摘要
目的构建胸腰椎骨折经伤椎单节段固定三维有限元模型，研究该固定方法对邻近节段的影响。方法利用CT扫描数据建立脊柱T10～L2正常模型、T12骨折模型及经伤椎单节段固定模型和短节段固定模型。分析各模型在轴向压缩、前屈、后伸、侧屈及轴向旋转下，伤椎固定邻近椎间盘及椎体的应力情况。结果在前屈、后伸及侧屈时，骨折模型T10～T11节段髓核及纤维环和L1～L2纤维环应力较正常模型有较明显的升高，总体升高幅度约为75％，L1～L2髓核增高约46％。短节段固定后，应力值分别降至23％、12％；经伤椎单节段固定分别降至18％、8％。骨折模型T10下终板及L2上终板的应力增高分别约为24％、43％。内固定后，升高的应力明显降低，比正常模型略有增加，短节段固定约为8％；经伤椎单节段固定约为4％。固定后T10下终板的应力明显减低，与正常模型相应终板应力比较，分别下降2％和8％。结论对于胸腰段单节段不完全骨折，与常规短节段固定相比，经伤椎单节段固定邻近节段的应力更小，是一种良好的治疗选择。
Objective To establish a three-dimensional finite element model of thoracolumbar fractures treated by mono-segmental instrumentation in the fractured part for testing effect of such fixation mode on adjacent segments. Methods CT scanning data of T10-L2 were used to build a normal model at T10-L2 region, a fracture model at T12 segment as well as a mono-segment fixation or short-segment fixation model. Stress of discs and vertebral body adjacent to the fixed vertebrae were tested in axial compression, anteflexion, extention, lateroflexion, and axial rotation. Results The fracture model presented significant increase concerning stress of nucleus pulposus and annular fibrosus at Tx0-T11 segments and annular fi- brosus at L1-L2 segments in anteflexion, extention, and lateroflexion when compared with the normal model. General raise range of the stress reached around 75%, but was dropped to 23% after short-segment fixation and to 18% after mono-segmental fixation. And again, stress of nucleus pulposus at Lj-L2 segments was in- creased by 46% or so, which was declined to 12% after short-segment fixation and to 8% after mono-segmental fixation. Stress at lower endplate of Tj0 and at upper endplate of L2 in the fracture model group were increased by 24% and 43% respectively when compared to the normal model, but both presented a notable drop after internal fixation. The latter was decreased to a level slightly higher than that of model group, namely 8% more after short-segmental fixation and 4% more after mono-segmental fixation; the former was decreased to a level even lower than that of control group, namely 2% less after short-segmental fixation and 8% less after mono-segmental fixation. Conclusion Mono-segmental fixation reduces adjacent disc stress in contrast to conventional short-segmental fixation and hence is an effective alternative treatment of monosegmental thoracolumbar fractures.
出处
《中华创伤杂志》
CAS
CSCD
北大核心
2013年第6期507-510,共4页
Chinese Journal of Trauma
关键词
脊柱骨折
胸椎
腰椎
骨折固定术
有限元分析
Spinal fractures
Thoracic vertebrae
Lumbar vertebrae
Fracture fixation
Finite element analysis
