Bracing versus balloon kyphoplasty for acute osteoporotic vertebral fractures with poor prognostic radiological factors: a propensity score-matched comparison.

Abstract

Among acute osteoporotic vertebral fractures with poor prognostic MRI findings, early balloon kyphoplasty did not improve 12-week pain compared with bracing after propensity score matching. However, kyphoplasty better preserved vertebral body height, suggesting that its main early benefit in this subgroup may be structural rather than analgesic. The optimal management for acute osteoporotic vertebral fractures (OVFs) with radiological signs suggesting a poor prognosis remains controversial. This study aimed to compare 12-week clinical and radiographic outcomes of early balloon kyphoplasty (BKP) versus brace treatment in acute OVFs with poor prognostic magnetic resonance imaging (MRI) findings. We compared a prospective BKP cohort (n = 82) with historical brace-treated controls (n = 62) from a prior randomized trial. Eligible patients were aged ≥ 65 years, had acute OVFs with fluid or diffuse low-intensity signal on T2-weighted MRI, and had back pain visual analog scale (VAS) scores ≥ 4/10. The primary outcome was 12-week back pain VAS; the secondary outcome was anterior vertebral body compression percentage (AVBCP). The primary analysis involved a direct comparison of these 12-week post-treatment measurements between the BKP and brace groups. One-to-one propensity score matching was performed using age, sex, and the anatomical location of the fracture (thoracic, thoracolumbar junction, or lumbar). Back pain improved significantly from baseline to 12 weeks within both the BKP group (from 73.6 ± 27.3 to 21.8 ± 19.5, p < 0.0001) and the brace group (from 74.9 ± 23.9 to 30.2 ± 23.3, p < 0.0001). In the crude analysis, BKP was associated with lower VAS scores (21.8 ± 19.5 vs. 30.2 ± 23.3, p = 0.047) and higher AVBCP (67.4 ± 12.3% vs. 49.4 ± 14.1%, p < 0.0001) at 12 weeks. After propensity score matching, 42 pairs were analyzed; no significant between-group difference in 12-week VAS was observed (23.5 ± 20.7 in the BKP group vs. 27.2 ± 21.0 in the brace group, p = 0.45), whereas AVBCP remained significantly higher in the BKP group (66.4 ± 13.3% vs. 48.6 ± 14.7%, p < 0.0001). In acute OVFs with poor prognostic radiological factors, early BKP did not provide superior 12-week pain relief compared with bracing after adjustment for baseline confounders. However, BKP was more effective in limiting early vertebral body collapse.