A comparative analysis of the efficacy of short-segment pedicle screw fixation with that of long-segment pedicle screw fixation for unstable thoracolumbar spinal burst fractures

The indications for operative treatment and type of stabilization procedures for the treatment of thoracolumbar burst fracture remain controversial. As surgical reconstruction for the thoracolumbar burst fracture, both long-segment pedicle screw fixation and short-segment pedicle screw fixation including fractured vertebral body have been used widely. The present study evaluated the efficacy of short-segment fixation compared with that of long-segment fixation in terms of the radiological and clinical outcomes in unstable thoracolumbar burst fractures. From January 2007 to December 2012, 76 patients with thoracolumbar burst fracture underwent posterior pedicle screw fixation consecutively in our hospital. These patients were divided into two groups: the short-segment group, which included patients who underwent short-segment pedicle screw fixation including the fractured vertebral body, and the long-segment group, which included patients who underwent long-segment pedicle screw fixation (2 levels above and 1 level below the fractured vertebral body). There were 44 and 32 patients in the long-segment and short-segment group, respectively. Radiological assessment of the kyphotic angle was performed using the Cobb method immediately after the operation and at 3, 6, and 12 months postoperatively. The clinical outcomes were evaluated using the modified Mcnab criteria at the last follow-up. The sex ratio, mean age of patients, and composition of the fractured vertebral body were similar in both groups. In the long-segment and short-segment group, 37 (84.1%) and 26 (81.3%) cases showed excellent or good outcomes, respectively. The mean kyphotic angle at the immediate postoperative period was 7.3° ± 5.8° and 0.6° ± 11.9° in the long-segment and short-segment group, respectively. The average loss of kyphosis correction was 5.4° ± 4.4°, 8.6° ± 6.2°, and 10.5° ± 4.8° in the long-segment group and 4.1° ± 3.6°, 6.2° ± 5.2°, and 7.5° ± 4.4° in the short-segment group at 3, 6, and 12 months postoperatively, respectively. There was no statistically significant difference in the average loss of kyphosis correction between the two groups (p > 0.05). In conclusion, short-segment pedicle screw fixation including the fractured vertebral body might be as effective as long-segment pedicle screw fixation for the treatment of unstable thoracolumbar spinal burst fracture.