Generalized Dystonia

Primary   generalized dystonia, also called idiopathic torsion dystonia or dystonia musculorum deformans is a disabling neurological condition which commonly starts in childhood, generally in a lower limb and spreads to other body parts as the disease progresses. Medical treatment is typically ineffective and most patients become wheelchair bound or even bedridden.

Dystonia is the third most frequent movement disorder. Manifestations can be focal, with spasmodic torticollis (cervical dystonia), blepharospasm, spasmodic dysphonia, "writers cramp" and other task specific dystonias.

Dystonia can also be generalized, leading to involuntary twisting of the limbs and trunk. Dystonia is defined as "primary" when it occurs in isolation (without other neurologic or medical problems) or as "secondary" when it occurs in conjunction with other neurological diseases and/or environmental insults. Numerous pathophysiological mechanisms have been suggested to clarify the variable onset of dystonia, including a childhood-adolescent window of susceptibility, low penetrance within genetic subtypes, and various supposed environmental triggers.

Dystonia appears to be a centrally mediated dysregulation of movement resulting from abnormalities in discrete regions of the brain. In some forms of familial dystonia, particular mutations have been identified, which offer additional insights into pathophysiological pathways.