Type : Phenotype or locus, molecular basis unknown;
Alternative titles and symbols : Torsion dystonia, focal adult-onset;
Included titles and symbols : Cervical dystonia, primary;
Description : Idiopathic torsion dystonia (ITD) is a clinically and genetically heterogeneous group
of movement disorders characterized by sustained dystonic muscle contractions causing
involuntary twisting movements and/or postures, where causes such as cerebral lesions
(especially of the basal ganglia), drugs, or other neurologic disorders have not been
found. Adult-onset torsion dystonia usually remains focal and is localized in the
upper part of the body (summary by Leube et al., 1996).;