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Purpose: The vertebral bone quality (VBQ) score based on magnetic resonance imaging (MRI) was introduced as a bone quality marker in the lumbar spine. Prior studies showed that it could be utilized as a predictor of osteoporotic fracture or complications after instrumented spine surgery. The objective of this study was to evaluate the correlation between VBQ scores and bone mineral density (BMD) measured by quantitative computer tomography (QCT) in the cervical spine., Methods: Preoperative cervical CT and sagittal T1-weighted MRIs from patients undergoing ACDF were retrospectively reviewed and included. The VBQ score in each cervical level was calculated by dividing the signal intensity of the vertebral body by the signal intensity of the cerebrospinal fluid on midsagittal T1-weighted MRI images and correlated with QCT measurements of the C2-T1 vertebral bodies. A total of 102 patients (37.3% female) were included., Results: VBQ values of C2-T1 vertebrae strongly correlated with each other. C2 showed the highest VBQ value [Median (range) 2.33 (1.33, 4.23)] and T1 showed the lowest VBQ value [Median (range) 1.64 (0.81, 3.88)]. There was significant weak to moderate negative correlations between and VBQ Scores for all levels [C2: p < 0.001; C3: p < 0.001; C4: p < 0.001; C5: p < 0.004; C6: p < 0.001; C7: p < 0.025; T1: p < 0.001]., Conclusion: Our results indicate that cervical VBQ scores may be insufficient in the estimation of BMDs, which might limit their clinical application. Additional studies are recommended to determine the utility of VBQ and QCT BMD to evaluate their potential use as bone status markers., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Objective: Osteoporosis is a metabolic bone disease that increases the risk for fragility fractures. Screening and diagnosis can be achieved by measuring bone mineral density (BMD) using quantitative CT tomography (QCT) in the lumbar spine. QCT-derived BMD measurements can be used to diagnose osteopenia or osteoporosis based on American College of Radiology (ACR) thresholds. Many reports exist regarding the disease prevalence in asymptomatic and disease-specific populations; however, osteoporosis/osteopenia prevalence rates in lumbar spine fusion patients without fracture have not been reported. The purpose of this study was to define osteoporosis and osteopenia prevalence in lumbar fusion patients using QCT., Methods: A retrospective review of prospective data was performed. All patients undergoing lumbar fusion surgery who had preoperative fine-cut CT scans were eligible. QCT-derived BMD measurements were performed at L1 and L2. The L1-2 average BMD was used to classify patients as having normal findings, osteopenia, or osteoporosis based on ACR criteria. Disease prevalence was calculated. Subgroup analyses based on age, sex, ethnicity, and history of abnormal BMD were performed. Differences between categorical groups were calculated with Fisher's exact test., Results: Overall, 296 consecutive patients (55.4% female) were studied. The mean age was 63 years (range 21-89 years). There were 248 (83.8%) patients with ages ≥ 50 years. No previous clinical history of abnormal BMD was seen in 212 (71.6%) patients. Osteopenia was present in 129 (43.6%) patients and osteoporosis in 44 (14.9%). There were no prevalence differences between sex or race. Patients ≥ 50 years of age had a significantly higher frequency of osteopenia/osteoporosis than those who were < 50 years of age., Conclusions: In 296 consecutive patients undergoing lumbar fusion surgery, the prevalence of osteoporosis was 14.9% and that for osteopenia was 43.6% diagnosed by QCT. This is the first report of osteoporosis disease prevalence in lumbar fusion patients without vertebral fragility fractures diagnosed by QCT.

Background Context: It has been reported that degenerative disc disease (DDD) is associated with higher spinal bone mineral density (BMD) based on previous studies that used dual X-ray absorptiometry (DXA). However, DDD is often associated with proliferative bone changes and can lead to an overestimation of BMD measured with DXA. Trabecular volumetric BMD (vBMD) in the vertebral body measured with quantitative computed tomography (QCT) is less affected by those changes and can be a favorable alternative to DXA for patients with degenerative spinal changes., Purpose: The purpose of this study is to investigate the effect of DDD on regional trabecular vBMDs in the vertebral body measured by QCT., Study Design/setting: Cross-sectional observational study at a single academic institution., Patients Sample: Consecutive patients undergoing posterior lumbar spinal fusion between 2014 and 2017 who had a routine preoperative CT scan and magnetic resonance imaging (MRI) within a 90-day interval., Outcome Measures: Regional trabecular vBMDs in the vertebral body by QCT., Methods: QCT measurements were conducted in L1-S1 vertebral trabecular bone. Any apparent sclerotic lesions that might affect vBMD values were excluded from the region of interest. The vBMDs of each level were defined as the average vBMD of the upper and lower vertebrae. To evaluate DDD, Pfirrmann grade, Modic grade, total end plate score, and vacuum phenomenon were documented. Univariate regression analysis and multivariate analyses with a linear mixed model adjusted with individual variability of segmental vBMDs were conducted with vBMD as the response variable., Results: Of 143 patients and 715 disc levels, 125 patients and 596 discs met our inclusion criteria. Mean vBMD (±standard deviation [SD]) of all levels was 119.0±39.6 mg/cm 3 . After adjusting for all covariates, Pfirrmann grade was not an independent contributor to vBMD, but the presence of any Modic change (type 1, β=6.8, p≤.001; type 2, β=6.7, p<.001; type 3, β=43.6, p<.001), high TEPS (score 10-12, β=14.2, p<.001), or vacuum phenomenon (β=9.0, p<.001) was shown to be independent contributors to vBMD., Conclusions: Our results showed that the presence of certain end plate lesions (Modic changes and high TEPS) on MRI was significantly associated with increased regional QCT-vBMDs in the vertebral body, but no significant association was observed with disc nucleus pathology, unless it was associated with a vacuum phenomenon. When end plate lesions with Modic changes and high TEPS are present at the measuring level, care must be taken to interpret vBMD values, which might be overestimations even if the trabecular area appears normal., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Background Context: Quantitative computed tomography (QCT) of the lumbar spine is used as an alternative to dual-energy X-ray absorptiometry in assessing bone mineral density (BMD). The average BMD of L1-L2 is the standard reportable metric used for diagnostic purposes according to current recommendations. The density of L1 and L2 has also been proposed as a reference value for the remaining lumbosacral vertebrae and is commonly used as a surrogate marker for overall bone health. Since regional BMD differences within the spine have been proposed, it is unclear if the L1-L2 average correlates with the remainder of the lumbosacral spine., Purpose: The aim of this study was to determine possible BMD variations throughout the lumbosacral spine in patients undergoing lumbar fusion and to assess the correlation between the clinically used L1-L2 average and the remaining lumbosacral vertebral levels., Study Design/setting: This is a retrospective case series., Patient Sample: Patients undergoing posterior lumbar spinal fusion from 2014 to 2017 at a single, academic institution with available preoperative CT imaging were included in this study., Outcome Measures: The outcome measure was BMD measured by QCT., Methods: Standard QCT measurements at the L1 and L2 vertebra and additional experimental measurements of L3, L4, L5, and S1 were performed. Subjects with missing preoperative lumbar spine CT imaging were excluded. The correlations between the L1-L2 average and the other vertebral bodies of the lumbosacral spine (L3, L4, L5, S1) were evaluated., Results: In total, 296 consecutive patients (55.4% female, mean age of 63.1 years) with available preoperative CT were included. The vertebral BMD values showed a gradual decrease from L1 to L3 and increase from L4 to S1 (L1=118.8 mg/cm 3 , L2=116.6 mg/cm 3 , L3=112.5 mg/cm 3 , L4=122.4 mg/cm 3 , L5=135.3 mg/cm 3 , S1=157.4 mg/cm 3 ). There was strong correlation between the L1-L2 average and the average of the other lumbosacral vertebrae (L3-S1) with a Pearson's correlation coefficient (r=0.85). We also analyzed the correlation between the L1-L2 average and each individual lumbosacral vertebra. Similar relationships were observed (r value, 0.67-0.87), with the strongest correlation between the L1-L2 average and L3 (r=0.87)., Conclusions: Our data demonstrate regional BMD differences throughout the lumbosacral spine. Nevertheless, there is high correlation between the clinically used L1-L2 average and the BMD values in the other lumbosacral vertebrae. We, therefore, conclude the standard clinically used L1-L2 BMD average is a useful bone quantity measure of the entire lumbosacral spine in patients undergoing lumbar spinal fusion., (Copyright © 2018. Published by Elsevier Inc.)