[The stiff-man syndrome. A case report with regard to clinical, electromyographical and pharmacological signs (author's transl)].

Our electromyographical findings show no evidence for a spinal or neurogenic origin of muscle stiffness in stiff-man syndrome. It is assumed that the tonic muscle rigidity is induced by abnormal impulses from the brainstem. The measured latencies of electrically induced muscle spasm in the legs are in accordance with this hypothetic site of origin. Muscle stiffness and spasm are decreased by the GABA derivative Baclofen as well as by Clonacepam, which is preferable to Diazepam because of less intense sedation. Spasms are increased by Chlorimipramine which may by used as a provocative test in uncertain cases. These pharmacological influences suggest an imbalance between a gabaminergic inhibitory and a noradrenergic and/or serotoninergic excitatory neuronal system.