Owings T M, Pavol M J, Foley K T, Grabiner M D
Department of Biomedical Engineering, The Lerner Research Institute, The Cleveland Clinic Foundation, Ohio 44195, USA.
J Am Geriatr Soc. 2000 Jan;48(1):42-50. doi: 10.1111/j.1532-5415.2000.tb03027.x.
To determine, in healthy older adults, the relationship between postural steadiness, stability limits, and the ability to recover balance from three postural disturbances requiring anteriorly directed stepping responses.
Analysis of multiple motor tasks in a cross-sectional sample of healthy older adults.
A biomechanics research laboratory.
Fifty women and 29 men aged 65 or older, all healthy, living in the community, participated in this study. Subjects were examined by a geriatrician to identify the presence of exclusionary factors.
Anterior-posterior and medial-lateral excursion distances of the center of pressure during quiet standing (postural steadiness), static leaning (static stability limits), and dynamic swaying (dynamic stability limits) were determined from ground reaction forces measured by a strain gauge forceplate. Within the same group of subjects, the maximum angle of forward lean from which a subject could recover with a single step, the ability to recover balance in response to an accelerated support surface, and the ability to recover balance after being tripped were determined.
Recovery from the three types of postural disturbances were found to be statistically independent. The postural steadiness and the stability limit variables were only weakly correlated. Postural steadiness and stability limits were not related to the maximum recoverable angle of lean. The average medial-lateral center of pressure speed during the postural steadiness test was significantly slower for those who failed to recover after tripping than for the subjects who recovered successfully. However, a logistic regression model failed to achieve statistical significance, suggesting that the difference may not be functionally important. The anterior-posterior static stability limits were significantly larger for subjects who recovered successfully than for those who failed to recover during the accelerated support surface test. Although logistic regression suggested that a reduced anterior-posterior stability limit represents a risk factor for failure to recover during this task, only nine of 28 failures could be properly classified, thus diminishing the functional importance of this finding.
Because recovery following postural disturbances could not generally be predicted from measures of postural stability, these findings suggest that these measures of postural stability are of limited utility in identifying potential anteriorly directed fallers in healthy older adults.
在健康的老年人中，确定姿势稳定性、稳定极限与从三种需要向前迈步反应的姿势干扰中恢复平衡能力之间的关系。
对健康老年人横断面样本中的多项运动任务进行分析。
一个生物力学研究实验室。
50名女性和29名65岁及以上的男性，均健康，居住在社区，参与了本研究。由老年病科医生对受试者进行检查，以确定是否存在排除因素。
通过应变片测力板测量的地面反作用力，确定安静站立（姿势稳定性）、静态倾斜（静态稳定极限）和动态摇摆（动态稳定极限）期间压力中心的前后和内外偏移距离。在同一组受试者中，确定受试者能够通过单步恢复的最大前倾角度、对加速支撑面做出反应时恢复平衡的能力以及绊倒后恢复平衡的能力。
发现从三种姿势干扰中恢复的情况在统计学上是独立的。姿势稳定性和稳定极限变量仅呈弱相关。姿势稳定性和稳定极限与最大可恢复前倾角度无关。在绊倒后未能恢复的受试者中，姿势稳定性测试期间平均内外压力中心速度明显慢于成功恢复的受试者。然而，逻辑回归模型未达到统计学显著性，表明这种差异可能在功能上并不重要。在加速支撑面测试中，成功恢复的受试者的前后静态稳定极限明显大于未能恢复的受试者。尽管逻辑回归表明前后稳定极限降低是该任务中未能恢复的危险因素，但在28例未恢复的情况中，只有9例能够被正确分类，因此削弱了这一发现的功能重要性。
由于姿势干扰后的恢复情况通常无法从姿势稳定性测量中预测，这些发现表明，这些姿势稳定性测量在识别健康老年人中潜在的向前跌倒者方面效用有限。
