Predictive Utility of the Vertebral Bone Quality (VBQ) Score for Spine Surgery Complications: A Systematic Review

Introduction: Low bone mineral density (BMD) increases the risk of spine surgery complications, including pedicle screw loosening (PSL), cage subsidence (CS), adjacent segment disease (ASD), proximal and distal junctional kyphosis/failure (PJK/PJF, DJK/DFJ), recurrent vertebral fracture, and reoperation. Dual-energy X-ray absorptiometry (DEXA) and computed tomography (CT) are established BMD-assessment tools correlating with postoperative outcomes. However, cost, inconvenience, radiation exposure, and pathology limit preoperative utility. Derived from magnetic resonance imaging (MRI), the vertebral bone quality (VBQ) score has emerged as a safe, convenient alternative. Recent literature reporting the VBQ’s predictive capacity for postoperative complications warrants a comprehensive, systematic review to inform clinical use.

Methods: We systematically reviewed (PROSPERO: CRD42024542755) literature reporting the VBQ’s predictive capacity for postoperative complications. We characterize VBQ applications across methods, demographics, and outcomes.

Results: We included 27 studies (4,068 patients, 60.6% female, mean age 58.5 years). 17 used the traditional VBQ (L1-L4/L3); alternatives included C3-C6/C2 (5), C3-C6/C5 (1), L1-L5/L3 (1), L4-L5/L3 (1), and S1/L3 (3). The VBQ significantly predicted PSL (thresholds 2.9-3.175, AUCs 0.72-0.77, ORs 1.02-5.778), CS (thresholds 3.28-4.10, AUCs 0.61-0.99, ORs 0.800-23.158), ASD (thresholds 2.91-2.95, AUCs 0.934-0,963, ORs 1.509-1.601), PJK/PJF (thresholds 2.715-3.205, AUCs 0.721-0.943, ORs 1.745-26.49), DJK/DJF (threshold 2.66, AUC 0.935, OR 1.46), refracture (combined T1T2W VBQ nomorgram threshold -0.73, and ratio of adjacent to injured VBQ < 1.4, AUCs 0.753-0.838, ORs 0.32-2.239), and reoperation (threshold >3, AUCs 0.702-0.856, ORs 1.569-2.096).

Conclusion : The VBQ offers a safe opportunistic measure to predict complications after spine surgery. Methodological heterogeneity limits guideline development. Future research with consistent VBQ methodology is necessary.