Abstract
Introduction
Sacral bone mineral density may play a role in the rate successful sacroiliac and lumbosacral fusions. There are currently no easy methods for evaluation of sacral bone mineral density. Lumbar CTattenuation has previously been shown to relate to bone mineral density as assessed by DXA. This study aims to establish an accessible method for sacral bone mineral density analysis.
Study Design/Setting
A retrospective review of renalprotocol CT scans performed for any indication over a three-month period in 2014. CTattenuation was analyzed at several regions of interest within each scan.
Materials and Methods
A retrospective review of renalprotocol CT scans performed for any indication over a three-month period in 2014. A series of 223 consecutive renalprotocol CT scans were analyzed using basic image viewing software. Sacral CTattenuation at multiple regions of interest (ROI) were compared with the L1 attenuation to determine if a correlation existed. The sacral ROI were analyzed to determine regions of higher and lower attenuation. Sacral attenuation was also analyzed by age and sex.
Results
All sacral ROI had strong correlations with lumbar spine attenuation values, and these values became even stronger when transitional vertebrae were excluded. Sacral attenuation values varied predictably by location. Sacral attenuation was inversely related to age. No difference was found in sacral attenuation by sex.
Conclusions
Sacral CTattenuation can be used in opportunistic CT scans to determine sacral bone mineral density. This method can be used in the future to evaluate the impact of sacral bone mineral density on successful sacroiliac and lumbosacral fusions.