Background: Accurate diagnosis of osteoporosis relies on precise measurement of bone mass and assessment of bone micro-architecture. However, the application of Bone Mineral Density (BMD) as the sole criterion of osteoporosis may not reflect all fractions of the bones. In this study, we retrospectively analysed the association between the mean CT value of different bone fractions and ages, and discussed the quantitative diagnosis of osteoporosis.
Methods: The thin-slice Computed Tomography (CT) scans of the lumbar vertebrae of 862 patients were retrospectively reviewed. The patients were divided into the Pathological Fracture (PF) group (n=107) and the Non-Pathological Fracture (NPF) group (n=755). The NPF group was further divided into 7 subgroups with a 10-year-increment. The vertebral bodies were divided into the overall vertebral bodies (Min-Max HU), the cancellous bone (Min-661HU) and the compact bone (662-Max HU) to investigate their mean CT values. The correlation between these parameters and age were analysed. The parameters of the PF group and the NPF subgroups were compared using the ANOVA analysis.
Results: The mean CT values of the overall vertebral bodies (R2, 0.76-0.79) and the cancellous bone (R2, 0.84-0.85) were negatively correlated with patient’s age, while that of the compact bone was only 0.25-0.36. There were significant differences in the mean CT values between PF group and the NPF subgroups (P<0.05).
Conclusion: The mean CT value of the cancellous bone, which reflect the true bone density, correlate well with the age, and might be promising candidates in the quantitative and differential diagnosis of osteoporosis and the bone fracture risk assessment.