Nadeau Stephen E
Geriatric Research, Education and Clinical Center, Malcom Randall Veterans Administration Medical Center, Gainesville, Fla. 32608-1197, USA.
Eur Neurol. 2007;58(3):142-5. doi: 10.1159/000104714. Epub 2007 Jun 29.
BACKGROUND/AIMS: Gait apraxia characterized primarily by gait ignition failure has been linked to lesions involving the dorsomedial frontal lobes, but the precise locus within this general region has not been determined. It has previously been hypothesized by Thompson and Marsden that disease, disconnection, or dysfunction of supplementary motor area (SMA) may account for the similarities in the gait disorders observed in Binswanger's disease, hydrocephalus, frontal lobe lesions, and Parkinson's disease. We reevaluate this hypothesis.
Clinical description and MRI of 2 subjects with gait apraxia characterized primarily by gait ignition failure.
Both subjects had incapacitating gait disorders characterized by particular difficulty with initiating gait and making turns. Both had MRI-demonstrated lesions of the SMA region, parasagittal convexity premotor cortex, or subjacent white matter bilaterally, one due to primary CNS lymphoma, one due to a lobar atrophy.
In both these cases, the lesions were substantially more limited and focal than any reported heretofore in the literature on gait apraxia or freezing of gait. The clinicopathologic correlation in these cases provides partial support for the Thompson and Marsden hypothesis, but also may implicate parasagittal convexity premotor cortex in the genesis of gait apraxia.
背景/目的：主要以步态启动失败为特征的步态失用症与涉及背内侧额叶的病变有关，但在这个大致区域内的确切位置尚未确定。汤普森和马斯登此前曾推测，辅助运动区（SMA）的疾病、连接中断或功能障碍可能是宾斯旺格病、脑积水、额叶病变和帕金森病中观察到的步态障碍相似性的原因。我们重新评估这一假设。
对2例主要以步态启动失败为特征的步态失用症患者进行临床描述和MRI检查。
两名患者均患有致残性步态障碍，其特征为启动步态和转弯特别困难。两人的MRI均显示SMA区域、矢状旁凸面运动前皮质或双侧相邻白质有病变，一例因原发性中枢神经系统淋巴瘤，一例因叶萎缩。
在这两个病例中，病变比以往文献中报道的任何步态失用症或步态冻结病例都更局限和更具局灶性。这些病例中的临床病理相关性为汤普森和马斯登的假设提供了部分支持，但也可能表明矢状旁凸面运动前皮质与步态失用症的发生有关。
