Figure 5: Regions of the lumbar spine vertebra included in measurement of bone mineral density by DXA and QCT scans. In addition to the vertebral body, areal bone mineral density (aBMD) as assessed by DXA includes density measurement of the posterior processes (spinous process) as indicated by the background light gray square. Measurement of volumetric bone mineral density (vBMD) by QCT-scans includes only the central (trabecular) part of the vertebral body.