DEXA and Imaging in Osteoporosis

Indian J Orthop. 2023 Dec 12;57(Suppl 1):82-93. doi: 10.1007/s43465-023-01059-2. eCollection 2023 Dec.

Abstract

Background: Reduced bone density and increased fragility are hallmarks of osteoporosis, making the disease a major public health concern. The disease necessitates early diagnosis and appropriate therapy depend on an accurate evaluation of bone health. Essential tools for assessing osteoporosis include dual-energy X-ray absorptiometry (DEXA) and other imaging modalities.

Methods: This chapter focuses on dual-energy X-ray absorptiometry (DEXA) and other imaging methods as essential tools for assessment of osteoporosis. The chapter also explores complementary imaging modalities that help overcome limitation of DEXA by providing insights into the microarchitecture and bone quality.

Results: T-scores, used to categorise bone health, are determined by DEXA by comparing bone mineral density to age-matched standards. Bone mineral density (BMD) is the most common indicator of bone health; nevertheless, DEXA may misclassify bone health owing to reasons other than BMD. These constraints may be overcome with the use of complementary imaging methods, which provide information on the microarchitecture and quality of bone. The evaluation of bone structure is aided by high-resolution peripheral quantitative computed tomography (HR-pQCT), which produces precise 3D images of the trabecular and cortical bone compartments. Independent of traditional methods of gauging fracture risk, quantitative ultrasonography (QUS) uses an analysis of the characteristics of sound waves to determine bone health. Diagnostic precision is improved by magnetic resonance imaging (MRI) due to its ability to view bone marrow and trabecular structure without the use of ionising radiation.

Discussion: New methods, such as the trabecular bone score (TBS), examine bone texture and provide more data on the likelihood of fracture than conventional DEXA. By modelling bone strength using imaging data, finite element analysis (FEA) provides a biomechanical viewpoint on breakage probability. These combined methods boost diagnostic accuracy and pave the way for individualised treatment plans. Imaging helps with therapy monitoring as well as diagnosis. By monitoring bone density and structure over time, therapy effectiveness or course corrections may be quickly identified. The availability of sophisticated imaging techniques and the standardisation of procedures provide obstacles not withstanding their advantages. Ongoing work is being done to solve these issues and standardise and disseminate these methods in a variety of contexts.

Conclusion: The evaluation of osteoporosis is significantly aided by DEXA and other imaging methods. While DEXA is still the gold standard for diagnosing osteoporosis, other imaging techniques may shed light on bone health in greater detail. These methods improve fracture risk prediction and treatment assessment by providing information on bone architecture, quality, and strength. Integration of several imaging modalities shows potential for bettering osteoporosis therapy and patient outcomes as the field develops.

Keywords: DEXA; Fracture risk; HR pQCT; Imaging methods in osteoporosis; Osteoporosis; Quantitative ultrasound.

Publication types

  • Review