Dear editor
Further to the recent publication on the “Repeated vertebral augmentation for new vertebral compression fractures of postvertebral augmentation patients: a nationwide cohort study”,1 current data highlight the limitations of dual-energy X-ray absorptiometry scans. In this context, at best, dual-energy X-ray absorptiometry scans (which measure bone mineral density) can account for no greater than 50% of overall bone strength (defined as the ability to resist fracture). This is because the resulting images are two-dimensional and therefore unable to capture skeletal micro-architecture, which also contributes to bone strength.2
A better clinical measure of overall bone strength that more accurately reflects the ability of that bone to resist fracture and hence fracture risk reflect an unmet need and is urgently required. Recent evidence suggests that micro-computed tomography scans, which enable three-dimensional imaging, might provide a solution but use so far has necessarily been limited to ex vivo assessment owing to radiation hazards as well as technical and accessibility issues.3,4 However micro-computed tomography images have identified bone volume fraction (the volumetric distribution of bone mass) as a strong determinant of bone strength (r2>0.8).5,6
Further, perhaps other potential tools, alone or in combination with imaging may also play a role. For example, serum biomarkers of bone metabolism7,8 along with other imaging modalities such as magnetic resonance imaging could capture the complex factors that make up bone strength.9 Preexisting algorithms like the FRAX (a fracture risk assessment tool calculator)10 might help reduce the overprediction issue currently faced.
With regard to the aforementioned evidence, there is a pressing need to consider first how we use bone densitometry in the diagnosis of osteoporosis in prostate cancer patients, before the National Health Service itself becomes fractured.
Footnotes
Disclosure
The authors report no conflicts of interest in this communication.
References
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