Kong Wayne Z, Goel Vijay K
Foster-Miller, Inc., Waltham, Massachusetts, USA.
Spine (Phila Pa 1976). 2003 Sep 1;28(17):1961-7. doi: 10.1097/01.BRS.0000083236.33361.C5.
The study examined the efficacy of the finite element models of various spinal segments in predicting the vibration response of the human spine.
To determine the optimal spinal segment finite element model to understand the effects of vibration on its biomechanics.
Several finite element models (one and two motion segments) have been proposed to look into the effects of vibration on the lumbar spine. However, they cannot be used to predict biomechanical parameters in the lumbar spine in response to whole body vibration.
A finite element model of the upper body from the head to the sacrum (H-S1) was generated. The H-=S1 model was altered to generate models of one motion segment (L3-L4), two motion segments (L3-L5), and the entire thoracolumbar spine and rib cage (T1-S1). The resonant frequencies of these models and effects of the trunk muscles and gravity were studied.
The resonant frequencies decreased with the increase in the number of motion segments. However, the decrease plateaued beyond the T1-S1 segment model. The first resonant frequency in the vertical direction for the H-S1 model was 8.32 Hz. Inclusion of the trunk muscles and the preload of self-weight changed it to 8.91 and 6.82 Hz, respectively.
Both the T1-S1 and H-S1 finite element models were able to predict vibration response of the human spine that closely matched in vivo experimental data reported in the literature.
本研究检验了各种脊柱节段的有限元模型在预测人体脊柱振动反应方面的有效性。
确定最佳的脊柱节段有限元模型，以了解振动对其生物力学的影响。
已经提出了几种有限元模型（一个和两个运动节段）来研究振动对腰椎的影响。然而，它们不能用于预测腰椎在全身振动时的生物力学参数。
生成了一个从头部到骶骨（H-S1）的上半身有限元模型。对H-S1模型进行修改，以生成一个运动节段（L3-L4）、两个运动节段（L3-L5）以及整个胸腰椎和胸廓（T1-S1）的模型。研究了这些模型的共振频率以及躯干肌肉和重力的影响。
共振频率随着运动节段数量的增加而降低。然而，在超过T1-S1节段模型后，下降趋于平稳。H-S1模型在垂直方向的第一个共振频率为8.32Hz。纳入躯干肌肉和自重预载后，分别变为8.91Hz和6.82Hz。
T1-S1和H-S1有限元模型都能够预测人体脊柱的振动反应，且与文献中报道的体内实验数据非常匹配。
