Risk Factors for Cement Loosening after Vertebroplasty for Osteoporotic Vertebral Fracture with Intravertebral Cleft: A Retrospective Analysis

STUDY DESIGN: Retrospective case-control study. PURPOSE: To evaluate the primary outcomes and radiographic results of percutaneous vertebroplasty (PVP) in patients with singlelevel osteoporotic vertebral fracture (OVF) with intravertebral cleft (IVC) to identify the risk factors for cement loosening after PVP. OVERVIEW OF LITERATURE: PVP is a widely accepted method for managing painful OVF; however, cement loosening occasionally occurs with poor outcomes. METHODS: This retrospective study involved 195 patients treated with PVP for single-level OVF with IVC. Six months thereafter, the primary outcomes were evaluated using the Visual Analog Scale (VAS) for back pain and the modified Oswestry Disability Index. Computed tomography was conducted to detect cement loosening. Possible risk factors, such as age, sex, wedging angle, intravertebral instability, Parkinson’s disease, spinous process fracture, ankylosing spinal hyperostosis, split vertebrae, and adjacent intervertebral vacuum, were assessed. RESULTS: Forty-nine patients (25%) experienced cement loosening 6 months after PVP. The mean VAS scores were significantly higher in patients with cement loosening than in those without (50 vs. 26 mm, respectively; p <0.01). Cement loosening was closely associated with intravertebral instability (odds ratio [OR], 1.20; 95% confidence interval [CI], 1.04–1.40; p =0.015), Parkinson’s disease (OR, 54.31; 95% CI, 4.47–659.53; p =0.002), spinous process fracture (OR, 7.11; 95% CI, 1.65–30.60; p =0.009), and split vertebrae (OR, 11.59; 95% CI, 1.64–82.02; p =0.014). CONCLUSIONS: Patients with cement loosening experienced worse back pain than those without cement loosening. The important risk factors that influenced cement loosening after PVP were high intravertebral instability, Parkinson’s disease, spinous process fracture, and split vertebrae.