Neuromuscular disorders are a group of diseases which can result in severe development disorders. They can be demonstrated by many different symptoms. The case report presents the history of a patient who reported pain in the lower limbs and muscle weakness that made it difficult to move. Result of the EMG examination revealed neurogenic changes, suggesting the possibility of suffering from a motor variant of chronic inflammatory demyelinating polyradiculoneuropathy (CIDP), although not all the symptoms presented by the patient were characteristic. During subsequent hospitalizations, skin changes were noticed in the form of heliotropic erythema, which, based on a number of additional tests, finally led to the diagnosis of juvenile dermatomyositis. The occurrence of a neurological mask in the course of juvenile dermatomyositis indicates the need for a wide differential diagnosis.