A therapeutic approach to 'freezing' in Parkinson's disease

步态冻结被描述为帕金森-S病最令人不安、最不为人所知的症状之一。在最严重的情况下，它可以阻止患者原地踏步，使他们在S左右敦促自己行走时完全无法移动。这对病人是非常有害的吗？独立性、生活质量和健康。它经常会导致摔倒，导致骨折、住院和社会孤立。步态冻结是一个常见的问题，也是治疗的难点。帕金森-S病的常规治疗，如左旋多巴或脑深部刺激，可以取消某些患者的冷冻。然而，还有许多其他患者在治疗后仍有冰冻发作。本建议针对后一类患者，并提出了一种基于非侵入性电刺激技术的替代治疗方法。我们的假设是，冰冻是由于姿势调整失败造成的，而姿势调整必须在一只脚从地面抬起迈出一步之前发生。我们的计划是通过激活一种在帕金森S病中完好无损的反射来唤起姿势调整。这是通过通过耳朵后面的皮肤传递小电流来实现的，这会刺激内耳平衡器官的神经，导致反射性身体摇摆。身体摆动将作为替代的姿势调整，并释放腿部的步态。此外，我们应该电刺激腿部肌肉，以辅助随后的踏步运动。我们认为，这一序列的刺激将打破冻结的插曲，并允许步态周期继续下去。我们在计划中的实验室实验中获得的结果将为设计一种可以在实验室外使用的简单假肢装置提供一个起点。

Freezing of gait has been described as one of the most disturbing and least understood symptoms of Parkinson?s disease. In its severest form it can stop patients in their tracks and render them completely immobile for 10 s or so as they urge themselves to walk. It is profoundly detrimental to patients? independence, quality of life, and health. It can often be a cause of falls leading to fractures, hospitalisation and social isolation. Freezing of gait is a common problem and difficult to treat. Conventional treatments for Parkinson?s disease, such as levodopa or deep brain stimulation, can abolish freezing in some patients. However, there are many other patients for whom freezing episodes persist after treatment. The present proposal targets this latter category of patient and suggests an alternative therapeutic approach based on non-invasive electrical stimulation techniques. Our hypothesis is that freezing results from a failure of the postural adjustment that has to occur before a foot can be lifted from the ground to take a step. Our plan is to evoke the postural adjustment by activating a reflex that is intact in Parkinson?s disease. This will be done by passing a small electrical current through the skin behind the ears, which stimulates nerves from balance organs in the inner ear and causes a reflex body sway. The body sway will act as a surrogate postural adjustment and free the leg for stepping. In addition, we shall electrically stimulate leg muscles to assist the subsequent stepping movement. We suggest that this sequence of stimulation will break the freezing episode and allow the gait cycle to continue. The results we obtain in our planned laboratory-based experiments will provide a starting point for designing a simple prosthetic device that can be used outside the laboratory.