Stackable carbon fiber cages for thoracolumbar interbody fusion after corpectomy: Long-term outcome analysis

Background: Reconstruction of the thoracolumbar spine after corpectomy is a challenge for fractures, infections, and tumors. Objective: To analyze fusion rates, clinical outcomes, and the percent of vertebral body coverage achieved by using stackable carbon fiber-reinforced polyetheretherketone cages in thoracolumbar corpectomies, and to measure the actual size of the cages and compare this measurement with the size of the vertebra(e) replaced by the cage. Methods: A retrospective study of 40 patients who underwent thoracolumbar corpectomies was performed. Preoperative imaging included plain films, computed tomography scans, and magnetic resonance imaging. Postoperatively, plain films and computed tomography scans were obtained, and the width of decompression and cross-sectional area of the cage were measured. The ratio of the area of the cage to the calculated area of the replaced vertebral body was used to determine the percent of vertebral body coverage. Results: The mean follow-up period was 43 months. Successful fusion was observed in 39 patients. One patient experienced cage subsidence with kyphosis. One additional patient incurred a neurological complication that was corrected without long-term consequence. The mean correction of sagittal alignment was 10°, and the mean width of bony decompression was 20 mm. The mean ratio of the area of the carbon fiber cage to the area of the resected vertebral body was 60%. Conclusion: Stackable carbon fiber cages are effective devices for achieving thoracolumbar fusions. No failures of the cages occurred over long-term follow-up. Excellent clinical and radiographic results were achieved by covering a mean of 60% of the vertebral body with the cage.