Results of treatment of unstable thoracolumbar burst fractures using pedicle instrumentation with and without fracture-level screws.

Background: Two different techniques of short-segment instrumentation, with and without a pedicle screw at the fracture level, were compared in thoracolumbar burst fractures in neurologically intact (ASIA-E) patients. The sagittal index, kyphosis angle (Cobb), canal compromise ratio, and compression ratio of the anterior vertebral height were analyzed.

Methods: Seventy patients who underwent short-segment stabilization for thoracolumbar (T11-L2) burst fractures in our clinic between 2008 and 2012 were included in this retrospective study. In 35 patients (group 1), a pedicle screw was placed only one level down and one level up from the fracture level. In another 35 patients (group 2), a screw was placed at the fracture level in addition to the short segment. Only neurologically intact patients with burst fractures according to the Denis classification were included. The patients were evaluated according to their age/gender, trauma etiology, and fracture level. Their preoperative and most recent postoperative follow-up radiographs and CTs were evaluated in terms of the sagittal index, kyphosis angle (Cobb), ratio of canal compromise, and anterior vertebral height.

Results: The two groups were similar in their ages, follow-up periods, and severity of the deformity and fracture. When the pedicle screw was placed at the fracture level in addition to short-segment stabilization, statistically significant improvements in the sagittal index (p < 0.001), local kyphosis (Cobb) angle (p = 0.006), and compression ratio of the anterior vertebral height (p = 0.002) were observed. Concerning the ratio of canal compromise according to the CT findings (p = 0.189), moderate differences were found.

Conclusions: Short-segment stabilization in thoracolumbar burst fractures with additional screws at the level of the fracture results in an improved kyphosis correction, sagittal index, and compression ratio of the anterior vertebral height. However, long-term follow-up is needed to determine the clinical significance of these findings.