Study design: A multicenter, prospective, single-arm, intervention study.
Objective: The aim of this study was to investigate efficacy of balloon kyphoplasty (BKP) for acute osteoporotic vertebral fractures (OVFs) in patients with poor prognostic factors.
Summary of background data: The indications for BKP remain unclear. Characteristic magnetic resonance imaging (MRI) findings (high-intensity or diffuse low-intensity area in fractured vertebrae on T2-weighted images) were reportedly predictive of delayed union.
Methods: This study enrolled 106 patients with poor prognostic MRI findings who underwent BKP within 2 months after injury, and 116 controls with acute OVFs and the same poor prognostic factors who underwent conservative treatment. Patients were propensity score matched in a logistic regression model adjusted for age, sex, number of baseline old fractures, and fracture level. The primary outcome was reduction in activities of daily living (ADLs) at 6 months after fracture, and the secondary outcomes were improvement in short-form (SF)-36 subscales, back pain visual analog scale (VAS) score, and vertebral body deformity.
Results: A decrease in ADLs occurred in 5.6% of patients in the BKP group and 25.6% of patients in the conservative treatment group (P < 0.001). The SF-36 vitality subscale score improved by 26.9 ± 25.9 points in the BKP group and 14.5 ± 29.4 points in the control group (P = 0.03). The VAS pain score improved by 43.4 ± 34.4 in the BKP group and 52.2 ± 29.8 in the control group (P = 0.44). The vertebral body wedge angle improved by 5.5 ± 6.2° in the BKP group and -6.3 ± 5.0° in the control group (P < 0.0001). The percent vertebral body height improved by 15.2 ± 19.2% in the BKP group and -20.6 ± 14.2% in the control group (P < 0.0001).
Conclusion: ADLs, quality of life, and vertebral deformity showed greater improvement with BKP intervention for acute OVF with poor prognostic factors than with conservative treatment at 6 months after injury. Our treatment strategy uses BKP intervention according to the presence or absence of poor prognostic MRI findings.
Level of evidence: 4.