The Accuracy of Surgeons’ Intuitive Diagnosis of Osteoporosis Using Radiographs and Computed Tomography Images of the Lumbar Spine

Study Design: Observational cross-sectional study. Objective: To evaluate the diagnostic accuracy of orthopedic surgeons’ intuitive assessment of low bone mineral density (BMD) using lumbar spine radiographs and sagittal CT images, and to assess the influence of clinical experience and brief diagnostic training. Summary of Background Data: Although osteoporosis affects surgical planning and postoperative outcomes, dual X-ray absorptiometry (DXA) is not always accessible. Surgeons sometimes attempt to estimate BMD intuitively from radiographs or CT images; however, the accuracy and determinants of such assessments remain unclear. Methods: Ninety-two evaluators (42 board-certified orthopedic surgeons and 50 nonspecialists or residents) assessed 45 lumbar radiographs and 45 sagittal CT images from patients who had undergone DXA. Evaluators judged whether each image suggested “weaker-than-normal bone.” Diagnostic accuracy and discrimination index (DI) were calculated using T-score cutoffs of –2.5 and –1.0. Associations with clinical experience and frequency of imaging evaluations were analyzed, and the effects of a brief training module were evaluated. Results: Overall diagnostic accuracy was low for both imaging modalities, particularly at the –2.5 threshold (radiographs: median 53.3% [33.3–75.6]; CT: 53.3% [31.1–80.0]). Orthopedic surgeons demonstrated slightly higher accuracy than nonspecialists (radiographs: 55.6% vs . 51.1%; CT: 60.0% vs . 46.7%). Diagnostic accuracy for CT correlated with clinical experience (r = 0.408, P <0.001). After brief training, nonspecialists showed significant improvement in CT-based diagnosis ( P =0.003), whereas orthopedic surgeons showed no meaningful change. CT demonstrated higher overall accuracy than radiographs, although DI did not differ significantly. Conclusion: Surgeons’ intuitive ability to detect low BMD from single-view radiographs or CT images is limited. Although orthopedic surgeons perform slightly better than nonspecialists, the clinical significance of this difference is questionable. Training improved diagnostic performance only among nonspecialists. Formal diagnostic tools remain essential for reliable osteoporosis screening. Level of Evidence: Level III.