Clinical, Radiographic, and Morphometric Risk Factors for Adjacent and Remote Vertebral Compression Fractures Over a Minimum Follow-up of 4 Years After Percutaneous Vertebroplasty for Osteoporotic Vertebral Compression Fractures: Novel Three-dimensional Voxel-Based Morphometric Analysis
OBJECTIVE: This study aimed to analyze the risk factors for secondary new vertebral compression fractures (SNVCFs) after percutaneous vertebroplasty (PVP) for osteoporotic vertebral compression fractures. METHODS: We evaluated the association of SNVCFs (adjacent vertebral compression fractures [AVCFs] and remote vertebral compression fractures) with clinical, radiographic, and PVP procedure-related morphologic parameters based on the data collected from 402 patients over a minimum follow-up of 4 years after PVP. Procedure-related morphologic parameters were assessed using a three-dimensional voxel-based analysis. Univariate and multivariate regression analyses were conducted. RESULTS: On univariate analysis, bone mineral density (BMD), preoperative compression ratio, preoperative sagittal index (SI), and intradiscal bone cement leakage were significantly associated with SNVCF and AVCF (P < 0.05), whereas only BMD and preoperative SI were significantly associated with remote vertebral compression fracture (P < 0.05). A large ratio of bone cement volume to vertebral body volume and skewed bone cement distribution along the inferior-to-superior axis were especially significant risk factors for AVCF (P = 0.027 and P = 0.029, respectively). On multivariate analysis, BMD was significantly associated with SNVCF (P = 0.041), whereas upper adjacent intradiscal bone cement leakage was significantly associated with AVCF (P = 0.003). CONCLUSIONS: Low BMD, high preoperative compression ratio, and high preoperative SI may be predictive factors for SNVCFs. In particular, to prevent AVCF, the injected bone cement should be distributed both evenly and symmetrically along the inferior-to-superior axis and the relative bone cement volume should not be excessive. Bone cement should be injected carefully to avoid upper adjacent intradiscal leakage. Prompt BMD correction is important to prevent SNVCF.