Which method can measure 100% trabecular bone at the spine?

• A. Single X-ray Absorptiometry (SXA)
• B. Quantitative Computed Tomography (QCT)
• C. Dual-energy X-ray Absorptiometry (DXA)
• D. Single Photon Absorptiometry (SPA)

Answer: (B)

Quantitative Computed Tomography (QCT) is a method that can specifically measure the trabecular bone within the spine with 100% accuracy. This technique utilizes computed tomography to differentiate between the cortical and trabecular components of bone, allowing for a detailed evaluation of bone density specifically in those areas where trabecular bone plays a key role, such as in the vertebrae.

In addition to its ability to assess trabecular bone, QCT can provide volumetric bone density measurements, which are beneficial in understanding the bone quality and structure more comprehensively than traditional methods. This capability makes QCT particularly valuable in the clinical assessment of osteoporosis and in evaluating fracture risk, as trabecular bone is more metabolically active and more susceptible to changes in bone density.

Other methods, such as Single X-ray Absorptiometry, Dual-energy X-ray Absorptiometry, and Single Photon Absorptiometry, primarily measure bone density in a way that may not solely target trabecular bone, especially in mixed regions where cortical bone is present. Hence, while these techniques offer important insights into overall bone health, they do not achieve the same specificity in trabecular bone measurement as QCT does, confirming the appropriateness of Q