What are muscular dystrophies?
Muscular dystrophies (MD) are a group of genetic (inherited) diseases. They cause weakness and breakdown of the muscles that control movement. These disorders are progressive (get worse over time).
There are many forms of muscular dystrophy. Some are found at birth, such as congenital muscular dystrophy, and others in adolescence (teenage years), such as Becker muscular dystrophy. The three most common types of MD are:
- Duchenne MD
- Facioscapulohumeral MD
- Myotonic MD
These types are different in the way they are inherited (passed from parent to child), the age when they start, how quickly they get worse and the body parts they affect.
Duchenne MD mostly affects boys. It is caused by mutations in the gene that controls a protein called dystrophin, which helps keep muscle fibers healthy and functioning. Duchenne MD usually starts at age 3 to 5 years and progresses (gets worse) rapidly. Most boys become unable to walk at age 12 and by age 20 have to use a respirator to breathe.
Facioscapulohumeral MD appears in adolescence. It causes progressive weakness in the facial muscles and certain muscles in the arms and legs. It progresses slowly. Symptoms can vary, from mild to disabling.
Myotonic MD can start at different ages. Symptoms include:
- Myotonia (prolonged muscle spasm) in the fingers and facial muscles
- A floppy-footed, high-stepping gait (walk or run)
- Heart abnormalities
- Endocrine (hormone system) problems
People with MD have a distinct appearance, with long faces and drooping eyelids. Men with MD have frontal baldness (receding hairline).
Prognosis for people with MD
The prognosis for muscular dystrophy (MD) is different for each type of MD and how it progresses. Some people have very mild MD that progresses slowly over a normal lifespan. Other people have faster progression of muscle weakness, disability and loss of the ability to walk. People with Duchenne MD usually die in their early 20s.
At the OHSU ALS and Neuromuscular Disease Center, we provide the most advanced treatment for muscular dystrophy. We bring experts from around OHSU together to give you the best care available.