Electromyographic study in an infant with benign paroxysmal torticollis.

The findings of surface electromyography (s-EMG) in a female with benign paroxysmal torticollis in infancy (BPT) are reported. This disease is characterized by (1) a self-limiting condition that appears in early infancy and disappears spontaneously, (2) recurrent episodes of sudden, stereotypic torticollis, usually alternating from side to side, and (3) episodes that usually continue for several hours to a few days. The pathogenesis of this disease has not been determined. During episodes in the patient, continuous electrical discharges over the sternocleidomastoid muscle on the same side as the torticollis were observed on s-EMG, indicating that the torticollis was a dystonic phenomenon. The findings are clinically consistent with BPT, and the patient should be categorized as having an idiopathic paroxysmal dystonia in infancy.