Height Restoration and Preservation in Osteoporotic Vertebral Compression Fractures A Biomechanical Analysis of Standard Balloon Kyphoplasty Versus Radiofrequency Kyphoplasty in a Cadaveric Model

Study Design: Biomechanical cadaver study. Objective: The aim of the present study was to evaluate 2 different methods with respect to height restoration and preservation in a cadaver model under cyclic loading. Summary of Background Data: Standard balloon kyphoplasty (BKP) represents a well-established treatment opportunity for osteoporotic vertebral compression fractures. BKP was developed to restore vertebral height and improve sagittal alignment. Its use has grown significantly over the last 2 decades. In contrast, distinct biomechanical data are missing. Within the last few years, several alternative techniques with regard to height restoration have emerged, such as radiofrequency kyphoplasty (RFK). Methods: Twenty-five vertebral bodies of 2 female cadavers with secured osteoporosis were examined. Standardized vertebral wedge compression fractures were created. Afterward, 2 groups were randomly assigned: 12 vertebral bodies were treated with BKP and 13 vertebral bodies by RFK under a preload of 100 N. Then the vertebral bodies underwent cyclic loading (100,000 cycles, 100 to 600 N, 5 Hz). Anterior, central, and posterior vertebral body heights were evaluated by CT scans. Results: Anterior height was reduced after fracture 6.3mm (SD 3) for the BKP group and 7.2mm (SD 3) in the RFK group (P > 0.1). After treatment, the difference in the initial anterior height was 4.5mm (SD 2) for the BKP group and 4.7mm (SD 3) for the RFK group (P > 0.1). After cyclic loading, the difference was 5.3mm (SD 3) for the BKP group and 5.2mm (SD 3) for the RFK group (P > 0.1). The average cement volume used was 8.7mL (SD 1) for the BKP group and 4.8mL (SD 2) for the RFK group (P < 0.0001). Conclusions: On the basis of our results, the unipedicular RFK in osteoporotic compression fractures might represent a promising alternative for the clinical setting.