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不同负荷对人体全脊柱模型及人体脊柱稳定性的影响
Different Loads on the Effect of the Stability of Spinal Model and Spine of the Body
【作者】 蔡国梁;
【导师】 罗冬梅;
【作者基本信息】 北京体育大学 , 运动人体科学, 2012, 博士
【摘要】 目的:通过对人体全脊柱建模并在不同负荷下对全脊柱模型进行有限元分析,为人体实验推荐合理的负荷与负荷位置,之后进行人体实验研究较全面的阐释不同负荷对脊柱稳定性的影响,本研究希望能为背包者推荐比较合理的背包位置和背包负荷。方法:针对相关韧带和骨骼系统,应用有限元分析法进行研究;针对肌肉系统采用表面肌电技术;在不同负荷下对躯干前倾角和足底压力中心位移的变化进行实验研究。结果:首先,利用有限元分析法建立了全脊柱模型,选择了O%BW-45%BW十种负荷(以5%BW递增),进行模型的稳定性研究,当载荷小于15%BW时,T7组、T12组、L3组的最大位移几乎都在稳定位移3mm以下,只有T7组在负荷达15%BW时最大位移为3.069mm。其次,在七种负荷(即O%BW、15%BW/T7、15%BW/T12、15%BW/L3、30%BW/T7、30%BW/T12和30%BW/L3)下,进行脊柱稳定性测试。最长肌、髂肋肌与腹直肌的变化趋势大致相同,腹外斜肌的变化没有统计学差异,均表现为iEMG和RMS增加,而MF和MPF减小。30%BW负荷下,髂肋肌和最长肌的iEMG和RMS增大明显,MF和MPF下降明显;腹直肌的iEMG和RMS增大,MF和MPF下降;腹外斜肌的肌电信号变化较15%BW负荷下变化不明显。在15%BW/L3的负荷下,iEMG和RMS增加的相对平缓,而MF和MPF减小的相对平缓;躯干前倾角随着负荷的增加而增加,变化有统计学差异;不同负荷下,COP位移变化不具有统计学差异。结论:(1)经过对全脊柱模型的验证,证明本研究成功的建立了人体全脊柱模型;(2)对人体全脊柱进行有限元分析,发现背包负荷为30%BW时,只有在L3位置时,脊柱是稳定的:当背包负荷为15%BW时,背包位于L3,T12,T7三个位置时,脊柱都是稳定的:(3)不同负荷下,随着负荷的递增,躯干前倾角在减小,与肌肉共同维持身体姿势的平衡与脊柱的稳定性;不同负荷下,足底压力中心位移的变化不显著,提示我们在静态负荷下,身体姿势的平衡与脊柱的稳定性柱要是由肌肉和躯干前倾来维持的(4)不i同负荷下,腹直肌、骼肋肌与最长肌的肌电信号变化明显,提示我们在静态负荷下,腹直肌、髂肋肌与最长肌较多的参与了维持脊柱的稳定性。
【Abstract】 Objective:Through theoretical and experimental studies a more comprehensive interpretation of different loads on the stability of the spine, we hope for the backpack to recommend a more reasonable location of the backpack and the backpack load. Methods:(1) surface EMG;(2) FEA;(3) the experimentation for TFL and COP. Results:under0%BW、5%BW、10%BW、15%BW、20%BW、25%BW、30%BW、35%BW、40%BW and45%BW, when the backpack load is less than15%BW, the maximum displacement is in the T7group, almost all of the displacement is below3mm in the L3group of the maximum displacement of15%BW, when the backpack load of20%BW and25%BW, the maximum displacement of the L3is about2.6mm, while the T7and T12is more than3mm but less than3.5mm. under seven kinds of load:0%BW,15%BW/T7,15%BW/T12,15%BW/L3,30%BW/T7,30%BW/T12,30%BW/L3, the sEMG changes of the multifidus muscle, the erector spinae, rectus abdominis and external oblique muscle are consistent, that is, with the increment of load, concentic iEMG and RMS increases, while the MF and MPF decreases. Under the load of15%BW/L3of concentric iEMG and RMS increase is ralatively flat, while the MF and MPF deceases relatively flat; the changes of the TFL is significant; but the changes of the COP is not. Conclusions:(1) under different loads, the stability of the spine is as follows:L3>T12>T7;(2) under the backpack load of15%BW, the backpack is located in L3, T12, T7, the spine is stable;(3) under different loads, the external oblique EMG does not change significantly, suggesting that under static load, the exernal oblique muscle is less involved in maintaining the stability of the spine;(4) under different loads, rectus abdominis, multifidus muscle and erector spinae sEMG change significantly, suggesting that under static load, the rectus abdominis, multifidus muscle and erector spinae more involved in maintaining the stability of the spine.
【Key words】 stability of the spine; finite element analysis; surfaceelectromyography; trunk forward lean; center of pressue;