Departments of Neurology and Neurosurgery, Christian-Albrechts-University, Kiel, Germany.
Mov Disord. 2011 Apr;26(5):844-51. doi: 10.1002/mds.23583. Epub 2011 Mar 2.
The effect of subthalamic deep brain stimulation on gait coordination and freezing of gait in patients with Parkinson's disease is incompletely understood. The purpose of this study was to investigate the extent to which modulation of symmetry and coordination between legs by subthalamic deep brain stimulation alters the frequency and duration of freezing of gait in patients with Parkinson's disease. We recruited 13 post-subthalamic deep brain stimulation patients with Parkinson's disease with off freezing of gait and evaluated them in the following 4 conditions: subthalamic deep brain stimulation on (ON) and stimulation off (OFF), 50% reduction of stimulation voltage for the leg with shorter step length (worse side reduction) and for the leg with longer step length (better side reduction). Gait analysis was performed on a treadmill and recorded by an optoelectronic analysis system. We measured frequency and duration of freezing of gait episodes. Bilateral coordination of gait was assessed by the Phase Coordination Index, quantifying the ability to generate antiphase stepping. From the OFF to the ON state, freezing of gait improved in frequency (2.0 ± 0.4 to 1.4 ± 0.5 episodes) and duration (12.2 ± 2.6 to 2.6 ± 0.8 seconds; P = .005). Compared with the ON state, only better side reduction further reduced freezing of gait frequency (0.2 ± 0.2) and duration of episodes (0.2 ± 0.2 seconds; P = .03); worse side reduction did not change frequency (1.3 ± 0.4) but increased freezing of gait duration (5.2 ± 2.1 seconds). The better side reduction-associated improvements were accompanied by normalization of gait coordination, as measured by phase coordination index (16.5% ± 6.0%), which was significantly lower than in the other 3 conditions. Reduction of stimulation voltage in the side contralateral to the leg with longer step length improves frequency and duration of freezing of gait through normalization of gait symmetry and coordination in subthalamic deep brain stimulation patients with Parkinson's disease. This identifies poor leg coordination as a risk factor for causing freezing of gait.
丘脑底核脑深部电刺激对帕金森病患者步态协调和冻结步态的影响尚不完全清楚。本研究旨在探讨丘脑底核脑深部电刺激对腿部对称性和协调性的调节在多大程度上改变帕金森病患者冻结步态的频率和持续时间。我们招募了 13 名接受丘脑底核脑深部电刺激治疗后出现冻结步态的帕金森病患者，并在以下 4 种情况下对其进行评估：刺激开启（ON）和刺激关闭（OFF）、短步长（较差侧）和长步长（较好侧）腿部刺激电压降低 50%。步态分析在跑步机上进行，并通过光电分析系统记录。我们测量了冻结步态发作的频率和持续时间。通过相位协调指数评估双侧步态协调，量化产生相反步的能力。从 OFF 到 ON 状态，冻结步态的频率（从 2.0±0.4 到 1.4±0.5 次）和持续时间（从 12.2±2.6 到 2.6±0.8 秒）均有所改善（P=0.005）。与 ON 状态相比，仅较好侧降低可进一步降低冻结步态的频率（0.2±0.2）和发作持续时间（0.2±0.2 秒；P=0.03）；较差侧降低不会改变频率（1.3±0.4），但增加了冻结步态的持续时间（5.2±2.1 秒）。较好侧降低与步态协调的正常化有关，相位协调指数改善 16.5%±6.0%，明显低于其他 3 种情况。与长步长相对应的腿部刺激电压降低通过使帕金森病患者丘脑底核脑深部电刺激后的步态对称性和协调性正常化，改善了冻结步态的频率和持续时间。这表明腿部协调不良是导致冻结步态的一个危险因素。
