Inclusion Criteria:  Marfan disease according to the Ghent criteria revised in 2010 Patients followed at the CNMR in Bichat Adults ≥18 years old and ≤ 55 years old (to limit the incidence of degenerative lumbar pathologies) Patient not opposing the research Mastery of the French language  Exclusion Criteria:  History of lumbar surgery <1 year Specific pathologies of the spine (tumor, infection, trauma, fracture, inflammatory rheumatism) Inability to write, read or speak French Cognitive or behavioral problems making assessment impossible Patients receiving AME Patients under tutorship or curatorship