Dystonia can affect different parts of the body. The disease is classified by what part of the body is affected. These classifications include:
- Generalized dystonia, which affects most or all of the body
- Focal dystonia, which affects one body part
- Multifocal dystonia, affecting multiple unrelated body parts
- Segmental dystonia, affecting adjacent body parts
- Hemidystonia, which affects one side of the body.
There are also several types of dystonia related to the eyes, face, neck, jaw, throat, and more.
Early symptoms of dystonia are typically mild, such as a dragging leg, cramping of a foot, involuntary movement of the neck, or uncontrollable blinking. These symptoms usually appear or worsen with exertion, stress, fatigue, and certain activities. Constant muscle contractions can lead to pain and exhaustion. The condition may progress to where the abnormal movements and postures happen while walking or at rest. In some forms of dystonia, the tendons shorten, causing permanent restrictions in affected areas of the body.
The age when dystonia starts can affect how it progresses. If dystonia begins in childhood, symptoms often start in a hand or foot and quickly spread to the rest of the body before the progression slows in adolescence. If dystonia begins in young adulthood, symptoms usually start in the upper body and slowly progress. And if it starts in later adulthood, symptoms typically only affect one muscle or area of the body.