JOURNAL OF BONE AND MINERAL RESEARCH zyxwvuts Volume zyxwvutsrqponm 8, Number zyxwvutsrqp 9, 1993 Mary Ann Lkberl, lac., Publishers zyxwvutsrqp Vertebral Fracture Assessment Using a Semiquantitative Technique HARRY K. GENANT,I CHUN Y. WU,' CORNELIS VAN KUIJK,' arid MICHAEL C. NEVITT' ABSTRACT The assessment of vertebral fracture b j conventional radiography has been refined and improved using either semiquantitative or quantitative criteria. The inter- and intraobserver variability was determined for a semiquantitative visual approach that we routinely use in clinical studies for assessing prevalent and incident vertebral fractures. In addition, the semiquantitative approach was compared with a quantitative morpho- metric approach. The incidence and prevalence of vertebral fractures were determined in 57 postmenopausal women (age 65-75 years) by three independent observers. The radiographic basis for fracture definitions and the source of interpretative errors are illustrated. The results show excellent intraobserver agreement and good interobserver agreement for the semiquantitative technique. We conclude that the semiquantitative ap- proach can be applied reliably in vertebral fracture assessment when performed using well-defined criteria. INTRODUCTION HE ASSESSMENT OF VERTEBRAL FRACTURE on conven- T tional radiographs has been refined by using either semiquantitative or quantitative criteria. Semiquantitative visual approaches based on grading of vertebral fractures have been Furthermore, various quantitative techniques based on measurements of the vertebral body dimensions have been developed in the last few year~.(~-'O) This considerable interest in vertebral fracture assessment is linked to the increased interest in osteoporosis research. Osteoporosis is a condition of diminishing bone content and increasing damage to the bone architecturi:, eventually leading to bone fracture. Vertebral fractures :ire the most common osteoporotic fractures(l') and are therefore used zyxwvu as outcome variables in osteoporosis preventicn and treat- ment studies.(la) Limited data are available that show the comparative value of the different approaches for vertebral fracture as- sessment.(13-L51 In this paper, we present a comparison of a semiquantitative approach(a)that is used routinely by us and others in clinical and a quantitative ap proach previously described.'") We assess the inter- and intraobserver reproducibility of the semiquantitative ap- proach. We also illustrate radiographically the basis of fracture definitions and the source of interpretative errors. MATERIALS AND METHODS Study population The baseline and follow-up (after 2 years) lateral radio- graphs of the thoracic and lumbar spine were evaluated for 57 postmenopausal women (age 65-75 years) selected from a subset of a large population of women participating in the study of osteoporotic fractures."" The study popula- tion was enriched in terms of both prevalent and incident fractures, and patients with unreadable films were ex- cluded. All films were taken at a focus-film distancee of 40 inches. The x-ray beam was centered over T8 for the tho- racic spine and over L3 for the lumbar spine. Semiquantitative approach A visual semiquantitative grading of vertebral fractures was done by two independent observers, one who was con- sidered experienced and the other inexperienced but 'Department of Radiology, University of California, San Francisco. 'Department of Epidemiology and Biostatistics. [Jniversity of California, San Francisco. 1137