Background: Percutaneous vertebroplasty (PVP) is widely used for the treatment of painful
vertebral compression fractures (VCFs). However, new VCFs occur frequently after PVP.
Objectives: We aim to establish an objective risk score system to assess the possibility of new
vertebral fractures in patients with VCFs undergoing PVP.
Study Design: This study was a retrospective study, and it was approved by the Institutional
Review Board of our 2 institutions.
Setting: This study consists of patients from 2 large academic centers.
Methods: Patients with VCFs who underwent their first PVP and met the inclusion criteria
between January 2007 and December 2013 at Hospital A (training cohort) and Hospital B
(validation cohort) were included. In the training cohort, the independent risk factors for new
VCFs after PVP were identified by multivariate stepwise backward Cox regression analysis from
the risk factors selected by univariate analysis and Harrell’s C-statistics and used to develop the
score system (assessment for new VCFs after PVP [ANVCFV]) to predict the probability of new
VCFs.
Results: In total, 397 patients (training cohort: n = 241; validation cohort: n = 156) were
included in this study. In the training cohort, the ANVCFV score was developed based on 5
independent risk factors for the new VCFs after PVP, including lower computed tomography
(CT) values, pre-existing old VCFs, intradiscal cement leakage, more than one vertebra treated,
and superior or inferior marginal cement distribution in the vertebra. The patients were divided
into 2 groups by the ANVCFV score of -1.5 to 8.5 vs. > 8.5 points in the probability of new VCFs
(median fracture-free time: 1846 vs. 732 days; P < 0.001) in the training cohort. The accuracy
of this score system was 77.4% for the training cohort and 85.3% for the validation cohort.
Limitations: The main limitations of this study are that it is a retrospective study and that
there is a significant difference of the treated vertebrae of PVP per session between the 2
cohorts.
Conclusion: Patients who underwent their first PVP with an ANVCFV score > 8.5 points may
exhibit an increased chance of suffering from new VCFs.
Key words: Vertebral compression fracture, percutaneous vertebroplasty, newly developed,
risk factors, risk score system, Cox regression model, accuracy, validation
Risk factors for thoracolumbar pain following percutaneous vertebroplasty for osteoporotic vertebral compression fractures
