Torticollis as an initial symptom of adult-onset dystonia musculorum deformans

Dystonia musculorum deformans (DMD) is an idiopathic movement disorder which usually involves pediatric age group and progresses to the generalized type. On the contrary in adult-onset DMD, dystonia is usually confined to an upper extremity and its clinical course is benign. The authors report seven patients with adult-onset DMD whose initial symptom was confined to the neck. Diagnosis of idiopathic spasmodic torticollis had been made in all of them. Average ages at the onsets of torticollis and extranuchal dystonia were 49 +/- 13 and 54 +/- 9 years (mean +/- SD) respectively. The duration between these onsets was 2-3 years in five patients and 10-17 years in two younger patients. Two patients finally developed generalized dystonia and one patient became hemidystonic type. These findings suggest that some patients diagnosed as idiopathic spasmodic torticollis are in an early stage of DMD and that this particular type progresses more likely to the generalized form than other types of adult-onset DMD.