Tremor is a disorder which does not threaten human life but often markedly and permanently reduces its quality. With regard to the variety of causes of tremor and their different therapy the prerequsite of successful treatment is the most accurate possible assessment of its etiology.As regards the frequency of different types of tremor in the general population, the crucial issue is in particular the differentiation of incipient parkinsonian and essential tremor. While the diagnosis is easy when the syndrome is fully developed, in the initial stages of the disease it is frequently not possible to make a decision merely on the basis of the clinical picture. So far a generally accepted method for diferentiation of the mentioned types of tremor is lacking. A method which could be of significant assistance in the differential diagnosis is Weight-loaded polymyography of the muscles of the upper extremities. In 1995–1999 in the Movemed disorders center at the 1st Department of Neurology of the Medical Faculty in Brno by this method a total of 46 patients were examined who suffered from tremor of the upper extremities. The working diagnosis and result of the polymyographic examination were compared with the final diagnosis done on the basis of the polymyographic finding, therapeutic test and further follow up of the clinical picture. The sensitivity of the polymyographic examination were 73.8 % in total, and for different types of tremor as follows: 100 % for parkinsonian tremor, 95.6 % for essential tremor as compared with the sensitivity of clinical examination alone: 40.5 % total, 57 % parkinsonian, 46.4 % essential tremor, the specificity being 54.8 % for the total, 57 % parkinsonian, 61.9 % essential tremor. Polymyographic examination has a relatively high sensitivity and specificity for both types of tremor and is of fundamental importance in the differential diagnosis of incipient stages of parkinsonian and essential tremor.

        Key words: tremor, polymyographic examination, differential diagnosis