Types of Muscular Dystrophy and Neuromuscular Diseases

What are the types of muscular dystrophy?

Neuromuscular disorders are conditions that affect the nerve, muscle, or neuromuscular junction (where the nerve talks to the muscle). Muscular dystrophy is a group of inherited diseases that causes weakness. They also cause wasting away of muscle tissue. There are multiple types of muscular dystrophy. Each type leads to loss of strength, increasing disability, and possible deformity.

The most common muscular dystrophy is Duchenne muscular dystrophy. The next most common is Becker muscular dystrophy.

Listed below are nine major types of muscular dystrophy. Each type differs in the muscles affected, the age of onset, and its rate of progression. The following are named for the affected muscles:

Type	Age at onset	Symptoms, rate of progression, and life expectancy
Becker	Teen to early adulthood	Symptoms are almost the same as Duchenne, but less severe. It progresses more slowly than Duchenne. Survival goes into middle age. Becker disease is almost always limited to males. This is the same as with Duchenne.
Congenital	Birth	Symptoms include general muscle weakness and possible joint deformities. The disease progresses slowly. It causes a shortened life span.
Duchenne	Ages 2 to 6	Symptoms include general muscle weakness and wasting. It affects the pelvis, upper arms, and upper legs. Over time, it includes all voluntary muscles. Survival beyond the 20s is rare. It happens mostly in boys. Very rarely it can affect women, who have much milder symptoms and a better prognosis.
Distal	Ages 40 to 60	Symptoms include weakness and wasting of muscles of the hands, forearms, and lower legs. Progression is slow. It rarely leads to total disability.
Emery-Dreifuss	Childhood to early teens	Symptoms include weakness and wasting of shoulder, upper arm, and shin muscles. Joint deformities are common. progression is slow. Sudden death may occur from cardiac problems.
Facioscapulohumeral	Childhood to early adults	Symptoms include facial muscle weakness and weakness with some wasting of shoulders and upper arms. Progression is slow with periods of rapid deterioration. Life span may be many decades after onset.
Limb-Girdle	Late childhood to middle age	Symptoms include weakness and wasting, affecting shoulder girdle and pelvic girdle first. Progression is slow. Death is usually due to cardiopulmonary complications.
Myotonic	Ages 20 to 40	Symptoms include weakness of all muscle groups and delayed relaxation of muscles after contraction. It affects the face, feet, hands, and neck first. Progression is slow, sometimes spanning 50 to 60 years. An infantile form causes more severe problems.
Oculopharyngeal	Ages 40 to 70	Symptoms affect muscles of eyelids and throat causing weakening of throat muscles. Over time, this causes inability to swallow and severe weight loss from lack of food. Progression is slow.