Preserved gait kinematics during controlled body unloading.
Preserved gait kinematics during controlled body unloading.
复制标题
DOI：
10.1186/s12984-017-0239-9
复制
发表时间：
2017-04-04
影响因子：
5.1
通讯作者：
Bolliger M
中科院分区：
文献类型：
--
作者：
Awai L;Franz M;Easthope CS;Vallery H;Curt A;Bolliger M
体重支持的运动训练被证明可以改善神经系统患者的行走功能，并且通常在跑步机上进行。然而，在跑步机上行走并不模仿自然行走，原因有几个：缺乏自我启动，需要较少的主动收回腿和改变传入输入。地上训练的优越性已在人类身上得到证实，并在大鼠身上得到证实，与跑步机训练相比，大鼠表现出更大的可塑性，尤其是在下行通路中。因此，我们开发了一种体重支持系统，允许不受限制的地上行走，以最小的干扰力来训练神经系统患者。本研究探讨了不同重量的支持对健康人步态的影响。运动学和肌电图数据的19名健康人记录在地上行走在不同水平的体重支持（0，10，20，30，40，和50%）。计算上半身倾斜度、下半身关节角度、多关节协调度以及时距参数。连续数据进行了分析，在所有卸载条件下的步态周期内的明显变化。时间步态参数是最敏感的变化，在身体卸载，而空间变量（步长，关节角度）表现出适度的反应时，卸载高达50%的体重。腓肠肌的激活表现出逐渐减少，而增加卸载股二头肌肌肉表现出增加的活动水平在50%卸载。这些变化发生在站立阶段，而摆动阶段的活动保持不变。健康的人能够保持他们的步行运动学惊人的恒定，即使卸载了一半的体重，这表明重量支持系统允许生理步态模式。然而，保持一个给定的步行速度使用接近正常的运动学，而被卸载是通过适应肌肉活动模式。有趣的是，保持速度所需的推进力并不是通过在蹬离时增加腓肠肌活动来实现的，而是通过在站立阶段收回腿时提高股二头肌活动来实现的。它仍然是有待调查的程度神经系统患者步态障碍，能够适应他们的步态模式，以响应身体卸载。
Body weight supported locomotor training was shown to improve walking function in neurological patients and is often performed on a treadmill. However, walking on a treadmill does not mimic natural walking for several reasons: absent self-initiation, less active retraction of leg required and altered afferent input. The superiority of overground training has been suggested in humans and was shown in rats demonstrating greater plasticity especially in descending pathways compared to treadmill training. We therefore developed a body weight support system allowing unrestricted overground walking with minimal interfering forces to train neurological patients. The present study investigated the influence of different amounts of body weight support on gait in healthy individuals. Kinematic and electromyographic data of 19 healthy individuals were recorded during overground walking at different levels of body weight support (0, 10, 20, 30, 40, and 50%). Upper body inclination, lower body joint angles and multi-joint coordination as well as time-distance parameters were calculated. Continuous data were analyzed with regard to distinct changes within a gait cycle across all unloading conditions. Temporal gait parameters were most sensitive to changes in body unloading while spatial variables (step length, joint angles) showed modest responses when unloaded by as much as 50% body weight. The activation of the gastrocnemius muscle showed a gradual decrease with increasing unloading while the biceps femoris muscle showed increased activity levels at 50% unloading. These changes occurred during stance phase while swing phase activity remained unaltered. Healthy individuals were able to keep their walking kinematics strikingly constant even when unloaded by half of their body weight, suggesting that the weight support system permits a physiological gait pattern. However, maintaining a given walking speed using close-to-normal kinematics while being unloaded was achieved by adapting muscle activity patterns. Interestingly, the required propulsion to maintain speed was not achieved by means of increased gastrocnemius activity at push-off, but rather through elevated biceps femoris activity while retracting the leg during stance phase. It remains to be investigated to what extent neurological patients with gait disorders are able to adapt their gait pattern in response to body unloading.