[Movement disorders in the elderly].

Movement disorders are frequent in the elderly, with various presentations and causes. We review the most frequent movement disorders encountered in the elderly. Their diagnosis, mainly based on clinical examination, is necessary due to their common occurrence and their impact on autonomy. Tremor is the most frequent movement disorder, including essential tremor and Parkinson's disease. Iatrogenic or metabolic causes should always be explored in case of any movement disorder. Many treatments can induce movement disorders, especially in the elderly, often heavily treated by medications in patients with impaired renal or/and hepatic function. Other causes of movement disorders that may be encountered in the elderly and their treatment are described. Treatment will be started according to the ratio between the benefit of the functional gain and iatrogenic risk in these frailed subjects.