PT  - JOURNAL ARTICLE
AU  - Odeh, Khalid
AU  - Rosinski, Alexander
AU  - Mittal, Ashish
AU  - Wu, Wei
AU  - Pourtabib, Joseph
AU  - Leasure, Jeremi
AU  - Kondrashov, Dimitriy G.
TI  - Does the Bone Mineral Density of the Lumbar Spine Correlate With Dual-Energy X-ray Absorptiometry <em>T</em> Score? A Cadaveric-Based Analysis of Computed Tomography Densitometry
AID  - 10.14444/8388
DP  - 2023 Feb 01
TA  - International Journal of Spine Surgery
PG  - 132--138
VI  - 17
IP  - 1
4099  - https://www.ijssurgery.com/content/17/1/132.short
4100  - https://www.ijssurgery.com/content/17/1/132.full
SO  - Int J Spine Surg2023 Feb 01; 17
AB  - Background Pedicle screw loosening is a complication of spinal instrumentation in osteoporotic patients. Dual-energy x-ray absorptiometry scans are not able to detect variations in bone mineral density (BMD) within specific regions of vertebrae. The purpose of this study was to investigate whether spine T scores correlate with cortical and cancellous BMD of pedicles and other 6 anatomical regions of lumbar spine.Methods Eleven cadaveric spines with a mean age of 73 years were digitally isolated by applying filters for cortical and cancellous bone on computed tomography images. Eleven L5 vertebrae were separated into 7 anatomical regions of interest using 3-dimensional software modeling. Hounsfield units (HU) were determined for each region and converted to cortical and cancellous BMD with calibration phantoms of known BMD. Correlations between T scores and HU values were calculated using Pearson correlation coefficient.Results Mean vertebral T score was 0.15. Cortical BMD of pedicles was strongly correlated with T score (R 2 = 0.74). There was moderate correlation between T score and cortical BMD of lamina, inferior articular process (IAP), superior articular process (SAP), spinous process, and vertebral body. There was weak correlation between T score and cortical BMD of transverse process (R 2 = 0.16). Cancellous BMD of vertebral body was strongly correlated with T score (R 2 = 0.82). There was moderate correlation between T score and cancellous BMD of pedicles, spinous process, and transverse process. There was weak correlation between T scores and cancellous BMD of lamina, IAP, and SAP.Conclusions There is a strong correlation between T scores and cortical BMD of lumbar pedicle. There is strong correlation between T scores and cancellous BMD of vertebral body. Cortical and cancellous BMD of transverse process and lamina were weakly correlated with T score and less affected by osteoporosis.Clinical Relevance Patients with osteoporosis may especially benefit from the development of extrapedicular fusion strategies due to the relatively higher bone density of these fixation sites.