Abstract：Objective To investigate efficacy of KumaFix posterior spinal screw/rod system (KumaFix system) for thoracolumbar fractures. Methods Thirty patients with type A3 thoracolumbar fractures treated from June 2011 to June 2012 were divided into Group A and Group B according to odd and even number. Group A (n=15) underwent reduction and fixation with KumaFix system in combination with transpedicular bone grafting of fractured vertebrae. There were 7 males and 8 females at average age of (40.5±5.1) years (range, 21-52 years). Group B (n=15) underwent posterior reduction and fixation with U-shaped screw/rod system in combination with transpedicular bone grafting of fractured vertebrae. There were 8 males and 7 females at average age of (41.3±4.8) years (range, 22-51 years). Two groups were analyzed and compared in aspects of operation time, blood loss, visual analogue scale (VAS), anterior vertebral height ratio, kyphosis angle, spinal canal encroachment ratio, and Oswestry disability index (ODI). Results All patients were followed up for average 13.2 months. Operation time was shorter in Group A than in Group B (P<0.05), but there was no significant difference in blood loss between the two groups (P>0.05). Both groups achieved obvious improvement in aspects of VAS, anterior vertebral height ratio, kyphosis angle, spinal canal encroachment ratio after operation (P<0.05). ODI score was improved for the two groups after operation (P<0.05) and was better in Group A than in Group B at the last follow-up (P<0.05). Conclusions For treatment of type A3 thoracolumbar vertebral body fractures, the KumaFix system is able to achieve gradual, smooth and controllable distraction reduction that is conducive to the implement of transpedicular bone grafting of fractured vertebrae in comparison with the U-shaped screw/rod system. In the meantime, the KumaFix system avoids negative effect of internal fixation on adjacent articular process.
HAO Ding-jun,HE Bao-rong,XU Zheng-wei et al. KumaFix fixation system for treatment of type A3 thoracolumbar vertebral body fractures[J]. CHINESE JOURNAL OF TRAUMA, 2013, 29(6): 498-502.
［1］Van Herck B, Leirs G, Van Loon J. Transpedicular bone grafting as a supplement to posterior pedicle screw instrumentation in thoracolumbar burst fractures. Acta Orthop Belg, 2009, 75(6):815-821.
［2］Knop C, Fabian HF, Bastian L, et al. Late results of thoracolumbar fractures after posterior instrumentation and transpedieular bone grafting. Spine, 2001, 26(1):88-99.
［3］Kim HJ, Chun HJ, Kang KT, et al. The Biomechanical effect of pedicle screws' insertion angle and position on the superior adjacent segment in 1 segment lumbar fusion. Spine,2012,37(19):1637-1644.
［4］Kallemeier PM, Beaubien BP, Buttermann GR, et al. In vitro analysis of anterior and posterior fixation in an experimental unstable burst fracture model. J Spinal Disord Tech, 2008, 21(3):216-224.
［5］Butt MF, Farooq M, Mir B, et al. Management of unstable thoracolumbar spinal injuries by posterior short segment spinal fixation.Int Orthop, 2007, 31(2):259-264.
［6］Wang XY, Dai LY, Xu HZ, et al. Kyphosis occurrence after posterior short-segment fixation in thoracolumbar burst fractures. J Neurosurg Spine, 2008, 8(3):246-254.
