Bonora Gianluca, Carpinella Ilaria, Cattaneo Davide, Chiari Lorenzo, Ferrarin Maurizio
Biomedical Technology Department, Found. Don C. Gnocchi Onlus, IRCCS, Via Capecelatro 66, 20148, Milan, Italy.
LaRiCe: Gait and Balance Disorders Laboratory, Department of Neurorehabilitation, Found. Don C. Gnocchi Onlus, IRCCS, Via Capecelatro 66, 20148, Milan, Italy.
J Neuroeng Rehabil. 2015 May 5;12:45. doi: 10.1186/s12984-015-0038-0.
Step climbing is a demanding task required for personal autonomy in daily living. Anticipatory Postural Adjustments (APAs) preceding gait initiation have been widely investigated revealing to be hypometric in Parkinson's disease (PD) with consequences in movement initiation. However, only few studies focused on APAs prior to step climbing. In this work, a novel method based on wearable inertial sensors for the analysis of APAs preceding gait initiation and step climbing was developed to further understand dynamic balance control. Validity and sensitivity of the method have been evaluated.
Eleven PD and 20 healthy subjects were asked to perform two transitional tasks from quiet standing to level walking, and to step climbing respectively. All the participants wore two inertial sensors, placed on the trunk (L2-L4) and laterally on the shank. In addition, a validation group composed of healthy subjects and 5 PD patients performed the tasks on two force platforms. Correlation between parameters from wearable sensors and force platforms was evaluated. Temporal parameters and trunk acceleration from PD and healthy subjects were analyzed.
Significant correlation was found for the validation group between temporal parameters extracted from wearable sensors and force platforms and between medio-lateral component of trunk acceleration and correspondent COP displacement. These results support the validity of the method for evaluating APAs prior to both gait initiation and step climbing. Comparison between PD subjects and a subgroup of healthy controls confirms a reduction in PD of the medio-lateral acceleration of the trunk during the imbalance phase in the gait initiation task and shows similar trends during the imbalance and unloading phase of the step climbing task. Interestingly, PD subjects presented difficulties in adapting the medio-lateral amplitude of the imbalance phase to the specific task needs.
Validity of the method was confirmed by the significant correlation between parameters extracted from wearable sensors and force platforms. Sensitivity was proved by the capability to discriminate PD subjects from healthy controls. Our findings support the applicability of the method to subjects of different age. This method could be a possible valid instrument for a better understanding of feed-forward anticipatory strategies.
爬楼梯是日常生活中实现个人自主所需的一项具有挑战性的任务。步态起始前的预期姿势调整（APAs）已得到广泛研究，结果显示帕金森病（PD）患者的预期姿势调整不足，这对运动起始产生了影响。然而，仅有少数研究关注爬楼梯前的预期姿势调整。在本研究中，我们开发了一种基于可穿戴惯性传感器的新方法，用于分析步态起始和爬楼梯前的预期姿势调整，以进一步了解动态平衡控制。我们评估了该方法的有效性和敏感性。
11名帕金森病患者和20名健康受试者被要求分别执行两项从安静站立到平地行走以及爬楼梯的过渡任务。所有参与者均佩戴两个惯性传感器，分别置于躯干（L2 - L4）和小腿外侧。此外，一个由健康受试者和5名帕金森病患者组成的验证组在两个测力平台上执行这些任务。评估了可穿戴传感器参数与测力平台参数之间的相关性。分析了帕金森病患者和健康受试者的时间参数及躯干加速度。
验证组中，从可穿戴传感器和测力平台提取的时间参数之间，以及躯干加速度的中外侧分量与相应的中心压力（COP）位移之间存在显著相关性。这些结果支持了该方法在评估步态起始和爬楼梯前预期姿势调整方面的有效性。帕金森病患者与健康对照亚组之间的比较证实，在步态起始任务的失衡阶段，帕金森病患者躯干的中外侧加速度降低，并且在爬楼梯任务 的失衡和卸载阶段呈现相似趋势。有趣的是，帕金森病患者在使失衡阶段的中外侧幅度适应特定任务需求方面存在困难。
可穿戴传感器参数与测力平台参数之间的显著相关性证实了该方法的有效性。能够区分帕金森病患者和健康对照证明了该方法的敏感性。我们的研究结果支持该方法适用于不同年龄的受试者。此方法可能是更好理解前馈预期策略的一种有效工具。
