Analysis of the Effect and Prognostic Factors Associated with Postural and Instrumental Reduction in Thoracolumbar Burst Fractures

BACKGROUND: Axial load on thoracolumbar junction, both mechanical and anatomical transitional zone, causes the compression and flexion of the spine, and consequently thoracolumbar burst fractures. OBJECTIVE: This study aimed to investigate the effect and prognostic factors associated with the postural and instrumented reduction on the restoration of vertebral height and kyphosis angle in thoracolumbar burst fractures. MATERIAL AND METHODS: This retrospective cohort study was conducted on 41 patients with A3, A4, and B type thoracolumbar burst fractures, subjected to postural and instrumented reduction for the restoration of vertebral height and kyphosis angle. The magnitude and correction of kyphotic deformity and percentage of vertebral body collapse were measured before and after postural reduction, and after instrumental insertion to find if they were affected by fracture type and level, time-to-surgery, and use of pedicular screws at the fractured level. RESULTS: Postural and instrumental reduction significantly improved both the kyphosis angle and the percentage of vertebral body height, regardless of AO types (p.value <0.001 and p.value <0.001, respectively). AO type A3, and A4 comparing to type B, has better restoration of kyphosis angle by postural (p-value=0.013, p-value=0.007, respectively) and instrumental reduction. (p-value=0.006, p-value=0.014, respectively). Evaluation of time to surgery showed that performing operation during the first four days would result in better correction of kyphosis angle (p-value 0.015). CONCLUSION: AO type A3, and A4, time to surgery before 4 days, and fracture level at L2 were favorable prognostic factors to better restoration of kyphosis angle using both postural and instrumented reduction.