Opportunistic screening for the presence of vertebral fractures using L1 trabecular bone density on non-contrast chest CT

Abstract

Aims: To evaluate the effectiveness of opportunistic screening using L1 trabecular density on non-contrast chest CT for identifying the presence of vertebral fractures. Methods: This retrospective cross-sectional study included 385 adult patients (≥40 years) who underwent non-contrast chest CT. L1 trabecular attenuation was measured at the mid-vertebral level. Vertebral compression fractures were assessed. The diagnostic performance of L1 hounsfield unit (HU) and clinical variables was evaluated using regression and ROC analyses. Results: Vertebral fractures were found in 137 patients (35.6%). Mean L1 density was significantly lower in the fracture group (71.2±35.1 HU) compared to the non-fracture group (134.4±36.6 HU, p<0.001). L1 HU showed a strong inverse correlation with age (r=-0.952). ROC analysis for L1 HU yielded an AUC of 0.882. An optimal threshold of 94 HU demonstrated 86.9% sensitivity and 89.1% specificity. Conclusion: L1 trabecular attenuation on routine non-contrast chest CT serves as a useful opportunistic screening tool associated with the presence of vertebral fractures.