-6°卧床7d对平衡功能的影响

Effects of 7 d -6° Bed-rest on Postural Equilibrium.

目的使用电子计算机化动态姿态平衡仪 (CDP)定量评价 - 6°卧床 7d对人体平衡功能的影响及前庭、本体感觉和视觉对人体维持平衡的贡献。方法被试者为 8名健康男性 ,分别于卧床前、起床后、恢复 4d测试感觉整合试验 (SOT)和运动控制试验 (MCT)。结果在SOT试验状态 1 (即睁眼 ,平台和视景环境固定 )、5(即闭眼 ,视景环境固定 ,平台随重心晃动而晃动 ) ,起床后平衡得分与卧床前相比有明显降低 (P <0 .0 5) ,4d后平衡得分恢复正常。在SOT试验状态 1、2 (即闭眼 ,平台和视景环境固定 )、3(即睁眼 ,平台固定 ,视景环境随重心晃动而晃动 ) ,起床后平衡策略得分与卧床前相比有明显降低 (P <0 .0 5) ,4d后恢复正常。本体感觉和视觉 ( 2 /1 ,3/1 )的依赖性起床后比卧床前明显增大 (P <0 .0 5) ,4d后恢复正常。在SOT试验状态 1、4(即睁眼 ,视景环境固定 ,平台随重心晃动而晃动 )、6(即睁眼 ,视景环境和平台都随重心晃动而晃动 ) ,起床后重心排列与卧床前相比有明显的前倾趋势 ,恢复 4d后 ,状态 1、6重心排列恢复正常 ,而状态 4未恢复。MCT试验卧床前后运动反应潜时未发现变化。结论 - 6°HD BR 7d对平衡功能有显著影响 。

Objective To quantitatively assess the effects of 7 d -6° hea d -down bed-rest (HDBR)on postural equilibrium and to investigate the contribu tions of vestibular,somatosensory and visual informations to postural equilibriu m. Method Eight healthy males,aged 33～42 years ,were exposed to -6 ° head-down tilt bed rest for 7 d .Sensory Organization Test (SOT)and Motor Co ordination Test (MCT) were measured before and after HDBR,and day 4 of recovery. Result Equilibrium scores of SOT in condition 1(eyes opened,pla tform and visual scence environment fixed),5(eyes closed ,visual scence environm ent fixed,platform movable) were significantly lower as compared with pre-HDBR value,and recovered to pre-HDBR level on day 4 of recovery.Postural strategy sc ores of SOT in condition 1,2(eyes closed, platform and visual scence environment fixed)and 3(eyes opened,platform fixed, visual scence environment movable) were significantly lower as compared with pre-HDBR value,and recovered to pre-HDBR level on day 4 of recovery. The dependance of somatosensory and visual informat ion (ratio pair codition 2/condition 1,condition 3/condition 1 in sensory analys is) was significantly higher as compared with pre-HDBR value,and recovered on d ay 4 of recovery.Mean SOT alignment scores in conditions 1,4(eyes opened, visual scence environment fixed, platform movable)and 6(eyes opened, platform and visu al scence environment movable)were significantly higher as compared with pre-HD BR value,and only the scores of conditions 1,6 were recovered on day 4 of recove ry,but that of condition 4 did not.Mean postural-evoked response latencies of M CT were not significantly different as compared with pre-HDBR value. Conc lusion 7 d -6°head-down tilt bed-rest has significant effects on postur al equilibrium.The contributions of somatosensory and visual informations to po stural equilibrium are increased.