Not so strange, do some research on the nervous system, it's the most complex system in the body. For instance, the left side of your brain, controls the right side of your body, and the right half of the brain controls the left side of the body.
For dystonia: (from wikipedia)
The causes of dystonia are not yet known or understood; however, they are categorized as follows on a theoretical basis:
Primary dystonia is suspected to be caused by a pathology of the
central nervous system, likely originating in those parts of the
brain concerned with motor function, such as the
basal ganglia, and the GABA (
gamma-aminobutyric acid) producing
Purkinje neurons. The precise cause of primary dystonia is unknown. In many cases it may involve some genetic predisposition towards the disorder combined with environmental conditions.
Secondary dystonia refers to dystonia brought on by some identified cause, usually involving brain damage, or by some unidentified cause such as chemical imbalance. Some cases of (particularly focal) dystonia are brought on after trauma, are induced by certain drugs (tardive dystonia), or may be the result of diseases of the nervous system such as
Wilson's disease.
Environmental and task-related factors are suspected to trigger the development of focal dystonias because they appear disproportionately in individuals who perform high precision hand movements such as musicians, engineers, architects and artists.
There is limited treatment options available, they seem to play around with various medications generally used for Parkinson's Disorder. These treatments do not cure Dystonia, but can lessen the pain and reduce triggers of the spasms, etc.
