Hip circumduction is not a compensation for reduced knee flexion angle during gait
Hip circumduction is not a compensation for reduced knee flexion angle during gait
复制标题
DOI：
10.1016/j.jbiomech.2019.02.026
复制
发表时间：
2019-04-18
影响因子：
2.4
通讯作者：
Sulzer, James
中科院分区：
文献类型：
--
作者：
Akbas, Tunc;Prajapati, Sunil;Sulzer, James
长期以来，人们一直认为髋部外展可以补偿摆动期膝关节屈曲角度的减小，尤其是在中风后。然而，还有其他补偿性运动，例如骨盆倾斜（髋部远足），也可以用来促进脚部间隙，从而提高能量效率。我们之前的研究表明，髋部外展可能不能作为中风后膝关节屈曲减少的补偿。之前的研究在中风后僵膝步态 (SKG) 患者的预摆动过程中应用了机器人膝关节屈曲辅助，发现尽管膝关节屈曲和脚趾间隙有所改善，但外展仍增加。因此，我们的假设是髋部外展并不是膝关节屈曲减少的补偿。我们利用三个因素在未受损的个体上模拟了中风后 SKG 的运动学：减少膝关节屈曲的膝关节矫形器、中风后通常佩戴的踝足矫形器以及匹配的步态速度。我们比较了健康对照组和之前记录的中风后 SKG 人群中实验因素之间的时空测量和运动学。我们重点关注髋部和骨盆的额面运动作为可能的补偿机制。我们观察到，无论步态速度如何，与不受限制的行走（1.5 度，p < 0.01）相比，膝关节屈曲限制会增加骨盆倾斜度（2.8 度，p < 0.01），但与中风后 SKG（3A 度）相似。然而，与膝关节屈曲受限的未受损个体（4.2 度，p < 0.05）相比，中风后 SKG 患者的髋部外展程度更大（8.2 度）。这些结果表明，骨盆倾斜（而不是髋部外展）可以补偿膝关节屈曲角度的减小。因此，其他因素（可能是神经因素）促进了中风后 SKG 中观察到的髋部过度外展。 (C) 2019 Elsevier Ltd. 保留所有权利。
It has long been held that hip abduction compensates for reduced swing-phase knee flexion angle, especially in those after stroke. However, there are other compensatory motions such as pelvic obliquity (hip hiking) that could also be used to facilitate foot clearance with greater energy efficiency. Our previous work suggested that hip abduction may not be a compensation for reduced knee flexion after stroke. Previous study applied robotic knee flexion assistance in people with post-stroke Stiff-Knee Gait (SKG) during pre-swing, finding increased abduction despite improved knee flexion and toe clearance. Thus, our hypothesis was that hip abduction is not a compensation for reduced knee flexion. We simulated the kinematics of post-stroke SKG on unimpaired individuals with three factors: a knee orthosis to reduce knee flexion, an ankle-foot orthosis commonly worn by those post-stroke, and matching gait speeds. We compared spatiotemporal measures and kinematics between experimental factors within healthy controls and with a previously recorded cohort of people with post-stroke SKG. We focused on frontal plane motions of hip and pelvis as possible compensatory mechanisms. We observed that regardless of gait speed, knee flexion restriction increased pelvic obliquity (2.8 degrees, p < 0.01) compared to unrestricted walking (1.5 degrees, p < 0.01), but similar to post-stroke SKG (3A degrees). However, those with post-stroke SKG had greater hip abduction (8.2 degrees) compared to unimpaired individuals with restricted knee flexion (4.2 degrees, p < 0.05). These results show that pelvic obliquity, not hip abduction, compensates for reduced knee flexion angle. Thus, other factors, possibly neural, facilitate exaggerated hip abduction observed in post-stroke SKG. (C) 2019 Elsevier Ltd. All rights reserved.