Duchenne Muscular Dystrophy
Definition - One of nine types of muscular dystrophy, a group of genetic, degenerative diseases primarily affecting voluntary muscles.
Progression - DMD eventually affects all voluntary muscles, and the heart and breathing muscles.
Duchenne muscular dystrophy is an inherited disorder that involves rapidly worsening muscle weakness.
Duchenne muscular dystrophy is a rapidly-worsening form of muscular dystrophy. Other muscular dystrophies (including Becker's muscular dystrophy) get worse much more slowly.
Duchenne muscular dystrophy is caused by a defective gene for dystrophin (a protein in the muscles). Duchenne muscular dystrophy occurs in approximately 1 out of every 3,600 male infants.
Rapidly worsening weakness
Progressive difficulty walking
Abnormal heart muscle (cardiomyopathy)
Loss of muscle mass (wasting)
Muscle contractures in the heels, legs
Readmore here http://www.nlm.nih.gov/medlineplus/ency/article/000705.htm