Abstract: Objective: To explore the clinical effects of the posterior pedicle fixation of different segments in the treatment of severe thoracolumbar spine fractures.Methods: One hundred and twenty-seven severe thoracolumbar spine fractures patients treated with posterior pedicle fixation in 2016 were divided into the short segment group(67 cases),long segment group(35 cases),and injured vertebral segment group(25 cases) according to the different fixed segments.The operation situation in three groups were observed.Three groups were followed up for 1 to 2 years,and the clinical effects among three groups were compared.Results: The operation time and intraoperative blood loss in long segment group,injured vertebral segment group and short segment group gradually decreased(P<0.01),and the postoperative bed time in short segment group,injured vertebral segment group and long segment group gradually decreased(P<0.01).The differences of the postoperative anterior border height percentage of injured vertebrae and recovery of Cobb angle between long segment group and injured vertebral segment group were not statistically significant(P>0.05),and which was better than that in short segment group(P<0.01).The differences of the Oswestry Dability Index scores among three groups were not statistically significant(P>0.05).No serious adverse reaction occurred in three groups.Conclusions: The short segment fixation treatment has shorter operation time,and little intraoperative blood loss.The advantage of long segment fixation and the injured vertebral short segment fixation in the reset and ensuring the injured vertebral anterior edge height are more obvious.