Daniel P Ahern1, Jake M McDonnell2, Mathieu Riffault3, Shane Evans4, Scott C Wagner5, Alexander R Vaccaro6, David A Hoey3, Joseph S Butler7. 1. School of Medicine, Trinity College Dublin, DN, Ireland; National Spinal Injuries Unit, Department of Trauma & Orthopaedic Surgery, Mater Misericordiae University Hospital, DN, Ireland; Trinity Centre for Biomedical Engineering, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin 2 D02 R590, Ireland. Electronic address: daniel.ahern@umail.ucc.ie. 2. Royal College of Surgeons in Ireland, St. Stephen's Green, DN, Ireland. 3. Trinity Centre for Biomedical Engineering, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin 2 D02 R590, Ireland; Department of Mechanical and Manufacturing Engineering, School of Engineering, Trinity College Dublin, Dublin 2 D02 DK07, Ireland; Advanced Materials and Bioengineering Research Centre, Trinity College Dublin & RCSI, Dublin 2 D02 VN51, Ireland. 4. School of Medicine and Medical Science, University College Dublin, DN, Ireland. 5. Department of Orthopaedic Surgery, Walter Reed National Military Medical Center, Bethesda, MD, USA. 6. Department of Orthopedic Surgery, Rothman Institute, Thomas Jefferson University, Philadelphia, USA. 7. National Spinal Injuries Unit, Department of Trauma & Orthopaedic Surgery, Mater Misericordiae University Hospital, DN, Ireland; School of Medicine and Medical Science, University College Dublin, DN, Ireland.
Abstract
BACKGROUND: The preoperative identification of osteoporosis in the spine surgery population is of crucial importance. Limitations associated with dual-energy x-ray absorptiometry, such as access and reliability, have prompted the search for alternative methods to diagnose osteoporosis. The Hounsfield Unit(HU), a readily available measure on computed tomography, has garnered considerable attention in recent years as a potential diagnostic tool for reduced bone mineral density. However, the optimal threshold settings for diagnosing osteoporosis have yet to be determined. METHODS: We selected studies that included comparison of the HU(index test) with dual-energy x-ray absorptiometry evaluation(reference test). Data quality was assessed using the standardised QUADAS-2 criteria. Studies were characterised into 3 categories, 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: 9 studies were eligible for meta-analysis. In the high specificity group, the pooled sensitivity was 0.652 (95% CI 0.526 - 0.760), specificity 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, the overall pooled sensitivity was 0.912 (95% CI 0.718 - 0.977), specificity was 0.67 (0.57 - 0.75) and diagnostic odds ratio was 19.424 (5.446 - 69.275). In the balanced sensitivity-specificity group, the overall pooled sensitivity was 0.625 (95% CI 0.504 - 0.732), specificity was 0.914 (0.823 - 0.960) and diagnostic odds ratio was 14.880 (7.521 - 29.440). Considerable heterogeneity existed throughout the analysis. CONCLUSION: In conclusion, the HU is a clinically useful tool to aide in the diagnosis of osteoporosis. However, the heterogeneity seen in this study warrants caution in the interpretation of results. We have demonstrated the impact of differing HU threshold values on the diagnostic ability of this test. We would propose a threshold of 135 HU to diagnose OP. Future work would investigate the optimal HU cut-off to differentiate normal from low bone mineral density.
BACKGROUND: The preoperative identification of osteoporosis in the spine surgery population is of crucial importance. Limitations associated with dual-energy x-ray absorptiometry, such as access and reliability, have prompted the search for alternative methods to diagnose osteoporosis. The Hounsfield Unit(HU), a readily available measure on computed tomography, has garnered considerable attention in recent years as a potential diagnostic tool for reduced bone mineral density. However, the optimal threshold settings for diagnosing osteoporosis have yet to be determined. METHODS: We selected studies that included comparison of the HU(index test) with dual-energy x-ray absorptiometry evaluation(reference test). Data quality was assessed using the standardised QUADAS-2 criteria. Studies were characterised into 3 categories, 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: 9 studies were eligible for meta-analysis. In the high specificity group, the pooled sensitivity was 0.652 (95% CI 0.526 - 0.760), specificity 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, the overall pooled sensitivity was 0.912 (95% CI 0.718 - 0.977), specificity was 0.67 (0.57 - 0.75) and diagnostic odds ratio was 19.424 (5.446 - 69.275). In the balanced sensitivity-specificity group, the overall pooled sensitivity was 0.625 (95% CI 0.504 - 0.732), specificity was 0.914 (0.823 - 0.960) and diagnostic odds ratio was 14.880 (7.521 - 29.440). Considerable heterogeneity existed throughout the analysis. CONCLUSION: In conclusion, the HU is a clinically useful tool to aide in the diagnosis of osteoporosis. However, the heterogeneity seen in this study warrants caution in the interpretation of results. We have demonstrated the impact of differing HU threshold values on the diagnostic ability of this test. We would propose a threshold of 135 HU to diagnose OP. Future work would investigate the optimal HU cut-off to differentiate normal from low bone mineral density.
Authors: Mary Lucy Marques; Nuno Pereira da Silva; Desirée van der Heijde; Monique Reijnierse; Xenofon Baraliakos; Juergen Braun; Floris A van Gaalen; Sofia Ramiro Journal: RMD Open Date: 2022-06