The fourteen cases of Hirayama disease (HD) are presented in this article. HD is seldom disease characterized by juvenile muscular atrophy of upper extremities and benign course. All cases were diagnosed in the Research Center of Neurology (Moscow, Russia) during the year 2015-2017. Such methods as MRI (magnetic resonance imaging), EMG (electromyography), and NCS (nerve conduction studies) have been used to confirm diagnosis of HD. Transcranial magnetic stimulation was used to exclude upper motor neuron involvement in two cases. The original scale of neurological disturbances in HD has been proposed by authors to reveal correlations of HD severity with age of patients and duration of disease.Most of patients with HD are young males with common clinical signs. Detected MRI and EMG data were also comparable with previous publications. Independence of HD severity from age and duration of the disease may be the result of individual physical characteristics of dura mater and other structures of the cervical vertebra. In some our cases, amyotrophic lateral sclerosis and other neurological disorders were misdiagnosed before. In view of different prognosis in these pathologies and possible correction of HD, early diagnosis is very important.
Keywords: Arm flaccid paresis; Cervical myelopathy; Hirayama disease; Monomyelic amyotrophy; Motor focal amyotrophy; Motor neuron disease.