The ANVCFV Score System:Assessment For The Probability Of New Vertebral Compression Fractures After Percutaneous Vertebroplasty In Patients With Vertebral Compression Fractures

Purpose We aim to establish an objective risk score system to assess the possibility of new vertebral fractures in patients with vertebral compression fractures (VCFs) undergoing Percutaneous Vertebroplasty (PVP).Materials and Methods Ethical review committees’ approval were obtained. Patients with VCFs who underwent their first PVP between January,2007 and December,2013 at Hospital A (training cohort) and Hospital B (validation cohort) were included. In training cohort, the independent risk factors for new VCFs after PVP, identified by multivariate stepwise backward Cox regression analysis from the risk factors selected by univariate analysis and Harrell’s C-statistics, were used to develop the score system (ANVCFV:assessment for new VCFs after percutaneous vertebroplasty) to predict the probability of new VCFs.Results 397 patients (training cohort:n=241; validation cohort:n=156) were included in this study. In training cohort, the ANVCFV score was developed based on five independent risk factors for the new VCFs after PVP, including lower CT values, preexisting old VCFs, intradiscal cement leakage, more than one vertebra treated, and superior or inferior marginal cement distribution in the vertebra. The patients were distinctly divided into two groups by the ANVCFV score of-1.5-8.5 points vs>8.5 points in the probability of new VCFs (median fracture-free time:1846 vs.732 days; P<0.001) in training cohort and the accuracy of this score system was 77.4%, while 85.3% in validation cohort.Conclusion Patients who underwent their first PVP with an ANVCFV score>8.5 points may have a greater chance of suffering from new VCFs.