Balloon Vertebroplasty with Calcium Phosphate Cement Augmentation for Direct Restoration of Traumatic Thoracolumbar Vertebral Fractures

Study Design. A human cadaveric model was used to evaluate balloon vertebroplasty in traumatic vertebral fractures. Objectives. To assess the feasibility and safety of balloon vertebroplasty followed by calcium phosphate cement augmentation to prevent recurrent kyphosis. Summary of Background Data. Failure after short-segment pedicle-screw fixation for the treatment of vertebral fractures is probably caused by a redistribution of disc material through the fractured endplate into the vertebral body, causing a decrease in anterior column support. This lack of support can give rise to instrument breakage and recurrent kyphosis after removal of the instrumentation. Restoration of the endplate morphology could prevent these events. Methods. Twenty-three traumatic fractures of thoracolumbar vertebrae were created. All fractures were distracted and fixated with short-segment pedicle screws and rods. Transpedicularly introduced inflatable bone tamps and subsequent injection of calcium phosphate cement were used to restore the endplates. Quantitative analyses of magnetic resonance images obtained at three time points were used to evaluate the morphology of the vertebral body and disc-space. After slicing all specimens, macroscopical examination was performed to detect leakage of cement or bone displacement in undesired directions. Results. No technical problems were encountered during the study. The balloon vertebroplasty resulted in a significant (P = 0.0014) decrease of cranial endplate impression. No cement leakage or undesired bone displacement could be detected radiologically or macroscopically. Conclusions. The present study suggests that balloon vertebroplasty may be a safe and feasible procedure for the restoration of traumatic thoracolumbar vertebral fractures.