The clinical outcomes of percutaneous self-expanding forceful reduction screw system for the treatment of thoracolumbar fracture with severe loss of vertebral height

Abstract

Objective To explore the safety and effectiveness of a novel percutaneous self-expanding forceful reduction screw system in the treatment of thoracolumbar fracture with severe vertebral height loss. Methods Thirty-eight patients of thoracolumbar fracture with more than 50%vertebral height loss were treated with the novel percutaneous self-expanding forceful reduction screw between March 2014 and June 2015. The screw system is a single plane screw with a reduction angle of 0,3,6,9 degrees. During the operation, the fracture vertebral body was automatically restored during the locking process of the top cap. All the patients were single vertebral fractures. Percutaneous screw fixation and reduction was used in the operation. Two groups of screws were used to fix the two adjacent vertebrae of the injured vertebra and to restore the injured vertebral body, without fusion treatment. The vertebral body index (VBI), height of the anterior margin of fractured vertebra (HAMFV), vertebral body angle (VBA), bisegmental Cobb angle (BCA), visual analog scale (VAS) and Oswestry disability index (ODI) of the patients before and after operation, 6 months after operation, and at the end of the follow-up were compared. The scoring results were compared using a t test. Results The operation was completed successfully in 38 cases. A total of 152 screws were placed. The accuracy rate of CT evaluation was 98.7%. The average operation time was 90.7±21.9 min, and the average intraoperative bleeding amount was 89.2±31.9 ml. The patients' preoperative VBI, HAMFV, VBA, BCA, VAS and ODI scores were 0.38±0.07, 0.38±0.06, 25.45°±4.54°, 18.66°±8.57°, 7.76±1.02, and 44.58%±2.33%, respectively. The postoperative measurements were 0.93±0.03, 0.95±0.02, 3.71°± 1.35°, 5.84°±6.80 °, 4.29±1.16 and 24.37%±1.88%. At the last follow-up, the measurements were 0.92±0.03, 0.94±0.02, 3.89° ±1.31°,6.05°±7.00°, 1.71±0.65 and 5.95%±2.67%. There was significant difference between the preoperative and postoperative data, as well as the preoperative and the last follow-up data (P<0.05). Conclusion In the treatment of thoracolumbar fractures with severe loss of vertebral height, the novel percutaneous self-expanding forceful reduction screw system has achieved satisfactory vertebral height restoration and kyphosis correction. Key words: Thoracic vertebrae; Lumbar vertebrae; Spinal fractures; Surgical procedures, minimally invasive; Internal fixators