Clinical Study Of Thoracolumbar Burst Fracture With Posterior Column Injury

Objective:From 2005 to 2010,177 patients with thoracolumbar burst fractures were treated in the department of spinal surgery in affiliated Hospital of Luzhou Medical College. A retrospective analysis was performed to study the injury of the posterior column in these patients by modern imaging techniques. The imaging changes and the incidence of posterior column injuries were documented to facilitate the understanding of the relationship of posterior column injury with thoracolumbar kyphosis, back pain and spinal cord injury. The clinical results of the treatments with 2 different anterior techniques for thoracolumbar burst fracture were retrospectively investigated and compared. These two methods indicate anterior screw plate system plus titanium mesh grafting and anterior screw rod system plus artificial bone grafting, respectively.Methods:The patients with thoracolumbar burst fractures treated in our Hospital from 2005 to 2010 were included. All the patients were surgically treated primarily by the senior surgeon(Dr. Wang Qing).The patients with the following conditions were excluded:(1) time from injury was more than 3 weeks; (2) serious osteoporosis; (3) paraplegia due to brain injury or the upper segments fractures; (4) pathological lesions of the vertebral body or congenital malformation. Document the general data, imaging findings of posterior column injuries, the fractures of pedicles, articular process, lamina and spinous process. The Cobb angle for thoracolumbar kyphosis, VAS score and Frankel grading for back pain and spinal cord injury were measured and followed up before and after surgery. Group the patients according to the methods of surgical strategies:Group A:thoracolumbar burst fracture without posterior column injury treated by anterior screw plate system plus titanium mesh grafting; Group B:thoracolumbar burst fracture without posterior column injury treated by anterior screw rod system plus artificial bone grafting. Group C:thoracolumbar burst fracture with posterior column injury treated by anterior screw plate system plus titanium mesh grafting; Group D:thoracolumbar burst fracture with posterior column injury treated by anterior screw rod system plus artificial bone grafting. Analyze the relationship among the severity of posterior column injury of thoracolumbar kyphosis, back pain and spinal cord injury. Compare the curative effect of patients with or without posterior column after surgical operation. Statistical analysis was performed with statistical software SPSS 13.0. Kai square test was performed to compare proportional values and t-test was performed to compare means, p<0.05 was considered statistically significant.Results:1) 81.9% of the patients with thoracolumbar burst fractures developed posterior column injury, including 9% of fractures of pedicles, 54.2% of laminar fracture,10.2% of articular process fractures,23.7% of transverse process fractures,31.1% of spinal process fractures and 37% of ligament rupture. No significant correlation was detected between the posterior ligamental structural damages with Cobb angle before surgical operation and VAS score. But there seems have some relevance between posterior column injury and preoperative Frankel grades. Severe injury of the posterior column in burst fracture can be regarded as an index of instability.2) For the 32 cases without posterior column injury, there is no significant difference between group A and B, concerning the general data and the clinical results treated with different procedures. This suggests that, in the patients without posterior column injury, comparable clinical results will be achieved using anterior screw plate system plus titanium mesh grafting or anterior screw rod system plus artificial bone grafting.3) For the 145 cases with posterior column injury, there is no significant difference of operative data between group C and D. The Cobb angle was larger after surgery which unchanged in group D, significant difference between the two groups (p<0.05); The Vas score and Frankel grade scores were both improved in the two groups without significant difference (p>0.05); The comparison results above suggest for cases of thoracolumbar burst fracture with posterior column injury treated by anterior screw plate system plus titanium mesh grafting or anterior screw rod system plus titanium mesh grafting both reached therapeutic purpose, but the latter is better than the former in correcting the Cobb angle and easing the back pain; There is no significant difference for the recovery of neural function in group C and D.Conclusion:In the patients with thoracolumbar burst fractures,81.9% of them developed posterior column fracture in which Lamina fractures and Ligament ruptures come first, latter is spinous and transverse process fractures, the end pedicle and articular fractures. No significant correlation was detected between the posterior ligamentous structural damages with Cobb angle and VAS score. But there seems have some relevance between posterior column injury and preoperative Frankel grades. In patients with no posterior column injury, the use of titanium mesh grafting and fixation with plate and screw system has been able to meet clinical requirements. While in patients with posterior column injury, the use of anterior screw-rod system plus artificial bone grafting is recommended with better thoracolumbar kyphosis correction and maintenance and long-term results of low back pain relief.