Department of Mechanical Engineering, University of Washington, Seattle, Washington, United States of America.
College of Medicine - Phoenix, University of Arizona, Phoenix, Arizona, United States of America.
PLoS One. 2024 Nov 18;19(11):e0313617. doi: 10.1371/journal.pone.0313617. eCollection 2024.
There is growing interest in the use of biofeedback-augmented gait training in cerebral palsy (CP). Audiovisual, sensorimotor, and immersive biofeedback paradigms are commonly used to elicit short-term gait improvements; however, outcomes remain variable. Because biofeedback training requires that individuals have the capacity to both adapt their gait in response to feedback and retain improvements across sessions, changes in either capacity may affect outcomes. Yet, neither has been explored extensively in CP.
In this study, we evaluated the extent to which adolescents with CP (7M/1F; 14 years (12.5,15.26)) could adapt gait and retain improvements across four, 20-minute sessions using combined audiovisual and sensorimotor biofeedback. Both systems were designed to target plantarflexor activity. Audiovisual biofeedback displayed real-time soleus activity and sensorimotor biofeedback was provided using a bilateral resistive ankle exoskeleton. We quantified the time-course of change in muscle activity within and across sessions and overground walking function before and after the four sessions.
All individuals were able to significantly increase soleus activity from baseline using multimodal biofeedback (p < 0.031) but demonstrated heterogeneous adaptation strategies. In-session soleus adaptation had a moderate positive correlation with short-term retention of the adapted gait patterns (0.40 ≤ ρ ≤ 0.81), but generally weak correlations with baseline walking function (GMFCS Level) and motor control complexity (ρ ≤ 0.43). The latter indicates that adaptation capacity may be a critical and unique metric underlying response to biofeedback. Notably, in-session gains did not correspond to significant improvements in overground walking function (p > 0.11).
This work suggests that individuals with CP have the capacity to adapt their gait using biofeedback, but responses are highly variable. Characterizing the factors driving adaptation to biofeedback may be a promising avenue to understand the heterogeneity of existing biofeedback training outcomes and inform future system optimization for integration into clinical care.
在脑瘫（CP）中使用生物反馈增强步态训练越来越受到关注。视听、感觉运动和沉浸式生物反馈范式常用于引发短期步态改善；然而，结果仍然各不相同。因为生物反馈训练要求个体有能力根据反馈来调整步态并在各个会话中保持改善，所以任何一种能力的变化都可能影响结果。然而，在 CP 中，这两个方面都没有得到广泛的研究。
在这项研究中，我们评估了 7 名男性和 1 名女性（14 岁（12.5、15.26））青少年脑瘫患者在四个 20 分钟的会话中使用视听和感觉运动相结合的生物反馈来调整步态和保留改善的程度。这两个系统都旨在针对跖屈肌的活动。视听生物反馈显示实时比目鱼肌活动，而感觉运动生物反馈是通过双侧抗阻踝关节外骨骼提供的。我们在会话内和会话间量化了肌肉活动的时间过程以及在四个会话前后的地面行走功能的变化。
所有个体都能够使用多模态生物反馈显著增加基线时的比目鱼肌活动（p < 0.031），但表现出异质的适应策略。会话内比目鱼肌的适应与短期保留适应步态模式的能力有中等正相关（0.40 ≤ ρ ≤ 0.81），但与基线行走功能（GMFCS 水平）和运动控制复杂性的相关性较弱（ρ ≤ 0.43）。后者表明适应能力可能是对生物反馈反应的一个关键和独特的指标。值得注意的是，会话内的增益并没有对应于地面行走功能的显著改善（p > 0.11）。
这项工作表明，CP 患者有能力使用生物反馈来调整步态，但反应高度可变。描述驱动生物反馈适应的因素可能是理解现有生物反馈训练结果的异质性并为整合到临床护理中的未来系统优化提供信息的有前途的途径。
