45天-6°头低位卧床对自由行走步态特性的影响  

Changes of Free Walk Gait Pattern After 45-day Head-down Bed Rest

作　　者：谈诚[1] 夏永明 赵琦[1] 国耀宇[1] 曹毅[1] 陈文娟[1] 王靖宇[1] 何思杨[1] 王政[3] 严曲[3] 王春慧[3] 陈晓萍[1] 万玉民[1] 李莹辉[1] 白延强[1] 

机构地区：[1]中国航天员科研训练中心,航天医学基础与应用国家重点实验,北京100094 [2]北京理工大学机械与车辆工程学院,北京100081 [3]中国航天员科研训练中心,人因工程国防重点实验室,北京100094

出　　处：《航天医学与医学工程》2013年第6期467-470,共4页Space Medicine & Medical Engineering

基　　金：国家重点基础研究发展计划973项目(2011CB711000);航天医学基础与应用国家重点实验室研究基金资助项目(SMFA11B02);中国航天医学工程预先研究项目(2011SY5405002)

摘　　要：目的探讨长期头低位卧床对人体自由行走时步态特性的影响。方法 8名健康成年男性志愿者进行-6°头低位45 d卧床实验。卧床前第6天(R-6),卧床后第1天(R+1)及第10天(R+10)进行自由无约束行走步态测试。使用高速摄像系统对行走过程中的步态时相参数进行分析,使用三维力台和应力板进行足底作用力的测试,同时对行走时的股直肌、腓肠肌内侧头、外侧头的肌电信号进行采集。结果头低位卧床45 d可导致步长和步速的显著降低,以及步态周期和接触时间的明显增加(P<0.05)。足底受力的结果表明,45 d的前后方向上的作用力明显减少(P<0.05),但垂直和左右方向上的作用力并未受到影响(P>0.05),足底冲量和加载速度均有显著的增加(P<0.05),除前后方向作用力外,其它指标在卧床后第10天仍未恢复正常。肌电结果显示45 d的头低位卧床后,中位功率频率有明显的降低(P<0.05),但在R+10恢复。结论 45 d头低位卧床可导致人体步态特性发生显著改变,R+10 d后亦不能完全恢复。Objective To investigate the effects of long-term simulated microgravity environment on human free walk gait pattern. Methods Eight healthy male volunteers joined the 45-day head down bed rest （HDBR）. They were tested the free walk gait pattern at the 6th day before HDBR（ R -6）, the 1st day after HDBR（ R ＋ 1 ） , and the 10th day after HDBR （R ＋ 10）. During the walking, a high speed camera system was used to re- cord and analyze the gait cycle parameters. The ground reaction force and foot pressure were also acquired by 3-dimension force plate and foot pressure distribution system. And the muscle activity of rectus femoris （RF）, gastrocnemius medialis （GM） and gastronemius lateralis （GL） were also analyzed. Results The step length and velocity were significantly decreased after 45-day HDBR, while the gait cycle and contact time increased （ P 〈 0.05）. Data of ground reaction force and foot pressure distribution showed that the antero-posterior force dur- ing walk after 45-day HDBR were extremely lower than before HDBR, but there were no changes in vertical and medio-lateral force. The impulses, and loading velocities at both feet were increased after 45-day HDBR. Except the antero-posterior force, all other parameters were not back to normal at R ＋ 10. The results of sur- face electromyogramphy in low limb muscle indicated that there were no significant changes in muscle activity during walking before and after HDBR. However, the mean power frequencies（MPF） in RF, GM, GL were all decreased at R ＋ 1 （ P 〈 0.05 ） , and back to normal at R ＋ 10. Conclusion The gait pattern of free walk has changed after 45-day HDBR, and could not back to normal at R ＋ 10 completely.

关 键 词：模拟失重 头低位卧床 自由行走步态 足底压力 肌电 

分 类 号：R852.22[医药卫生—航空、航天与航海医学]