Cement augmentation techniques in traumatic thoracolumbar spine fractures

Study Design. Review of human cadaveric and in vivo animal studies and clinical trial. Objective. To develop less invasive surgical techniques for reconstruction of the anterior column in thoracolumbar fractures. Summary of Background Data. Persistent central endplate depression can cause anterior column insufficiency after posterior surgery for traumatic thoracolumbar fractures. Reduction of the central endplate followed by intravertebral cement augmentation could restore weight-bearing capacity. Materials and Methods. In human cadaveric burst fracture models, balloon-assisted end-plate reduction (BAER) and vertebroplasty techniques have been investigated in terms of their safety and biomechanical properties. The histologic properties of different cement polymers were studied in an animal vertebral body and endplate defect model. In addition, the clinical outcome of percutaneous cement augmentation in the setting of a burst fracture examining the BAER technique and vertebroplasty with adjunctive posterior pedicle screw fixation is reviewed. Results. These techniques have proven to be safe and effective, although cement leakage outside the confines of the vertebral body may occur. Calcium phosphate cements are preferable over methylmethacrylate because of their in vivo histologic properties. Using the BAER technique and posterior pedicular fixation, anterior vertebral height restoration is possible. Following balloon removal, some loss of fracture height restoration is observed, Further loss of vertebral height reduction was not observed following cement curing clinically. Conclusions. These studies show that less invasive anterior vertebral reconstruction using percutaneous cement augmentation techniques is feasible following traumatic vertebral fractures.