Recompression of Augmented Vertebrae after Balloon Kyphoplasty Is a Risk of Adjacent Vertebral Fracture.

Introduction: This study aimed to identify factors associated with adjacent vertebral fracture (AVF) incidence after balloon kyphoplasty (BKP). Methods: To perform the analyses, 133 vertebrae of 128 patients who underwent BKP for osteoporotic vertebral compression fracture were retrospectively investigated. According to the presence of AVF throughout a 1-year period following BKP, patients were divided into AVF (n = 22) and non-AVF (n = 111) groups. The groups were compared with respect to pre- and postoperative parameters, including the incidence of recompression of augmented vertebrae (RAV). RAV was defined as a decrease in anterior vertebral body height of at least 5 mm within the 3 months that followed BKP. To identify factors associated with AVF incidence, univariate and multivariate analyses were performed. Results: The univariate analysis revealed that the AVF group had a lower cement augmentation ratio, greater preoperative wedge angle, lower preoperative vertebral body height, lower postoperative vertebral body height 3 months post-BKP, and a greater change in vertebral body height and rate of RAV than the non-AVF group. Multivariate analysis revealed that low preoperative vertebral body height and RAV occurrence were associated with AVF incidence. Conclusions: To the best of our knowledge, this study is the first to indicate that RAV is a risk factor for AVF. Study findings indicate that the incidence of AVF can be decreased if RAV development is avoided.