Preoperative MRI-based vertebral bone quality (VBQ) score assessment in patients undergoing lumbar spinal fusion

Adding Vertebral Bone Quality to the Fusion Risk Score: Does It Improve Predictions of Postoperative Complications?

STUDY DESIGN

Retrospective review of prospectively collected data.

OBJECTIVE

The current study evaluates whether the addition of the Vertebral Bone Quality (VBQ) score to the Fusion Risk Score (FRS) improves its ability to predict perioperative outcomes.

SUMMARY OF BACKGROUND DATA

The FRS was developed to assess preoperative risk in patients undergoing thoracic and lumbar fusions. It includes patient-derived and surgical variables, but it does not include one that directly accounts for bone health. The VBQ score allows assessment of bone quality and has been shown to correlate to DEXA-measured bone mineral density (BMD) scores.

METHODS

The VBQ score was weighted based on a regression model and then added to the FRS (FRS/VBQ). The ability of the two scores to predict the outcomes was then assessed using the area under the curve (AUC).

PATIENT SAMPLE

Patients undergoing elective thoracic and lumbar spinal fusion from January 2019 to June 2020 were included.

OUTCOME MEASURES

The study evaluated various perioperative adverse outcomes, including major and minor adverse events, discharge other than home, extended length of stay, 90-day emergency department visits, 90-day readmission, and 90-day and 2-year reoperation rates.

RESULTS

A total of 353 met the inclusion and exclusion criteria. The FRS/VBQ demonstrated improved predictive ability compared with the FRS alone when evaluating 90-day reoperation. Both scores showed fair predictive ability for any adverse event, major adverse events, minor adverse events, and 2-year reoperation rates, with AUCs ranging from 0.700 to 0.737. Both had poor predictive ability for the other outcomes.

CONCLUSIONS

Adding VBQ to the FRS significantly enhances its predictive accuracy for reoperation rate. This updated risk score provides a more comprehensive understanding of a patient's preoperative risk profile, aiding both patients and physicians in assessing surgical risks and optimizing outcomes through preoperative risk stratification.

LEVEL OF EVIDENCE

3.

MRI-based Pedicle Bone Quality score: Correlation to Quantitative Computed Tomography Bone Mineral Density and its Role in Quantitative Assessment of Osteoporosis

BACKGROUND CONTEXT

Bone quality in the pedicle region generally determines screw pullout strength, insertion torque, and vertebral body loading characteristics. Dual-energy X-ray absorptiometry (DEXA), as the gold standard for evaluating bone mineral density (BMD), cannot measure the BMD of specific parts, such as pedicle, and DEXA is limited in many ways. Recent studies have shown a correlation between the magnetic resonance imaging (MRI)-based vertebral bone quality (VBQ) score and BMD measured using DEXA or quantitative computed tomography (QCT). However, no studies have been reported on the MRI-based pedicle bone quality (PBQ) score. Moreover, few studies have investigated the relationship between MRI-based PBQ and osteoporosis.

PURPOSE

To create a new site-specific MRI-based PBQ assessment method and assess its diagnostic capacity in patients with normal BMD and osteopenia/osteoporosis.

STUDY DESIGN/SETTING

A retrospective study.

PATIENT SAMPLE

A total of 156 patients underwent lumbar fusion surgery for chronic low back pain at our hospital between 2021 and 2022, with lumbar QCT and T1-weighted MRI performed before surgery.

OUTCOME MEASURES

Correlation of the PBQ score with QCT BMD, and the association between the PBQ score and presence of osteopenia/osteoporosis.

METHODS

BMD of the lumbar was calculated as the mean BMD of the L1 and L2 vertebral bodies on the basis of asynchronous QCT measurements. The PBQ score, which is the average of the bone quality values of both pedicles on the basis of site-specific T1-weighted sagittal MRI images, was calculated by dividing the median signal intensity of the L1-L4 pedicles by the signal intensity of the cerebrospinal fluid at the L3 level. The interobserver reliability of the PBQ score was assessed using the intraclass correlation coefficient (ICC). A receiver operating characteristic curve was drawn, and the area under the curve (AUC) was calculated to assess the predictive performance of PBQ for osteoporosis. The PBQ score was compared with QCT BMD, as the gold standard, using Pearson correlation analysis.

RESULTS

In total, 156 patients participated in this study, including 51 in the Normal BMD group and 105 in the osteopenia/osteoporosis group. The PBQ score in the osteopenia/osteoporosis group was significantly higher than that in the normal BMD group (3.19 ± 0.55 vs. 2.84 ± 0.51, p < 0.001). The VBQ and PBQ scores were calculated by two authors and were in good agreement (intraclass correlation coefficient = 0.949 and 0.929, respectively). Pearson's test showed a significant negative correlation between PBQ and QCT BMD (r = -0.4887, p < 0.001). The optimal cutoff PBQ score to differentiate patients with osteopenia/osteoporosis from those with normal BMD was 3.160, with a sensitivity of 66.7%, specificity of 72.5%, and AUC of 0.776. The PBQ score correlated more strongly with QCT BMD (r = -0.4887) than VBQ (r = -0.4078).

CONCLUSIONS

In this study, we propose a novel, MRI-based pedicle-specific bone quality score. This is the first study to investigate the relationship between the PBQ score and QCT BMD. The PBQ score showed diagnostic utility, differentiating between patients with osteopenia/osteoporosis and those with normal BMD (AUC = 0.776), and the PBQ score correlated more strongly with QCT BMD than VBQ.

Correlations among MRI-based cervical and thoracic vertebral bone quality score, CT-based Hounsfield Unit score, and DEXA t-score in assessment of bone mineral density

BACKGROUND

Further optimization of the validated vertebral bone quality (VBQ) score using magnetic resonance imaging (MRI) may expand its clinical utility for bone mineral density (BMD) assessment. This study evaluated the correlations among cervical and thoracic VBQ scores, the validated Hounsfield Unit (HU) measured on computed tomography (CT), and dual-energy x-ray absorptiometry (DEXA) values.

METHODS

We retrieved the medical and radiographic records of 165 patients who underwent synchronous MRI of the cervical and thoracic spine, as well as DEXA and CT imaging of the spine obtained within 1 year of each other between 2015 and 2022. Radiographic data consisted of the MRI-based cervical and thoracic VBQ scores, CT-based HU, and DEXA T-scores of the spine and hip. Patient age, sex, body mass index (BMI), and ethnicity were also obtained.

RESULTS

Mean cervical and thoracic VBQ scores were 3.99 ± 1.68 and 3.82 ± 2.11, respectively. Mean HU and DEXA T-scores of the spine and hip were 135.75 ± 60.36, -1.01 ± 1.15, and -0.47 ± 2.27. All correlations among VBQ, HU, and DEXA were insignificant except for weak correlations between cervical and thoracic VBQ, and cervical VBQ and HU. No correlations were observed between radiographic scores and patient age or BMI. No differences based on ethnicity or sex were observed with respect to cervical or thoracic VBQ, HU, or DEXA.

CONCLUSION

Cervical and thoracic VBQ scores are distinct from Hounsfield Unit and DEXA values. VBQ scoring in the cervical and thoracic spine is not influenced by patient age, ethnicity, sex, or BMI.

Comparison of predictive value for cage subsidence between MRI-based endplate bone quality and vertebral bone quality scores following transforaminal lumbar interbody fusion: a retrospective propensity-matched study

BACKGROUND CONTEXT

Cage subsidence after lumbar fusion can lead to many adverse outcomes. Low bone mineral density (BMD) is a widely recognized risk factor for cage subsidence. Conventional methods can predict and evaluate BMD, but there are many shortcomings. Recently, MRI-based assessment of bone quality in specific parts of the vertebral body has been proposed, including scores for vertebral bone quality (VBQ) and endplate bone quality (EBQ). However, the predictive accuracy of the two scoring systems for cage subsidence after transforaminal lumbar interbody fusion (TLIF) remains unknown. Therefore, we investigated MRI-based VBQ and EBQ scores for assessing bone quality and compared their predictive value for cage subsidence after TLIF.

PURPOSE

To compare the predictive value between MRI-based VBQ and EBQ scores for cage subsidence after TLIF.

STUDY DESIGN/SETTING

A retrospective case-control study.

PATIENTS SAMPLE

Patients with degenerative lumbar diseases underwent single-level TLIF at our medical center between 2014 and 2020, all of whom had preoperative MRIs available.

OUTCOMES MEASURES

Cage subsidence, disc height, VBQ score, EBQ score, upper and lower vertebral body bone quality (UL-VBQ) score.

METHODS

Data were retrospectively examined for a consecutive sample of 346 patients who underwent TLIF at our medical center between 2014 and 2020. Patients who subsequently experienced cage subsidence or not were matched to each other based on propensity scoring, and the two matched groups (52 patients each) were compared using conditional logistic regression to investigate the association between the potential radiographic factors and cage subsidence. Scores for VBQ and EBQ were assessed for their ability to predict cage subsidence in the matched patients based on the area under the receiver operative characteristic curve (AUC).

RESULTS

Among matched patients, those who suffered cage subsidence had significantly higher VBQ score (3.7 vs 3.1, p<.001) and EBQ score (5.0 vs 4.3, p<.001), and regression linked greater risk of subsidence to higher VBQ score (OR 4.557, 95% CI 1.076-19.291, p=.039) and higher EBQ score (OR 5.396, 95% CI 1.158-25.146, p=.032). A cut-off VBQ score of 3.4 predicted the cage subsidence among matched patients with an AUC of 0.799, sensitivity of 84.6%, and specificity of 69.2%. A cut-off EBQ score of 4.7 predicted subsidence with an AUC of 0.829, sensitivity of 76.9%, and specificity of 82.7%.

CONCLUSION

Higher VBQ and EBQ scores are associated with a greater risk of cage subsidence following TLIF, and EBQ may perform better because of greater specificity.

MRI-based vertebral bone quality score as a novel bone status marker of patients with adolescent idiopathic scoliosis

To investigate the application of MRI-based vertebral bone quality (VBQ) score in assessing bone mineral density (BMD) for patients with adolescent idiopathic scoliosis (AIS). We reviewed the data of AIS patients between January 2021 and October 2023 with MRI, whole-spine plain radiographs, quantitative computed tomography (QCT) and general information. VBQ score was calculated using T1-weighted MRI. Univariate analysis was applied to present the differences between variables of patients with normal BMD group (QCT Z-score > - 2.0) and low BMD group (QCT Z-score ≤ - 2.0). The correlation between VBQ score and QCT Z-score was analyzed with Pearson correlation test. A multivariate logistic regression model was used to determine the independent factors related to low BMD. Receiver operating characteristic curve (ROC) was drawn to analyze the diagnostic performance of VBQ score in distinguishing low BMD. A total of 136 AIS patients (mean age was 14.84 ± 2.10 years) were included, of which 41 had low BMD. The low BMD group had a significantly higher VBQ score than that in normal group (3.48 ± 0.85 vs. 2.62 ± 0.62, P < 0.001). The VBQ score was significantly negative correlated with QCT Z score (r =  - 0.454, P < 0.001). On multivariate analysis, VBQ score was independently associated with low BMD (OR: 4.134, 95% CI 2.136-8.000, P < 0.001). The area under the ROC curve indicated that the diagnostic accuracy of the VBQ score for predicting low BMD was 81%. A sensitivity of 65.9% with a specificity of 88.4% could be achieved for distinguishing low BMD by setting the VBQ score cutoff as 3.18. The novel VBQ score was a promising tool in distinguishing low BMD in patients with AIS and could be useful as opportunistic assessment for screening and complementary evaluation to QCT before surgery.

MRI-based endplate bone quality score predicts cage subsidence following oblique lumbar interbody fusion

BACKGROUND CONTEXT

Cage subsidence is a common complication after lumbar interbody fusion surgery, with low bone mineral density (BMD) being a significant risk factor. ໿Endplate bone quality (EBQ) obtained from clinical MRI scans has been deemed reliable in determining regional BMD. However, the association between EBQ score and cage subsidence following oblique lumbar interbody fusion (OLIF) has not been clearly established.

PURPOSE

This study aims to assess the relationship between EBQ score and cage subsidence in patients who underwent single-level OLIF.

STUDY DESIGN/SETTING

A retrospective study.

PATIENT SAMPLE

The study included adults with degenerative spinal conditions who underwent single-level OLIF at our institution.

OUTCOME MEASURES

Cage subsidence, disc height, EBQ score, fusion rate.

METHODS

This retrospective study analyzed data from patients who underwent single-level OLIF surgery at our institution between October 2017 and August 2022. Postoperative CT scans were used to measure cage subsidence, while the EBQ score was calculated using preoperative non-contrast T1-weighted MRI. To determine the predictive ability of the EBQ score, receiver operating characteristic (ROC) curve analysis was conducted. Additionally, univariable and multivariable logistic regression analyses were performed.

RESULTS

In this study, a total of 88 patients were included and followed up for an average of 15.8 months. It was observed that 32.9% (n=29/88) of the patients experienced cage subsidence. The post-surgery disc height was significantly higher in patients who experienced subsidence compared to those who did not. The mean EBQ scores for patients with non-subsidence and subsidence were 2.31±0.6 and 3.48±1.2, respectively, and this difference was statistically significant. The ROC curve analysis showed that the AUC for the EBQ score was 0.811 (95% CI: 0.717-0.905). The most suitable threshold for the EBQ score was determined to be 2.318 (sensitivity: 93.1%, specificity: 55.9%). Additionally, the multivariate logistic regression analysis revealed a significant association between a higher EBQ score and an increased risk of subsidence (odds ratio [OR]=6.204, 95% CI=2.520-15.272, p<.001).

CONCLUSIONS

Our findings indicate that higher preoperative EBQ scores are significantly linked to cage subsidence following single-level OLIF. Preoperative measurement of MRI can serve as a valuable tool in predicting cage subsidence.

Abdominal aortic calcification is an independent predictor of perioperative blood loss in posterior spinal fusion surgery

OBJECTIVE

Abdominal aortic calcification (AAC), often found incidentally on lateral lumbar radiographs, is increasingly recognized for its association with adverse outcomes in spine surgery. As a marker of advanced atherosclerosis affecting cardiovascular dynamics, this study evaluates AAC's impact on perioperative blood loss in posterior spinal fusion (PSF).

METHODS

Patients undergoing PSF from March 2016 to July 2023 were included. Estimated blood loss (EBL) and total blood volume (TBV) were calculated. AAC was assessed on lateral lumbar radiographs according to the Kauppila classification. Predictors of the EBL-to-TBV ratio (%EBL/TBV) were examined via univariable and multivariable regression analyses, which adjusted for parameters such as hypertension and aspirin use.

RESULTS

A total of 199 patients (47.2% female) were analyzed. AAC was present in 106 patients (53.3%). AAC independently predicted %EBL/TBV, accounting for an increase in blood loss of 4.46% of TBV (95% CI 1.17-7.74, p = 0.008).

CONCLUSIONS

This is the first study to identify AAC as an independent predictor of perioperative blood loss in PSF. In addition to its link to degenerative spinal conditions and adverse postoperative outcomes, the relationship between AAC and increased blood loss warrants attention in patients undergoing PSF.

Preoperative Assessment of Bone Density Using MRI-Based Vertebral Bone Quality Score Modified for Patients Undergoing Cervical Spine Surgery

STUDY DESIGN

Diagnostic accuracy study.

OBJECTIVES

Previous studies have reported the clinical application of the Vertebral Bone Quality (VBQ) scores for assessing bone density in operative lumbar spine patients. We aim to explore whether the method could be modified and applicable for patients undergoing cervical spine surgery.

METHODS

Adult patients receiving cervical spine surgery for degenerative diseases between September 2020 and March 2022 with non-contrast T1-weighted MRI and DEXA were included. Correlation between cervical VBQ scores and DEXA T-scores was analyzed using Pearson's correlation. Student's t test was used to present the discrepancy between the VBQ of patients with normal bone density (T ≥ -1.0) and patients with osteopenia/osteoporosis (T < -1.0). Statistical significance was set at P < .05.

RESULTS

Eighty-three patients (20 patients with T ≥ -1.0 vs 63 patients with T < -1.0 ) were included. Significant difference was found between the cervical VBQ between groups (2.99 ± .79 vs 3.80 ± .81, P < .001). Interclass correlation coefficient for inter-rater reliability was .82 (95% CI: .70-.93) and .91(95% CI: .84-.97) for intra-rater reliability. The area under the ROC curve was .78 (95% CI: .65-.90). The DEXA T-score of the femoral neck, total hip and the lowest DEXA T-score were found to be significantly correlated with the cervical VBQ score according to Pearson correlation analysis (P < .001).

CONCLUSIONS

This is the first study to apply the VBQ method to assess the bone density in preoperative cervical spine patients. Cervical VBQ scores were significantly correlated with DEXA T-score. With an overall accuracy of .78, the radiation-free and cost-effective method could be a potential tool for screening patients with osteopenia and osteoporosis before surgery.

S1 vertebral bone quality score independently predicts pedicle screw loosening following surgery in patients with adult degenerative scoliosis

BACKGROUND CONTEXT

MRI-based vertebral bone quality (VBQ) score is an effective predictor of pedicle screw loosening after lumbar fusion surgery and has been recognized as a valuable tool for assessing preoperative bone quality. Due to the lateral curvature of lumbar spine of degenerative scoliosis, accurate measurement of VBQ score by conventional measurement methods that capture MRI signal intensity at L1-4 may be limited under certain conditions. To this end, a new simplified S1 VBQ score method has been proposed, which is comparable to the previous L1-4 VBQ score or S1 Hounsfield unit (HU) value, and has high accuracy and reliability.

PURPOSE

To evaluate the predictive value of MRI-based S1 VBQ score for pedicle screw loosening following surgery for adult degenerative scoliosis (ADS).

STUDY DESIGN/SETTING

Retrospective single-center cohort.

PATIENT SAMPLE

We reviewed 92 patients who underwent posterior lumbar interbody fusion (PLIF) with pedicle screw fixation for ADS between January 2017 and January 2020.

OUTCOME MEASURES

Association between S1 VBQ score and pedicle screw loosening following surgery for ADS.

METHODS

We retrospectively reviewed the records of all patients who performed PLIF between January 2017 and January 2020. The clear zone around pedicle screws≥1 mm can be identified as screw loosening. The S1 VBQ score is calculated from the S1 central-based non-contrast T1-weighted magnetic resonance imaging (MRI). The signal intensity (SI) of the cerebrospinal fluid (CSF) was then measured using ROI placed at the L3 level to normalize the results. Multivariate logistic regression analysis was performed to identify independent risk factors for screw loosening. Then, constructed a receiver operating characteristic (ROC) curve and determined the threshold (cut-off) of VBQ score with high sensitivity and specificity based on Youden Index.

RESULTS

A total of 92 patients were included, including 34 males and 58 females. The mean age of the patients was 61.23±1.23 years old. At 1-year follow-up, the screw loosening rate was 56.5% (52/92). The age and levels of fixation were higher in the loosening group than in the non-loosening group (p=.036, p=.025). Patients in the loosening group had a greater VBQ score compared to patients in the non-loosening group (3.31±0.41 vs 3.01±0.28, p=.001). Multivariate logistic regression analysis showed that advanced age (OR, 1.090; 95% CI 1.005-1.183; p=.039) and higher VBQ score (OR, 5.778; 95% CI 2.889-16.177; p=.001) were independent risk factors for screw loosening. In addition, the ROC curve were created to assess the role of VBQ score as predictors of screw loosening with a diagnostic accuracy of 74.6% (95% CI 64.2%-85.1%).The most suitable threshold for the VBQ score as determined by the Youden Index was 3.175 (sensitivity: 76.0%, specificity: 83.3%).

CONCLUSIONS

Higher S1 VBQ score was significantly associated with pedicle screw loosening following surgery for ADS. The S1 VBQ score can be used as an effective preoperative predictor, which has the potential clinical application.

A novel MRI-based Cervical-Endplate Bone Quality score independently predicts cage subsidence after Anterior Cervical Discectomy and Fusion

INTRODUCTION

Postoperative cage subsidence after Anterior Cervical Discectomy and Fusion (ACDF) often has adverse clinical consequences and is closely related to Bone Mineral Density (BMD). Previous studies have shown that cage subsidence can be better predicted by measuring site-specific bone density. MRI-based Endplate Bone Quality (EBQ) scoring effectively predicts cage subsidence after lumbar interbody fusion. However, there is still a lack of studies on the practical application of EBQ scoring in the cervical spine.

PURPOSE

To create a similar MRI-based scoring system for Cervical-EBQ (C-EBQ) and to assess the correlation of the C-EBQ with endplate Computed Tomography (CT)-Hounsfield Units (HU) and the ability of this scoring system to independently predict cage subsidence after ACDF, comparing the predictive ability of the C-EBQ with the Cervical-Vertebral Bone Quality (C-VBQ) score.

METHODS

A total of 161 patients who underwent single-level ACDF for degenerative cervical spondylosis at our institution from 2012 to 2022 were included. Demographics, procedure-related data, and radiological data were collected, and Pearson correlation test was used to determine the correlation between C-EBQ and endplate HU values. Cage subsidence was defined as fusion segment height loss of ≥ 3 mm. Receiver operating characteristic analysis and area-under-the-curve values were used to assess the predictive ability of C-EBQ and C-VBQ. A multivariate logistic regression model was developed to identify potential risk factors associated with subsidence.

RESULTS

Cage subsidence was present in 65 (40.4%) of 161 patients. The mean C-EBQ score was 1.81 ± 0.35 in the group without subsidence and 2.59 ± 0.58 in the group with subsidence (P < 0.001). Multivariate analysis showed that a higher C-EBQ score was significantly associated with subsidence (OR = 5.700; 95%CI = 3.435-8.193; P < 0.001), was the only independent predictor of cage subsidence after ACDF, had a predictive accuracy of 93.7%, which was superior to the C-VBQ score (89.2%), and was significantly negatively correlated with the endplate HU value (r = -0.58, P < 0.001).

CONCLUSIONS

Higher C-EBQ scores were significantly associated with postoperative cage subsidence after ACDF. There was a significant negative correlation between C-EBQ and endplate HU values. The C-EBQ score may be a promising tool for assessing preoperative bone quality and postoperative cage subsidence and is superior to the C-VBQ.

Improving Osteoporosis Prediction Using Vertebral Bone Quality Score and Paravertebral Muscle Measurements From Lumbar MRI Scans

STUDY DESIGN

Retrospective cohort.

OBJECTIVE

This study aims to use a novel method of combining vertebral bone quality score with paravertebral cross-sectional area measurements to improve the accuracy of predicting individuals with total hip T-scores <-2.5.

SUMMARY OF BACKGROUND DATA

Osteoporosis is a prevalent skeletal condition associated with decreased bone density and increased fracture risk. Dual-energy x-ray absorptiometry (DXA) is the conventional method for diagnosing osteoporosis, but it has limitations. Opportunistic osteoporosis screening techniques using lumbar magnetic resonance imaging (MRI), particularly the vertebral bone quality (VBQ) score, have shown promise. This study aims to improve the accuracy of predicting individuals with low total hip T-scores using a novel method that combines VBQ scores with paravertebral cross-sectional area (CSA) measurements.

METHODS

A retrospective cohort of 98 patients with DXA and lumbar MRI scans was analyzed. VBQ scores were calculated based on lumbar MRI images, and CSA measurements of paravertebral and psoas muscles were obtained. Threshold-based logistic regression was used to identify optimal thresholds for predicting total hip T-scores <-2.5.

RESULTS

The combined model incorporating the VBQ score and paravertebral muscle percent achieved an accuracy of 96.9% for predicting total hip T-scores <-2.5, compared to 81.6% when using the VBQ score alone. Incorporating paravertebral muscle measurements significantly improved the accuracy of identifying osteoporotic individuals.

CONCLUSIONS

The combination of VBQ score and paravertebral muscle measurements enhances the accuracy of predicting individuals with low total hip T-scores. Lumbar MRI scans provide valuable information beyond opportunistic osteoporosis screening, and the inclusion of paravertebral muscle measurements could aid in identifying at-risk individuals more accurately.

Evaluation of the modified MRI vertebral bone quality score for bone quality in lumbar degenerative disorders

OBJECTIVE

The traditional VBQ scoring method may lead to overestimation due to the concentration of intravertebral fat and vascular structures in the posterior half of vertebral bodies, potentially resulting in false-positive outcomes. This study aims to modify the measurement method of VBQ score (Modified-VBQ) and evaluate its effectiveness in evaluating bone quality of lumbar degenerative diseases.

METHODS

Retrospective analysis was conducted on clinical data from patients undergoing lumbar surgery for degenerative diseases between September 2022 and September 2023. Preoperative lumbar t1-weighted Magnetic resonance imaging was used for both modified and traditional VBQ scoring. Computed tomography (CT) images and dual-energy X-ray absorptiometry (DEXA) data were collected through the picture archiving and communication system. The effectiveness of the modified VBQ score was evaluated, considering P < 0.05 as statistically significant.

RESULTS

The study included 212 patients, revealing a significant difference between the modified VBQ and VBQ scores (P < 0.0001). Notably, patients with a history of hyperlipidemia exhibited a significant difference between the two scores (P = 0.0037). The area under the ROC curve (AUC) for the modified VBQ was 0.86, surpassing the VBQ score (AUC = 0.74). Linear regression analysis demonstrated a moderate to strong correlation between the modified VBQ and DEXA T-score (r = - 0.49, P < 0.0001) and a high correlation with CT Hounsfield units (HU) values (r = - 0.60, P < 0.0001).

CONCLUSION

The modified VBQ score provides a simple, effective, and relatively accurate means of assessing bone quality in lumbar degenerative diseases. Preoperative implementation of the modified VBQ score facilitates rapid screening for patients with abnormal bone quality.

Comparison of the predictive values of MRI-based vertebral bone quality scores for the determination of osteoporosis in different diseases

PURPOSE

The study aimed to examine the consistency of vertebral bone quality (VBQ) scores for assessing osteoporosis across different etiologies and explore the predictive value of various VBQ scores for fragility vertebral fractures.

METHODS

Patients with fragility fractures were matched by age and sex to patients with lumbar degeneration. VBQ scores were calculated in T1- and T2-weighted magnetic resonance imaging. Differential analysis of bone quality was performed based on etiology.

RESULTS

A total of 96 inpatients were retrospectively enrolled. VBQT1 scores were only sensitive to osteoporotic bone in degenerative group (p < 0.01), failing to identify osteoporosis in fractured group (p > 0.05). For the degenerative group, the area under the curve (AUC) using the VBQT1 scores to differentiate osteoporosis was 0.72. After controlling the confounding variables, only VBQT2 scores were significantly higher in fractured group than degenerative group, with a greater AUC of 0.82 predicting fragility fractures. VBQT1 scores moderately correlated with femoral neck T-scores in degenerative group (r = -0.45, p < 0.01) but not in fractured group (r = -0.24, p > 0.05). VBQT2 scores were not associated with femoral neck T-scores (p > 0.05).

CONCLUSION

This study is the first to evaluate the effectiveness of VBQs scores in assessing osteoporosis post-fracture. Only non-fractured patients' bone quality is fully susceptible to VBQT1 scores. While VBQT1 scores may not correlate with fragility fractures, VBQT2 scores present a viable alternative.

Bone mineral density in lower thoracic vertebra for osteoporosis diagnosis in older adults during CT lung cancer screening

BACKGROUND

Quantitative computed tomography (QCT)-based lumbar bone mineral density (LBMD) has been used to diagnose osteoporosis. This study explored the value of lower thoracic BMD (TBMD) in diagnosing osteoporosis in older adults during CT lung cancer screening.

METHODS

This study included 751 subjects who underwent QCT scans with both LBMD and TBMD. 141 of them was selected for a validation. Osteoporosis was diagnosed based on LBMD using the ACR criteria (gold standard). TBMD thresholds were obtained using receiver operating characteristic curve. TBMD was also translated into LBMD (TTBMD) and osteoporosis was defined based on TTBMD using ACR criteria. The performance of TBMD and TTBMD in identifying osteoporosis was determined by Kappa test. The associations between TBMD- and TTBMD-based osteoporosis and fracture were tested in 227 subjects with followed up status of spine fracture.

RESULTS

The performance of TBMD in identifying osteoporosis was low (kappa = 0.66) if using the ACR criteria. Two thresholds of TBMD for identifying osteopenia (128 mg/cm3) and osteoporosis (91 mg/cm3) were obtained with areas under the curve of 0.97 and 0.99, respectively. The performance of the identification of osteoporosis/osteopenia using the two thresholds or TTBMD both had good agreement with the gold standard (kappa = 0.78, 0.86). Similar results were observed in validation population. Osteoporosis identified using the thresholds (adjusted hazard ratio (HR) = 18.72, 95% confidence interval (CI): 5.13-68.36) or TTBMD (adjusted HR = 10.28, 95% CI: 4.22-25.08) were also associated with fractures.

CONCLUSION

Calculating the threshold of TBMD or normalizing TBMD to LBMD are both useful in identifying osteoporosis in older adults during CT lung cancer screening.

Using advanced imaging to measure bone density, compression fracture risk, and risk for construct failure after spine surgery

Low bone mineral density (BMD) can predispose to vertebral body compression fractures and postoperative instrumentation failure. DEXA is considered the gold standard for measurement of BMD, however it is not obtained for all spine surgery patients preoperatively. There is a growing body of evidence suggesting that more routinely acquired spine imaging studies such as computed tomography (CT) and magnetic resonance imaging (MRI) can be opportunistically used to measure BMD. Here we review available studies that assess the validity of opportunistic screening with CT-derived Hounsfield Units (HU) and MRI-derived vertebral vone quality (VBQ) to measure BMD of the spine as well the utility of these measures in predicting post-operative outcomes. Additionally, we provide screening thresholds based on HU and VBQ for prediction of osteopenia/ osteoporosis and post-operative outcomes such as cage subsidence, screw loosening, proximal junctional kyphosis, and implant failure.

Comparative Analysis of the 3 Cervical Vertebral Bone Quality (C-VBQ) Score Methodologies and Their Correlations to the Lumbar Vertebral Bone Quality (VBQ) Score

OBJECTIVE

Common complications after spinal fusion, such as pseudoarthrosis, cage subsidence, or instrumentation failure, are affected by patients' bone quality. The cervical-vertebral bone quality (C-VBQ) score, a magnetic resonance imaging (MRI)-based adaption of the lumbar vertebral bone quality (VBQ) score, was developed by 3 separate research groups simultaneously to evaluate bone quality in cervical spinal fusion patients. We present the first analysis comparing these scoring methods to the well-validated VBQ score.

METHODS

A retrospective analysis of data for consecutive patients who underwent spine surgery at a single institution was completed. The VBQ score was calculated using the Ehresman et al.

METHOD

The C-VBQ scores, named according to placement of the region of interest within the cerebral spinal fluid, were calculated separately using the methods of Soliman et al. (C2-VBQ), Razzouk et al. (C5-VBQ), and Huang et al. (T1-VBQ). Linear regression models were utilized to evaluate correlations to the VBQ score.

RESULTS

A total of 105 patients were identified (mean age, 57.0 ± 11.9 years; women, 50.5%). Mean scores were C2-VBQ, 2.37 ± 0.55; C5-VBQ, 2.36 ± 0.61; and T1-VBQ, 2.64 ± 0.68. The C-VBQ scores for the C2 level were significantly higher than those for the C3-C6 levels (3.18 ± 0.96 vs. 2.63 ± 0.77, P < 0.001), whereas the C7 level was found to have significantly lower C-VBQ scores (2.42 ± 0.78 vs. 2.63 ± 0.77, P = 0.04). The C2-VBQ (r = 0.63) score had the strongest correlation to the VBQ score, compared to C5-VBQ (r = 0.41) and T1-VBQ (r = 0.43) (P < 0.001).

CONCLUSIONS

This study demonstrates that the C2-VBQ had the strongest correlation to the lumbar VBQ score among all C-VBQ scores.

MRI‑based vertebral bone quality score is a comprehensive index reflecting the quality of bone and paravertebral muscle

BACKGROUND

Recently, vertebral bone quality (VBQ) score has been shown to predict bone mineral density (BMD) and spine-related postoperative complications. However, in clinical work, we found that patients with higher VBQ scores also had more severe paravertebral muscle degeneration.

PURPOSE

To explore the ability of the VBQ score to evaluate BMD and paravertebral muscle quality.

STUDY DESIGN/SETTING

Retrospective single-center cohort.

PATIENT SAMPLE

Patients in the spinal surgery department of our hospital.

OUTCOME MEASURES

Bone mineral density and T-score were measured by dual-energy X-ray absorptiometry (DXA). The Picture Archiving and Communication Systems (PACS) measured the cross-sectional area (CSA) of the paravertebral muscles. Image J software was used to measure the degree of fat infiltration (DFF) of the paraspinal muscle.

METHODS

Patients who underwent lumbar MRI and DXA simultaneously within two weeks were enrolled. The VBQ score was calculated using T1-weighted lumbar MRI images. Firstly, BMD-related and muscle-related parameters of patients with different VBQ scores were compared. Then, the correlation coefficients between the VBQ score and the parameters of BMD and paravertebral muscle were calculated. Finally, multivariate linear analysis was used to compare the contribution of each variable to the VBQ score.

RESULTS

A total of 101 patients were eventually included in this study for analysis. When the VBQ score was greater than 3.0, the patients were mostly female, older, less likely to smoke, and had lower BMD. Interestingly, we found that patients with VBQ scores greater than 3.0 had smaller CSA of the paravertebral muscles (ES: 17.53±3.36 vs 19.13±3.97, p=.032; total: 29.59±5.27 vs 34.12±7.02, p<.001) and higher DFF (MF: 22.47±5.93 vs 19.64±5.28, p=.015; ES: 17.71±4.67 vs 15.74±4.62, p=.038; PM: 13.70±3.32 vs 11.33±3.02, p<.001; average: 17.96±3.78 vs 15.57±3.42, p=.001). The VBQ score was negatively correlated with the CSA (MF: r=-0.316, p=.001; ES: r =-0.388, p=.001; PM: r=0.388, p=.001) and positively correlated with the DFF (MF: r=0.344, p<.001; ES: r=0.439, p<.001; PM: =0.416, p<.001). In multivariate linear analysis, BMD, total CSA, and average DFF determined the value of the VBQ score, and the contribution of paravertebral muscle was higher than that of BMD (BMD: r=-0.203, p=.024; total CSA: r=-0.294, p=.003; average DFF: r=0.261, p=.011).

CONCLUSIONS

This study is the first to find a positive association between the VBQ score and paravertebral muscle degeneration, and this association may be independent of BMD. VBQ can reflect the quality of bone and paravertebral muscle, which is its special advantage in clinical application.

Vertebral Bone Quality Score as a Predictor of Adjacent Segment Disease After Lumbar Interbody Fusion

BACKGROUND AND OBJECTIVE

With lumbar spine fusion being one of the most commonly performed spinal surgeries, investigating common complications such as adjacent segment disease (ASD) is a high priority. To the authors' knowledge, there are no previous studies investigating the utility of the preoperative magnetic resonance imaging-based vertebral bone quality (VBQ) score in predicting radiographic and surgical ASD after lumbar spine fusion. We aimed to investigate the predictive factors for radiographic and surgical ASD, focusing on the predictive potential of the VBQ score.

METHODS

A single-center retrospective analysis was conducted of all patients who underwent 1-3 level lumbar or lumbosacral interbody fusion for lumbar spine degenerative disease between 2014 and 2021 with a minimum 12 months of clinical and radiographic follow-up. Demographic data were collected, along with patient medical, and surgical data. Preoperative MRI was assessed in the included patients using the VBQ scoring system to identify whether radiographic ASD or surgical ASD could be predicted.

RESULTS

A total of 417 patients were identified (mean age, 59.8 ± 12.4 years; women, 54.0%). Eighty-two (19.7%) patients developed radiographic ASD, and 58 (13.9%) developed surgical ASD. A higher VBQ score was a significant predictor of radiographic ASD in univariate analysis (2.4 ± 0.5 vs 3.3 ± 0.4; P < .001) and multivariate analysis (odds ratio, 1.601; 95% CI, 1.453-1.763; P < .001). For surgical ASD, a significantly higher VBQ score was seen in univariate analysis (2.3 ± 0.5 vs 3.3 ± 0.4; P < .001) and served as an independent risk factor in multivariate analysis (odds ratio, 1.509; 95% CI, 1.324-1.720; P < .001). We also identified preoperative disk bulge and preoperative existence of adjacent segment disk degeneration to be significant predictors of both radiographic and surgical ASD. Furthermore, 3-level fusion was also a significant predictor for surgical ASD.

CONCLUSION

The VBQ scoring system might be a useful adjunct for predicting radiographic and surgical ASD.

The Significance of Combined OSTA, HU Value and VBQ Score in Osteoporosis Screening Before Spinal Surgery

OBJECTIVE

This study aimed to assess the utility of a combined assessment using the Osteoporosis Self-Assessment Tool for Asians (OSTA), Hounsfield unit (HU) value, and vertebral bone quality (VBQ) score for preoperative osteoporosis (OP) screening in patients scheduled for spinal surgery.

METHODS

This study encompassed 288 participants, including 128 males and 160 females. Patients were stratified into 2 groups: the OP group (T-score ≤ -2.5) and the non-OP group (T-score > -2.5), determined by dual-energy X-ray absorptiometry (DEXA). Binary logistic regression was used to construct a combined diagnostic model, and the receiver operating characteristic (ROC) curve evaluated the sensitivity, specificity, accuracy, positive predictive value (PPV), and negative predictive value (NPV) of these metrics individually or in combination to screen for OP.

RESULTS

Osteoporosis patients exhibited significantly lower OSTA and HU values in comparison to non-OP patients, while their VBQ scores were significantly higher (P < 0.001). The ROC curve analysis results indicated that within the male group, the combined diagnosis had a sensitivity of 93.8%, specificity of 82.3%, accuracy of 85.2%, PPV of 63.8%, and NPV of 97.5%. In the female group, the combined diagnosis had a sensitivity of 93.9%, specificity of 87.4%, accuracy of 90.0%, PPV of 83.6%, and NPV of 95.4%.

CONCLUSIONS

The combined use of OSTA, HU values, and VBQ scores in preoperative OP screening for spinal surgery demonstrates significantly higher accuracy and superior screening value compared to individual assessments. These results establish a robust scientific foundation for conducting preoperative OP screening in patients undergoing spinal surgery.

Assessing the utility of MRI-based vertebral bone quality (VBQ) for predicting lumbar pedicle screw loosening

STUDY DESIGN

Retrospective cohort.

OBJECTIVE

The purpose of this study is to assess the potential of utilizing the MRI-based vertebral bone quality (VBQ) score as a predictive tool for pedicle screw loosening (PSL) in patients who have undergone pedicle screw fixation and to identify risk factors associated with VBQ scores.

METHODS

One hundred and sixteen patients who had undergone pedicle screw fixation between December 2019 and January 2021 and had more than a year of follow-up were divided into two groups of PSL and non-PSL. The radiological and clinical parameters investigated were age, gender, body mass index, the VBQ score, length of fusion and the DXA T-score.

RESULTS

Of the 116 patients included in the study, 22 patients developed pedicle screw loosening after surgery (18.97%). VBQ score of PSL group was higher than the non-PSL group (3.61 ± 0.63 vs. 2. 86 ± 0.43, p < 0.001). According to logistic regression, PSL was independently linked with a higher VBQ score (OR = 3.555, 95% confidence interval [1.620-7.802], p < 0.005). The AUC of predicting screw loosening was 0.774 (p < 0.001) for VBQ score, and the best threshold was 3.055 (sensitivity, 81.8%; specificity, 71.3%). High VBQ score was associated with age (r (114) = 0.29, p = 0.002), while it was not negatively correlated with T-scores of each part.

CONCLUSION

VBQ score is an independent predictor of pedicle screw loosening, with higher scores indicating a greater risk. Our results showed that older patients and women had higher VBQ scores.

Comparison of Long-term Follow-Up of n-HA PA66 Cage and PEEK Cage of Lumbar Interbody Fusion in Multi-level Degenerative Lumbar Diseases: A Stepwise Propensity Score Matching Analysis

OBJECTIVE

Previous studies have confirmed that the nanohydroxyapatite/polyamide-66 (n-HA/PA66) cage is an ideal alternative material for degenerative lumbar disease (DLD) comparable to the polyether ether ketone (PEEK) cage due to its similar radiographic fusion, subsidence rate, and clinical results. However, these studies were restricted to one-level surgery. The aim of this study was to analyze the long-term clinical and radiologic outcomes between n-HA PA66 cage and PEEK cage for patients with multi-level degenerative lumbar diseases (DLDs).

METHODS

We retrospectively reviewed all patients who underwent multi-level transforaminal lumbar interbody fusion (TLIF) from June 2010 to December 2016 with a minimum 6-year follow-up. Matched-pair analysis was performed using a 1-to-1 closest neighbor approach to match patients who received an n-HA PA66 cage with those who received a PEEK cage. Clinical outcomes and radiographic evaluations were compared between the two groups. The independent student's t-test and χ2 -test were applied to compare the differences between groups.

RESULTS

At the end of the propensity score matching (PSM) analysis, 48 patients from n-HA/PA66 group were matched to 48 patients in the PEEK group. No significant difference was observed in cage subsidence and bony fusion except for adjacent segment degeneration (ASD). The occurrence of ASD was 14.58% (7/48) in the n-HA/PA 66 group, which was significantly less than that in the PEEK group (33.33% [16/48]) (p = 0.031). Although the intervertebral space height (IH), segmental angle (SA) and lumbar lordosis (LL) significantly increased after surgery in both groups, there was no significant difference at any time point after surgery (p > 0.05). The visual analogue scale (VAS) and Oswestry disability index (ODI) scores significantly improved in both groups at 3m postoperative, 1y postoperative and at final follow-up. However, there were no significant differences in the VAS and ODI score at any time point (p > 0.05). The total complications and re-admission rate were not different between the two groups.

CONCLUSION

Overall, our data suggest that the outcomes of n-HA/PA66 cage group are comparable to those of the PEEK cage group, with a similar high fusion rate and low cage subsidence rate as PEEK cages, except its lower rate of ASD occurrence.

Which Indicator Among Lumbar Vertebral Hounsfield Unit, Vertebral Bone Quality, or Dual-Energy X-Ray Absorptiometry-Measured Bone Mineral Density Is More Efficacious in Predicting Thoracolumbar Fragility Fractures?

OBJECTIVE

Hounsfield units (HU), vertebral bone quality (VBQ), and bone mineral density (BMD) can all serve as predictive indicators for thoracolumbar fragility fractures. This study aims to explore which indicator provides better risk prediction for thoracolumbar fragility fractures.

METHODS

Patients who have received medical attention from The First Affiliated Hospital of Anhui Medical University for thoracolumbar fragility fractures were selected. A total of 78 patients with thoracolumbar fragility fractures were included in the study. To establish a control group, 78 patients with degenerative spinal diseases were matched to the fracture group on the basis of gender, age, and body mass index. The lumbar vertebral HU, the VBQ, and the BMD were obtained for all the 156 patients through computed tomography, magnetic resonance imaging, and dual-energy x-ray absorptiometry (DEXA). The correlations among these parameters were analyzed. The area under curve (AUC) analysis was employed to assess the predictive efficacy and thresholds of lumbar vertebral HU, VBQ, and BMD in relation to the risk of thoracolumbar fragility fractures.

RESULTS

Among the cohort of 156 patients, lumbar vertebral HU exhibited a positive correlation with BMD (p < 0.01). Conversely, VBQ showed a negative correlation with HU, BMD (p < 0.05). HU and BMD displayed a favorable predictive efficacy for thoracolumbar fragility fractures (p < 0.01), with HU (AUC = 0.863) showcasing the highest predictive efficacy, followed by the DEXA-measured BMD (AUC = 0.813). VBQ (AUC = 0.602) ranked lowest among the 3 indicators. The thresholds for predicting thoracolumbar fragility fractures were as follows: HU (88),VBQ (3.37), and BMD (0.81).

CONCLUSION

All 3 of these indicators, HU, VBQ, and BMD, can predict thoracolumbar fragility fractures. Notably, lumbar vertebral HU exhibits the highest predictive efficacy, followed by the BMD obtained through DEXA scanning, with VBQ demonstrating the lowest predictive efficacy.

MRI-based vertebral bone quality score: relationship with age and reproducibility

Vertebral bone quality (VBQ) score is an opportunistic measure of bone mineral density using routine preoperative MRI in spine surgery. VBQ score positively correlates with age and is reproducible across serial scans. However, extrinsic factors, including MRI machine and protocol, affect the VBQ score and must be standardized.

PURPOSE

The purposes of this study were to determine whether VBQ score increased with age and whether VBQ remained consistent across serial MRI studies obtained within 3 months.

METHODS

This retrospective study evaluated 136 patients, age 20-69, who received two T1-weighted lumbar MRI within 3 months of each other between January 2011 and December 2021. VBQ(L1-4) score was calculated as the quotient of L1-L4 signal intensity (SI) and L3 cerebral spinal fluid (CSF) SI. VBQ(L1) score was calculated as the quotient of L1 SI and L1 CSF SI. Regression analysis was performed to determine correlation of VBQ(L1-4) score with age. Coefficient of variation (CV) was used to determine reproducibility between VBQ(L1-4) scores from serial MRI scans.

RESULTS

One hundred thirty-six patients (mean ± SD age 44.9 ± 12.5 years; 53.7% female) were included in this study. Extrinsic factors affecting the VBQ score included patient age, MRI relaxation time, and specific MRI machine. When controlling for MRI relaxation/echo time, the VBQ(L1-4) score was positively correlated with age and had excellent reproducibility in serial MRI with CV of 0.169. There was excellent agreement (ICC > 0.9) of VBQ scores derived from the two formulas, VBQ(L1) and VBQ(L1-4).

CONCLUSION

Extrinsic factors, including MRI technical factors and age, can impact the VBQ(L1-4) score and must be considered when using this tool to estimate bone mineral density (BMD). VBQ(L1-4) score was positively correlated with age. Reproducibility of the VBQ(L1-4) score across serial MRI is excellent especially when controlling for technical factors, supporting use of the VBQ score in estimating BMD. The VBQ(L1) score was a reliable alternative to the VBQ(L1-4) score.

Evaluating Surgical Cervical Arthrodesis With a Novel MRI Grading Score

STUDY DESIGN

This was a single-institution retrospective study.

OBJECTIVE

Evaluate a magnetic resonance imaging (MRI)-scoring system to differentiate arthrodesis from pseudoarthrosis following anterior cervical discectomy and fusion.

SUMMARY OF BACKGROUND DATA

Diagnostic workup following fusion surgery often includes MRI to evaluate neural structures and computed tomography (CT) and/or dynamic x-rays to evaluate instrumentation and arthrodesis. The use of MRI alone for these evaluations would protect patients from harmful CT and x-ray ionizing radiation.

METHODS

Neurosurgical attending evaluated CTs for arthrodesis or pseudoarthrosis. Blinded neuroradiology attending and neurosurgery senior resident evaluated independent T1 and T2 region of interest (ROI) signal intensity over instrumented disk space. Cerebral spinal fluid (CSF) at the cisterna magnum and distal adjacent uninstrumented vertebral body (VB) were also calculated. ROI interspace /ROI CSF and ROI interspace /ROI VB quotients were used to create T1- and T2-interspace interbody scores (IIS).

RESULTS

Study population (n=64 patients, 50% female) with a mean age of 51.72 years and 109 instrumented levels with 45 fused levels (41.3%) were included. T1-weighted MRI, median T1-IIS CSF for arthrodesis was 176.20 versus 130.92 for pseudoarthrosis ( P <0.0001), T1-IIS VB for arthrodesis was 68.52 and pseudoarthrosis was 52.71 ( P <0.0001). T2-weighted MRI, median T2-IIS CSF for arthrodesis was 27.72 and 14.21 for pseudoarthrosis ( P <0.0001), while T2-IIS VB for arthrodesis was 67.90 and 41.02 for pseudoarthrosis ( P <0.0001). The greatest univariable discriminative capability for arthrodesis via AUROC was T1-IIS VB (0.7743).

CONCLUSION

We describe a novel MRI scoring system that may help determine arthrodesis versus pseudoarthrosis following anterior cervical discectomy and fusion. Postoperative symptomatic patients may only require MRI, which would protect patients from ionizing radiation.

LEVEL OF EVIDENCE

Level IV.

A meta-analysis of the value of MRI-based VBQ scores for evaluating osteoporosis

Objective

Osteoporosis is the most common skeletal disease in humans. Early onset of osteoporosis is usually asymptomatic, so early diagnosis is critical. The purpose of this study was to analyze the value of MRI-based VBQ scores for evaluating osteoporosis.

Methods

We searched PubMed, Embase, the Cochrane Library databases, Web of Science, and some Chinese electronic databases for published articles and the ClinicalTrials.gov site for completed but unpublished studies on evaluating the value of MRI-based VBQ scores for evaluating osteoporosis. We calculated the summarized sensitivity, specificity, the ROC curve (AUC) values and their 95% confidence intervals (CIs) using MetaDiSc 1.4 software and STATA.

Results

Our study included 8 studies involving 999 patients of which 660 patients were diagnosed with osteopenia/osteoporosis, and 339 patients were identified as having normal BMD. The pooled sensitivity was 0.809 (95% CI, 0.777-0.838, I 2  = 78.8%), the pooled specificity was 0.640 (95% CI, 0.587-0.691, I 2  = 85.9%), and the pooled AUC was 0.8375.

Conclusion

MRI-based VBQ scores provided high sensitivity and moderate specificity in detecting osteoporosis. Opportunistic use of VBQ scores could be considered, e.g. before lumbar spine surgery.

Prospero registration number

CRD42022377024.

MRI-based Endplate Bone Quality score independently predicts cage subsidence following transforaminal lumbar interbody fusion

BACKGROUND CONTEXT

Cage subsidence following transforaminal lumbar interbody fusion (TLIF) has closely correlated with poor vertebral bone quality. Studies have shown better predictive value for cage subsidence by measuring bone density at specific site. However, few studies have been performed to examine the relationship between site-specific MRI bone assessment and cage subsidence in patients who have undergone lumbar interbody fusion. The association between MRI-based assessment of endplate bone quality and cage subsidence after TLIF remains unclear.

PURPOSE

To study the predictive value of MRI-based endplate bone quality (EBQ) score for cage subsidence following TLIF, using QCT bone densitometry as a reference standard.

STUDY DESIGN/SETTING

A retrospective study.

PATIENT SAMPLE

A total of 280 adult patients undergoing single-segment TLIF for degenerative lumbar spine disease from 2010 to 2020 at our institution who had preoperative T1-weighted MRIs.

OUTCOME MEASURES

Cage subsidence, disc height, endplate bone quality (EBQ) score, bone mineral density, fusion rate.

METHODS

The retrospective study reviewed patients who underwent TLIF at one institution between March 2010 and October 2020. Cage subsidence was measured with postoperative lumbar X-rays based on the cage protrusion through into the superior or inferior end plate or both by more than 2 mm. The EBQ score was measured from preoperative T1-weighted MRI in accordance with the previously reported method.

RESULTS

Cage subsidence was observed in 42 of the 280 patients. Bone densitometry with quantitative computed tomography was visibly reduced in the subsidence group. The mean EBQ scores of the lumbar endplate bone was 4.3±0.9 in nonsubsidence and 5.0±0.6 in subsidence. On multivariate logistic regression, the difference between the two groups was remarkable. Risk of cage subsidence increases significantly with higher EBQ scores (odds ratio [OR]=2.063, 95% confidence interval [CI] 1.365-3.120, p=.001) and was an independent factor in predicting subsidence after TLIF. On receiver operating characteristic curve, the AUC for the EBQ score was 0.820 (95% confidence interval [CI]: 0.755-0.844) and the most suitable threshold for the EBQ score was 4.730 (sensitivity: 76.2%, specificity: 83.2%).

CONCLUSIONS

Higher EBQ scores measured on preoperative MRI correlated significantly with cage subsidence following TLIF. Performing EBQ assessment prior to TLIF may be a valid method of predicting the risk of postoperative subsidence.

MRI-based Vertebral Bone Quality Score for Osteoporosis Screening Based on Different Osteoporotic Diagnostic Criteria Using DXA and QCT

In this study, we aim to evaluate the correlation between T score measured by dual X-ray absorptiometry (DXA), volumetric bone mineral density (vBMD) derived from quantitative computed tomography (QCT) and MRI-based vertebral bone quality (VBQ), explore the diagnostic performance of VBQ in osteoporosis and determine the recognition value of VBQ in osteoporotic fracture in a relatively large cohort of elderly patients scheduled to undergo spinal surgery. A total of 260 patients were enrolled in the study. DXA and QCT were used to evaluate osteoporotic status. We calculated the lumbar VBQ score, analyzed the correlation between T score, vBMD and VBQ, and explored whether VBQ was an influential factor of bone quality and fracture by binary logistic regression as well as the diagnostic performance of VBQ in osteoporosis and fracture by ROC curve. VBQ was negatively correlated with vBMD and T score. (r = - 0.487 vs. r = - 0.220). The VBQ score was a risk factor for osteoporosis under the QCT diagnostic criteria (OR = 2.245, 95% CI 1.456-3.460) and osteoporotic fractures (OR = 1.496, 95% CI 1.097-2.040). It exhibited superior discriminant performance for osteoporosis diagnosed by QCT, with a cutoff value of 3.70 and an AUC of 0.7354. Its cutoff value for osteoporotic fractures was 3.72, and its AUC was 0.6717. In a cohort of elderly patients scheduled to undergo spinal surgery, the VBQ score was more strongly associated with vBMD than the T score and could identify patients with osteoporosis and corresponding vertebral compression fracture (VCF).

MRI-based vertebral bone quality score for predicting cage subsidence by assessing bone mineral density following transforaminal lumbar interbody fusion: a retrospective analysis

PURPOSE

This is the first study to evaluate the predictive value of the vertebral bone quality (VBQ) score on cage subsidence after transforaminal lumbar interbody fusion (TLIF) in a Chinese population using the spinal quantitative computed tomography (QCT) as the clinical standard. Meanwhile, the accuracy of the MRI-based VBQ score in bone mineral density (BMD) measurement was verified.

METHODS

We performed a retrospective study of patients who underwent single-level TLIF from 2015 to 2020 with at least 1 year of follow-up. Cage subsidence was measured using postoperative radiographic images based on cage protrusion through the endplates more than 2 mm. The VBQ score was measured on T1-weighted MRI. The results were subjected to statistical analysis.

RESULTS

A total of 283 patients (61.1% of female) were included in the study. The subsidence rate was with 14.1% (n = 40), and the average cage subsidence was 2.3 mm. There was a significant difference in age, sex, VBQ score and spinal QCT between the subsidence group and the no-subsidence group. The multivariable analysis demonstrated that only an increased VBQ score (OR = 2.690, 95% CI 1.312-5.515, p = 0.007) and decreased L1/2 QCT-vBMD (OR = 0.955, 95% CI 0.933-0.977, p < 0.001) were associated with an increased rate of cage subsidence. The VBQ score was found to be moderately correlated with the spinal QCT (r = -0.426, p < 0.001). The VBQ score was shown to significantly predict cage subsidence, with an accuracy of 82.5%.

CONCLUSION

Our findings indicate that the MRI-based VBQ score is a significant predictor of cage subsidence and could be used to assess BMD.

Assessing lumbar vertebral bone quality: a methodological evaluation of CT and MRI as alternatives to traditional DEXA

PURPOSE

The purpose of this study was to investigate the impact of various methods on the assessment of vertebral bone quality.

METHODS

A consecutive series of 427 candidates for lumbar disc replacement with lumbar DEXA and MRI and/or CT scans were included. Two measurement techniques were used on CTs-a sagittal and axial. From axial images, the upper, mid, and lower portions of each vertebral body were measured. Four MRI vertebral bone quality (VBQ) calculations were generated using separate equations.

RESULTS

All CT measures were highly correlated with each other, regardless of measurement or calculation method (range 0.925-0.995). Sagittal measurements were highly correlated with axial (r = 0.928, p < 0.001). CT values were correlated with DEXA (range 0.446-0.534). There was no benefit to measuring multiple axial images of each vertebral body vs. just midbody (r = 0.441 and 0.455, respectively). No MRI VBQ values were highly correlated with DEXA (r =  -  0.103, p = 0.045). In receiver operating curve analysis, the area under the curve ranged from 0.539 to 0.558, indicating poor ability of VBQ to identify osteoporosis/osteopenia.

CONCLUSION

CT produced values more closely related to DEXA, while MRI was less reliable for osteoporosis/osteopenia screening. On CT, there was no benefit to making multiple measurements for each vertebral body to calculate a composite. Measuring sagittal CT images produced values similar to axial and required less time. While assessing bone quality from existing images rather than getting an additional DEXA scan is appealing, the methods of measuring these images needs standardization to maximize their utility.

Can the greater trochanter/femoral neck signal intensity ratio on coronal T1 weighted images of the hip differentiate normal-abnormal bone mineral density?

A simple index calculated by dividing the greater trochanter signal intensity by that of the femoral neck on coronal T1-weighted magnetic resonance images of the hip may be useful as an opportunistic screening tool to differentiate normal vs. abnormal bone mineral density.

PURPOSE

The aim of this study is to evaluate the efficacy of the greater trochanter/femoral neck (T/N) signal intensity (SI) ratio on T1 weighted images of the hip in differentiating patients with normal vs. abnormal bone mineral density (BMD) using hip dual-energy x-ray absorptiometry (DXA) as the reference.

METHODS

Three BMD groups according to the T score of the femoral neck (i.e., normal, osteopenia, and osteoporosis) were created, and 20 patients were included for each group. The T/N ratio was calculated by dividing the greater trochanter SI by that of the femoral neck on coronal T1-weighted images. Receiver-operator characteristic (ROC) analysis was performed to determine diagnostic efficacy.

RESULTS

The mean age was 59.2±9.4; there were 57 women and 3 men. The mean BMD was 0.67±0.14 g/cm2. The mean T/N ratio for the normal, osteopenia, and osteoporosis groups were 1.37 (±0.12), 1.19 (±0.10), and 1.18 (±0.13), respectively. When the osteopenia and osteoporosis groups were combined into one group, i.e., low BMD group, the mean T/N ratio was 1.18 (±0.11), and it was significantly different from that of the normal BMD group (p<0.00001). In ROC analysis, the area under curve (AUC) for the T/N ratio in the diagnosis of low BMD was 0.870. An optimal cutoff value of 1.28 was found for the differentiation of normal vs. abnormal BMD with 80% sensitivity and 80% specificity.

CONCLUSIONS

The T/N ratio seems to be effective at differentiating patients with normal vs. abnormal BMD and may help triage patients for additional evaluation.

Characteristics of MRI‑based vertebral bone quality scores in elderly patients with vertebral fragility fractures

OBJECTIVE

To explore the characteristics of vertebral bone quality (VBQ) scores in patients with vertebral fragility fractures, including VBQ score and single-level VBQ score, and evaluate their effectiveness as predictors.

METHODS

The VBQ scores were measured using T1-weighted MRI images. VBQ scores were compared in patients with different times of previous fragility fractures. In addition, patients with fractures were matched for age and sex with patients without fractures, and VBQ scores were compared between the two groups. Finally, the predictive efficiency of VBQ scores for vertebral fragility fractures was analyzed by the receiver-operator curve (ROC).

RESULTS

The average VBQ score and single-level VBQ score in patients with fractures were 3.48 ± 0.56 and 3.60 ± 0.60 and no difference among patients with different times of previous fractures. As for the age- and sex-matched patients, fracture patients had higher VBQ scores (VBQ score: 3.48 ± 0.56 vs. 2.88 ± 0.40, p < 0.001; single-level VBQ score: 3.60 ± 0.60 vs. 2.95 ± 0.44, p < 0.001). The AUCs using the VBQ score and single-level VBQ score to predict fragility fractures were 0.815 and 0.817, respectively. The optimal thresholds of the VBQ score and single-level VBQ score for predicting fragility fractures were 3.22 and 3.16, respectively.

CONCLUSION

MRI‑based VBQ scores are important predictors of vertebral fragility fracture but have no predictive value for the recurrence of fractures in patients with a history of fragility fractures. The VBQ score of 3.22 and single-level VBQ score of 3.16 are optimal thresholds that can be used when using lumbar MRI scans to identify individuals at high risk for fragility fractures.

Assessment of bone density using the 1.5 T or 3.0 T MRI-based vertebral bone quality score in older patients undergoing spine surgery: Does field strength matter?

BACKGROUND CONTEXT

Recently published studies have revealed a correlation between MRI-based vertebral bone quality (VBQ) score and bone mineral density (BMD) measured using dual X-ray absorptiometry (DXA) or quantitative computed tomography (QCT). However, no studies have determined if differences in field strength (1.5 vs. 3.0 T) could affect the comparability of the VBQ score among different individuals.

PURPOSE

To compare the VBQ score obtained from 1.5 T and 3.0 T MRI (VBQ_1.5T versus VBQ_3.0T) in patients undergoing spine surgery and assess the predictive performance of VBQ for osteoporosis and osteoporotic vertebral fracture (VCF).

DESIGN

A nested case‒control study based on an ongoing prospective cohort study of patients undergoing spine surgery.

PATIENT SAMPLE

All older patients (men aged > 60 years and postmenopausal women) with available DXA, QCT and MR images within one month were included.

OUTCOME MEASURES

VBQ score, DXA T-score, and QCT derived vBMD.

METHODS

The osteoporotic classifications recommended by the World Health Organization and American College of Radiology were used to categorize the DXA T-score and QCT-derived BMD, respectively. For each patient, the VBQ score was calculated using T1-weighted MR images. Correlation analysis between VBQ and DXA/QCT was performed. Receiver operating characteristic (ROC) curve analysis, including determination of the area under the curve (AUC), was performed to assess the predictive performance of VBQ for osteoporosis.

RESULTS

A total of 452 patients (98 men aged > 60 years and 354 postmenopausal women) were included in the analysis. Across different BMD categories, the correlation coefficients between the VBQ score and BMD ranged from -0.211 to -0.511, and the VBQ_1.5T score and QCT BMD demonstrated the strongest correlation. The VBQ score was a significant classifier of osteoporosis detected by either DXA or QCT, with VBQ_1.5T showing the highest discriminative power for QCT-osteoporosis (AUC = 0.744, 95% CI = 0.685-0.803). In ROC analysis, the VBQ_1.5T threshold values ranged from 3.705 to 3.835 with a sensitivity between 48% and 55.6% and a specificity between 70.8% and 74.8%, while the VBQ_3.0T threshold values ranged from 2.59 to 2.605 with a sensitivity between 57.6% and 67.1% and a specificity between 67.8% and 69.7%.

CONCLUSIONS

VBQ_1.5T exhibited better discriminability between patients with and without osteoporosis than VBQ_3.0T. Considering the nonnegligible difference in osteoporosis diagnosis threshold values between the VBQ_1.5T and VBQ_3.0T scores, it is essential to clearly distinguish the magnetic field strength when assessing the VBQ score.

Vertebral bone quality score to predict cage subsidence following oblique lumbar interbody fusion

BACKGROUND

Current evidence suggests that the magnetic resonance imaging (MRI)-based vertebral bone quality (VBQ) score is a good parameter for evaluating bone quality. We aimed to assess whether the VBQ score can predict the occurrence of postoperative cage subsidence after oblique lumbar interbody fusion (OLIF) surgery.

METHODS

Patients (n = 102) who had undergone single-level OLIF with a minimal follow-up for 1 year were reviewed in this study. Demographic and radiographic data of these patients were collected. Cage subsidence was defined as ≥ 2 mm of cage migration into the inferior endplate, superior endplate, or both. Further, the MRI-based VBQ score was measured on T1-weighted images. Moreover, univariable and multivariable binary logistic regression analyses were performed. Meanwhile, Pearson analysis was used to evaluate the correlation among the VBQ score, average lumbar dual-energy X-ray absorptiometry (DEXA) T-score, and degree of cage subsidence. Furthermore, ad-hoc analysis was used along with receiver operating characteristic curve analysis to assess the predictive ability of the VBQ score and average lumbar DEXA T-score.

RESULTS

Of 102 participants, cage subsidence was observed in 39 (38.24%) patients. According to the univariable analysis, patients with subsidence had older age, higher antiosteoporotic drug use, larger disk height change, a more concave morphology of inferior and superior endplates, higher VBQ score, and lower average lumbar DEXA T-score compared to patients without subsidence. In the multivariable logistic regression analysis, a higher VBQ score was significantly associated with an increased risk of subsidence (OR = 23.158 ± 0.849, 95% CI 4.381-122.399, p < 0.001), and it was the only significant and independent predictor of subsidence after OLIF. Moreover, the VBQ score was moderately correlated with the average lumbar DEXA T-score (r = - 0.576, p < 0.001) and the amount of cage subsidence (r = 0.649, p < 0.001). Furthermore, this score significantly predicted cage subsidence with an accuracy of 83.9%.

CONCLUSIONS

The VBQ score can independently predict postoperative cage subsidence in patients undergoing OLIF surgery.

MRI-based vertebral bone quality score for the assessment of osteoporosis in patients undergoing surgery for lumbar degenerative diseases

PURPOSE

To explore the value of vertebral bone quality (VBQ) scores in diagnosing osteoporosis in patients with lumbar degeneration.

METHODS

A retrospective analysis was conducted of 235 patients treated with lumbar fusion surgery at the age of ≥ 50; they were divided into a degenerative group and a control group according to the severity of degenerative changes on three-dimensional computed tomography. The L1-4 vertebral body and L3 cerebrospinal fluid signal intensities in the T1-weighted lumbar magnetic resonance imaging (MRI) image were recorded, and the VBQ score was calculated. Demographics, clinical data, and dual-energy X-ray absorptiometry (DXA) indicators were recorded, and the VBQ value was compared with bone density and T-score using the Pearson correlation coefficient. The VBQ threshold was obtained according to the control group and compared with the efficacy of osteoporosis diagnosis based on DXA.

RESULTS

A total of 235 patients were included in the study, and the age of the degenerative group was older than that of the control group (61.8 vs. 59.4, P = 0.026). The VBQ score of the control group suggested a higher correlation with the bone mineral density (BMD) value and T-score (r = - 0.611 and - 0.62, respectively). The BMD value and T-score in the degenerative group were higher than those in the control group (P < 0.05). Receiver-operating characteristic curve analysis showed that the VBQ score had a good predictive ability for osteoporosis (AUC = 0.818), with a sensitivity of 93% and a specificity of 65.4%. Among the undiagnosed osteoporosis patients with T-score, the VBQ score after adjusting the threshold was higher in the degenerative group (46.9% vs. 30.8%).

CONCLUSIONS

Emerging VBQ scores can reduce the interference caused by degenerative changes compared to traditional DXA measures. Screening for osteoporosis in patients undergoing lumbar spine surgery provides new ideas.

Use of MRI-based vertebral bone quality score (VBQ) of S1 body in bone mineral density assessment for patients with lumbar degenerative diseases

PURPOSE

To evaluate the use of the modified and simplified vertebral bone quality (VBQ) method based on T1-weighted MRI images of S1 vertebrae in assessing bone mineral density (BMD) for patients with lumbar degenerative diseases.

METHODS

We reviewed the preoperative data of patients with lumbar degenerative diseases undergoing lumbar spine surgery between January 2019 and June 2022 with available non-contrast T1-weighted magnetic resonance imaging (MRI), computed tomography (CT) images and dual-energy X-ray absorptiometry (DEXA). S1 vertebral bone quality scores (S1 VBQ) and S1 CT Hounsfield units were measured with picture archiving and communication system (PACS). One-way ANOVA was applied to present the discrepancy between the S1 VBQ of patients with normal bone density (T-score ≥ - 1.0), osteopenia (- 2.5 < T-score < - 1.0) and osteoporosis (T-score ≤ - 2.5). The receiver operating characteristic curve (ROC) was drawn to analyze the diagnostic performance of S1 VBQ in distinguishing low BMD. Statistical significance was set at p < 0.05.

RESULTS

A total of 207 patients were included. The S1 VBQ were significantly different between groups (p < 0.001). Interclass correlation coefficient for inter-rater reliability was 0.86 (95% CI 0.78-0.94) and 0.94(95% CI 0.89-0.98) for intra-rater reliability. According to the linear regression analysis, the S1 VBQ has moderate-to-strong correlations with DEXA T-score (r = - 0.48, p < 0.001). The area under the ROC curve indicated a predictive accuracy of 82%. A sensitivity of 77.25% with a specificity of 70% could be achieved for distinguishing low BMD by setting the S1 VBQ cutoff as 2.93.

CONCLUSIONS

The S1 VBQ was a promising tool in distinguishing poor bone quality in patients with lumbar degenerative diseases, especially in cases where the previously reported VBQ method based on L1-L4 was not available. S1 VBQ score could be useful as opportunistic assessment for screening and complementary evaluation to DEXA T-score before surgery.

Combination of vertebral bone quality scores from different magnetic resonance imaging sequences improves prognostic value for the estimation of osteoporosis

BACKGROUND CONTEXT

Recent findings revealed a correlation between vertebral bone quality based on T1-weighted (VBQ_T1) magnetic resonance imaging (MRI) and volumetric bone mass density (vBMD) measured using quantitative computerized tomography. The coherence of VBQ for other MRI sequences, such as T2 or short tau inversion recovery (STIR), has not been examined. The combination of different VBQs has not been studied.

PURPOSE

The aims of the study were to confirm the correlation between VBQ_T1 and vBMD and to examine VBQs from other MRI sequences and their combination with vBMD.

STUDY DESIGN/SETTING

This was a retrospective cross-sectional study.

PATIENT SAMPLE

The sample consisted of patients older than 18 years, who received treatment at a level-one university spine center of the German Spine Society for degenerative or traumatic reasons in 2017-2021.

OUTCOME MEASURES

The outcome measures were the correlation of VBQs from different MRI sequences with vBMD and the association of VBQs with osteopenia/osteoporosis.

METHODS

Patients' VBQ was calculated based on the signal intensities of the vertebral bodies L1-4 in T1-, T2-, and STIR-weighted MRI. The VBQ was standardized according to the signal intensity of the cerebrospinal fluid. The vBMD was determined using data from a calibrated scanner (SOMATOM Definition AS+) and processed with CliniQCT (Mindways Software, Inc., USA). Groups were divided according to vBMD into the following groups: (I) osteoporosis/osteopenia (< 120 mg/m³) and (II) healthy (≥120 mg/m³). An analysis of the correlation between various VBQs and vBMD as well as receiver operating characteristic (ROC) and binary regression analyses were performed for the prediction of osteoporosis/osteopenia.

RESULTS

We included 136 patients (women: 56.6%) in the study (69.7 ± 15.0 years). According to vBMD, 108 patients (79.4%) had osteoporosis/osteopenia. Women were affected significantly more often than men (p = .045) and had significantly higher VBQ_T1 and VBQ_T2 values than men (VBQ_T1: p = .048; VBQ_T2: p = .013). VBQ_T1 and VBQ_T2 values were significantly higher in patients with osteoporosis/osteopenia than in healthy persons (VBQ_T1: p<.001; VBQ_T2: p = .025). VBQ_T1 and VBQ_T2 were significantly negatively correlated with vBMD with a moderate effect size (p<.001), while VBQ_STIR was not significantly correlated with vBMD, although it showed a positive coherence. The combination of different VBQs in terms of VBQ_T1 × VBQ_T2 / VBQ_STIR distinctly increased the effect size of the negative correlation with vBMD compared to VBQ alone. A cutoff value for VBQ_T1 × VBQ_T2 / VBQ_STIR of 2.9179 achieved a sensitivity of 80.0%, a specificity of 75.0%, and an area under the curve (AUC) of 0.775 for the determination of osteoporosis. The mathematical model derived from the binary logistic regression showed an excellent AUC of 0.846.

CONCLUSIONS

This study confirms a significant correlation between VBQ_T1 and vBMD. The combination of VBQs from different MRI sequences enhances the prognostic value of VBQ for the determination of osteoporosis. While safe clinical application of VBQ for the determination of osteoporosis requires further validation, VBQ might offer opportunistic estimation for further diagnostics.

MRI-Based Score for Assessment of Bone Mineral Density in Operative Spine Patients

STUDY DESIGN

Retrospective comparison.

OBJECTIVE

The aim was to determine whether a previously developed magnetic resonance imaging (MRI)-derived bone mineral density (BMD) scoring system can differentiate between healthy and osteoporotic vertebrae and to validate this scoring system against quantitative computed tomography measurements.

SUMMARY OF BACKGROUND DATA

BMD is an important preoperative consideration in spine surgery. Techniques to measure BMD are subject to falsely elevated values in the setting of spondylosis (dual-energy X-ray absorptiometry) or require significant exposure to radiation [quantitative computed tomography (QCT)]. Previous studies have shown that MRI may be utilized to measure bone quality using changes in the bone marrow signal observed on T1-weighted MRIs.

MATERIALS AND METHODS

Retrospective study of patients who underwent operative lumbar procedures at a single tertiary institution between 2016 and 2021 (n=61). Vertebral bone quality (VBQ) scores were measured by dividing the median signal intensities of L1-L4 by the signal intensity of cerebrospinal fluid on noncontrast T1W MRI. Demographic data, comorbidities, VBQ scores, and QCT-derived T scores and BMD of the lumbar spine were compared between healthy ( T score ≥-1; n=21), osteopenic (-2.5 < T score < -1; n=21), and osteoporotic ( T score ≤-2.5; n=19) cohorts using analysis of variance with post hoc Tukey test. Linear regression and receiver operating characteristic curve analyses were performed to assess the predictive value of VBQ scores. Pearson correlation test was used to evaluate the association between VBQ scores and QCT-derived measurements.

RESULTS

VBQ differentiated between healthy and osteoporotic groups ( P =0.009). Receiver operating characteristic curve analysis revealed that a greater VBQ score was associated with presence of osteoporosis (area under the curve=0.754, P =0.006). Cutoff VBQ for osteoporosis was 2.6 (Youden index 0.484; sensitivity: 58%; specificity: 90%). VBQ scores weakly correlated with QCT-derived BMD ( P =0.03, r =-0.27) and T scores ( P =0.04, r =-0.26).

CONCLUSION

This study attempted to further validate a previously developed MRI-based BMD scoring system against QCT-derived measurements. VBQ score was found to be a significant predictor of osteoporosis and could differentiate between healthy and osteoporotic vertebrae.

Disc degeneration contributes to the denser bone in the subendplate but not in the vertebral body in patients with lumbar spinal stenosis or disc herniation

BACKGROUND CONTEXT

It is commonly believed that decreased bone quality would lead to endplate degeneration and arthritic changes in the facet joints, and thus accelerated disc degeneration (DD). However, some more detailed studies of vertebral bone structure have found that bone mineral density (BMD) in the vertebral body is increased rather than decreased in moderate or greater disc degeneration. The relationship between BMD and DD still needs further study. MRI-based vertebral bone quality scores have been shown to be effective in reflecting BMD, rendering a new way to evaluate the changes of vertebral body bone with DD using MRI alone.

PURPOSE

To evaluate MRI-based vertebral bone quality and Pfirrmann grades in patients with lumbar spinal stenosis or disc herniation, and to identify if DD is associated with denser bone around the endplate.

STUDY DESIGN/SETTING

A single-center, retrospective cohort study.

PATIENT SAMPLE

A total of 130 patients with lumbar disc herniation and lumbar spinal stenosis from January 2019 to November 2020 who had a complete dual-energy X-ray absorptiometry scan and noncontrast lumbosacral spine MRI data.

OUTCOME MEASURES

The vertebral bone quality score (VBQ) and sub-endplate bone quality score (EBQ) was calculated as a ratio of the signal intensity of the vertebral bodies and sub-endplate regions to the signal intensity of the cerebrospinal fluid at L3 on the mid-sagittal T1-weighted MRI images, respectively. The Pfirrmann grades of the lumbar discs were assessed as well.

METHODS

The age, gender, body mass index, and T-score of the lumbar spine of the patients were collected. The degeneration grades of the lumbar discs were evaluated according to the Pfirrmann classification. VBQ and EBQ were measured through T1-weighted lumbar MRI. The VBQ and EBQ scores were compared between cranial and caudal sides. The correlation between MRI-based bone quality and DD was calculated. A linear regression model was used to examine the association between DD and adjacent EBQ and VBQ.

RESULTS

This study included 569 lumbar segments from 130 inpatients. Cranial and caudal EBQ decreased with the increase of the Pfirrmann grade. The discs with Pfirrmann grade 5 had significantly lower caudal EBQ than the discs with Pfirrmann grades 2, 3, and 4. In the osteoporosis patients, the Pfirrmann grades negatively correlated both with the cranial EBQ and caudal EBQ. Pfirrmann grade greater than 4 was an independent contributor to the cranial EBQ, whereas greater than 3 was an independent contributor to the caudal EBQ.

CONCLUSIONS

Disc degeneration grades correlated with the EBQ but not with the VBQ. In patients with lumbar spinal stenosis or disc herniation, DD contributes to the denser bone in the sub-endplate, but not in the whole vertebral body.

Vertebral Bone Quality Score Independently Predicts Proximal Junctional Kyphosis and/or Failure After Adult Spinal Deformity Surgery

BACKGROUND

Proximal junctional kyphosis (PJK) and proximal junctional failure (PJF) can be catastrophic complications associated with adult spinal deformity (ASD) surgery. These complications are markedly influenced by osteoporosis, leading to additional vertebral fracture and pedicle screw loosening. The MRI-based vertebral bone quality score (VBQ) is a newly developed tool that can be used to assess bone quality.

OBJECTIVE

To investigate the utility of the VBQ score in predicting PJK and/or PJF (PJF/PJK) after ASD correction.

METHODS

We conducted a retrospective chart review to identify patients age ≥50 years who had received ASD surgery of 5 or more thoracolumbar levels. Demographic, spinopelvic parameters, and procedure-related variables were collected. Each patient's VBQ score was calculated using preoperative T1-weighted MRI. Univariate analysis and multivariate logistic regression were performed to determine potential risk factors of PJK/PJF. Receiver operating characteristic analysis and area-under-the-curve values were generated for prediction of PJK/PJF.

RESULTS

A total of 116 patients were included (mean age, 64.1 ± 6.8 years). Among them, 34 patients (29.3%) developed PJK/PJF. Mean VBQ scores were 3.13 ± 0.46 for patients with PJK/PJF and 2.46 ± 0.49 for patients without, which was significantly different between the 2 groups ( P < .001). On multivariate analysis, VBQ score was the only significant predictor of PJK/PJF (odds ratio = 1.745, 95% CI = 1.558-1.953, P < .001), with a predictive accuracy of 94.3%.

CONCLUSION

In patients undergoing ASD correction, higher VBQ was independently associated with PJK/PJF occurrence. Measurement of VBQ score on preoperative MRI may be a useful adjunct to ASD surgery planning.

Vertebral bone quality score independently predicts cage subsidence following transforaminal lumbar interbody fusion

BACKGROUND CONTEXT

Cage subsidence following transforaminal lumbar interbody fusion (TLIF) has been associated with poor bone quality. Current evidence suggests that the magnetic resonance imaging (MRI)-based vertebral bone quality (VBQ) score correlates with poor bone quality.

PURPOSE

To our knowledge, this is the first study to assess whether the VBQ score can predict the occurrence of postoperative cage subsidence after TLIF surgery.

DESIGN/SETTING

Retrospective single-center cohort.

PATIENT SAMPLE

Patients undergoing single-level TLIF for degenerative spine disease between February 2014 and October 2021.

OUTCOME MEASURES

Extent of subsidence.

METHODS

Demographic, procedure-related, and radiographic data were collected for study patients. VBQ scores were determined from preoperative T1-weighted MRI. Subsidence was defined as ≥2 mm of migration of the cage into the superior or inferior end plate or both. Univariate and multivariate logistic regression were used to determine the correlation between potential risk factors for subsidence and actual subsidence rates.

RESULTS

Subsidence was observed among 42 of the 74 study patients. The mean VBQ scores were 2.9±0.5 for patients with subsidence and 2.5±0.5 for patients without subsidence. The difference among groups was significant (p=.003). On multivariate logistic regression, a higher VBQ score was significantly associated with an increased risk of subsidence (OR=1.5, 95% CI=1.160-1.973, p=.004) and was the only significant independent predictor of subsidence after TLIF.

CONCLUSION

We found that a higher VBQ score was significantly associated with cage subsidence following TLIF. The MRI-VBQ score may be a valuable tool for assisting in identifying patients at risk of cage subsidence following TLIF.

Bone quality in patients with osteoporosis undergoing lumbar fusion surgery: analysis of the MRI-based vertebral bone quality score and the bone microstructure derived from microcomputed tomography

BACKGROUND CONTEXT

Osteoporosis is a risk factor for instrumentation failure in spine surgery. Bone strength is commonly assessed by bone mineral density (BMD) as a surrogate marker. However, BMD represents only a portion of bone strength and does not capture the qualitative dimensions of bone. Recently, the magnetic resonance imaging (MRI)-based vertebral bone quality (VBQ) score was introduced as a novel marker of bone quality. However, it is still unclear if the VBQ score correlates with in-vivo bone microstructure.

PURPOSE

The aims of the study were (1) to demonstrate differences in MRI-based (VBQ) and in-vivo (microcomputed tomography; μCT) bone quality between osteopenic/osteoporotic and normal bone, (2) to show the correlation between VBQ, bone microstructure and volumetric BMD (vBMD), and (3) to determine the predictive value of the VBQ score for the prevalence of osteopenia/osteoporosis.

STUDY DESIGN/SETTING

Retrospective cross-sectional study.

PATIENT SAMPLE

267 patients who underwent posterior lumbar fusion surgery from 2014 to 2021 at a single academic institution. Bone biopsies were harvested intraoperatively in 118 patients.

OUTCOME MEASURES

VBMD, VBQ score, and bone microstructure parameters derived from μCT.

METHODS

Quantitative computed tomography (QCT) measurements were performed at the lumbar spine and the L1/L2 average was used to categorize patients with a vBMD ≤120mg/cm³ as osteopenic/osteoporotic. The VBQ score was determined by dividing the median signal intensity of the L1-L4 vertebrae by the signal intensity of the cerebrospinal fluid using sagittal T1-weighted MRI scans. Intraoperative bone biopsies from the posterior superior iliac spine were obtained and evaluated with μCT. VBQ scores and μCT parameters were compared between the normal and the osteopenic/osteoporotic group. Correlations between VBQ score, μCT parameters and vBMD were assessed with Spearman's correlation (ρ). Receiver operating characteristic (ROC) analysis was performed to determine the VBQ score as a predictor for osteopenia/osteoporosis. Multiple linear regression analysis with vBMD L1/L2 as outcome was used to identify independent predictors from VBQ, μCT parameters and demographics.

RESULTS

267 patients (55.8% female, age 63.3 years, BMI 29.7 kg/m²; n=118 with bone biopsy) with a prevalence of osteopenia/osteoporosis of 65.2% were analyzed. In the osteopenic/osteoporotic group the VBQ score, structured model index (SMI), and trabecular separation (Tb.Sp) were significantly higher, whereas bone volume fraction (BV/TV), connectivity density (Conn.D) and trabecular number (Tb.N) were significantly lower. There were significant correlations between VBQ and μCT parameters ranging from ρ=-.387 to ρ=0.314 as well as between vBMD and μCT parameters ranging from ρ=-.425 to ρ=.421, and vBMD and VBQ (ρ=-.300, p<.001). ROC analysis discriminated osteopenia/osteoporosis with a sensitivity of 84.7% and a specificity of 40.6% at a VBQ score threshold value of 2.18. Age, BV/TV and trabecular thickness (Tb.Th), but not VBQ, were significant independent predictors for vBMD (corrected R²=0.434).

CONCLUSIONS

This study demonstrated for the first time that the VBQ score is associated with trabecular microstructure determined by μCT. The bone microstructure and VBQ score were significantly different in patients with impaired vBMD. However, the ability to predict osteopenia/osteoporosis with the VBQ score was moderate. The VBQ score appears to reflect additional bone quality characteristics and might have a complementary role to vBMD. This enhances our understanding of the biological background of the radiographic VBQ score and might be a take-off point to evaluate the clinical utility of it as non-invasive screening tool for bone quality.

Risk assessment tools for osteoporosis and fractures in 2022

Osteoporosis is one of the frequently encountered non-communicable diseases in the world today. Several hundred million people have osteoporosis, with many more at risk. The clinical feature is a fragility fracture (FF), which results in major reductions in the quality and quantity of life, coupled with a huge financial burden. In recognition of the growing importance, the World Health Organisation established a working group 30 years ago tasked with providing a comprehensive report to understand and assess the risk of osteoporosis in postmenopausal women. Dual-energy X-ray absorptiometry (DXA) is the most widely endorsed technology for assessing the risk of fracture or diagnosing osteoporosis before a fracture occurs, but others are available. In clinical practice, important distinctions are essential to optimise the use of risk assessments. Traditional tools lack specificity and were designed for populations to identify groups at higher risk using a 'one-size-fits-all' approach. Much has changed, though the purpose of risk assessment tools remains the same. In 2022, many tools are available to aid the identification of those most at risk, either likely to have osteoporosis or suffer the clinical consequence. Modern technology, enhanced imaging, proteomics, machine learning, artificial intelligence, and big data science will greatly advance a more personalised risk assessment into the future. Clinicians today need to understand not only which tool is most effective and efficient for use in their practice, but also which tool to use for which patient and for what purpose. A greater understanding of the process of risk assessment, deciding who should be screened, and how to assess fracture risk and prognosis in older men and women more comprehensively will greatly reduce the burden of osteoporosis for patients, society, and healthcare systems worldwide. In this paper, we review the current status of risk assessment, screening and best practice for osteoporosis, summarise areas of uncertainty, and make some suggestions for future developments, including a more personalised approach for individuals.