[Immediate effects of therapeutic interventions on the central motor system and their practical consequences]

Physiotherapy and occupational therapy have changed over recent years influenced by our growing neurophysiological knowledge especially about motor learning. Understanding the direct effects of therapeutic interventions on the central motor system is crucial for further development of therapeutic approaches. Recent studies are discussed dealing with the facilitatory effects of different therapeutic interventions and the question whether or not the activation of the healthy upper limb has a facilitatory or inhibitory net-effect on the damaged central motor system. In a controlled study using transcranial magnetic stimulation (TMS) we could show that motor system excitability is not influenced by the contraction type (isometric or isotonic), neither in healthy nor in stroke patients. Two TMS-studies could show that voluntary exercises of the non-affected hand alone or in bimanual tasks do not have an inhibitory effect on the damaged central motor system. However, the strongest facilitation of the damaged motor area could be achieved by voluntary activation of the affected extremity. The therapeutic approach in severely or completely paretic upper limbs should, hence, be focussed on functional compensation. As soon as voluntary activity is obtainable intensive voluntary exercises should however be preferred, with contraction type (isometric or isotonic) seeming not to be important.