The association between bone density evaluated on CT or MRI versus the gold standard dual-energy X-ray absorptiometry (DEXA) in the lumbar spine and hip: a meta-analysis
Jul 2026· Brain and Spine· Vol 6, pp. 106246· 0 citations· 76 references
Medicine
TL;DR
When CT is available, HU appears to be the better-supported opportunistic marker for low BMD than VBQ, and AUC-based diagnostic discrimination of HU was consistent across vertebrae, with slightly better results at L2 and the mean of L1–L4.
Abstract
Introduction CT-based Hounsfield units (HU) and MRI-based vertebral bone quality (VBQ)-scores are opportunistic markers of bone mineral density and potential alternatives for dual-energy X-ray absorptiometry (DEXA). Research question What is the correlation between HU values and VBQ-scores in relation to DEXA, and what is the corresponding area-under-the-curve (AUC)-based diagnostic discrimination to detect osteopenia and osteoporosis? Material and methods PubMed, Embase, Web of Science, Cochrane Library, and CINAHL were searched through August 2025 for studies reporting correlations between DEXA and CT and/or MRI or the AUC-based diagnostic discrimination of CT and/or MRI to detect osteopenia and osteoporosis. Random effects models were used to calculate pooled correlation coefficients and AUC values along with 95% confidence intervals. Results Forty-three studies, including 8222 patients, were analyzed. HU demonstrated stronger correlations with DEXA T-scores than the VBQ-score (maximum correlation coefficient: 0.741 (95% CI: 0.578-0.847) vs. −0.476 (95% CI: −0.548 to −0.398) and greater AUC-based diagnostic discrimination for osteopenia and osteoporosis (maximum AUC: 0.875 (95% CI: 0.841-0.909) vs. 0.806 (95% CI: 0.684-0.929) across all vertebrae and DEXA sites. Correlation and AUC-based diagnostic discrimination of HU were consistent across vertebrae, with slightly better results at L2 and the mean of L1–L4. VBQ-score correlations were highest at L1 and gradually decreased from L1 to L4. Discussion and conclusion When CT is available, HU appears to be the better-supported opportunistic marker for low BMD than VBQ. All vertebrae demonstrated comparable correlation and AUC-based diagnostic discrimination, with L2 HU and the mean of L1-L4 HU showing slightly superior results.
Both HU and VBQ offer useful assessments of vertebral bone quality, but HU provides higher and more stable diagnostic accuracy, demonstrating higher sensitivity, specificity, and accuracy for detecting osteopenia and osteoporosis.
Omar Lubbad, Akram Hagos, Laila Lubbad et al.· European Radiology· 0 citations
In patients undergoing cervical spine surgery, C-VBQ demonstrates consistent associations with C-HU and DXA T-scores, supporting its potential for opportunistic preoperative bone quality assessment and Integrating radiological indicators such as C-VBQ and C-HU with DXA and BTMs may enable a more comprehensive, but still cautiously interpreted, perioperative bone health evaluation.
Xiaoteng Feng, Xiujia Xia, Zelin Shen et al.· European spine journal· 0 citations
VBQ can serve as an opportunistic exploratory screening marker of low BMD and FBQcsf may complement VBQ by identifying early marrow-related changes, although further validation is required.
Margrit Elis Müller, João Paulo Colhado Ferreira, Laura Mulazzani Minuzzi Macedo et al.· Skeletal Radiology· 0 citations
The study aimed to explore an accessible quantification of bone mineral density (BMD) through Radiographic Bone Aluminium Equivalence (RBAE) as determined by Digital Radiography (DR), compared to dual-energy X-ray absorptiometry (DEXA) and computed tomography (CT) in ex vivo animal model. Metacarpal and metatarsal bones (n = 24) from skeletally mature sheep were imaged using standard DR, DEXA, and CT protocols. DR-derived BMD values were calculated from calibrated greyscale intensities using an aluminum step-wedge and image-analysis workflow. Correlation and regression analyses were performed to evaluate the relationship between the different modalities, whereas the intraclass correlation coefficient (ICC) and Bland–Altman analyses were used to assess agreement between the measurement methods. DR-derived BMD as expressed as BRAE demonstrated strong linear correlation with DEXA (r = 0.779, p = 0.001) and moderate linear correlation with CT (r = 0.536, p = 0.04). Across all imaging modalities, metatarsal bones exhibited significantly higher BMD than metacarpal bones, with clear bilateral symmetry observed within each bone type. The consistency of results across modalities strengthens the validity of the findings and supports the reliability of each technique for detecting biologically meaningful differences in BMD. The agreement between DEXA, CT and digital radiography underscores the feasibility of using radiographic BMD to quantify BMD. Digital radiography, supported by standardized calibration and analysis, yields a reproducible BMD estimates that align closely with DEXA and CT measurements. These findings highlight DR as a cost-effective and accessible option for BMD assessment, while providing valuable baseline insight into normal mineral distribution. This information supports future research on pathological bone loss, imaging validation, and therapeutic strategies to improve bone quality.
M. M. Kamal, Ahmed I. Abdelgalil, E. Hassan· BMC Medical Imaging· 0 citations
OBJECTIVE
This study compared Hounsfield unit (HU) measurements obtained from different regions of interest (ROIs) on lumbar CT for assessing bone mineral density (BMD) and discriminating osteoporosis and thoracolumbar fragility fracture status, aiming to evaluate whether ROI selection meaningfully influences HU-based assessment.
METHODS
Five HU measurement methods were evaluated using lumbar CT. Their correlations with dual-energy X-ray absorptiometry (DEXA)-derived BMD and their discriminative performance for osteoporosis and thoracolumbar fragility fracture status were analyzed. Receiver operating characteristic (ROC) curves were constructed, and pairwise comparisons of areas under the curve (AUCs) were performed using the DeLong test. A sensitivity analysis was additionally conducted after excluding substituted vertebral levels and recalculating mean lumbar HU using only non-substituted vertebrae.
RESULTS
All five HU measurement methods showed significant correlations with DEXA-derived BMD, and no statistically significant differences in discriminative performance were observed among the five ROI methods in the primary analysis. In the sensitivity analysis excluding substituted vertebral levels, the AUCs remained comparable across methods for osteoporosis (0.816-0.826) and thoracolumbar fragility fracture status (0.677-0.689), with all pairwise DeLong tests showing no statistically significant differences (all p > 0.05).
CONCLUSION
Different lumbar CT ROI methods demonstrated comparable performance in assessing BMD and discriminating thoracolumbar fragility fracture status, and sensitivity analysis confirmed that exclusion of substituted vertebral levels did not materially affect the results. No ROI method showed statistically significant superiority, suggesting that ROI selection may be guided by clinical feasibility and workflow convenience rather than by diagnostic performance alone.
ADVANCES IN KNOWLEDGE
This study compares five commonly used lumbar CT HU measurement methods and shows that their performance is broadly similar. The findings suggest that ROI selection may be guided primarily by clinical feasibility and workflow convenience, although further external validation is required before routine clinical application.
Osteoporosis screening is essential for early intervention and fracture prevention. While dual-energy X-ray absorptiometry (DXA) remains the gold standard for bone mineral density (BMD) assessment, alternative, cost-effective methods are being explored. Radiogrammetry (DXR) has shown promising results; however, it needs specialized computer software. Hand radiographs, particularly the second metacarpal cortical index (2MCI), have shown promise in BMD evaluation. This study aims to systematically review the evidence on the diagnostic accuracy of the 2nd MCI in assessing BMD. A systematic search of PubMed, Scopus, and EMBASE databases was conducted on May 6, 2025, to identify observational and diagnostic accuracy studies evaluating the relationship between the 2MCI and BMD in adults aged 50 years and older. Case reports and non-English studies were excluded. Data extraction followed PRISMA guidelines, and study quality was assessed using QUADAS-2. Due to heterogeneity in study designs, a narrative synthesis was performed. Six studies with a total of 1028 participants were included. Findings consistently demonstrated that 2MCI radiographs correlate with BMD. In addition, machine learning models enhanced the predictive performance of the 2MCI. However, accuracy of findings particularly sensitivity and specificity remains variable in identifying osteopenia or osteoporosis. This study highlights the importance of adhering to standardized protocols and continuously refining measurement approaches to enhance reliability of 2MCI as screening tool for either osteopenia or osteoporosis. With improved study designs, it further strengthens the clinical applicability of these findings.
Elson Kow, Wiria Aryanta· The Egyptian Journal of Radi...· 0 citations
