INFLUENCE OF PHYSIOTHERAPEUTIC FACILITATION TECHNIQUES ON MOTOR EVOKED-POTENTIALS IN CENTRALLY PARETIC HAND EXTENSOR MUSCLES

In the rehabilitation of stroke patients, various facilitation techniq ues are applied to reduce weakness in centrally paretic muscles and to improve functional motor capacity. The present investigation compared the facilitatory effect of 5 different physiotherapeutic approaches o nto the centrally paretic extensor carpi radialis muscle in 30 stroke patients classified into 3 groups according to the individual degree o f paresis. In order to quantify the influence of the respective facili tation manoeuvre, single transcranial magnetic stimuli were applied be fore and during the application of cutaneous/proprioceptive stimuli, a weight bearing task, contraction of the affected and the non-affected extensor carpi radialis muscle and during proximal preinnervation on the affected side. All procedures, indeed, enhanced the frequency of o ccurrence of muscular response potentials and their amplitudes while d iminishing their response latencies. The most prominent effects were o bserved when the muscle itself was voluntarily activated. A similarly strong facilitation was obtained in the most severely affected patient s with cutaneous and proprioceptive stimuli, but such stimuli had inhi bitory effects in the healthy control group. The present study illustr ates the interaction of cortically evoked motor potentials with periph erally or centrally generated inputs, contributes to the understanding of the neurophysiological mechanisms underlying physiotherapeutic fac ilitation techniques and helps in providing rational criteria to decid e about the most appropriate facilitation method.