Anterior column reconstruction of the thoracolumbar spine with a new modular PEEK vertebral body replacement device: retrospective clinical and radiologic cohort analysis of 48 cases with 1.7-years follow-up.

PURPOSE To evaluate whether a new PEEK vertebral body replacement can maintain the sagittal alignment as an anterior column reconstruction device in thoracic and lumbar spinal defects due to trauma or tumor. METHODS Retrospective review of 48 patients who underwent a corpectomy between T5 and L5 due to trauma or tumor and were stabilized with the new PEEK vertebral body replacement, between 2013 and 2017. We excluded patients who underwent a corpectomy for infection or degenerative disease and patients without complete follow-up in our institution. The primary outcome was the bi-segmental kyphotic angle (BKA). Secondary outcomes were the assessment of pedicle screw loosening, cage height, and subsidence or tilting of the cage. The clinical outcomes were assessed through the COMI-Score, EuroQol-5D, and Karnofsky indexes. Bony fusion and complications were registered. RESULTS After the surgery BKA decreased by 12.1° (p < 0.001). At the end of the follow-up, we observed a mean loss of reduction of 1.6° (p = 0.002). This was accompanied by an increase in subsidence of 2.1 mm (p < 0.001) and mean tilting of the cage of 1.4° (p = 0.003). The height of the cage and other parameters did not experience any changes. Clinically, the COMI-Score (p = 0.02) and the EuroQol-5D Index (p = 0.012) showed significant improvement, same as Karnofsky-Index (p = 0.015) at final follow-up. The fusion rate according to Bridwell was 92.1%. The 2% late complications were related to implant malpositioning. CONCLUSION The new PEEK expandable vertebral body replacement is effective and safe in thoracic and lumbar anterior column reconstruction in tumor and trauma diseases.