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.