ObjectiveTo compare the effective of short-segment pedicle instrumentation with bone grafting and pedicle screw implanting in injured vertebra and cross segment pedicle instrumentation with bone grafting in injured vertebra for treating thoracolumbar fractures. MethodsA prospective randomized controlled study was performed in 40 patients with thoracolumbar fracture who were in accordance with the inclusive criteria between June 2010 and June 2012. Of 40 patients, 20 received treatment with short-segment pedicle screw instrumentation with bone grafting and pedicle screw implanting in injured vertebra in group A, and 20 received treatment with cross segment pedicle instrumentation with bone grafting in injured vertebra in group B. There was no significant difference in gender, age, affected segment, disease duration, Frankel grade, Cobb angle, compression rate of anterior verterbral height, visual analogue scale (VAS) score, and Japanese Orthopaedic Association (JOA) score between 2 groups before operation (P>0.05). The operation time, blood loss, Cobb angle, compression rate of anterior vertebral height, loss of disc space height, Frankel grade, VAS and JOA scores were compared between 2 groups. ResultsThere was no significant difference in the operation time and blood loss between 2 groups (P>0.05). Primary healing of incision was obtained in all patients, and no early complication of infection or lower limb vein thrombus occurred. Forty patients were followed up 12-16 months (mean, 14.8 months). No breaking or displacement of internal fixation was observed. The improvement of Frankel grading score was 0.52±0.72 in group A and 0.47±0.63 in group B, showing no significant difference (t=0.188, P=0.853) at 12 months after operation. The Cobb angle, compression rate of anterior verterbral height, and VAS score at 1 week and 12 months, and JOA score at 12 months were significantly improved when compared with preoperative ones in 2 groups (P<0.05). No significant difference was found in Cobb angle, disc space height, VAS score, and JOA score between 2 groups at each time point (P>0.05), but the compression rate of anterior verterbral height in group A was significantly lower than that in group B (P<0.05). The loss of disc space height next to the internal fixation or the injured vertebra was observed in 2 groups at 12 months, but showing no significant difference (P>0.05). ConclusionCompared with cross segment pedicle instrumentation, short-segment pedicle screw instrumentation with bone grafting and pedicle screw implanting in injured vertebra can recover and maintain the affected vertebra height in treating thoracolumbar fractures, but it could not effectively prevent degeneration of adjacent segments and the loss of kyphosis correction degree.