Idiopathic cervical dystonia: clinical characteristics.

We reviewed detailed clinical features of 266 patients with idiopathic cervical dystonia, commonly called spasmodic torticollis. Mean age at onset (41 years), female-to-male ratio (1.9:1), clustering of onset between ages 30 and 59 (70%), familial history of dystonia (12%), and remissions (9.8%) were similar to those found in previous studies. In contrast to the single prior large clinical study of this disorder, no predominance of right-handers or significant thyroid disease was found. Pain, which occurred in 75% of patients and contributed to disability score (p less than 0.01), distinguishes this syndrome from all other focal dystonias. Pain was also strongly associated with constant (vs. intermittent) head turning, severity of head turning, and presence of spasm. Eighty-three percent of patients had deviation of the head of greater than 75% of the time when sitting with the head unsupported (constant head deviation at rest). Of the 97% who had head turning, 81% also had head tilting in various combinations. The 23% with hand tremor had an older age at onset (mean, 46 vs. 41 years; p less than 0.05). An earlier age at onset (p less than 0.05) was seen in patients with a family history of dystonia (mean, 36 years), with trauma shortly preceding symptoms (mean, 36 years), with a change in the direction of head turning (mean, 30 years), and with remissions (mean, 33 years). Jerky movements or forced transient spasms of the head occurred in 62% of the patients, and these patients would be the ones for whom the designation "spasmodic torticollis" could logically apply.(ABSTRACT TRUNCATED AT 250 WORDS)