Brunt Denis, Greenberg Brigid, Wankadia Sharmin, Trimble Mark A, Shechtman Orit
Department of Physical Therapy, University of Florida Brain Institute, Gainesville 32610, USA.
Arch Phys Med Rehabil. 2002 Jul;83(7):924-9. doi: 10.1053/apmr.2002.3324.
To determine the effect of altering the foot placement of the dominant limb in young healthy subjects and the uninvolved limb of subjects with hemiplegia on their ability to perform sit to stand (STS).
Controlled biomechanical experiment.
Research laboratory of a university health science center.
Nonrandom convenience sample of 10 healthy and 10 subjects with hemiplegia. Respective mean ages were 26 and 59 years. All patients with hemiplegia could ambulate and STS independently. The mean time since the stroke was 3.6 years.
Subjects came from a sitting to a standing position under 3 different conditions: (1) normal condition, where both limbs were placed in 100 degrees of knee flexion; (2) limb extended condition, where the dominant or uninvolved limb was extended to 75 degrees of knee flexion; and (3) limb elevated condition, where the dominant or uninvolved limb was placed on a dense foam support equal to 25% of the subject's knee height.
Vertical and anteroposterior ground reaction forces (GRFs) and bilateral tibialis anterior and quadriceps electromyogram (EMG) activity.
In the young subjects, the normally placed nondominant limb compensated for the extended or elevated position of the dominant limb. Peak GRFs and EMG amplitudes were all significantly greater for the nondominant limb. In patients with hemiplegia, the EMG of the involved limb increased 39% in the limb-elevated and -extended conditions compared with the normal condition. Respective values for the uninvolved limb decreased. GRFs were significantly greater for the uninvolved limb except for the vertical force in the limb-extended position.
Muscle activity and GRFs can be influenced by altering the initial foot placement of the dominant or uninvolved limb during STS. These initial data have positive implications for the rehabilitation of patients with hemiplegia who could be taught to overcome a reduced ability to use their impaired limb after stroke.
确定改变年轻健康受试者优势肢体以及偏瘫受试者健侧肢体的足部位置对其坐立位转换（STS）能力的影响。
对照生物力学实验。
大学健康科学中心的研究实验室。
10名健康受试者和10名偏瘫受试者的非随机便利样本。各自的平均年龄分别为26岁和59岁。所有偏瘫患者均能独立行走和进行坐立位转换。中风后的平均时间为3.6年。
受试者在3种不同条件下从坐位转换为站立位：（1）正常条件，双下肢膝关节均屈曲100度；（2）肢体伸展条件，优势或健侧肢体伸展至膝关节屈曲75度；（3）肢体抬高条件，优势或健侧肢体置于相当于受试者膝关节高度25%的致密泡沫支撑物上。
垂直和前后方向的地面反作用力（GRFs）以及双侧胫前肌和股四头肌的肌电图（EMG）活动。
在年轻受试者中，正常放置的非优势肢体补偿了优势肢体的伸展或抬高位置。非优势肢体的GRF峰值和EMG振幅均显著更大。在偏瘫患者中，与正常条件相比，受累肢体在肢体抬高和伸展条件下的EMG增加了39%。健侧肢体的相应值降低。除了肢体伸展位置的垂直力外，健侧肢体的GRFs显著更大。
在坐立位转换过程中，改变优势或健侧肢体的初始足部位置可影响肌肉活动和GRFs。这些初步数据对偏瘫患者的康复具有积极意义，可教导他们克服中风后使用受损肢体能力下降的问题。
