Snapshot A 2-year-old boy presents with fatigue and difficulty with walking. The mother describes her child as “clumsy,” as he usually falls while walking. The mother also reports difficultly with climbing the stairs, which is new. The mother recalls that a relative died in his teens and also experienced muscle weakness when he was very young. On physical exam, there is weakness in the proximal muscles of the lower extremity, bilateral enlargement of the calves, and a positive Gower sign. (Duchenne muscular dystrophy) Introduction Clinical definition login to view 1 more bullet Epidemiology Incidence login to view 4 more bullets Demographics login to view 2 more bullets Etiology X-linked recessive mutation in the dystrophin gene login to view 7 more bullets Pathogenesis Normal biology login to view 5 more bullets Pathology login to view 2 more bullets Presentation Symptoms login to view 3 more bullets Physical exam login to view 7 more bullets Studies Creatine kinase login to view 1 more bullet Genetic analysis login to view 2 more bullets Muscle biopsy login to view 2 more bullets Immunostaining login to view 1 more bullet Differential Limb-girdle muscular dystrophy Spinal muscular atrophy Becker muscular dystrophy Treatment Approach to management login to view 2 more bullets Medical login to view 10 more bullets Complications Muscular login to view 1 more bullet Cardiac login to view 3 more bullets Orthopedic login to view 1 more bullet Prognosis Duchenne muscular dystrophy login to view 3 more bullets Becker muscular dystrophy login to view 1 more bullet