Trabecular bone density in the proximal femur: quantitative CT assessment. Work in progress

A new technique has been developed for quantitative assessment of trabecular bone content in the proximal femur using computed tomography (CT). The method employs the same contoured calibration phantom currently used for vertebral mineral studies and can be performed on any standard body scanner. Both femurs are evaluated simultaneously, and an integral approach to mean density determinations compensates for the complex geometry and trabecular architecture of the region. Specimen studies have documented acceptable reproducibility, and radiation dose and examination time are comparable to those of quantitative CT in the spine. Greater inherent accuracy has been achieved more rapidly through the addition of three-dimensional histogram analysis using a free-standing CT data processor. High correlation with vertebral trabecular bone content has been documented in the limited number of patients studied to date. Widespread availability of the technique and the high frequency of fractures related to metabolic bone disease in the proximal femur render the method a potentially valuable contribution to noninvasive bone densitometry.