Schenck Christopher, Kesar Trisha M
Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA, USA.
Division of Physical Therapy, Department of Rehabilitation Medicine, Emory University, 1441 Clifton Rd NE, Atlanta, GA, 30322, USA.
J Neuroeng Rehabil. 2017 Jun 6;14(1):52. doi: 10.1186/s12984-017-0252-z.
In individuals with post-stroke hemiparesis, reduced push-off force generation in the paretic leg negatively impacts walking function. Gait training interventions that increase paretic push-off can improve walking function in individuals with neurologic impairment. During normal locomotion, push-off forces are modulated with variations in gait speed and slope. However, it is unknown whether able-bodied individuals can selectively modulate push-off forces from one leg in response to biofeedback. Here, in a group of young, neurologically-unimpaired individuals, we determined the effects of a real-time visual and auditory biofeedback gait training paradigm aimed at unilaterally increasing anteriorly-directed ground reaction force (AGRF) in the targeted leg.
Ground reaction force data during were collected from 7 able-bodied individuals as they walked at a self-selected pace on a dual-belt treadmill instrumented with force platforms. During 11-min of gait training, study participants were provided real-time AGRF biofeedback encouraging a 20-30% increase in peak AGRF generated by their right (targeted) leg compared to their baseline (pre-training) AGRF. AGRF data were collected before, during, and after the biofeedback training period, as well as during two retention tests performed without biofeedback and after standing breaks.
Compared to AGRFs generated during the pre-training gait trials, participants demonstrated a significantly greater AGRF in the targeted leg during and immediately after training, indicating that biofeedback training was successful at inducing increased AGRF production in the targeted leg. Additionally, participants continued to demonstrate greater AGRF production in the targeted leg after two standing breaks, showing short-term recall of the gait pattern learned during the biofeedback training. No significant effects of training were observed on the AGRF in the non-targeted limb, showing the specificity of the effects of biofeedback toward the targeted limb.
These results demonstrate the short-term effects of using unilateral AGRF biofeedback to target propulsion in a specific leg, which may have utility as a training tool for individuals with gait deficits such as post-stroke hemiparesis. Future studies are needed to investigate the effects of real-time AGRF biofeedback as a gait training tool in neurologically-impaired individuals.
在中风后偏瘫患者中，患侧下肢蹬离力产生减少对步行功能产生负面影响。增加患侧蹬离力的步态训练干预可改善神经功能受损个体的步行功能。在正常行走过程中，蹬离力会随着步态速度和坡度的变化而调节。然而，尚不清楚身体健全的个体是否能够根据生物反馈选择性地调节单腿的蹬离力。在此，在一组年轻、神经功能正常的个体中，我们确定了一种实时视觉和听觉生物反馈步态训练范式的效果，该范式旨在单侧增加目标腿向前的地面反作用力（AGRF）。
在配备力平台的双带跑步机上，以自选速度行走时，收集了7名身体健全个体的地面反作用力数据。在11分钟的步态训练期间，研究参与者获得实时AGRF生物反馈，鼓励其右侧（目标）腿产生的峰值AGRF比基线（训练前）AGRF增加20%-30%。在生物反馈训练期之前、期间和之后，以及在无生物反馈和站立休息后进行的两次保持测试期间，收集AGRF数据。
与训练前步态试验期间产生的AGRF相比，参与者在训练期间和训练后立即在目标腿上表现出显著更大的AGRF，表明生物反馈训练成功诱导了目标腿上AGRF产生增加。此外，在两次站立休息后，参与者在目标腿上仍表现出更大的AGRF产生，显示出对生物反馈训练期间所学步态模式的短期记忆。未观察到训练对非目标肢体的AGRF有显著影响，表明生物反馈对目标肢体影响的特异性。
这些结果证明了使用单侧AGRF生物反馈来针对特定腿部推进的短期效果，这可能作为一种训练工具用于中风后偏瘫等步态缺陷个体。未来需要研究实时AGRF生物反馈作为神经功能受损个体步态训练工具的效果。
