O'Sullivan Maura, Blake Catherine, Cunningham Conal, Boyle Gerard, Finucane Ciarán
Physiotherapy Department, Robert Mayne Day Hospital, St. James Hospital, Dublin 8, Ireland.
Age Ageing. 2009 May;38(3):308-13. doi: 10.1093/ageing/afp009. Epub 2009 Feb 28.
falls are a common cause of injury and decreased functional independence in the older adult. Diagnosis and treatment of fallers require tools that accurately assess physiological parameters associated with balance. Validated clinical tools include the Berg Balance Scale (BBS) and the Timed Up and Go test (TUG); however, the BBS tends to be subjective in nature, while the TUG quantifies an individuals functional impairment but requires further subjective evaluation for balance assessment. Other quantitative alternatives to date require expensive, sophisticated equipment. Measurement of the acceleration of centre of mass, with relatively inexpensive, lightweight, body-mounted accelerometers is a potential solution to this problem.
to determine (i) if accelerometry correlates with standard clinical tests (BBS and TUG), (ii) to characterise accelerometer responses to increasingly difficult challenges to balance and (iii) to characterise acceleration patterns between fallers and non-fallers.
torso accelerations were measured at the level of L3 using a tri-axial accelerometer under four conditions; standing unsupported with eyes open (EO), eyes closed (EC) and on a mat with eyes open (MAT EO) and closed (MAT EC). Older patients (n = 21, 8 males, 13 females) with a mean age of 78 (SD +/- 7.6) years who attended a day hospital were recruited for this study. Patients were identified as fallers or non-fallers based on a comprehensive falls history.
Spearman's rank correlation analysis examined the relationship between acceleration root mean square (RMS) data and the BBS while Pearson's correlation was used with TUG scores. Differences in accelerometer RMS between fallers and non-fallers and between test conditions were examined using t-test and non-parametric alternatives where appropriate.
there was a stepwise increase in accelerometer RMS with increasing task complexity, and the accelerometer was able to distinguish significantly between sway responses to all test conditions except between EO and EC (P < 0.05). Acceleration data for MAT EO were significantly and inversely correlated with BBS scores (P = -0.829, P < 0.001) and positively correlated with TUG values (r = 0.621, P < 0.01). There was a significant difference in acceleration RMS for MAT EO between fallers and non-fallers (P < 0.011).
this is the first study of its kind to show a high correlation between accelerometry, the BBS and TUG. Accelerometry could also distinguish between sway responses to differing balancing conditions and between fallers and non-fallers. Accelerometry was shown to be an efficient, quantitative alternative in the measurement of balance in older people.
跌倒在老年人中是导致受伤和功能独立性下降的常见原因。对跌倒者的诊断和治疗需要能够准确评估与平衡相关生理参数的工具。经过验证的临床工具包括伯格平衡量表（BBS）和定时起立行走测试（TUG）；然而，BBS本质上往往具有主观性，而TUG可量化个体的功能损害，但需要进一步进行主观评估以进行平衡评估。迄今为止，其他定量方法需要昂贵、复杂的设备。使用相对便宜、轻便的身体佩戴式加速度计测量质心加速度是解决此问题的一种潜在方法。
确定（i）加速度测量法与标准临床测试（BBS和TUG）是否相关，（ii）描述加速度计对日益困难的平衡挑战的反应，以及（iii）描述跌倒者和非跌倒者之间的加速度模式。
在四种情况下，使用三轴加速度计在L3水平测量躯干加速度；睁眼无支撑站立（EO）、闭眼站立（EC）以及在垫子上睁眼（MAT EO）和闭眼（MAT EC）站立。招募了21名年龄在78（标准差±7.6）岁的老年患者（8名男性，13名女性）参加日间医院的这项研究。根据全面的跌倒史将患者确定为跌倒者或非跌倒者。
使用Spearman等级相关分析检查加速度均方根（RMS）数据与BBS之间的关系，使用Pearson相关分析TUG评分。使用t检验以及在适当情况下使用非参数方法检查跌倒者与非跌倒者之间以及测试条件之间加速度计RMS的差异。
随着任务复杂性的增加，加速度计RMS呈逐步增加，并且加速度计能够显著区分对所有测试条件的摇摆反应，但EO和EC之间除外（P < 0.05）。MAT EO的加速度数据与BBS评分呈显著负相关（P = -0.829，P < 0.001），与TUG值呈正相关（r = 0.621，P < 0.01）。跌倒者与非跌倒者之间MAT EO的加速度RMS存在显著差异（P < 0.011）。
这是同类研究中首次表明加速度测量法与BBS和TUG之间存在高度相关性。加速度测量法还可以区分对不同平衡条件的摇摆反应以及跌倒者和非跌倒者。加速度测量法被证明是测量老年人平衡的一种有效、定量的替代方法。
