Orthopaedic Session I
AB094. SOH24AB_170. A meta-analysis of the diagnostic accuracy of Hounsfield units on computed tomography relative to dual-energy X-ray absorptiometry for the diagnosis of osteoporosis in the spine surgery population
Kielan Wilson1, Jake McDonnell2, Mathieu Riffault3, Scott Wagner4, Alexander Vaccaro5, David Hoey3, Joseph Simon Butler2
1School of Medicine, University College Dublin, Belfield, Dublin, Ireland;
2National Spinal Injuries Unit, Mater Misericordiae University Hospital, Dublin, Ireland;
3Centre for Bioengineering, Trinity College, Dublin, Ireland;
4Department of Orthopaedics, Walter Reed Medical Center, Bethesda, Maryland, USA;
5Department of Orthopaedics, Rothman Institute, Thomas Jefferson University Hospital, Philadelphia, USA
Background: Preoperative identification of osteoporosis (OP) in spine surgery patients is of crucial importance. Limitations, such as access and reliability, are associated with dual-energy X-ray absorptiometry (DXA). The Hounsfield unit (HU), a readily available measure on computed tomography (CT), is a potential diagnostic tool for reduced bone mineral density (BMD). However, the optimal threshold settings for diagnosing OP are undetermined.
Methods: Selected studies included comparison of HU (index test) with DXA (reference test). Data quality was assessed using Quality Assessment of Diagnostic Accuracy Studies (QUADAS)-2 criteria. Studies were characterised based on the threshold of the index test used, with the goal of obtaining a high sensitivity, high specificity or balanced sensitivity-specificity test.
Results: Nine studies were included. In the high specificity group, pooled sensitivity was 0.652 [95% confidence interval (CI): 0.526–0.760], specificity was 0.795 (95% CI: 0.711–0.859) and diagnostic odds ratio was 6.652 (95% CI: 4.367–10.133). In the high sensitivity group, overall pooled sensitivity was 0.912 (95% CI: 0.718–0.977), specificity was 0.67 (95% CI: 0.57–0.75) and diagnostic odds ratio was 19.424 (95% CI: 5.446–69.275). In the balanced sensitivity-specificity group, overall pooled sensitivity was 0.625 (95% CI: 0.504–0.732), specificity was 0.914 (95% CI: 0.823–0.960) and diagnostic odds ratio was 14.880 (95% CI: 7.521–29.440). Considerable heterogeneity existed throughout.
Conclusions: HU is a clinically useful tool to diagnose OP. However, the heterogeneity in this study warrants caution in the interpretation of results. Differing HU threshold values impact the diagnostic ability of this test. We would propose a threshold of 150 HU to differentiate between normal and low BMD, and a value of 110 HU to indicate OP.
Keywords: Computed tomography (CT); dual-energy X-ray absorptiometry (DXA); Hounsfield units (HU); osteoporosis (OP); spine surgery
Acknowledgments
Funding: None.
Conflicts of Interest: The authors have no conflicts of interest to declare.
Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.
Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See: https://creativecommons.org/licenses/by-nc-nd/4.0/.
doi: 10.21037/map-24-ab094
Cite this abstract as: Wilson K, McDonnell J, Riffault M, Wagner S, Vaccaro A, Hoey D, Butler JS. AB094. SOH24AB_170. A meta-analysis of the diagnostic accuracy of Hounsfield units on computed tomography relative to dual-energy X-ray absorptiometry for the diagnosis of osteoporosis in the spine surgery population. Mesentery Peritoneum 2024;8:AB094.
