College of Biomedical Engineering, Taiyuan University of Technology
目的 通过对兔单椎进行动态冲击破坏试验,并与静态压缩实验进行对比,研究椎体轴向冲击的损伤机制,为临床诊断提供参考性建议。方法 通过落锤动态冲击实验装置,利用示波器和高速摄影获得力传感器的电压波形图和椎体冲击的详细过程。结果 胸、腰椎静态载荷均值分别为910 N和947 N,胸、腰椎动态载荷均值分别为1196 N和1026 N；胸、腰椎动荷系数的平均值为1.37和1.08；静载条件下,胸、腰椎等效应力的平均值为15.28 MPa和12.51 MPa,动载条件下,胸、腰椎等效应力的平均值为20.03 MPa和13.56 MPa；动态冲击过程中,纵向应变与横向应变的均值为-0.3和-0.005(压缩)；动载条件下,椎骨的破坏能量从0 J一直增大到4.4 J。结论 在动、静态实验条件下,同一椎体的动态载荷大于静态载荷；胸椎的动荷系数平均值大于腰椎的；胸椎的应力值大于腰椎；椎体受到轴向冲击力时纵向应变大于横向应变；椎体的能量增长呈现先缓慢后快速的过程。本文的研究可以为临床实践中人脊柱椎体损伤的预防和康复提供指导意见。
Objective The dynamic impact failure test of rabbit single vertebra was carried out, and compared with the static compression experiment, the damage mechanism of the axial impact of the vertebral body was studied, and the reference for clinical diagnosis was provided. Methods The voltage waveform diagram of the force sensor and the detailed process of the vertebral impact are obtained by the oscilloscope and high-speed photography through the drop hammer dynamic impact experimental device. Results The mean static load of the thoracic and lumbar spine were 910 N and 947 N respectively; the mean dynamic load of the thoracic and lumbar spine were 1196 N and 1026 N respectively; the mean values of the thoracic and lumbar dynamic load coefficients were 1.37 and 1.08; under the condition of static load, the average stress of thoracic and lumbar spine is 15.28 MPa and 12.51 MPa; under the dynamic load conditions, the average stress of thoracic and lumbar spine is 20.03 MPa and 13.56 MPa; during dynamic impact, the mean value of longitudinal strain and transverse strain is -0.3 and -0.005 (compression); under dynamic conditions, the destruction energy of vertebrae increases from 0 J to 4.4 J. Conclusion Under dynamic and static experimental conditions, the dynamic load of the same vertebral body is greater than the static load; the mean value of the dynamic load coefficient of the thoracic vertebra is larger than that of the lumbar vertebrae; the equivalent stress value of the thoracic vertebra is greater than that of the lumbar vertebrae; The axial strain of vertebra under impact is greater than the transverse strain; the energy growth of the vertebral body presents a first slow and then rapid changing process. This study can provide guidance for the prevention and rehabilitation of human vertebral body injury in clinical practice.