Kyphoplasty Restores the Global Sagittal Balance of the Spine Independently from Pain Reduction

Kyphoplasty is the standard surgical treatment of vertebral compression fractures. We aimed to clarify the influence of kyphoplasty on the sagittal profile as well as the relation between posture improvement and pain relief. For this purpose, we evaluated various radiological parameters of the sagittal profile on whole spine standing radiographs of 73 Patients with a single vertebral fracture treated by kyphoplasty. The key outcome was the postoperative change of the sagittal vertical axis (SVA). Additionally, clinical parameters including pain scores on visual analogue scale (VAS) and use of analgesics were obtained from medical records. Pre- and postoperative radiological as well as clinical parameters were compared. Additionally, the correlation between changes of SVA and changes of local kyphotic angle (LKA) or VAS was examined. The clinical parameters as well as various radiographic parameters (SVA, LKA, Gardner, Cobb) improved significantly postoperatively. The improvement of SVA correlated significantly with the correction of the LKA but not with postoperative pain relief. We conclude that kyphoplasty helps to restore the global sagittal balance of the spine after vertebral fractures. The correction of the sagittal profile seems to depend on the correction of the local kyphotic angle but does not correlate with postoperative pain relief.