What Is Muscular Dystrophy?
Muscular dystrophy is a genetic disorder of the muscles in which the muscles break down and are replaced by fatty deposits. There are many types of muscular dystrophy, with variations in the muscle groups and other body systems that are affected, onset age, progression rate and inheritance pattern. To receive the appropriate diagnosis and follow-up care, it is helpful to see an experienced neurologist.
The nine forms of muscular dystrophy include:
- Becker: Becker progresses slowly. The age of onset is adolescence to early adulthood, and life expectancy is middle age.
- Congenital: Onset occurs at birth and causes all-over muscle weakness and some joint deformities. The disease is slow-progressing and shortens lifespan.
- Duchenne: Onset occurs in early childhood and is faster progressing than Becker muscular dystrophy. It affects the upper legs, upper arms and pelvis. Life expectancy is usually in the 20s.
- Distal: Onset typically occurs in 40s to 60s. This form affects the lower legs, forearms and hands. It is slow-progressing and rarely leads to total loss of function.
- Emery-Dreifuss: Onset occurs in childhood to early teens and often affects the shin, upper arm and shoulder muscles, and leads to joint deformities. The disease is slow-progressing and can increase risk of death from cardiac issues.
- Facioscapulohumeral: Onset typically occurs in childhood to early adulthood and affects muscles in the face, shoulders and upper arms. The disease is mostly slow-progressing with periods of rapid progression and survival can be decades after onset.
- Limb-Girdle: Onset typically occurs in late childhood to middle age and affects the pelvic and shoulder girdles. The disease is slow-progressing and the cause of death is often related to cardiopulmonary issues.
- Myotonic: Onset typically occurs in 20s to 40s and affects the face, neck, hands and feet first, then all muscles. Progression can last 50 to 60 years.
- Oculopharyngeal: Onset occurs in 40s to 70s and typically affects the eyelid and throat muscles. This form of the disease is slow-progressing.
Many types of muscular dystrophy cause symptoms in other body systems as well, including the:
- Endocrine system
- Gastrointestinal system
- Nervous system