[Propriospinal myoclonus induced by relaxation and drowsiness].

Propriospinal myoclonus is a subtype of spinal myoclonus characterized by axial flexion or extension jerks, arrhythmic and prolonged muscle bursts with a pattern of activation consistent with a slow conduction within the propriospinal pathways. We describe a new idiopathic case of flexion propriospinal myoclonus occurring upon relaxation and drowsiness. This syndrome is to be added to the spectrum of movement disorders occurring during drowsiness.