Muscular Dystrophy

Reviewed/Revised Feb 2023
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What is muscular dystrophy?

Muscular dystrophies are a group of disorders passed down from a parent (inherited) in which muscles waste away.

  • People with muscular dystrophy inherited abnormal genes that control muscle development and function

  • The various types of muscular dystrophy affect different muscles

  • Affected muscles are weak

  • Sometimes the heart muscle or the muscles that control breathing are weak, which can be dangerous

  • Muscular dystrophy can't be cured, but physical therapy may help relieve symptoms

Types of muscular dystrophy include:

  • Facioscapulohumeral dystrophy: the most common type of muscular dystrophy—symptoms begin between ages 7 and 20 and include weakness of the face and shoulder muscles

  • Duchenne muscular dystrophy and Becker muscular dystrophy: the next most common types and the most severe—muscle weakness develops in childhood or teen years, nearly always in boys

  • Emery-Dreifuss dystrophy: this type affects the upper arms, lower legs, and often the heart (heart problems can cause sudden death)

  • Limb-girdle dystrophy: this type affects shoulder and hip muscles

There are other muscle disorders that can cause weakness, including:

  • Congenital myopathies: a group of muscle problems that you’re born with or that show up when you’re an infant

  • Familial periodic paralysis: a rare disease that runs in families and leads to sudden attacks of weakness and paralysis (not being able to move part or all of your body)

  • Glycogen storage diseases: a group of rare diseases that run in families and lead to glycogen (a starch that comes from sugar) building up in your muscles

What causes muscular dystrophies?

Muscular dystrophies are caused by abnormal genes that are passed down from a parent. These abnormal genes affect the way muscles work.

What are the symptoms of muscular dystrophies?

Some types of muscular dystrophy cause symptoms starting in childhood. Other types cause symptoms that start later, in the teen years or adulthood.

Symptoms may include:

  • Muscle weakness

  • Paralysis (not being able to move part or all of your body)

  • Difficulty raising the arms

  • In children, a delay in learning to walk or difficulty running, jumping, or climbing stairs

How can doctors tell if I have muscular dystrophies?

Doctors suspect muscular dystrophies from your symptoms and family history. To know for sure, they'll do:

  • Blood tests

  • Muscle biopsy (doctors take a small piece of muscle to look at under a microscope)

How do doctors treat muscular dystrophies?

There is no cure. Doctors treat muscular dystrophies with:

  • Physical therapy

  • Ankle or leg braces

  • Medicine

Sometimes, people with muscular dystrophies need a pacemaker to control abnormal heart rhythms.

Where can I get more information about muscular dystrophies?

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