Among patients who will be referred for ENMG and exploration of a neuropathy, orthostatic tremor will be investigated systematically.~Main objective and primary endpoint:~To estimate the prevalence of OT with its 95% confidence interval in the population of patients defined above~Presence of OT confirmed by surface EMG (polygraphy) in patients with standing instability referred for ENMG.~Secondary objectives and end points~Determine the demographic, clinical, electrophysiological characteristics of patients with OT; Estimate the prevalence of peripheral neuropathy in patients with OT; Duration of symptoms; Correlation with quantitative neuropathy scores (ISS, MRC, ONLS, R-ODS)~Age, sex, clinical parameters: symptoms reported by the patient (instability, tremor, weakness, pain, falls), duration, current medications, ISS score, MRC score, ONLS score, R-ODS score) and electrophysiological parameters (mean frequency of OT in Hertz, MUNIX score (number of motor units in the anterior tibialis, calculated by software on the ENMG machine).
Clinical presentation of orthostatic tremor (OT) may be misleading and simply perceived by a postural instability such as in several peripheral neuropathies. In addition, peripheral neuropathies represent the leading cause of pathologies associated with OT. Among patients referred for an electroneuromyogram (ENMG) for peripheral neuropathy and presenting with postural unsteadiness, OT assessment will be systematically performed. Demographic, clinical and polygraphy characteristics of these patients will be analyzed and prevalence of OT in the general population of peripheral neuropathies will be assessed.