Does balloon kyphoplasty improve the global spinal alignment in osteoporotic vertebral fracture?

Purpose Balloon kyphoplasty (BKP) has been a well-accepted procedure in the treatment of osteoporotic vertebral compression fracture (OVCF), whereas it remains unclear whether or not this procedure has an impact on the global spinal alignment. The purpose of this study is to evaluate the effect of BKP on the global spinal alignment in OVCF. Methods Fifty-six consecutive patients who had undergone BKP for symptomatic OVCF were retrospectively reviewed with a mean follow-up of 32 months. They were seven males and 49 females with a mean age of 75 years. Radiographic assessment was performed using upright whole spine radiographs. The parameters included vertebral kyphosis, mid-vertebral body height and global sagittal spinal alignment (C7 plumb line deviation). Clinical outcomes were evaluated using visual analog scale of back pain. Results Fifty-one of 56 patients (91.1 %) achieved immediate pain relief. Vertebral kyphosis significantly decreased from 18 to 14 degrees, but 43 patients (76.8 %) still had more than 10 degrees of local kyphosis. Subsequent vertebral compression fractures were observed in seven patients (12.5 %). Anterior deviation of a C7 plumb line (C7PL) was 3.1 cm pre-operatively, 3.1 cm postoperatively, and significantly increased to 5.9 cm at the final follow-up. Consistent results were obtained in those with pre-operative sagittal imbalance (> 5 cm anterior deviation of C7PL) and with pre-existing OVCFs. Conclusions BKP contributed to immediate pain relief, but did not improve the global sagittal spinal alignment after OVCF. This procedure should be solely indicated for painful OVCF or non-union, and could not be expected to restore the global sagittal alignment.