Identifying vertebral fractures in the Japanese population using the trabecular bone score: a cross-sectional study

Background The trabecular bone score (TBS) is reported to be an independent predictor of fracture risk in patients with primary or secondary osteoporosis. However, there have been few reports on its use in the Japanese population. This study aimed to investigate the risk factors for vertebral fracture in the Japanese population and to evaluate the usefulness of TBS. Methods This cross-sectional study involved 279 patients aged 60–90 years in whom bone mineral density (BMD) was measured by dual-energy X-ray absorptiometry (DXA). TBS was calculated based on the DXA scans. The presence or absence of vertebral fractures was assessed from T11 to L5. The patients were divided into those with vertebral fractures (VF group, n = 104) and those without vertebral fractures (non-VF group, n = 175). Results Of the 104 patients in the VF group, 75 had 1 vertebral fracture and 29 had 2 or more fractures. The mean TBS was 1.28 in the VF group and 1.35 in the non-VF group ( p < 0.001). The mean BMD values at the lumbar spine and femoral neck were lower in the VF group ( p < 0.001). The areas under the receiver-operating characteristic curve for incidence of vertebral fractures were 0.700, 0.737, and 0.689 for TBS, lumbar spine BMD, and femoral neck BMD, respectively. Multiple logistic regression analysis identified lumbar spine BMD, TBS, and female sex as significant risk factors for vertebral fractures. The proportion of patients in the group with osteoporosis or osteopenia who had vertebral fractures was higher in those with a low TBS (≤ 1.23) than in those with a non-low TBS (> 1.23). Conclusion TBS was a significant indicator of vertebral fractures in the Japanese population and might contribute to identifying patients with vertebral fractures, particularly those with osteopenia who need pharmacologic therapy.