High Carleigh M, McHugh Hannah F, Mills Stephen C, Amano Shinichi, Freund Jane E, Vallabhajosula Srikant
Department of Physical Therapy Education, Elon University, Elon, NC, USA.
Department of Biomedical Engineering, University of Southern California, Los Angeles, CA, USA.
Gait Posture. 2018 Jun;63:202-207. doi: 10.1016/j.gaitpost.2018.05.010. Epub 2018 May 8.
Aging and Parkinson's disease are often associated with impaired postural control. Providing extrinsic feedback via vibrotactile sensation could supplement intrinsic feedback to maintain postural control.
We investigated the postural control response to vibrotactile feedback provided at the trunk during challenging stance conditions in older adults at high fall risk and individuals with Parkinson's disease compared to healthy older adults.
Nine older adults at high fall risk, 9 persons with Parkinson's disease and 10 healthy older adults performed 30s quiet standing on a force platform under five challenging stance conditions with eyes open/closed and standing on firm/foam surface with feet together, each with and without vibrotactile feedback. During vibrotactile feedback trials, feedback was provided when participants swayed >10% over the center of their base of support. Participants were instructed vibrations would be in response to their movement. Magnitude of postural sway was estimated using center of pressure path length, velocity, and sway area. Dynamics of individuals' postural control was evaluated using detrended fluctuation analysis.
Results showed that vibrotactile feedback induced a change in postural control dynamics among persons with Parkinson's disease when standing with intact intrinsic visual input and altered intrinsic somatosensory input, but there was no change in sway magnitude. However, use of vibrotactile feedback did not significantly alter dynamics of postural control in older adults with high risk of falling or reduce the magnitude of sway.
Considering the effects of vibrotactile feedback were dependent on the population and stance condition, designing an optimal therapeutic regimen for balance training should be carefully considered and be specific to a target population. Furthermore, our results suggest that explicit instructions on how to respond to the vibrotactile feedback could affect training outcome.
衰老和帕金森病常与姿势控制受损相关。通过振动触觉提供外在反馈可补充内在反馈以维持姿势控制。
我们研究了在具有高跌倒风险的老年人和帕金森病患者中，与健康老年人相比，在具有挑战性的站立条件下，躯干提供的振动触觉反馈对姿势控制的反应。
9名高跌倒风险的老年人、9名帕金森病患者和10名健康老年人在力平台上进行30秒安静站立，处于五种具有挑战性的站立条件下，眼睛睁开/闭合，双脚并拢站在坚实/泡沫表面，每种条件下均有和没有振动触觉反馈。在振动触觉反馈试验中，当参与者在其支撑面中心上方摇摆超过10%时提供反馈。参与者被告知振动将是对他们运动的反应。使用压力中心路径长度、速度和摇摆面积估计姿势摇摆的幅度。使用去趋势波动分析评估个体姿势控制的动态变化。
结果表明，当帕金森病患者在具有完整内在视觉输入和改变的内在体感输入的情况下站立时，振动触觉反馈会引起姿势控制动态变化，但摇摆幅度没有变化。然而，使用振动触觉反馈并没有显著改变高跌倒风险老年人的姿势控制动态，也没有减少摇摆幅度。
考虑到振动触觉反馈的效果取决于人群和站立条件，为平衡训练设计最佳治疗方案时应仔细考虑并针对目标人群进行定制。此外，我们的结果表明，关于如何响应振动触觉反馈的明确指导可能会影响训练结果。
