Kerrigan D C, Karvosky M E, Riley P O
Department of Physical Medicine and Rehabilitation, Harvard Medical School, Boston, Massachusetts 02114, USA.
Am J Phys Med Rehabil. 2001 Apr;80(4):244-9. doi: 10.1097/00002060-200104000-00002.
The authors previously suggested that spastic paretic stiff-legged gait, defined as reduced knee flexion in swing associated with upper-motor neuron injury, can be attributed to multiple impairments besides spastic quadriceps activity. This study hypothesizes that subjects with spastic paretic stiff-legged gait have altered kinetics not only about the knee but also about the hip and ankle.
Joint kinetic data of 20 subjects with spastic paretic stiff-legged gait caused by stroke were compared with data obtained from 20 able-bodied subjects.
Significant reductions in the subject group were found in both peak knee-joint power absorption (0.42+/-0.34 vs. 0.99+/-0.27 W/(kg x m x m/sec)) and peak ankle-joint power generation (0.74+/-0.42 vs. 1.51+/-0.17 W/(kg x m x m/sec); both P < 0.0001). The authors observed increases in peak external-hip flexion torque in stance, hip-power generation in loading response, knee-extension torque in midstance, ankle-dorsiflexion torque, and ankle-power absorption in stance. There was substantial variability in most torque and power values among subjects, which was significantly greater than that observed in the control subjects.
These findings, in conjunction with previous studies, support the likelihood of multiple mechanisms for reduced knee flexion in swing. Alternatively, some of the joint kinetic differences could be compensations for or associated with reduced knee flexion in swing. The substantial variability among subjects implies that despite a similar visual appearance of reduced knee flexion among subjects with a spastic paretic stiff-legged gait pattern, each individual has unique mechanisms associated with this observed gait pattern.
作者之前提出，痉挛性轻瘫僵硬腿步态（定义为与上运动神经元损伤相关的摆动期膝关节屈曲减少），除了痉挛性股四头肌活动外，还可归因于多种损伤。本研究假设，患有痉挛性轻瘫僵硬腿步态的受试者不仅膝关节的动力学发生改变，髋关节和踝关节的动力学也发生改变。
将20名因中风导致痉挛性轻瘫僵硬腿步态的受试者的关节动力学数据与20名健康受试者的数据进行比较。
研究组的膝关节峰值功率吸收（0.42±0.34 vs. 0.99±0.27 W/(kg·m·m/sec)）和踝关节峰值功率产生（0.74±0.42 vs. 1.51±0.17 W/(kg·m·m/sec)；均P < 0.0001）均显著降低。作者观察到站立期髋关节峰值外展屈曲扭矩、负荷反应期髋关节功率产生、站立中期膝关节伸展扭矩、踝关节背屈扭矩以及站立期踝关节功率吸收增加。受试者之间大多数扭矩和功率值存在很大差异，且显著大于对照组受试者观察到的差异。
这些发现与之前的研究一起，支持摆动期膝关节屈曲减少存在多种机制的可能性。或者，一些关节动力学差异可能是对摆动期膝关节屈曲减少的代偿或与之相关。受试者之间的巨大差异意味着，尽管患有痉挛性轻瘫僵硬腿步态模式的受试者在视觉上膝关节屈曲减少的表现相似，但每个个体都有与这种观察到的步态模式相关的独特机制。
