporosis treatment initiated within the next 12 months was identified using population-based pharmacy data. Logistic regression models were used to estimate the association of positive VFA with subsequent prescription (Rx), compared to negative VFA. Fracture prevention medication was started by 2127 (32%) individuals, 52.3% with positive versus 28.4% with negative VFA (p value <0.001). This association was substantially stronger in those designated (before VFA results were known) to have low or moderate fracture risk compared to high fracture risk (interaction p value <0.001), and in those with osteopenia (OR 4.51; 95% CI, 3.48 to 5.85) compared to those with osteoporosis by BMD criteria (OR 1.72; 95% CI, 1.43 to 2.08, interaction p value <0.001). Targeted VFA imaging at the time of bone densitometry substantially improves identification of those at high fracture risk and fracture prevention medication use among those with prevalent vertebral fracture. © 2019 American Society for Bone and Mineral Research. © 2019 American Society for Bone and Mineral Research.

How to define an osteoporotic vertebral fracture?

A vertebral deformity (VD) is not always a vertebral fracture (VF). Because of lack of a completely satisfactory "gold standard", there is no consensus on the exact definition of a VF. Therefore, it may sometimes be difficult, especially in mild cases, to discriminate the prevalent VF from a non-fracture deformity or short vertebral height (SVH). A combined standardized approach based on qualitative and semiquantitative (SQ) vertebral assessment may be the most option to correctly identify a VD as a VF. However this visual approach for VF identification is subjective, therefore it is mandatory an adequate training and experience of radiologist to reach a good sensitivity and specificity. Vertebral morphometry, objective and reproducible method, could be used only to evaluate the severity of VFs but requires the availability of reference values of vertebral height ratios. There is actually an evidentiary basis for suggesting that a qualitative approach by expert radiologists to morphological vertebral assessment, combined SQ and morphometric methods seem to be the preferred option for the correct diagnosis of VF as endplate or/and cortex fracture (ECF) or severe vertebral height loss.

Osteoporotic Vertebral Fracture Prevalence in Elderly Chinese Men and Women: A Comparison of Endplate/Cortex Fracture-Based and Morphometrical Deformity-Based Methods

This study aims to evaluate endplate/cortex fracture (ECF)-based method for detecting osteoporotic vertebral fracture (VF) in elderly Chinese population (age ≥ 65 years). The radiographs of 1954 elderly Chinese men (mean: 72.3 years) and 1953 elderly Chinese women (mean: 72.5 years) were evaluated according to Genant's morphometrical vertebral deformity (VD) severity criteria, as well as identified VF according to ECF without necessary requirement of VD. According to ECF, grade-1, -2, and -3 VF prevalence was 1.89%, 1.74%, and 2.25% in men, and 3.33%, 3.07%, and 5.89% in women, respectively. In men and women, 15.7% (35 of 223) and 34.5% (48 of 139) of vertebrae with VD grade-1 deformity were ECF(+, with fracture), respectively. In men and women, 89.7% (35 of 39) and 66.7% (48 of 72) of vertebrae with ECF grade-1 fracture had VD grade-1 deformity. For grade-1 change, ECF(+) subjects tended to have a lower BMD than the VD(+) subjects. In subjects with VD grade-2 deformity, those who were also EC (+) tended to have a lower BMD than those were ECF(-). In all grades, VD(-) and ECF(-) subjects tended to have highest BMD, whereas VD(+) and ECF(+) subjects tended to have lowest BMD. ECF may be more specific for assessing mild VF than the criteria based on vertebral deformity.

Prevalent vertebral fracture on bone density lateral spine (VFA) images in routine clinical practice predict incident fractures

PURPOSE

The predictive validity of vertebral fracture assessment (VFA) on bone density lateral spine images to identify prevalent vertebral fractures in routine clinical practice has not been established. Our objective was to estimate the associations of prevalent vertebral fracture identified on VFA images in routine practice with incident hip, all non-vertebral, major osteoporotic, and clinical vertebral fractures, using the Manitoba Bone Density database.

METHODS

From 2010 onward, 9972 men and women (mean age [SD] 76 [6.9] years) had VFA images obtained at the time of bone densitometry that were interpreted for vertebral fracture by the clinicians reading the bone density tests. Definite and possible prevalent vertebral fractures, respectively, were identified in 1575 (15.8%) and 293 (2.9%) using a modified Algorithm Based Qualitative method. We ascertained incident fractures using Manitoba provincial health databases over a mean 2.8 (SD 1.7) years and used Cox proportional hazards models to estimate the associations of prevalent vertebral fractures with incident fractures.

RESULTS

Compared to no prevalent vertebral fracture, those with definite prevalent vertebral fracture had higher hazard ratios for incident hip (HR 1.95, 95% C.I. 1.45 to 2.62), non-vertebral (HR 1.99, 95% C.I. 1.68 to 2.35), and clinical vertebral fracture (HR 2.68, 95% C.I. 1.69 to 4.23) adjusted for age, bone mineral density, body mass index, prior fracture, parental hip fracture, glucocorticoid use, alcohol use, smoking, and rheumatoid arthritis. These associations did not vary by FRAX fracture risk estimates or bone mineral density category.

CONCLUSION

Prevalent vertebral fractures identified on densitometric VFA images in routine clinical practice are strongly associated with incident fractures, and this study is the first to show this using any lateral spine imaging modality outside of research settings. These findings are strong evidence supporting the targeted use of densitometric VFA imaging among post-menopausal women and older men referred for bone densitometry.

Vertebral Fracture Identification as Part of a Comprehensive Risk Assessment in Patients with Osteoporosis

PURPOSE OF REVIEW

To review current evidence regarding the vertebral fracture prevalence, the accuracy of vertebral fracture identification on current imaging technologies, and the potential impact of vertebral fracture identification on fracture risk.

RECENT FINDINGS

Important new studies have clarified the features of prevalent vertebral fracture that most strongly predict incident fractures. Age- and sex-stratified estimates of vertebral fracture prevalence on densitometric lateral spine images in the US population are now available. The accuracy of densitometric vertebral fracture assessment, how computed tomography scans and other spinal images obtained for indications other than vertebral fracture assessment can be leveraged to detect prevalent vertebral fractures, and the potential impact of vertebral fracture assessment on patient and provider fracture risk management behavior have been clarified. Substantial progress has been made regarding screening strategies using lateral spine imaging to detect prevalent vertebral fracture in the older population. Further research regarding implementation of these strategies in clinical practice and their impact on clinical outcomes is needed.

Vertebral fracture assessment: Enhancing the diagnosis, prevention, and treatment of osteoporosis

Osteoporosis is a highly prevalent condition, resulting in significant morbidity and mortality. Nevertheless, it is frequently untreated. Vertebral fractures often do not come to clinical attention, yet, their presence is diagnostic of osteoporosis, helps to predict the risk of future fractures, and may alter the choice of pharmacotherapy. The addition of lateral spine imaging technology to the densitometer, for vertebral fracture assessment (VFA), represented a major advancement in the ability to diagnose vertebral fractures and osteoporosis. VFA is an under-utilized and highly effective imaging tool to enhance osteoporosis detection and fracture prevention. Several factors make VFA an ideal technology to evaluate for vertebral fractures. These include: the ability to obtain the image at the same time the bone density is done, with significantly lower radiation exposure than with spine radiography, and at a lower cost. This review provides an overview of the clinical significance of identifying vertebral fractures, the origins of the VFA, its clinical indications, a review of the methods used to diagnose vertebral fracture, an overview on interpreting the VFA, and the strengths and limitations of this technique.

Identifying osteoporotic vertebral endplate and cortex fractures

Osteoporosis is the most common metabolic bone disease, and vertebral fractures (VFs) are the most common osteoporotic fracture. A single atraumatic VF may lead to the diagnosis of osteoporosis. Prevalent VFs increase the risk of future vertebral and non-vertebral osteoporotic fracture independent of bone mineral density (BMD). The accurate and clear reporting of VF is essential to ensure patients with osteoporosis receive appropriate treatment. Radiologist has a vital role in the diagnosis of this disease. Several morphometrical and radiological methods for detecting osteoporotic VF have been proposed, but there is no consensus regarding the definition of osteoporotic VF. A vertebra may fracture yet not ever result in measurable changes in radiographic height or area. To overcome these difficulties, algorithm-based qualitative approach (ABQ) was developed with a focus on the identification of change in the vertebral endplate. Evidence of endplate fracture (rather than variation in vertebral shape) is the primary indicator of osteoporotic fracture according to ABQ criteria. Other changes that may mimic osteoporotic fractures should be systemically excluded. It is also possible that vertebral cortex fracture may not initially occur in endplate. Particularly, vertebral cortex fracture can occur in anterior vertebral cortex without gross vertebral deformity (VD), or fractures deform the anterior vertebral cortex without endplate disruption. This article aims to serve as a teaching material for physicians or researchers to identify vertebral endplate/cortex fracture (ECF). Emphasis is particularly dedicated to identifying ECF which may not be associated apparent vertebral body collapse. We believe a combined approach based on standardized radiologic evaluation by experts and morphometry measurement is the most appropriate approach to detect and classify VFs.