The loss of ability to walk in many children with DMD (Duchenne muscular Dystrophy) is a pejorative event. Biomechanical and morphological unknowledge about the loss of the walk ability in children with DMD is an obstacle in reeducative, pharmacological or surgical therapeutic targets.

The loss of ability to walk in many children with DMD (Duchenne muscular Dystrophy) is a pejorative event. Biomechanical and morphological unknowledge about the loss of the walk ability in children with DMD is an obstacle in reeducative, pharmacological or surgical therapeutic targets. We suppose that there are muscular characteristics and predictive parameters of the loss of walk ability. The identification of these potential therapeutic targets would improve the surveillance and the clinical care but would also guide future clinical and fundamental trials too.

Inclusion Criteria:

• Young man ou woman (5 to 17 years old) with Duchenne Muscular Dystrophy (confirmed by immunohistochimy on the muscular biopsy and/or mutation in the dystrophin confirmed by molecular biology)
• Time more than 7 secondes to test of 10 m and/or distance less than 330 m to walk test of 6 minutes. These values are recent markers to include children with a strong risk of loss of walking ability in 2 years.
• Parental inform sign consent and / or child inform consent

Exclusion Criteria:

• Recent orthopaedic surgery of lower limbs (6 months)
• Other chronic disease associated, which have an impact on the walking
• Cognitive Deficiency or behavior disorders limiting the understanding of the study
• Children who can benefit ATU (translarna ® or other) during the study
• All MRI contradications : pacemaker or neurosensory stimulator or implantable defibrillator, neurosurgical valves, cochlear implant or ferromagnetic implants near nervous structures, brace, metallic prostheses, not cooperative or agitated patients, patient claustrophobic, pregnant woman.