Fall Risk Assessment in a Population of Charcot-Marie-Tooth Disease Type 1A (CMT 1A) by Timed Up and Go Test

Inclusion Criteria: * Patients older than 18 years * Diagnosis of Charcot Marie Tooth disease, type 1A confirmed by molecular biology (duplication 17.p11.2) and by a pathological electromyogram, that is to say with demyelinating impairment (+/- axonal) dependent length * Listening and written French * Strength of the quadriceps superior to 2/5 MMT MRC * Agreement after written information, clear and honest about the purpose of the study, the nature of the tests and their possible side effects or bothersome * Health insurance cover Exclusion Criteria: * Presence of other neurological comorbidity * Presence of coronary artery disease unstabilized * Peripheral neuropathy of other causes: diabetes, monoclonal gammopathy, malignancy, solid cancer, systemic autoimmune disease (lupus, Sjögren's disease, Wegener sarcoidosis ...), infectious disease (viral hepatitis, HIV ...), drugs known to be responsible for iatrogenic neuropathy. * Gait trouble of other origin * Patients unable to give their consent. * Intellectual deficit that does not allow to comply with tests * Patient under guardianship, or protection of justice.