Electromyographical Studies on Activity of Spinal Motorneurone (about Rigidity and Tremor) Part 3. Rigidity, tremor, and athetosis in blocking of small fibre

Incomplete procaine anesthesia which is descrived by K. Fuku were applied to the posterior tibial nerve in order to paralyse the gamma efferent fibers. There was no differece observed on the rhythm and the waves form of parkinsonian tremor and motor power on voluntary contractions although rigidity of the calf muscles was decreased or abolished after the injection. This suggests that the tremor and the rigidity seen in parkinsonian syndrome is based on different mechanism. These result may indicate muscle rigidity of parkinsonian syndrome does not depend on hyperactive alpha motor neurone excitability but on hyperactivity of the gamma system.