The effectiveness of posterior Schanz screw system in the anatomical restoration of thoracolumbar vertebral burst fractures: A 10-year single-institution experience.

Introduction: The Schanz screw system was developed for manual reduction of traumatic sagittal deformity of thoracic and lumbar vertebral fracture. The aim of this study was to evaluate clinical and radiological effectiveness of this system in the surgical treatment of thoracolumbar burst fractures (TLBFs) with severe kyphotic deformity without neurological deficit.

Materials and methods: A retrospective analysis was conducted on 101 patients who underwent short posterior fixation with transpedicular Schanz screws between 2012 and 2022 for single-level (T12 or L1) TLBFs. Clinical outcomes (Oswestry Disability Index [ODI] and Visual Analog Scale [VAS]) and radiological parameters (sagittal alignment and spinal canal dimensions) were assessed with a minimum 2-year follow-up.

Results: A total of 101 TLBFs patients with an average age of 48.1 years (range: 26-65) were included in this study. Intraoperative reduction of the Sagittal Kyphosis (SK) achieved an average of 12.31° ± 8.1°°, with a mean sagittal index (SI) correction of 15.23° ± 4.24°. At a minimum 2-year follow-up, the total amount of kyphosis reduction was maintained, with no significant difference between immediate postoperative and early follow-up measurements. Load-sharing score >8, body mass index >26, preoperative radiological parameters (SI, SK, and anterior body height [ABH] ratio), and postoperative ABH ratio were identified as significant predictors of correction loss >10°. At the final follow-up, all patients had minimal disability, with an average ODI of 7.9%. VAS scores also showed significant improvement, indicating substantial clinical effectiveness of the Schanz screw system in managing these complex spinal injuries.

Discussion: The Schanz screw system proved to be an effective and reliable method for treating TLBFs with severe kyphosis. The system's ability to achieve and maintain deformity reduction, coupled with favorable clinical outcomes, supported its use in the surgical management of these challenging spinal injuries.

Conclusion: The Schanz screw system offered a viable treatment option for severe kyphotic deformity in TLBFs.