Radiologic assessment of osteoporotic vertebral fractures: diagnostic and prognostic implications

An overview of the performance of AI in fracture detection in lumbar and thoracic spine radiographs on a per vertebra basis

PURPOSE

Subtle spinal compression fractures can easily be missed. AI may help in interpreting these images. We propose to test the performance of an FDA-approved algorithm for fracture detection in radiographs on a per vertebra basis, assessing performance based on grade of compression, presence of foreign material, severity of degenerative changes, and acuity of the fracture.

METHODS

Thoracic and lumbar spine radiographs with inquiries for fracture were retrospectively collected and analyzed by the AI. The presence or absence of fracture was defined by the written report or cross-sectional imaging where available. Fractures were classified semi-quantitatively by the Genant classification, by acuity, by the presence of foreign material, and overall degree of degenerative change of the spine. The results of the AI were compared to the gold standard.

RESULTS

A total of 512 exams were included, depicting 4114 vertebra with 495 fractures. Overall sensitivity was 63.2% for the lumbar spine, significantly higher than the thoracic spine with 50.6%. Specificity was 96.7 and 98.3% respectively. Sensitivity increased with fracture grade, without a significant difference between grade 2 and 3 compression fractures (lumbar spine: grade 1, 52.5%; grade 2, 72.3%; grade 3, 75.8%; thoracic spine: grade 1, 42.4%; grade 2, 60.0%; grade 3, 60.0%). The presence of foreign material and a high degree of degenerative changes reduced sensitivity.

CONCLUSION

Overall performance of the AI on a per vertebra basis was degraded in clinically relevant scenarios such as for low-grade compression fractures.

Opportunistic Screening for Acute Vertebral Fractures on a Routine Abdominal or Chest Computed Tomography Scans Using an Automated Deep Learning Model

OBJECTIVES

To develop an opportunistic screening model based on a deep learning algorithm to detect recent vertebral fractures in abdominal or chest CTs.

MATERIALS AND METHODS

A total of 1309 coronal reformatted images (504 with a recent fracture from 119 patients, and 805 without fracture from 115 patients), from torso CTs, performed from September 2018 to April 2022, on patients who also had a spine MRI within two months, were included. Two readers participated in image selection and manually labeled the fractured segment on each selected image with Neuro-T (version 2.3.3; Neurocle Inc.) software. We split the images randomly into the training and internal test set (labeled: unlabeled = 480:700) and the secondary interval validation set (24:105). For the observer study, three radiologists reviewed the CT images in the external test set with and without deep learning assistance and scored the likelihood of an acute fracture in each image independently.

RESULTS

For the training and internal test sets, the AI achieved a 99.86% test accuracy, 91.22% precision, and 89.18% F1 score for detection of recent fracture. Then, in the secondary internal validation set, it achieved 99.90%, 74.93%, and 78.30%, respectively. In the observer study, with the assistance of the deep learning algorithm, a significant improvement was observed in the radiology resident's accuracy, from 92.79% to 98.2% (p = 0.04).

CONCLUSION

The model showed a high level of accuracy in the test set and also the internal validation set. If this algorithm is applied opportunistically to daily torso CT evaluation, it will be helpful for the early detection of fractures that require treatment.

Radiographic assessment of acute vs chronic vertebral compression fractures

PURPOSE

Distinguishing between acute and chronic vertebral compression fractures typically requires advanced imaging techniques such as magnetic resonance imaging (MRI). Recognizing specific radiographic findings associated with fracture acuity may improve the accuracy of radiographic assessment.

METHODS

Patients with compression fractures that had both radiographic and MRI studies of the lumbar spine within a 30-day time frame were retrospectively reviewed. MRI studies were used to determine compression fracture acuity. Radiographs were interpreted by a separate group of radiologists blinded to the MRI results. Radiographic findings of endplate osteophyte, subendplate density, subendplate cleft, and subendplate cyst were recorded as was the overall impression of fracture acuity.

RESULTS

Sensitivity and specificity for radiographic reporting of acute fracture were 0.52 (95% CI: 0.42, 0.61) and 0.95 (95% CI: 0.93, 0.97) respectively. For chronic fractures, the sensitivity and specificity were 0.52 (95% CI: 0.41, 0.63) and 0.94 (95% CI: 0.92, 0.96). The radiographic presence of a subendplate cleft increased the odds of a fracture being acute by a factor of 1.75 (95% CI: 1.09, 2.81; P = 0.0202). The radiographic presence of subendplate density increased the odds of a fracture being acute by a factor of 1.78 (95% CI: 1.21, 2.63; P = 0.0037). The presence of an endplate osteophyte or subendplate cyst was not significantly associated with fracture acuity.

CONCLUSION

Radiographs are relatively insensitive in distinguishing between acute and chronic lumbar compression fractures but the presence of a subendplate cleft or subendplate density increases the likelihood that a given fracture is acute.

Epidemiology and reporting of osteoporotic vertebral fractures in patients with long-term hospital records based on routine clinical CT imaging

Osteoporotic vertebral fractures signify an increased risk of future fractures and mortality and can manifest the diagnosis of osteoporosis. We investigated the prevalence of vertebral fractures in routine CT of patients with long-term hospital records. Three out of ten patients showed osteoporotic vertebral fractures (VFs) corresponding to the highest rates reported in European population-based studies.

INTRODUCTION

VFs are a common manifestation of osteoporosis, which influences future fracture risk. Their epidemiology has been investigated in population-based studies. However, few studies report the prevalence of osteoporotic VF in patients seen in clinical routine and include all common fracture levels of the thoracolumbar spine. The purpose of this study was to investigate the prevalence of osteoporotic VF in patients with CT scans and long-term hospital records and identify clinical factors associated with prevalent VFs.

METHODS

All patients aged 45 years and older with a CT scan and prior hospital record of at least 5 years that were seen in the study period between September 2008 and May 2017 were reviewed. Imaging requirements were a CT scan with sagittal reformations including at least T6-L4. Patients with multiple myeloma were excluded. Fracture reading was performed using the Genant semi-quantitative method. Medical notes were reviewed for established diagnoses of osteoporosis and clinical information. Clinical factors (e.g. drug intake, chemotherapy, and mobility level) associated with prevalent VF were identified in logistic regression.

RESULTS

The study population consisted of 718 patients (228 women and 490 men; mean age 69.3 ± 10.1 years) with mainly cancer staging and angiography CT imaging. The overall prevalence of VFs was 30.5%, with non-significantly more men showing a fracture (32.5%) compared to women (26.3%; p > 0.05). Intake of metamizole for ≥ 3 months was significantly associated with a prevalent VF. Medical records did not include information about bone health in 90% of all patients. CT reports did mention a VF in only 24.7% of patients with a prevalent VF on CT review.

CONCLUSION

Approximately 30% of elderly patients with CT imaging and long-term hospital records showed VFs. Only one-quarter of these patients had VFs mentioned in CT reports. Osteoporosis management could be improved by consequent reporting of VFs in CT, opportunistic bone density measurements, and early involvement of fracture liaison services.

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.

Differential diagnosis between metastatic and osteoporotic vertebral fractures using sagittal T1-weighted magnetic resonance imaging

BACKGROUND

Magnetic resonance imaging (MRI) is the most helpful for determining the differential diagnosis between metastatic and osteoporotic vertebral fractures; especially whole spine MRI is effective if patients have multiple spinal metastases. However, it is time-consuming to obtain all planes for all metastatic vertebrae. If we can differentiate these metastatic and osteoporotic vertebral fractures based on only one section and signal intensity, it would save time and be effective for patients with pain. This study investigated the usefulness of sagittal T1-weighted MRI findings in differentiating metastatic and osteoporotic vertebral fractures.

METHODS

We retrospectively reviewed patients diagnosed with metastatic or osteoporotic vertebral fractures. Findings characteristic of metastatic fractures were considered: (a) pedicle or posterior element involvement; (b) convex posterior border of the vertebral body; (c) epidural infiltration; and (d) diffuse homogeneous low signal intensity; findings characteristic of osteoporotic compression fractures were also considered: (e) low-signal-intensity band and (f) posterior retropulsion. Chi-square test or Fisher's exact probability test was used to investigate the usefulness of each MRI finding. Intra- and inter-observer reliability analysis was performed.

RESULTS

This study comprised 43 patients with metastases (45 vertebrae) and 118 patients with osteoporotic fractures (156 vertebrae). All findings showed significant difference with each fracture (p-value: <0.01 to 0.03). Although each MRI finding exhibited high intra- and inter-observer reliability (κ: 0.66 to 1.00), finding (c) exhibited low reliability. Finding (a) showed high sensitivity (88.9%) and usefulness for screening, and findings (b), (d), (e), and (f) showed high specificity (90.4%-100%) and usefulness for definitive diagnosis.

CONCLUSIONS

Characteristic findings with sagittal T1-weighted MRI were useful in the differential diagnosis of metastatic and osteoporotic vertebral fractures. To prevent overlooking metastatic fractures with sagittal T1-weighted MRI, findings of the pedicle or posterior element involvement should be focused on because of its reliability and sensitivity.

Combined intravoxel incoherent motion diffusion-weighted MR imaging and magnetic resonance spectroscopy in differentiation between osteoporotic and metastatic vertebral compression fractures

Purpose

Our purpose was to combine intravoxel incoherent motion diffusion-weighted MR imaging (IVIM-DWI) and magnetic resonance spectroscopy (MRS) to differentiate osteoporotic fractures from osteolytic metastatic vertebral compression fractures (VCFs).

Methods

A total of 70 patients with VCFs were included and divided into two groups, according to their causes of fractures based on pathological findings or clinical follow-up. All patients underwent conventional sagittal T1WI, T2WI, STIR, IVIM-DWI, and single-voxel MRS. The diffusion coefficient (D), pseudo diffusion (D*), and perfusion fraction (f) parameters from IVIM-DWI and the lipid water ratio (LWR) and fat fraction (FF) parameters from MRS were obtained and compared among groups. Furthermore, the diagnostic performance of MRS, IVIM-DWI, and IVIM-DWI combined with MRS for differentiation between osteoporotic and osteolytic metastatic VCFs was assessed by using receiver operating characteristic (ROC) curve analysis.

Results

Compared with the osteoporotic group, the metastatic group had significantly lower values for f, D, and FF, but higher D* (all P < 0.05). The area under the receiver operating characteristic (ROC) curve of MRS, IVIM-DWI, and IVIM-DWI combined with MRS were 0.73, 0.88, and 0.94, respectively. Among these, the IVIM-DWI combined with MRS showed the highest sensitivity, specificity, and accuracy, which are 90.63% (29/32), 97.37 % (37/38), and 94.29% (66/70), respectively.

Conclusions

IVIM-DWI combined with MRS can be more accurate and efficient for differentiation between osteoporotic and osteolytic metastatic VCFs than single MRS or IVIM-DWI.

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.

Diagnosis of osteoporotic vertebral fractures in children

Osteoporosis is a generalised disorder of the skeleton with reduced bone density and abnormal bone architecture. It increases bone fragility and renders the individual susceptible to fractures. Fractures of the vertebrae are common osteoporotic fractures. Vertebral fractures may result in scoliosis or kyphosis and, because they may be clinically silent, it is imperative that vertebral fractures are diagnosed in children accurately and at an early stage, so the necessary medical care can be implemented. Traditionally, diagnosis of osteoporotic vertebral fractures has been from lateral spine radiographs; however, a small number of studies have shown that dual energy x-ray absorptiometry is comparable to radiographs for identifying vertebral fractures in children, while allowing reduced radiation exposure. The diagnosis of vertebral fractures from dual energy x-ray absorptiometry is termed vertebral fracture assessment. Existing scoring systems for vertebral fracture assessment in adults have been assessed for use in children, but there is no standardisation and observer reliability is variable. This literature review suggests the need for a semiautomated tool that (compared to the subjective and semiquantitative methods available) will allow more reliable and precise detection of vertebral fractures in children.

Proton density fat fraction (PDFF) MR imaging for differentiation of acute benign and neoplastic compression fractures of the spine

OBJECTIVES

To evaluate the diagnostic performance of proton density fat fraction (PDFF) magnetic resonance imaging (MRI) to differentiate between acute benign and neoplastic vertebral compression fractures (VCFs).

METHODS

Fifty-seven consecutive patients with 46 acute benign and 41 malignant VCFs were prospectively enrolled in this institutional review board approved study and underwent routine clinical MRI with an additional six-echo modified Dixon sequence of the spine at a clinical 3.0-T scanner. All fractures were categorised as benign or malignant according to either direct bone biopsy or 6-month follow-up MRI. Intravertebral PDFF and PDFF_ratio (fracture PDFF/normal vertebrae PDFF) for benign and malignant VCFs were calculated using region-of-interest analysis and compared between both groups. Additional receiver operating characteristic and binary logistic regression analyses were performed.

RESULTS

Both PDFF and PDFF_ratio of malignant VCFs were significantly lower compared to acute benign VCFs [PDFF, 3.48 ± 3.30% vs 23.99 ± 11.86% (p < 0.001); PDFF_ratio, 0.09 ± 0.09 vs 0.49 ± 0.24 (p < 0.001)]. The areas under the curve were 0.98 for PDFF and 0.97 for PDFF_ratio, yielding an accuracy of 96% and 95% for differentiating between acute benign and malignant VCFs. PDFF remained as the only imaging-based variable to independently differentiate between acute benign and malignant VCFs on multivariate analysis (odds ratio, 0.454; p = 0.005).

CONCLUSIONS

Quantitative assessment of PDFF derived from modified Dixon water-fat MRI has high diagnostic accuracy for the differentiation of acute benign and malignant vertebral compression fractures.

KEY POINTS

• Chemical-shift-encoding based water-fat MRI can reliably assess vertebral bone marrow PDFF • PDFF is significantly higher in acute benign than in malignant VCFs • PDFF provides high accuracy for differentiating acute benign from malignant VCFs.

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.

Quantitative imaging methods in osteoporosis

Osteoporosis is characterized by a decreased bone mass and quality resulting in an increased fracture risk. Quantitative imaging methods are critical in the diagnosis and follow-up of treatment effects in osteoporosis. Prior radiographic vertebral fractures and bone mineral density (BMD) as a quantitative parameter derived from dual-energy X-ray absorptiometry (DXA) are among the strongest known predictors of future osteoporotic fractures. Therefore, current clinical decision making relies heavily on accurate assessment of these imaging features. Further, novel quantitative techniques are being developed to appraise additional characteristics of osteoporosis including three-dimensional bone architecture with quantitative computed tomography (QCT). Dedicated high-resolution (HR) CT equipment is available to enhance image quality. At the other end of the spectrum, by utilizing post-processing techniques such as the trabecular bone score (TBS) information on three-dimensional architecture can be derived from DXA images. Further developments in magnetic resonance imaging (MRI) seem promising to not only capture bone micro-architecture but also characterize processes at the molecular level. This review provides an overview of various quantitative imaging techniques based on different radiological modalities utilized in clinical osteoporosis care and research.

Shape, texture and statistical features for classification of benign and malignant vertebral compression fractures in magnetic resonance images

PURPOSE

Vertebral compression fractures (VCFs) result in partial collapse of vertebral bodies. They usually are nontraumatic or occur with low-energy trauma in the elderly secondary to different etiologies, such as insufficiency fractures of bone fragility in osteoporosis (benign fractures) or vertebral metastasis (malignant fractures). Our study aims to classify VCFs in T1-weighted magnetic resonance images (MRI).

METHODS

We used the median sagittal planes of lumbar spine MRIs from 63 patients (38 women and 25 men) previously diagnosed with VCFs. The lumbar vertebral bodies were manually segmented and statistical features of gray levels were computed from the histogram. We also extracted texture and shape features to analyze the contours of the vertebral bodies. In total, 102 lumbar VCFs (53 benign and 49 malignant) and 89 normal lumbar vertebral bodies were analyzed. The k-nearest-neighbor method, a neural network with radial basis functions, and a naïve Bayes classifier were used with feature selection. We compared the classification obtained by these classifiers with the final diagnosis of each case, including biopsy for the malignant fractures and clinical and laboratory follow up for the benign fractures.

RESULTS

The results obtained show an area under the receiver operating characteristic curve of 0.97 in distinguishing between normal and fractured vertebral bodies, and 0.92 in discriminating between benign and malignant fractures.

CONCLUSIONS

The proposed classification methods based on shape, texture, and statistical features have provided high accuracy and may assist in the diagnosis of VCFs.

Dual-Energy X-Ray Absorptiometry: Beyond Bone Mineral Density Determination

Significant improvements in dual-energy X-ray absorptiometry (DXA) concerning quality, image resolution and image acquisition time have allowed the development of various functions. DXA can evaluate bone quality by indirect analysis of micro- and macro-architecture of the bone, which and improve the prediction of fracture risk. DXA can also detect existing fractures, such as vertebral fractures or atypical femur fractures, without additional radiologic imaging and radiation exposure. Moreover, it can assess the metabolic status by the measurement of body composition parameters like muscle mass and visceral fat. Although more studies are required to validate and clinically use these parameters, it is clear that DXA is not just for bone mineral densitometry.

Opportunistic Identification of Vertebral Fractures

Vertebral fractures are powerful predictors of future fracture, so, their identification is important to ensure that patients are commenced on appropriate bone protective or bone-enhancing therapy. Risk factors (e.g., low bone mineral density and increasing age) and symptoms (back pain, loss of height) may herald the presence of vertebral fractures, which are usually confirmed by performing spinal radiographs or, increasingly, using vertebral fracture assessment with dual-energy X-ray absorptiometry scanners. However, a large number (30% or more) of vertebral fractures are asymptomatic and do not come to clinical attention. There is, therefore, scope for opportunistic (fortuitous) identification of vertebral fractures from various imaging modalities (radiographs, computed tomography, magnetic resonance imaging, and radionuclide scans) performed for other clinical indications and which include the spine in the field of view, with midline sagittal reformatted images from computed tomography having the greatest potential for such opportunistic detection. Numerous studies confirm this potential for identification but consistently find underreporting of vertebral fractures. So, a valuable opportunity to improve the management of patients at increased risk of future fracture is being squandered. Educational training programs for all clinicians and constant reiteration, stressing the importance of the accurate and clear reporting of vertebral fractures ("you only see what you look for"), can improve the situation, and automated computer-aided diagnostic tools also show promise to solve the problem of this underreporting of vertebral fractures.

Osteoporotic Fracture: 2015 Position Statement of the Korean Society for Bone and Mineral Research

Osteoporotic fractures are one of the most common causes of disability and a major contributor to medical care costs worldwide. Prior osteoporotic fracture at any site is one of the strongest risk factors for a new fracture, which occurs very soon after the first fracture. Bone mineral density (BMD) scan, a conventional diagnostic tool for osteoporosis, has clear limitations in diagnosing osteoporotic fractures and identifying the risk of subsequent fractures. Therefore, early and accurate diagnosis of osteoporotic fractures using the clinical definition which is applicable practically and independent of BMD, is essential for preventing subsequent fractures and reducing the socioeconomic burden of these fractures. Fractures caused by low-level trauma equivalent to a fall from a standing height or less at major (hip, spine, distal radius, and proximal humerus) or minor (pelvis, sacrum, ribs, distal femur and humerus, and ankle) sites in adults over age 50, should be first regarded as osteoporotic. In addition, if osteoporotic fractures are strongly suspected on history and physical examination even though there are no positive findings on conventional X-rays, more advanced imaging techniques such as computed tomography, bone scan, and magnetic resonance imaging are necessary as soon as possible.

Imaging Findings and Evaluation of Metabolic Bone Disease

Bone is a dynamic organ of the endoskeleton, playing an important role in structural integrity, mineral reservoirs, blood production, coagulation, and immunity. Metabolic bone disease encompasses a broad spectrum of inherited and acquired disorders that disrupt the normal homeostasis of bone formation and resorption. For patients affected by these processes, radiologic imaging plays a central role in diagnosis, monitoring treatment, and risk stratification. Radiologists should be familiar with the diseases, intimately aware of the imaging findings, and possessive of multimodality expertise to wisely guide the best practice of medicine. The purpose of this paper is to review the imaging features and characteristics of the most common types of metabolic bone disease with highlights of clinically relevant information so that readers can better generate appropriate differential diagnoses and recommendations. For this review, a thorough literature search for the most up-to-date information was performed on several key types of metabolic bone disease: osteoporosis, osteomalacia, rickets, scurvy, renal osteodystrophy, hyperparathyroidism, Paget’s disease, osteogenesis imperfecta, acromegaly, and osteopetrosis. Although they all affect the bone, these diseases have both shared characteristic features that can be discerned through imaging.

[Differentiation between acute osteoporotic and metastatic vertebral body fractures by imaging]

OBJECTIVES

This article discusses the morphological criteria for the differentiation between acute osteoporotic and metastatic vertebral body fractures and new imaging methods, such as diffusion-weighted and chemical shift magnetic resonance imaging (MRI) are presented.

BACKGROUND

The differential diagnostics of osteoporotic and metastatic vertebral body fractures can be difficult in some cases. Both entities normally occur without adequate trauma and predominantly in elderly patients.

IMAGING

Conventional X-ray examination is the initial imaging method of choice but is not able to reliably differentiate between the osteoporotic or metastatic etiology of a fracture. Computed tomography (CT) clearly depicts osseous destruction in metastatic fractures but lacks specificity. Magnetic resonance imaging (MRI) shows a higher sensitivity and specificity in differentiating osteoporotic and metastatic fractures.

DIFFERENTIAL DIAGNOSTICS

The combination CT and MRI allows an accurate diagnosis with respect to an osteoprorotic or metastatic etiology in most of cases but bone marrow edema in acute fractures sometimes leads to ambiguous results and differential diagnostic problems.

Reconsideration of the relevance of mild wedge or short vertebral height deformities across a broad age distribution

Based on an evaluation of vertebral fracture prevalence on lateral radiographs across all age groups in a large cohort, mild or wedge-shaped vertebral body changes identified among adults should be managed as osteoporosis or at least considered as a risk factor for osteoporotic fracture, since they are rare among young subjects.

INTRODUCTION

Radiographic assessment of vertebral fractures is limited by the inability to distinguish mild fractures from congenital mild wedge deformities or vertebrae of short vertebral height. We attempted to quantify the expected background prevalence of these deformities by measuring vertebral fracture prevalence across all age groups in a large hospital-based retrospective Chinese cohort.

METHODS

We reviewed eligible lateral chest radiographs from patients admitted to Peking Union Medical College Hospital during 2011 using the Genant semiquantitative method for vertebral fracture assessment (T4-L2). We evaluated fracture prevalence among subjects by sex, 10-year age group, and fracture severity grades subjectively. We further analyzed characteristics of subjects with mild (grade I) fractures to estimate the relative contribution of congenital mild wedge deformities.

RESULTS

A total of 10,720 subjects (5,396 men and 5,324 women) with lateral chest radiographs were evaluated. Subjects ranged in age from 0.5 to 97 years with a mean of 51.8 ± 17.4 years (men 52.8 ± 17.6 years; women 50.8 ± 17.2 years). When stratified by 10-year age groups, the prevalence of vertebral fractures was relatively low until about 40 years of age, after which prevalence increased for both genders. Fractures (13 fractures for 9 males and 6 fractures for 5 females) seen in subjects younger than 40 years of age were almost exclusively mild grade fractures. No fractures were identified in subjects younger than 20 years of age.

CONCLUSIONS

Mild or wedge-shaped vertebral body changes on lateral radiographs are rare among young subjects, indicating that when mild vertebral deformities are found among adults, they are likely to be the product of aging and not congenital variation. Clinically, therefore, mild vertebral body changes should be managed as osteoporosis or at least considered as a risk factor for osteoporotic fracture.

Is balloon kyphoplasty better than percutaneous vertebroplasty for osteoporotic vertebral biconcave-shaped fractures?

BACKGROUND

Osteoporotic vertebral biconcave-shaped fractures are not commonly seen in clinical practice. Some articles have been published showing the outcome of vertebroplasty (PV) and balloon kyphoplasty (BKP), but few comparative studies have been performed.

PURPOSE

To compare the effect and safety of PV and BKP in treating osteoporotic vertebral biconcave-shaped fractures.

MATERIAL AND METHODS

In this retrospective comparative study, 38 patients with osteoporotic vertebral biconcave-shaped fractures were treated by PV, and 41 patients were treated by BKP from May 2005 to July 2011. The heights of the compromised vertebral body and the kyphotic angles were measured. Visual analogue scale (VAS) and Oswestry Disability Index (ODI) were used to evaluate pain and functional activity, respectively. The occurrence of refracture and cement leakage were determined, and the costs were recorded.

RESULTS

The mean VAS and ODI scores significantly improved for both procedures at postsurgical measurements (P < 0.05), and the improvement sustained at the final follow-up. In both groups, there were no significant differences in terms of restoration of the anterior vertebral height and correction of the kyphotic deformity. However, BKP was more effective in restoring the middle vertebral height than PV. Cement leakages were observed in nine (23.7%) treated vertebral bodies in PV group and in three (7.4%) treated vertebral bodies in BKP group, which was a statistically significant difference (P < 0.05). There were four new osteoporotic vertebral fractures in the PV group and two in the BKP group during the follow-up period. The mean cost in the BKP group (6200 ± 122.1 USD) was higher than the PV group (2100 ± 112.5 USD) (P < 0.05).

CONCLUSION

Both PV and BKP achieved similar improvements in pain and functional outcomes for the treatment of osteoporotic vertebral biconcave-shaped fractures. BKP had a significant advantage over PV in terms of the restoration of the middle vertebral height and fewer cement leakages than PV.

Osteoporosis and fragility fractures: Vertebral fractures

The incidence of vertebral fragility fractures and deformity increase steeply with age. Every sixth woman and every twelfth man will sustain a symptomatic vertebral fracture. Vertebral fractures result in pain, functional disability and decreased quality of life, which may last for several years, and may also affect mortality. The patient with an acute fracture should be examined with radiology for diagnosis. In case of a low-energy fracture, osteoporosis should be suspected and investigated. If the pain management fails, vertebroplasty or kyphoplasty could be considered. Braces may be used, but evidence for its effect is lacking. In the rare event of neurological compromise, or unstable fractures, surgical treatment should be considered. After vertebral fragility fractures, the risk for new fractures is high and secondary preventive measures advocated. The best evidence for secondary prevention is currently on medical treatment of osteoporosis.

Imaging of vertebral fractures

Vertebral fracture is a common clinical problem. Osteoporosis is the leading cause of non-traumatic vertebral fracture. Often, vertebral fractures are not clinically suspected due to nonspecific presentation and are overlooked during routine interpretation of radiologic investigations. Moreover, once detected, many a times the radiologist fails to convey to the clinician in a meaningful way. Hence, vertebral fractures are a constant cause of morbidity and mortality. Presence of vertebral fracture increases the chance of fracture in another vertebra and also increases the risk of subsequent hip fracture. Early detection can lead to immediate therapeutic intervention improving further the quality of life. So, in this review, we wish to present a comprehensive overview of vertebral fracture imaging along with an algorithm of evaluation of vertebral fractures.

Efficacy of the dynamic radiographs for diagnosing acute osteoporotic vertebral fractures

We investigated the efficacy of dynamic radiographs for diagnosing acute osteoporotic vertebral fractures (OVFs) compared with supine radiographs or sitting radiographs alone. Evaluation of the dynamic radiographs was superior to the other evaluations. Dynamic radiographs provide a convenient and useful method of diagnosing acute OVFs.

INTRODUCTION

Identifying acute OVFs on plain radiographs is difficult. We studied a new approach to identify acute OVFs on the basis of fracture mobility.

METHODS

We performed a retrospective radiographic analysis of 472 acute OVFs (<3 weeks after onset), which were diagnosed on the basis of magnetic resonance imaging of T5 through L5 (a total of 5,239 vertebrae). Supine lateral radiographs were compared with sitting lateral radiographs to determine the presence or absence of mobility. Vertebrae showing changes in the vertebral body height were diagnosed as acute OVFs. We analyzed the diagnostic accuracy on the basis of comparative supine and sitting lateral radiographs and compared it with that of radiographs obtained in the supine or the sitting position alone.

RESULTS

Of the 472 acute OVFs diagnosed, 313 (66 %) exhibited vertebral mobility on supine lateral and sitting lateral radiographs. Correct diagnoses of acute OVFs or no acute OVFs were made in 4,883 vertebrae. There were 159 unreadable OVFs (3 %), and 197 previous OVFs (4 %) were misdiagnosed as acute OVFs. The sensitivity was 66 % and the specificity was 96 %. Evaluation of the mobility of acute OVFs in the supine and the sitting position was superior to evaluation using radiographs in either the supine or the sitting position alone.

CONCLUSIONS

Dynamic radiographs provide a convenient way to identify acute OVFs.

Early diagnosis of vertebral fractures

Vertebral fractures are a common clinical entity, caused by trauma or related to osteoporosis (benign). Their recognition is especially important in the post-menopausal female population but also important is their differentiation from pathological (malignant) fractures (1). A vertebral fracture is evidenced by vertebral body deformity or reduction in vertebral body height beyond a certain threshold value in the absence of bone discontinuity. For prognosis and treatment it is extremely important to recognize the cause of the fracture. In contrast to fractures that occur in other locations, vertebral fractures often go unrecognized in the acute phase as the pain may be transient and radiographic and evaluation of the spine may be difficult (2). Objective measurement of the vertebral deformity provides invaluable information to the interpreting physician and helps grade fracture severity. The recognition and diagnosis of vertebral fractures can be performed using additional diagnostic tools.

Advances in bone imaging for osteoporosis

The diagnosis and management of osteoporosis have been improved by the development of new quantitative methods of skeletal assessment and by the availability of an increasing number of therapeutic options, respectively. A number of imaging methods exist and all have advantages and disadvantages. Dual-energy X-ray absorptiometry (DXA) is the most widely available and commonly utilized method for clinical diagnosis of osteoporosis and will remain so for the foreseeable future. The WHO 10-year fracture risk assessment tool (FRAX(®)) will improve clinical use of DXA and the cost-effectiveness of therapeutic intervention. Improved reporting of radiographic features that suggest osteoporosis and the presence of vertebral fracture, which are powerful predictors of future fractures, could increase the frequency of appropriate DXA referrals. Quantitative CT remains predominantly a research tool, but has advantages over DXA--allowing measurement of volumetric density, separate measures of cortical and trabecular bone density, and evaluation of bone shape and size. High resolution imaging, using both CT and MRI, has been introduced to measure trabecular and cortical bone microstructure. Although these methods provide detailed insights into the effects of disease and therapies on bone, they are technically challenging and not widely available, so they are unlikely to be used in clinical practice.

Supine vs decubitus lateral patient positioning in vertebral fracture assessment

In vertebral fracture assessment (VFA), lateral scans are obtained with the patient positioned supine (C-arm densitometers) or lateral decubitus (fixed-arm densitometers). We aimed to determine the impact of positioning on image quality and fracture definition. We performed supine and decubitus lateral VFA in 50 postmenopausal women and used the algorithm-based qualitative method to identify vertebral fractures. We compared the 2 techniques for the identification of fractures (kappa analysis) and compared the numbers of unreadable vertebrae (indiscernible endplates) and vertebrae that were projected obliquely (Wilcoxon matched-pairs signed-rank test). The kappa score for agreement between the VFA techniques (to identify women with vertebral fractures) was 0.84 (95% confidence interval [CI]: 0.68-0.99), and for agreement with fracture assessments made from radiographs, kappa was 0.76 (95% CI: 0.57-0.94) for both supine and decubitus lateral VFA. There were more unreadable vertebrae with supine lateral (48 vertebrae in supine lateral compared with 14 in decubitus lateral; p=0.001), but oblique projection was less common (93 vertebrae compared with 145 in decubitus lateral; p=0.002). We conclude that there were significantly different projection effects with supine and decubitus lateral VFA, but these differences did not influence the identification of vertebral fractures in our study sample.

Imaging of stress fractures of the spine

Back pain caused by stress fractures, fatigue, or insufficiency, affects varied patient populations based on the level of physical activity and bone mineral density. Stress fractures may involve the vertebral body, pars interarticularis, and the pedicle; often overlooked are stress fractures of the sacrum or bony pelvis, which can mimic pain of spinal origin and delay diagnosis. The choice of optimal imaging (radiographs, nuclear medicine, magnetic resonance imaging, and computed tomography) also depends on the patient population under study and the clinically suspected diagnosis. The diagnosis typically determines which imaging modality is best to follow healing or progression.

The importance of morphometric radiographic vertebral assessment for the detection of patients who need pharmacological treatment of osteoporosis among postmenopausal diabetic Korean women

Many diabetic patients with vertebral fractures remain undiagnosed and untreated. We found that more than two-thirds of osteoporotic diabetic women could not be identified for pharmacological treatment according to the NOF guidelines if without radiographic vertebral assessment. This study shows the importance of radiographic vertebral assessment for identifying patients who need treatment for osteoporosis in diabetic women.

INTRODUCTION

Diagnosis of vertebral fracture (VF) is important for identifying patients who need pharmacologic therapy for osteoporosis. However, many patients with vertebral fractures remain undiagnosed and untreated. This study evaluated the number of patients with VFs who would be unrecognized as candidates for osteoporosis treatments according to the National Osteoporosis Foundation (NOF) Clinician’s Guidelines to the Treatment of Osteoporosis, among postmenopausal diabetic Korean women without spinal imaging.

METHODS

A total of 873 postmenopausal diabetic women were enrolled. Lateral plain radiographs of the thoracolumbar spine and total hip BMD were obtained. The Fracture Risk Assessment Tool (FRAX®) probability was computed using the algorithm available online at http://www.shef.ac.uk/FRAX (South Korea version). The subjects with and without VFs were classified into candidates for osteoporosis treatment [Tx+by NOF] and not candidates for osteoporosis treatment [Tx−by NOF] according to the NOF pharmacologic treatment guidelines, regardless of the presence of VFs.

RESULTS

Forty-six percent of postmenopausal diabetic womenhad morphometric VFs. Among the subjects with morphometric VFs, only 2% of the patients had previously diagnosed VFs by medical doctors. In addition, 73.6% of the patients with VFs were not included in the [Tx+by NOF] group, given the assumption of no radiographic diagnosis of VFs.

CONCLUSIONS

With regard to increased risk of VFs in postmenopausal Korean women with type 2 diabetes mellitus, radiographic vertebral assessment would be useful for the clinical identification of osteoporosis and fractures.

Osteoporosis imaging: state of the art and advanced imaging

Osteoporosis is becoming an increasingly important public health issue, and effective treatments to prevent fragility fractures are available. Osteoporosis imaging is of critical importance in identifying individuals at risk for fractures who would require pharmacotherapy to reduce fracture risk and also in monitoring response to treatment. Dual x-ray absorptiometry is currently the state-of-the-art technique to measure bone mineral density and to diagnose osteoporosis according to the World Health Organization guidelines. Motivated by a 2000 National Institutes of Health consensus conference, substantial research efforts have focused on assessing bone quality by using advanced imaging techniques. Among these techniques aimed at better characterizing fracture risk and treatment effects, high-resolution peripheral quantitative computed tomography (CT) currently plays a central role, and a large number of recent studies have used this technique to study trabecular and cortical bone architecture. Other techniques to analyze bone quality include multidetector CT, magnetic resonance imaging, and quantitative ultrasonography. In addition to quantitative imaging techniques measuring bone density and quality, imaging needs to be used to diagnose prevalent osteoporotic fractures, such as spine fractures on chest radiographs and sagittal multidetector CT reconstructions. Radiologists need to be sensitized to the fact that the presence of fragility fractures will alter patient care, and these fractures need to be described in the report. This review article covers state-of-the-art imaging techniques to measure bone mineral density, describes novel techniques to study bone quality, and focuses on how standard imaging techniques should be used to diagnose prevalent osteoporotic fractures.

Osteoporosis imaging: state of the art and advanced imaging

Osteoporosis is becoming an increasingly important public health issue, and effective treatments to prevent fragility fractures are available. Osteoporosis imaging is of critical importance in identifying individuals at risk for fractures who would require pharmacotherapy to reduce fracture risk and also in monitoring response to treatment. Dual x-ray absorptiometry is currently the state-of-the-art technique to measure bone mineral density and to diagnose osteoporosis according to the World Health Organization guidelines. Motivated by a 2000 National Institutes of Health consensus conference, substantial research efforts have focused on assessing bone quality by using advanced imaging techniques. Among these techniques aimed at better characterizing fracture risk and treatment effects, high-resolution peripheral quantitative computed tomography (CT) currently plays a central role, and a large number of recent studies have used this technique to study trabecular and cortical bone architecture. Other techniques to analyze bone quality include multidetector CT, magnetic resonance imaging, and quantitative ultrasonography. In addition to quantitative imaging techniques measuring bone density and quality, imaging needs to be used to diagnose prevalent osteoporotic fractures, such as spine fractures on chest radiographs and sagittal multidetector CT reconstructions. Radiologists need to be sensitized to the fact that the presence of fragility fractures will alter patient care, and these fractures need to be described in the report. This review article covers state-of-the-art imaging techniques to measure bone mineral density, describes novel techniques to study bone quality, and focuses on how standard imaging techniques should be used to diagnose prevalent osteoporotic fractures.

Influence of estrogen deficiency and tibolone therapy on trabecular and cortical bone evaluated by computed radiography system in rats

PURPOSE: To verify the effects of tibolone administration on trabecular and cortical bone of ovariectomized female rats by computed radiography system (CRS). METHODS: The experiment was performed on two groups of rats previously ovariectomized, one received tibolone (OVX+T) while the other did not (OVX), those groups were compared to a control group (C) not ovariectomized. Tibolone administration (1mg/day) began thirty days after the ovariectomy and the treatment remained for five months. At last, the animals were euthanized and femurs and tibias collected. Computed radiographies of the bones were obtained and the digital images were used to determine the bone optical density and cortical thickness on every group. All results were statistically evaluated with significance set at P<0.05%. RESULTS: Tibolone administration was shown to be beneficial only in the densitometric analysis of the femoral head, performing higher optical density compared to OVX. No difference was found in cortical bone thickness. CONCLUSION: Ovariectomy caused bone loss in the analyzed regions and tibolone administered in high doses over a long period showed not to be fully beneficial, but preserved bone mass in the femoral head.

Integrated imaging approach to osteoporosis: state-of-the-art review and update

Osteoporosis is the most common of all metabolic bone disorders. It is characterized by low bone mass and microarchitectural deterioration of bone tissue, with a consequent increase in bone fragility and susceptibility to fractures. Because of the increasing aging of the world population, the number of persons affected by osteoporosis is also increasing. Complications related to osteoporosis can create social and economic burdens. For these reasons, the early diagnosis of osteoporosis is crucial. Conventional radiography allows qualitative and semiquantitative evaluation of osteoporosis, whereas other imaging techniques allow quantification of bone loss (eg, dual-energy x-ray absorptiometry and quantitative computed tomography [CT]), assessment for the presence of fractures (morphometry), and the study of bone properties (ultrasonography). In recent years, new imaging modalities such as micro-CT and high-resolution magnetic resonance imaging have been developed in an attempt to help diagnose osteoporosis in its early stages, thereby reducing social and economic costs and preventing patient suffering. The correct diagnosis of osteoporosis results in better management in terms of prevention and adequate pharmacologic or surgical treatment.

Diffuse idiopathic skeletal hyperostosis (DISH): relation to vertebral fractures and bone density

Radiographs and spinal bone mineral density (BMD) were evaluated from 342 elderly men regarding possible effects of diffuse idiopathic skeletal hyperostosis (DISH) on vertebral fractures and densitometry measurements. Prevalent vertebral fractures were more frequent among men with DISH compared to men with no DISH even after fracture prevalence was adjusted for BMD. Paravertebral calcifications should be considered in patients with DISH when interpreting BMD measurements because both dual X-ray absorptiometry (DXA) and quantitative CT (QCT) densitometry may not be reliable.

INTRODUCTION

The purpose of this study is to evaluate the prevalence of DISH in older men and its association with vertebral fractures and with BMD determined by DXA and QCT.

METHODS

Lateral radiographs of the spine were analyzed in a sample of 342 men aged ≥ 65 years participating in the MrOS Study concerning the presence and grade of DISH and vertebral fractures. Lumbar BMD was measured by both DXA (areal, grams per square centimeter) and QCT (volumetric, grams per cubic centimeter). The association between DISH, BMD, and presence of fractures was studied using χ ( 2 ) and t tests.

RESULTS

DISH was present in 52% (178/342) of the men. Men with DISH were older (mean, 75.1 vs 73.3, p < 0.05) and more likely to have prevalent fractures (28% vs 20%, p < p = 0.09). BMD assessed with DXA (1.08 vs 1.00 g/cm(2), p ≤ 0.0001), but not with QCT (0.11 vs 0.11 g/cm3, p = 0.65), was significantly higher in men with DISH compared to men without DISH. Significantly lower BMD of men with both DISH and fractures compared to men with DISH but without fractures was only detected by QCT (-25%, 0.09 vs 0.12, p < 0.05). Both DXA BMD and QCT BMD were significantly higher in severe lumbar DISH (+22% and +31%, p < 0.0001), respectively.

CONCLUSION

DISH was associated with a higher prevalence of vertebral fractures in elderly men. Lumbar ossifications related to DISH should be considered when interpreting BMD measurements to predict their fracture risk.

New imaging modalities in bone

The digital era has witnessed an exponential growth in bone imaging as new modalities and analytic techniques improve the potential for noninvasive study of bone anatomy, physiology, and pathophysiology. Bone imaging very much lends itself to input across medical and engineering disciplines. It is in part a reflection of this multidisciplinary input that developments in the field of bone imaging over the past 30 years have in some respects outshone those in many other fields of medicine. These developments have resulted in much deeper knowledge of bone macrostructure and microstructure in osteoporosis and a much better understanding of the subtle changes that occur with age, concurrent disease, and treatment. This new knowledge is already being translated into improved day-to day clinical care with better recognition, treatment, and monitoring of the osteoporotic process. As "the more you know, the more you know you don't know" certainly holds true with osteoporosis and bone disease, there is little doubt that further advances in bone imaging and analytical techniques will continue to hold center stage in osteoporosis and related research.

Vulnerability of healthy vertebrae in patients with and without previous vertebral fracture

Vertebral deformities are associated with a marked increase in morbidity, mortality, and burden in terms of sanitary expenditures. Patients with vertebral fractures have a negative impact in their health, less quality of life, and loss of functional capacity and independence. The purpose of this study was to explore the vulnerability of healthy vertebrae in patients who have sustained already a compression fracture and in patients who do not have prevalent fractures in the thoracic spine; and to explore the association of the deformity in healthy vertebrae with different variables, such as bone mineral density (BMD), body mass index, age, loss of height, presence of clinical kyphosis, history of other osteoporotic fractures, and falls occurring during the last year. Clinical data and complementary studies from 175 postmenopausal outpatients were analyzed. These women (age: 69.7±11.1 years) had not received any treatment for osteoporosis. Anteroposterior and lateral radiographs of the thoracic spine and bone densitometry of the hip were obtained; morphometry was performed in 1575 thoracic vertebrae from T4 to T12. The angle of wedging of each vertebral body was calculated using a trigonometric formula. Then, the sum of wedge angles of vertebral bodies (SWA) was determined, and Cobb angle was measured. In patients with vertebral fractures, after excluding the angles of fractured vertebral bodies, the mean wedge angle of the remaining vertebrae (MWAhealthy) was calculated. The same procedure was followed in patients without vertebral fractures. MWAhealthy was considered as an indicator of the structural vulnerability of non-fractured vertebrae. Patients with prevalent fractures had lower BMD, wider Cobb angle, and higher sum of wedge angles than patients without vertebral fractures. The proportion of patients with accentuation of clinical kyphosis was higher in the group with prevalent vertebral fractures. A highly significant difference was found in the MWAhealthy, which was higher in patients with prevalent fractures (4.1±1.3° vs. 3.0±1.1°; p<0.001). Patients showing vertebral fractures had 7.1±4.2 cm height loss in average, significantly superior than that found among non-fractured women (3.6±3.2 cm; p<0.01). In multivariate analysis, the increase of MWAhealthy was associated with advancing age (p<0.02), lower femoral neck BMD (p<0.005), presence of clinical kyphosis (p<0.01) and vertebral fractures (p<0.02). This study presents evidence that a series of factors independently influence the increase in wedging deformity of vertebral bodies that are not fractured yet. These factors could contribute to an increased vulnerability of the vertebrae, making them more susceptible to fracture.

The Founder's Lecture 2009: advances in imaging of osteoporosis and osteoarthritis

The objective of this review article is to provide an update on new developments in imaging of osteoporosis and osteoarthritis over the past three decades. A literature review is presented that summarizes the highlights in the development of bone mineral density measurements, bone structure imaging, and vertebral fracture assessment in osteoporosis as well as MR-based semiquantitative assessment of osteoarthritis and quantitative cartilage matrix imaging. This review focuses on techniques that have impacted patient management and therapeutic decision making or that potentially will affect patient care in the near future. Results of pertinent studies are presented and used for illustration. In summary, novel developments have significantly impacted imaging of osteoporosis and osteoarthritis over the past three decades.

Underreported vertebral fractures in an Italian population: comparison of plain radiographs vs quantitative measurements

PURPOSE

Vertebral fractures (VFs) are the hallmark of osteoporosis and are responsible for almost 70,000 hospital admissions yearly, implying social costs and impaired quality of life for patients. In recent years, several techniques, both qualitative and quantitative, have been proposed for VF diagnosis, but a gold standard is not yet available and the visual semiquantitative (VSQ) assessment proposed by Genant remains the most validated. However, given the lack of a standardised method, in clinical practice, the diagnosis of VF is often missed, and patients are not correctly assessed. The aim of our study was to estimate the percentage of VFs not detected in clinical practice in italian population using the VSQ method and a new morphometric technique.

MATERIALS AND METHODS

In 283 postmenopausal women referred to our clinic for osteoporosis screening, we performed a clinical examination, plain spinal radiographs (for VSQ assessment) and digital computerised morphometry (DCM) to assess VFs. Bone density was measured using dual-energy X-ray absorptiometry (DXA).

RESULTS

Forty-seven percent of patients had a T score <-2.5 standard deviations (SD), and 35.2% were osteopenic, but no significant correlations between T score and grade or number of fractures were found. DCM identified VFs in 38.5% of patients versus 32.5% using the VSQ method. Overall, 280 VFs were detected by DCM and 236 by VSQ, whereas only 105 were recognised by the reports.

CONCLUSIONS

VFs went undetected in 55.5% according to the VSQ method on standard spinal radiographs. Therefore, the morphometric technique may be helpful when performed with the semiquantitative approach to improve recognition of VFs. However, other studies are needed to further validate the utility of this new morphometric technique in clinical practice.

Incidence of new fractures in women with osteoporosis-induced vertebral fractures detected on routine lateral chest radiographs

PURPOSE

Vertebral fractures represent one of the major complications of osteopororis. Diagnosis is followed by a pharmacological, interventional or surgical treatment. Up to day there are non practice guidelines for a screening evaluation of bone fractures in elderly and most of the fractures remain undiagnosed. We prospectively evaluated the prevalence of vertebral fractures on chest X-rays to determine the diagnostic and prognostic roles of chest X-ray in predicting new bone fractures 2 years after the initial radiogram.

MATERIALS AND METHODS

Between March 2004 and October 2005, 4,045 women underwent chest X-ray in our radiology department for any indication. We identified 166 women with the presence of at least one vertebral fracture. A questionnaire was administered to these women to collect information about diagnosis of osteoporosis, history of malignancy, systemic diseases, osteoporosis-inducing drugs and pharmacological, radiological or surgical treatment received.

RESULTS

Out of the 166 women (age 73+/-10.5 years) with vertebral fractures, we interviewed 101 women; 13 had died and 52 were not found. Most of the patients were on menopause (97.1%, 98/101) with an average age of menopause of 48,2 years (+/-6 years). Among the patients on menopause, 15,8% (16/101) had undergone hysterectomy. All patients received a diagnosis of osteoporosis, which was reached with a chest X-ray report in 23.7% (24/101) of cases. A new skeletal fracture occurred in 20.5% (5/27) of patients receiving treatment against a frequency of 20.8% (16/74) in patients without treatment. No statistical difference was found between the groups (p = 0.374).

CONCLUSIONS

Inadequate treatment may explain the lack of a substantial difference in new fracture risk between treated and untreated patients. For these reason we discuss about the evaluation of an adeguate therapeutic approaches in prevention of osteoporosis-induced fractures.

Under-reporting of osteoporotic vertebral fractures on computed tomography

PURPOSE

Osteoporotic vertebral fractures are frequently asymptomatic. They are often not diagnosed clinically or radiologically. Despite this, prevalent osteoporotic vertebral fractures predict future osteoporotic fractures and are associated with increased mortality and morbidity. Appropriate management of osteoporosis can reduce future fracture risk. Fractures on lateral chest radiographs taken for other conditions are frequently overlooked by radiologists. Our aim was to assess the value of computed tomography (CT) in the diagnosis of vertebral fracture and identify the frequency with which significant fractures are missed.

MATERIALS AND METHODS

The thoracic CT scans of 100 consecutive male and 100 consecutive female patients over 55 years were reviewed. CT images were acquired on General Electric Lightspeed multi-detector (MD) CT scanners (16 or 32 row) using 1.25mm slice thickness. Midline sagittal images were reconstructed from the 3D volume images. The presence of moderate (25-40% height loss) or severe (>40% height loss) vertebral fractures between T1 and L1 was determined using an established semi-quantitative method and confirmed by morphological measurement. Results were compared with the formal CT report.

RESULTS

Scans of 192 patients were analysed (95 female; 97 male); mean age 70.1 years. Thirty-eight (19.8%) patients had one or more moderate to severe vertebral fractures. Only 5 (13%) were correctly reported as having osteoporotic fractures in the official report. The sensitivity of axial CT images to vertebral fracture was 0.35.

CONCLUSION

Incidental osteoporotic vertebral fractures are under-reported on CT. The sensitivity of axial images in detecting these fractures is poor. Sagittal reformations are strongly recommended to improve the detection rate.

Imaging of metabolic bone diseases

Osteoporosis is a serious public health problem. The incidence of osteoporotic fractures increases with age. As life expectancy increases, social costs associated with osteoporotic fractures will multiply exponentially. The early diagnosis of osteoporosis, thanks to evermore precise devices, becomes, therefore, fundamental to prevent complications of disease and unnecessary suffering.

Can abdominal multi-detector CT diagnose spinal osteoporosis?

The aim of this study was to (1) generate quantitative CT (QCT) densitometric data based on routine abdominal multi-detector (MDCT) examinations and (2) investigate whether these data can be used to differentiate osteoporotic from healthy females. Twenty-five female patients (group A) with a history of radiotherapy were examined both with routine abdominal MDCT and standard QCT to generate a MDCT-to-QCT conversion equation. Twenty-one osteoporotic (group B) and 23 healthy female patients (group C) were also recruited in the study. Patients of groups B and C underwent routine abdominal MDCT examination for various clinical indications. Mean bone mineral density (BMD) in patients of group A was 103.4 mg/ml +/- 32.8 with routine abdominal MDCT and 91.0 mg/ml +/- 28.5 with QCT. Quantitative CT BMD(QCT) values for patients in groups B and C were calculated utilizing the BMD(MDCT) values derived from routine abdominal MDCT data sets and the MDCT to QCT conversion equation: BMD(QCT)=0:78 x BMD(MDCT) + 10:13. The calculated QCT densitometric data adequately differentiated osteoporotic from healthy females (area under ROC curve 0.828, p = 0.05). In conclusion, this study showed that in a group of female patients, QCT data derived from routine abdominal MDCT examinations discriminated osteoporotic from healthy subjects.

Significance of sagittal reformations in routine thoracic and abdominal multislice CT studies for detecting osteoporotic fractures and other spine abnormalities

The purpose was to assess osteoporotic vertebral fractures and other spinal lesions in sagittal reformations obtained from routine multidetector computed tomography (MDCT) studies of the thorax and abdomen, to compare sagittal reformations with axial images in detecting these lesions and to investigate how frequently they were missed in the official radiology report. Routine abdominal or thoracoabdominal MDCT using a standard protocol was performed in 112 postmenopausal women. Axial images and sagittal reformations were analyzed separately by two radiologists in consensus and were compared in order to evaluate how often spinal lesions could be detected. In addition the official radiology reports were assessed to determine how many of those abnormalities were identified. Spine abnormalities were visualized in 101/112 postmenopausal women. In 27 patients osteoporotic vertebral deformities were found; 6 of these were shown in the axial images, but none of these were diagnosed in the official radiology report. Additional abnormalities included degenerative disc disease, osteoarthritis of the facet joints, scoliosis, hemangiomas and bone metastases. In only 9/101 patients spine abnormalities were mentioned in the radiology report. Sagittal reformations of standard MDCT images provide important additional information on spinal abnormalities; in particular, osteoporotic vertebral deformities are substantially better detected.