The identification of vertebral fracture in osteoporosis is based mainly on the identification of abnormal variation in vertebral shape, but this can be misleading in the presence of a non-fracture deformity or normal variant of vertebral shape. Qualitative identification of vertebral fracture (Qual) is influenced by the subjectivity of the approach, and although more objective, the semiquantitative method (SQ) can be difficult to apply. In addition, there has been little independent evaluation of SQ in relation to other approaches. We aimed to evaluate a new algorithm-based approach for the qualitative identification of vertebral fracture (ABQ) and to compare it with SQ and Qual. Two radiologists reported spinal radiographs for 372 postmenopausal women using Qual (reader 1), and SQ and ABQ (reader 2). Non-fracture deformities and normal variants were also reported using Qual and ABQ. The prevalence of vertebral fracture by subjects was higher for SQ (24%) than for Qual (11%) and ABQ (7%). Agreement was poor between SQ and the other methods, and moderate between Qual and ABQ. Twenty-two women with vertebral fracture were agreed by all three methods, similar to the total identified by ABQ (25 women). Seventeen women diagnosed with fracture by Qual, had non-fracture deformity or normal variant (but no fracture) according to ABQ. Of the women with SQ fractures, 53% and 70% were identified negative for fracture but positive for non-fracture deformity or normal variant by ABQ and Qual. The main sources of discrepancy between SQ and the other methods were Scheuermann's disease, normal variation, and degenerative change accompanied by short anterior vertebral height. For all methods, bone mineral density (BMD) and BMD Z-scores were lower in women with vertebral fractures than in those with no fractures. Bone mineral density and BMD Z-scores were also lower at the lumbar spine and total body in women with vertebral fractures according to Qual and ABQ than they were for SQ, and were lower in women with SQ fractures agreed by Qual and ABQ, compared with those diagnosed negative for fracture by Qual and ABQ (p<0.01). We conclude that poor agreement between methods arises mainly from difficulties in differentiating true fracture from non-fracture deformity. Our new approach attempts to address this problem but requires further testing in a larger study population.

Osteoporotic vertebral fracture is associated with increased morbidity and mortality. As a powerful predictor of future fracture risk, the identification of vertebral fracture helps target individuals who will benefit from anti-fracture therapy. The identification of vertebral fractures is problematic because (1) "normal" radiological appearances in the spine vary greatly both among and within individuals; (2) "normal" vertebrae may exhibit misleading radiological appearances due to radiographic projection error; and (3) "abnormal" appearances due to non-fracture deformities and normal variants are common, but can be difficult to differentiate from true vertebral fracture. Various methods of vertebral fracture definition have been proposed, but there is no agreed gold standard. Quantitative methods of vertebral fracture definition are objective and reproducible, but the major limitation of these methods is their inability to differentiate between vertebral deformity and vertebral fracture. The qualitative visual approach draws on the expertise of the reader, but it is a subjective method with poor interobserver agreement. Semiquantitative assessment of vertebral fracture is a standardized visual method, which is commonly applied in research studies as a surrogate gold standard. This method is more objective and reproducible than a purely qualitative approach, but can be difficult to apply. The established methods focus primarily on the identification of "reduced" or short vertebral height as an indication of vertebral fracture, but this is also a feature of some non-fracture deformities and normal variants. A modified visual approach known as algorithm-based qualitative assessment of vertebral fracture (ABQ) has recently been introduced, and this focuses on radiological evidence of change at the vertebral endplate as the primary indicator of fracture. Preliminary testing of the ABQ method has produced promising results, but the method requires further evaluation. Vertebral imaging by means of dual energy X-ray absorptiometry (DXA) scanner produces images of near-radiographic quality at a fraction of the radiation dose incurred by conventional radiography. There is growing interest in vertebral fracture assessment using this technique as a means of assessing a patient's fracture risk. Given the increasing availability of new technology and the importance of accurate diagnosis of vertebral fracture, there is an urgent need for better awareness of and training in the definition of vertebral fracture. Methods of vertebral fracture definition should be validated by testing the association with clinical outcomes of vertebral fracture, in particular the prediction of incident fractures.

Vertebral fractures are the most common type of osteoporotic fracture, but more than two-thirds remain undetected. We have examined the relationship between height loss and the development of new vertebral fractures to determine whether there is a height loss threshold that has useful clinical accuracy to detect new fractures. We studied 985 postmenopausal women with osteoporosis in the placebo arms of the Vertebral Efficacy with Risedronate Therapy studies. Height was measured annually for 3 years using a wall-mounted stadiometer. New fractures were determined using quantitative and semi-quantitative radiographic morphometry. The relationship between height loss over three years and the number of new vertebral fractures was: height loss (cm) = 0.95 x number of new vertebral fractures-0.4 cm (r = 0.33). The odds ratio for the development of a new fracture increased up to 20.6 (95% confidence interval, 9.3, 45.8) when height loss was greater than 4.0 cm. At a threshold of > 2.0 cm height loss over 3 years, sensitivity was 35.5% for detecting new vertebral fractures and specificity was 93.6%. These findings show that there is a strong relationship between the amount of height loss and the risk of a new vertebral fracture. While there is no cut-off that can reliably rule in a new fracture, height loss of < or = 2.0 cm over 1-3 years has acceptable accuracy for ruling out an incident fracture.

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Non-osteoporotic SVH may mimic VF but is excluded in ABQ. In men, this led to discordance between ABQ and other methods, but SVH was not linked to low bone density. Exclusion of SVH could reduce false positives.Introduction: Non-osteoporotic short vertebral height (SVH) may mimic vertebral fracture (VF). The aims were to (1) compare the prevalence of VF in elderly men using the algorithm-based qualitative (ABQ), semiquantitative (SQ), and triage-quantitative morphometric (triage-QM) methods; (2) identify reasons for discordance between methods; and (3) determine whether SVH identified by ABQ is linked to low BMD. Materials and Methods:We studied a subset of 732 men ages Ն65 yr participating in the Osteoporotic Fractures in Men (MrOS) Study. Criteria for VF were (1) ABQ: endplate depression; (2) SQ: estimated vertebral height reduction Ն20%; (3) triage-QM: vertebral height ratio >3 SD below the reference mean, on radiographs showing evidence of VF. Criteria for SVH (ABQ) were apparent "reduction" in vertebral height Ն ∼15%, without evidence of endplate depression. Results:The prevalence of at least one VF was 10% (ABQ); 13% (SQ) and 11% (QM-triage) and of at least one SVH (ABQ) was >50%. Agreement between methods was moderate ( ‫ס‬ 0.42-0.62). Discordance between methods related mainly to classification of mild thoracic wedging or possible traumatic VF by ABQ. Mean BMD was lower in men with VF (any diagnostic method) than in those without (two-sample t-test, p < 0.05). For ABQ, BMD was similar in men with SVH (no VF) and men with normal vertebrae (ANOVA, p > 0.05). Mean BMD was significantly lower than expected in 40 men with VF identified by all three methods and average or more than average in those identified by a single method. Conclusions: Among elderly men (1) the prevalence of VF ranges from 10% to 13%: (2) agreement between diagnostic methods is moderate: discordance relates mainly to differential classification of mild thoracic deformities or ABQ definition of VF as traumatic; and (3) SVH identified by ABQ is common and not linked to low BMD.