Quantification of Nerve Stiffness in Neuropathies

Inclusion Criteria: * Male or female aged 18 to 65 * Having social insurance status * Having given informed consent * Diagnostic of chronic inflammatory demyelinating polyradiculoneuropathy (CIDP), CMT1a or Anti-MAG (peak immunoglobulin M (IGm)\>15,000 BTU) Exclusion Criteria: For controls: * Person staying in a health or social facility * Person unable to understand the protocol and to respect the modalities * Person deprived of liberty * Person of legal age benefiting from a system of legal protection (guardianship, curators or safeguard of justice) * Participation in another biomedical research in progress * Diabetes, history of neuromuscular disease For CIDP: * Person staying in a health or social facility * Person unable to understand the protocol and to respect the modalities * Person deprived of liberty * Person of legal age benefiting from a system of legal protection (guardianship, curators or safeguard of justice) * Participation in another biomedical research in progress * MRC score \< 3 For Charcot-Marie-Tooth type 1 (CMT1) and anti-MAG: * Person staying in a health or social facility * Person unable to understand the protocol and to respect the modalities * Person deprived of liberty * Person of legal age benefiting from a system of legal protection (guardianship, curators or safeguard of justice) * Participation in another biomedical research in progress