Secondary dystonias result from apparent outside factors
and can be attributed to a specific cause such as exposure to certain medications,
trauma, toxins, infections, or stroke.
Spinal cord injury, head, and peripheral injury are also
recognized contributors to dystonia.
Other examples of secondary dystonias include drug-induced
dystonias and dystonias associated with cerebral palsy, cerebrovascular
disease, cerebral infections and postinfectious states, stroke, encephalitis,
brain tumor, and toxins.
Secondary dystonia includes dystonia associated with
approximately 50 neurological and metabolic diseases.
A number of secondary dystonias do not present as pure
dystonia, but with a mixture of other neurologic features, such as parkinsonian
features like slowness of movement and rigidity.
Secondary dystonias may differ from primary dystonias in
that symptoms may not disappear during sleep.
Treatment is highly customized to the individual and may be
directed by what is known about the cause.