[Short-term effectiveness of percutaneous pedicle screw fixation combined with intravertebral allograft by different methods for thoracolumbar fractures].

OBJECTIVE:To investigate the short-term effectiveness of percutaneous pedicle fixation combined with intravertebral allograft by different methods for thoracolumbar fractures. METHODS:The clinical data of 94 patients with single segment thoracolumbar fracture who underwent percutaneous pedicle fixation combined with intravertebral allograft by different methods between October 2018 and October 2019 were retrospectively analyzed. According to the different methods of intravertebral allograft, they were divided into group A (bone grafting by Jack dilator, 40 cases) and group B (bone grafting by funnel, 54 cases). There was no significant difference between the two groups ( P>0.05) in the gender, age, body mass index, cause of injury, injured segment, Wolter index, time from injury to operation, and preoperative visual analogue scale (VAS) score, injured vertebral height ratio, and Cobb angle. The operation time, fluoroscopy frequency, allograft volume, and complications were recorded and compared between the two groups. VAS score of low back pain was used to evaluate the remission of clinical symptoms before operation, at 3 days, 3 months, 12 months after operation, and at last follow-up. The injured vertebral height ratio and Cobb angle were measured before operation, at 3 days, 3 months, and 12 months after operation. RESULTS:The operation time, fluoroscopy frequency, and allograft volume in group A were significantly higher than those in group B ( P<0.05). No complication occurred after operation, such as loosening or fracture of internal fixation. And bone grafting in the injured vertebrae healed at last follow-up. The VAS score, injured vertebral height ratio, and Cobb angle at each postoperative time point significantly improved when compared with preoperative ones ( P<0.05); compared with 3 days postoperatively, the VAS score improved further after 3 months, but the injured vertebral height ratio decreased and the Cobb angle increased, and the differences were significant ( P<0.05). There was no significant difference in the VAS scores of low back pain between the two groups at each time point after operation ( P>0.05); the injured vertebrae height ratio in group A was significantly higher than that in group B, and the Cobb angle was significantly lower than that in group B, all showing significant differences ( P<0.05). CONCLUSION:The intravertebral allograft via Jack dilator can restore the height and decrease the Cobb angle of the injured vertebrae, but accompanied with higher fluoroscopy frequency and longer operation time when compared with funnel bone grafting. For patients with single level thoracolumbar fractures, intravertebral allograft via Jack dilator is recommended.