Short-Segment Fixation Without Fusion for Thoracolumbar Burst Fractures With Neurological Deficit Can Preserve Thoracolumbar Motion Without Resulting in Post-traumatic Disc Degeneration: A 10-Year Follow-up Study

Study Design. Prospective consecutive series. Objective. To evaluate the post-traumatic disc degeneration and range of motion 10 years after short-segment fixation without fusion for thoracolumbar burst fractures with neurological deficit. Summary of Background Data. Early clinical results of short-segment fixation without fusion for thoracolumbar burst fractures were satisfactory. However, the long-term results have not been reported, and post-traumatic disc degeneration and preservation of thoracolumbar motion have not been elucidated. Methods. Twelve patients who had thoracolumbar burst fractures and associated incomplete neurological deficit, operatively treated within 4 days of admission and had their implants removed within 1 year, were prospectively followed for at least 10 years. Following indirect reduction and pedicle screw fixation, transpedicular intracorporeal hydroxyapatite grafting to the fractured vertebrae was performed. Results. Sagittal alignment was improved from a mean preoperative kyphosis of 17° to −2° (lordosis) by operation, but was found to have slightly deteriorated to 2° at the final follow-up observation. With respect to back pain, 8 patients did not report back pain. Three reported occasional minimal pain, and 1 reported moderate pain. None reported severe pain or needed daily dosages of analgesics. Regarding disc degeneration, the shape of the disc adjacent to the fractured vertebra had not changed from the preoperative to the 10-year postoperative magnetic resonance image (MRI). Although signal intensity of the disc had decreased by 1 grade from the preoperative to the 2-year postoperative MRI, the intensity had not changed from the 2-year postoperative MRI to the 10-year postoperative MRI. At the 10-year follow-up, flexion-extension radiographs revealed that a mean range of motion at the disc adjacent to the fractured vertebra was 12º (range; 5–19). Conclusion. This unprecedented 10-year follow-up study demonstrated that posterior indirect reduction, transpedicular hydroxyapatite grafting, and pedicle screw fixation does not require fusion to a segment, thereby preserves thoracolumbar motion without resulting in post-traumatic disc degeneration. Level of Evidence: 4