Facilitation of skilled finger movements by repetitive peripheral magnetic stimulation (RPMS) – a new approach in central paresis

Abstract

A new therapeutic method for the rehabilitation of central paresis of the upper extremity, especially of fine skilled finger movements, is presented. The therapeutic concept is the activation of reorganization processes in the CNS. These processes are elicited by the induction of proprioceptive input to the CNS which corresponds physiologically to the lost input during active movements. The input is generated by repetitive peripheral magnetic stimulation (RPMS) at the innervation zone of the paretic muscles. The stimulation leads to a motion of the activated muscles. The proprioceptive input is generated by two mechanisms: adequately by activation of mechanoreceptors of the stimulated muscles during the induced contractions and relaxations and inadequately by direct activation of the involved sensorimotor afferents. The method has been applied to 52 patients suffering from spastic paresis of the upper extremity. A simple clinical quantification using the Ashworth scale revealed that spasticity could be remarkably (1-2 points) reduced already by one session of RPMS lasting 15 minutes. In order to get an objective insight into the improvement of active motor performances, a neurophysiological investigation of active finger extensions was performed in eight patients suffering from a central hemiparesis. Following RPMS of the paretic finger extensors, the patients could perform rapid finger extensions with larger displacement and velocity at diminished amounts of EMG activity.