- Duchenne muscular dystrophy is the most common childhood form of muscular dystrophy, with symptoms beginning usually between 2 to 6 years of age in boys. Children who are affected start out by falling frequently, having trouble getting up from sitting or lying down, and may waddle when they walk. Also, the child's calf muscles appear enlarged.
The disease progresses slowly, but walking assistance will become necessary after a while, and the child will eventually require a wheelchair. As the body's muscles become progressively weaker, problems with breathing develop, leading to respiratory infections like pneumonia that are difficult to overcome. Research continues to provide insights into how to best care for individuals with Duchenne MD, and young men with the disease are now living longer than in years past, but unfortunately Duchenne MD shortens life expectancy significantly.
To learn more about the causes of Duchenne MD and research that is being done, see Genes, Dystrophin, and Duchenne MD.
- Becker muscular dystrophy is very similar to Duchenne MD except that the symptoms of Becker MD can appear later in youth, even as late as age 25, and the disease progresses more slowly than Duchenne MD.
- Congenital muscular dystrophy is actually a group of muscular dystrophies that are present at birth that may affect both boys and girls. Not all forms of congenital MD have been identified. One form that has is Fukuyama congenital MD, which causes severe weakness of the facial muscles and limbs, and may include joint contractures, mental and speech problems, and seizure disorder.
- Emery-Dreifuss muscular dystrophy is a less common form of childhood MD that affects boys. Its progression is slow, but unlike Duchenne, contractures--the shortening of muscles--may appear early on, and overall muscle weakness is less severe. Also, serious heart problems in Emery-Dreifuss MD may require a pacemaker.
- Limb-girdle muscular dystrophy begins in the teen years or early adulthood of both boys and girls. The disease causes muscle weakness that starts in the hips and moves to the shoulders and out to the arms and legs. It progresses slowly but eventually leads to difficulty walking.
- Facioscapulohumeral muscular dystrophy (FSH MD) also begins in adolescence or early adulthood of both boys and girls, but affects the muscles of the face ("facio-"), shoulder blades ("scapulo-"), and upper arms ("humeral"). The shoulders of the person affected slope forward, and he has trouble raising his arms over his head. The muscle weakness continues throughout the body as the disease progresses. FSH MD may range from very mild to severe. Many people affected remain able to walk.
- Myotonic muscular dystrophy (Steinert's disease) is the most common form of adult muscular dystrophy. It causes muscle weakness first in the face, feet, and hands, and also myotonia, the prolonged stiffening of muscles (like spasms)--a symptom unique to this type of MD. Myotonic MD also affects the central nervous system, heart, digestive tract, eyes, and endocrine glands. It progresses slowly and the amount of muscle weakness varies from mild to severe. An expectant mother with myotonic MD can give birth to an infant with a congenital form of the disease.
- Oculopharyngeal muscular dystrophy generally begins in a person's forties or fifties, with drooping eyelids being the first sign ("oculo-"), progressing to facial muscle weakness and difficulty swallowing ("pharyngeal"). Surgery can be done to reduce swallowing problems, to prevent choking and pneumonia.
- Distal muscular dystrophy is the name for a group of muscle diseases which begin in adulthood and have similar symptoms of weakness of forearms, hands, lower legs, and feet. These diseases, which have names like Welander, Markesbury-Griggs, Nonaka, and Miyoshi, are less severe and involve fewer muscles than other types of MD. Distal MDs affect both men and women.
Information for this article came from the Muscular Dystrophy Association USA.