Presence or absence of adjacent vertebral fractures has no effect on long-term global alignment and quality of life in patients with osteoporotic vertebral fractures treated with balloon kyphoplasty

Background: Global sagittal malalignment after osteoporotic vertebral fracture is correlated with decreased quality of life. Balloon kyphoplasty promotes short-term global alignment, but long-term correction is difficult in patients with such fractures. Adjacent vertebral fracture is one of the major complications of balloon kyphoplasty. We investigated the correlation of the incidence of adjacent vertebral fracture with the loss of global alignment correction after balloon kyphoplasty. Methods: Forty patients were enrolled in this retrospective study. Adjacent vertebral fracture occurred in 17 patients. Sagittal vertical axis, the angle between the two vertebrae above and below the balloon kyphoplasty site (local alignment angle), and the vertebral kyphotic angle at the kyphoplasty site were measured preand post-operatively. Clinical results were assessed. Results: There were no significant differences between the sagittal vertical axis before and after balloon kyphoplasty in groups with (+) or without (-) adjacent vertebral fracture. Local alignment angles decreased soon after balloon kyphoplasty, but increased during follow-up in both groups. Vertebral kyphotic angles decreased significantly soon after balloon kyphoplasty in both groups; although this increased significantly in the adjacent vertebral fracture (-) group, but not in the adjacent vertebral fracture (+) group, during follow-up. Correction loss of alignment was found in both adjacent vertebral fracture (+) and (-) groups, attributed to adjacent vertebral fracture in the former and re-collapse of the balloon kyphoplasty site in the latter. No significant differences in clinical results were observed between the groups, although these were strongly correlated with sagittal vertical axis before balloon kyphoplasty. Conclusions: The adjacent vertebral fracture (+) and (-) groups exhibited similar correction loss of alignment and improved quality of life. The presence or absence of adjacent vertebral fractures had no effect on long-term global alignment and patient quality of life. (C) 2019 The Japanese Orthopaedic Association. Published by Elsevier B.V. All rights reserved.