Activities, Motor clinical trials

INTENSIVE TREATMENT WITH ROBOTIC PLUS VIBRATION IN STROKE

The Amadeo® Manual Robotic System (Tyromotion GmbH, Graz, Austria) is designed for rehabilitative treatment of the hand and fingers providing robot-assisted exercise for the finger flexors and extensors. This system has a controlled position, active, active-assisted and passive exercise mode, it also allows isometric exercises with visual feedback provided during computerized games that emphasize flexion and extension. Another of the functions that this device presents and that differentiates it from other handheld robotic systems is its vibration function. Through sensors that are placed on the fingertips, providing a vibratory proprioceptive stimulus of different frequencies. Currently, there are no published trials on the efficacy of the vibration of this device and its consequent improvement in the sensitivity and functionality of patients with hemiparesis after stroke. Investigations have been conducted in patients with peripheral lesions and in the healthy population. A preliminary study with monkeys demonstrated that the frequency of the vibration presents better results when the muscle stretch receptors are driven by a high frequency vibration, activating the neurons corresponding to the motor cortex and in the 3rd primary sensory area. More recent studies have shown the efficacy of focal vibratory stimulation applied to the wrist and forearm muscles, specifically the application to the tendon of the stimulated muscle. Regarding the most appropriate form of stimulation, the most important determining factors to highlight are the frequency of application, the duration and intensity and the time of application. The mechanism of action of local muscle vibration is to stimulate various receptors. Meissner corpuscles respond best around 40 Hz, while Vater-Pacini corpuscles around 100 Hz. Together, they are also known as rapidly adapting cutaneous receptors. In contrast, Merkel-Ranvier cells and Ruffini corpuscles are called slow-adapting and classically described as sensitive to sustained pressure. That is why authors of different studies have focused on high frequency vibration of 300 Hz, for 30 minutes. 3 times per week. The duration of vibratory stimulation, different studies show the effects of vibration and changes in the cortex after performing the treatment constantly, for about ten days, intensively three to four days a week, observing long-term changes in terms on cortical excitability.