Yanagisawa N, Ueno E, Hayashi R, Tokuda T, Takou K
Department of Medicine, Shinshu University.
Rinsho Shinkeigaku. 1993 Dec;33(12):1310-2.
Apraxia of gait is a unique disorder of locomotion characterized by inability in lifting the feet from the floor despite alternating stepping action (frozen gait), and disequilibrium. Responsible site of lesions are in the frontal lobe and/or the basal ganglia. It is observed in an advanced stage of Parkinson's (PD) or vascular parkinsonism with multiple cerebral infarction (MCI). Studies on equilibrium and natural gait have disclosed unique features in this condition. Records of floor reaction forces in forward locomotion showed that vertical-foreaft vector angles at kick-off phase is small in both PD and MCI with frozen gait. EMG of antagonists in leg muscles were either reciprocal or coincided in frozen gait, and rhythm of stepping was crucial for development of freezing. Center of foot pressure (CFP) in forward-bent natural posture in PD still locates behind that of normals. For voluntary forward bending, maximal shift of CFP was smaller, and increase in EMG was larger in PD subjects. Pushing chest backward results in step-out or fall in parkinsonians. In this response, EMG in the pretibial muscles were the same amount in both PD and normals. However, velocity in hip extension and amount of knee and ankle displacement were smaller in PD.
步态失用是一种独特的运动障碍，其特征是尽管有交替的迈步动作（冻结步态），但仍无法将脚抬离地面，且存在平衡失调。病变的责任部位在额叶和/或基底神经节。在帕金森病（PD）或伴有多发性脑梗死的血管性帕金森综合征（MCI）的晚期可观察到这种情况。对平衡和自然步态的研究揭示了这种情况下的独特特征。向前运动时地面反作用力的记录显示，在患有冻结步态的PD和MCI患者中，起始阶段的垂直-前后向量角度都较小。在冻结步态中，腿部肌肉拮抗肌的肌电图要么是交替的，要么是一致的，并且迈步节奏对冻结的发展至关重要。在PD患者向前弯曲的自然姿势下，足底压力中心（CFP）仍位于正常人体之后。对于主动向前弯曲，PD患者CFP的最大偏移较小，肌电图的增加较大。向后推胸部会导致帕金森病患者迈出脚步或跌倒。在这种反应中，PD患者和正常人胫前肌的肌电图量相同。然而，PD患者髋关节伸展的速度以及膝关节和踝关节的位移量较小。
