Alberts Jay L, Hirsch Joshua R, Koop Mandy Miller, Schindler David D, Kana Daniel E, Linder Susan M, Campbell Scott, Thota Anil K
Department of Biomedical Engineering, Cleveland Clinic, OH;
Center for Neurological Restoration, Cleveland Clinic, OH;
J Athl Train. 2015 Jun;50(6):578-88. doi: 10.4085/1062-6050-50.2.01. Epub 2015 Apr 6.
Force platforms and 3-dimensional motion-capture systems provide an accurate method of quantifying postural stability. Substantial cost, space, time to administer, and need for trained personnel limit widespread use of biomechanical techniques in the assessment of postural stability in clinical or field environments.
To determine whether accelerometer and gyroscope data sampled from a consumer electronics device (iPad2) provide sufficient resolution of center-of-gravity (COG) movements to accurately quantify postural stability in healthy young people.
Controlled laboratory study.
Research laboratory in an academic medical center.
A total of 49 healthy individuals (age = 19.5 ± 3.1 years, height = 167.7 ± 13.2 cm, mass = 68.5 ± 17.5 kg).
INTERVENTION(S): Participants completed the NeuroCom Sensory Organization Test (SOT) with an iPad2 affixed at the sacral level.
MAIN OUTCOME MEASURE(S): Primary outcomes were equilibrium scores from both systems and the time series of the angular displacement of the anteroposterior COG sway during each trial. A Bland-Altman assessment for agreement was used to compare equilibrium scores produced by the NeuroCom and iPad2 devices. Limits of agreement was defined as the mean bias (NeuroCom - iPad) ± 2 standard deviations. Mean absolute percentage error and median difference between the NeuroCom and iPad2 measurements were used to evaluate how closely the real-time COG sway measured by the 2 systems tracked each other.
The limits between the 2 devices ranged from -0.5° to 0.5° in SOT condition 1 to -2.9° to 1.3° in SOT condition 5. The largest absolute value of the measurement error within the 95% confidence intervals for all conditions was 2.9°. The mean absolute percentage error analysis indicated that the iPad2 tracked NeuroCom COG with an average error ranging from 5.87% to 10.42% of the NeuroCom measurement across SOT conditions.
The iPad2 hardware provided data of sufficient precision and accuracy to quantify postural stability. Accuracy, portability, and affordability make using the iPad2 a reasonable approach for assessing postural stability in clinical and field environments.
测力平台和三维运动捕捉系统提供了一种量化姿势稳定性的准确方法。高昂的成本、空间需求、实施所需时间以及对训练有素人员的需求限制了生物力学技术在临床或现场环境中姿势稳定性评估中的广泛应用。
确定从消费电子设备（iPad2）采样的加速度计和陀螺仪数据是否能提供足够的重心（COG）运动分辨率，以准确量化健康年轻人的姿势稳定性。
对照实验室研究。
一所学术医疗中心的研究实验室。
共49名健康个体（年龄 = 19.5 ± 3.1岁，身高 = 167.7 ± 13.2厘米，体重 = 68.5 ± 17.5千克）。
参与者在骶部固定一台iPad2的情况下完成了NeuroCom感觉统合测试（SOT）。
主要结果是两个系统的平衡分数以及每次试验中前后COG摆动角位移的时间序列。采用Bland-Altman一致性评估来比较NeuroCom和iPad2设备产生的平衡分数。一致性界限定义为平均偏差（NeuroCom - iPad）± 2个标准差。NeuroCom和iPad2测量值之间的平均绝对百分比误差和中位数差异用于评估两个系统测量的实时COG摆动相互跟踪的紧密程度。
在SOT条件1下，两台设备之间的界限范围为 -0.5°至0.5°，在SOT条件5下为 -2.9°至1.3°。所有条件下95%置信区间内测量误差的最大绝对值为2.9°。平均绝对百分比误差分析表明，在整个SOT条件下，iPad2跟踪NeuroCom COG的平均误差范围为NeuroCom测量值的5.87%至10.42%。
iPad2硬件提供了足够精确和准确的数据来量化姿势稳定性。准确性、便携性和可承受性使得使用iPad2成为临床和现场环境中评估姿势稳定性的合理方法。
