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

Risk factors influencing cage retropulsion following lumbar interbody fusion in treating degenerative lumbar diseases: A comprehensive systematic review and meta-analysis

BACKGROUND

Degenerative lumbar diseases (DLDs) often have significant impacts on patients' quality of life, particularly when cage retropulsion (CR) occurs following lumbar interbody fusion (LIF). In this study, we conducted a meta-analysis to assess the risk factors associated with CR after LIF.

METHODS

We retrieved literatures analyzing the risk factors associated with CR following LIF from seven databases. We examined baseline characteristics, diagnosis, comorbidity, fusion level, surgical status, imaging assessment, and cage status to identify potential risk factors.

RESULTS

Sixteen studies involving 8059 patients (251 in the CR group and 7808 in the Non-CR group) were included in the final analysis. The incidence of CR was 3.15 %. Results revealed that older age (mean difference [MD]: 2.35 [0.44, 4.26]), more fusion levels (MD: 0.64 [0.03, 1.25]), comorbidity-osteoarthritis (risk ratio [RR]: 2.02 [1.37, 2.98]), comorbidity-heart disease (RR: 2.95 [1.21, 7.21]), comorbidity-existing vertebral fracture (RR: 5.12 [2.52, 10.39]), endplate injury (RR: 2.93 [1.71, 5.02]), screw loosening (RR: 6.03 [1.90, 19.12]), pear-shaped disc (PSD, RR: 3.14 [1.46, 6.74]), greater mean disc height (MDH, MD: 1.65 [0.58, 2.72]), larger cobb angle (MD: 0.68 [0.10, 1.27] degrees), larger cage height (MD: 0.31 [0.01, 0.61]), and cage type-carbon (RR: 1.62 [1.16, 2.27]) were identified as risk factors for CR following LIF. The incidence of CR decreased with an increase in fusion level.

CONCLUSIONS

Older age, endplate injury, PSD, and nine other factors are identified as risk factors for CR following LIF. Patients with these factors should undergo close monitoring during follow-up to prevent serious complications, such as significant cage displacement.

MRI-based endplate bone quality scores outperform vertebral bone quality scores in predicting adjacent segment disease following transforaminal lumbar interbody fusion

PURPOSE

This study aims to (1) evaluate whether the endplate bone quality (EBQ) scores can independently predict adjacent segment disease (ASD); and (2) judge the predictive value of EBQ compared to vertebral bone quality (VBQ) for ASD after single-level transforaminal lumbar interbody fusion (TLIF).

METHODS

A single-center retrospective analysis was conducted of patients undergoing single-level TLIF for degenerative spinal disease from 2014 to 2020. Demographic, surgery, and radiographic data were collected. Logistic regression was used to identify independent risk factors for ASD. Furthermore, a receiver operating curve (ROC) analysis was conducted to evaluate the predictive efficacy of the EBQ score and VBQ score.

RESULTS

The rate of ASD was 16.4% at a minimum 24-month follow-up. Significant risk factors for ASD were higher VBQ score (OR = 3.418, 95%CI: 1.297-9.008, P = 0.013), higher EBQ score (OR = 2.469, 95%CI: 1.085-5.621, P = 0.031), and higher adjacent segment Pfirrmann grade (OR = 2.866, 95%CI: 1.765-4.653, P<0.001). The diagnostic accuracy of VBQ and EBQ for distinguishing ASD were 0.806 (95%CI: 0.728-0.883) and 0.835 (95%CI: 0.757-0.912). The optimal threshold of VBQ scores was 2.926 (sensitivity: 90.6%, specificity: 62.0%) and of EBQ was 3.511 (sensitivity: 90.6%, specificity: 71.8%).

CONCLUSION

Higher VBQ and EBQ scores are both independent risk factors of ASD after single-segment TLIF surgery, and EBQ scores perform better in predicting ASD. When EBQ > 3.511, there is a considerable risk of ASD.

Comparative analysis of MRI-based VBQ and EBQ score for predicting cage subsidence in PILF surgery

BACKGROUND CONTEXT

As lumbar degenerative diseases become more prevalent in an aging population, there is an increasing demand for surgical interventions, such as posterior lumbar interbody fusion (PLIF). However, cage subsidence (CS), observed in 23.9-54% of cases postoperatively, remains a significant complication. Several factors, including age, bone quality, and endplate damage, contribute to the risk of CS, with bone quality being among the most critical determinants. Although DEXA and QCT are widely employed to assess bone density, their routine use in preoperative evaluations is restricted by cost considerations and radiation exposure. Recent studies suggest that MRI-based vertebral body quality (VBQ) and endplate bone quality (EBQ) score offer a viable, non-invasive alternative for evaluating bone quality; however, there is limited research comparing their predictive value for CS.

METHODS

In this retrospective study, 165 patients undergoing single-level PLIF surgery were included. MRI-based VBQ and EBQ score were calculated using T1-weighted images, and preoperative QCT was employed as a clinical standard. Cage subsidence was assessed based on postoperative imaging at 12-month follow-up. Statistical analyses, including t-tests, chi-square tests, and ROC curve analyses, were used to evaluate the predictive accuracy of VBQ and EBQ for CS.

RESULTS

The study's findings demonstrated that both VBQ and EBQ scores were significantly correlated with QCT measurements, thereby validating their utility as indicators of bone quality. ROC analysis revealed that VBQ had superior predictive value for CS (AUC = 0.814) compared to EBQ (AUC = 0.719), with both scores demonstrating significant clinical utility in identifying patients at risk for CS. Notably, VBQ exhibited a stronger correlation with preoperative clinical outcomes compared to EBQ, underscoring its greater reliability as a predictor.

CONCLUSIONS

This study highlights the effectiveness of MRI-based VBQ and EBQ score as practical, non-invasive tools for assessing bone quality preoperatively, with VBQ demonstrating superior predictive performance for CS risk. The findings underscore the potential of integrating these MRI-based assessments into routine preoperative planning to improve patient outcomes and minimize complications associated with PLIF surgery.

Exploring the impact of body mass index on the accuracy of vertebral bone quality in determining bone mineral density in patients undergoing lumbar fusion surgery

OBJECTIVE

To investigate whether body mass index (BMI) affects the accuracy of vertebral bone quality (VBQ) in determining bone mineral density (BMD) in patients undergoing lumbar fusion surgery.

METHODS

In this retrospective study, patients with preoperative noncontrast T1-weighted MRI were included. Restricted Cubic Spline (RCS) was employed to explore the nonlinear relationship between BMI and VBQ. Then patients were stratified according to the threshold of BMI. Pearson correlation analysis and linear regression were used to analyze the correlation between VBQ and the BMD in different groups. Receiver operating characteristic (ROC) analysis to calculate the area under the curve (AUC) was used to assess diagnostic efficacy according to BMI.

RESULTS

A total of 328 patients (201 female and 127 male patients) with a mean age of 68.3 ± 3.3 years were included in the study. Significant nonlinear relationship was observed given the results of RCS. In patients with BMI < 23.8 kg/m2, the correlation coefficient between VBQ and the lowest BMD was - 0.32 and significant distribution difference of VBQ score was observed between osteoporosis and normal as well as osteopenia subgroups. However, in patients with BMI ≥ 23.8 kg/m2, the correlation coefficient between VBQ and the lowest BMD was - 0.39 and significant distribution difference of VBQ score was observed in all three subgroups. In addition, the ROC analysis revealed that the predictive performance in determining low BMD was superior in patients with BMI ≥ 23.8 kg/m2 (AUC 0.80 vs. AUC 0.66, p = 0.034).

CONCLUSIONS

In this study, significant nonlinear relationship between BMI and VBQ was observed. Compared with patients with BMI < 23.8 kg/m2, VBQ has better discrimination between higher BMI (≥ 23.8 kg/m2) patients with low BMD and those with normal bone density.

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.

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.