EMG investigations in patients with torticollis.

EMGs have been performed on patients suffering from organic torticollis, hysterical torticollis and on normal control subjects. The EMG activity of the sternomastoid muscles during head rotation in control subjects and those with hysterical torticollis showed similar characteristics and neither group showed a response to body tilt. Subjects suffering from organic torticollis, however, did show a response to tilt. The results suggest that the response to backward tilt might aid in distinguishing the organic and hysterical forms of torticollis.