Duchenne and Becker muscular dystrophy: Clinical features and diagnosis. National Institute of Neurological Disorders and Stroke. NINDS muscular dystrophy information page.Onset usually begins in childhood or the teenage years. People with this type of muscular dystrophy might have difficulty lifting the front part of the foot and so might trip frequently. Hip and shoulder muscles are usually affected first. Some forms progress slowly and cause only mild disability, while others progress rapidly and cause severe impairment. This type affects boys and girls and is apparent at birth or before age 2. Onset usually occurs in the teenage years but can begin in childhood or as late as age 50. The shoulder blades might stick out like wings when arms are raised. Muscle weakness typically begins in the face, hip and shoulders. People with this form typically have long, thin faces drooping eyelids and swanlike necks. Facial and neck muscles are usually the first to be affected. This is characterized by an inability to relax muscles following contractions.
Some types of muscular dystrophy are defined by a specific feature or by where in the body symptoms begin.
