Le tremblement orthostatique, comment le reconnaître, l'explorer et le traiter

Primary orthostatic tremor (POT) is a rare condition characterized by unsteadiness and tremor when standing still that disappears on walking and sitting, with a normal neurological examination. The specific individual neurophysiological marker is a 13-18 Hz frequency tremor recorded on lower limb surface polymyography. POT is a progressive disorder with slowly increasing disability, including instability and the fear of falling. Falls are rare and if present should lead to search for an associated neurological syndrome (parkinsonian or cerebellar) in the context of an OT “plus”. POT should be distinguished from tremor in orthostatism and from orthostatic myoclonus. Clonazepam and gabapentin are proposed as first-line therapies for POT, in synergy with a psycho-behavioral approach. With early diagnosis, the psychosocial consequences of the disease can be limited.