Vertebral deformity is the classical hallmark of osteoporosis. Three types of vertebral deformity are usually described: crush, wedge and biconcave deformities. However, there are few data concerning the descriptive epidemiology of the individual deformity types, and differences in their underlying pathogenesis and clinical impact remain uncertain. The aim of this study was to compare the epidemiological characteristics of the three types of vertebral deformity and to explore the relationships of the number and type of deformity with back pain and height loss. Age-stratified random samples of men and women aged 50 years and over were recruited from population registers in 30 European centers (EVOS study). Subjects were invited to attend for an interviewer-administered questionnaire and lateral spinal radiographs. The presence, type and number of vertebral deformities was determined using the McCloskey-Kanis algorithm. A total of 13,562 men and women were studied; mean age in men was 64.4 years (SD 8.5), and in women 63.8 years (SD 8.5 years). There was evidence of variation in the occurrence of wedge, crush and biconcave deformity by age, sex and vertebral level. Wedge deformities were the most frequent deformity and tended to cluster at the mid-thoracic and thoraco-lumbar regions of the spine in both men and women. Similar predilection for these sites was observed for crush and to a lesser extent biconcave deformities though this was much less marked than for wedge deformities. In both sexes the frequency of biconcave deformities was higher in the lumbar than the thoracic spine and unlike the other deformity types it did not decline in frequency at lower lumbar vertebral levels. The prevalence of all three types of vertebral deformity increased with age and was more marked in women. There were no important differences in the effect of age on the different deformity types. All types of deformity were associated with height loss, which was greatest for individuals with crush deformity. Back pain was also associated with all types of deformity. Overall, these results do not suggest important differences in pathophysiology between the three deformity types. Biomechanical factors appear to be important in determining their distribution within the spine. All deformity types are linked with adverse outcomes, though crush deformities showed greater height loss than the other deformity types.
Vertebral height ratios are used to define vertebral deformity in clinical and epidemiologic studies of vertebral osteoporosis. However, few data have been obtained on the variation in these ratios in different populations using standard methods. We examined vertebral morphometric measurements obtained in a population survey from three centers: Malmö (Sweden), Montceau-les-Mines (France), and Graz (Austria), to study the influence of sex and the population center on vertebral height ratios. Radiographs were obtained according to a standardized protocol, and morphometric measurements, anterior height Ha, central height Hc, and posterior height Hp, made in Berlin. The height ratios anterior, Ha/Hp, central, Hc/Hp, posterior I, Hp/Hp', and posterior II, Hp/Hp" (Hp' = posterior height of vertebrae above, Hp" = posterior height of vertebrae below) were calculated for each vertebra from T4 to L4. The mean and standard deviation of these ratios for each sex and each center were derived using a statistical trimming procedure to normalize the distribution. Threshold values for defining grade 1 and grade 2 deformities, wedge, biconcavity, and compression, were calculated using these parameters. Anterior and central vertebral height ratios were smaller in males than females (p < 0.01). There were significant differences between the three centers (p < 0.01) both in the trimmed mean values for anterior and central vertebral height ratios and in the thresholds derived using standard criteria for defining wedge and biconcavity deformity. The data confirm the impression from single-center studies that vertebral height ratios vary between populations and suggest that reference values for vertebral height ratios should be derived separately for males and females within individual populations whenever possible.
Several algorithms are currently in use for evaluating vertebral deformities from plain lateral radiographs of the lumbar and thoracic spine. However, the effects of measurement imprecision as well as uncertainties over image magnification on the correct identification of prevalent and incident vertebral deformities with these algorithms has been little studied. In a pilot study for the European Prospective Osteoporosis Study (EPOS), plain radiographs were submitted to a single central evaluating centre for measurement of vertebral height from T4 to L4. The thoracic and lumbar spines were imaged on separate films, and we have assessed the precision of measurement of vertebral heights and height ratios. The standard deviation of the differences between films of each of three height measurements ranged from 1.1 to 1.2 mm. A two-stage strategy for identifying incident deformities was devised. This required that the vertebra be a prevalent deformity at the time of the second radiograph and also that at least one of the vertebral ratios should have changed significantly since the first radiograph. The second stage removed all but two of the 18 vertebrae flagged positive in the first stage but not considered to be certain incident fractures by clinical reading of the radiographs.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.