[Clinical studies of writer's cramp in 30 patients]

30 patients with writer's cramp were examined by a neurologist and a psychiatrist. The syndrome was frequently associated with a postural tremor. We found no evidence for a peripheral causation. Electromyographical recordings showed co-contractions of agonists and antagonists as well as individual patterns of increased muscle activity during writing. CT and MRI scans were normal in most patients. The psychiatric examination revealed a history of situational stress at the onset of the disease and also some abnormalities in the biography and personality traits. Since the latter findings were not consistently present we have no evidence that the disease is a neurotic manifestation. We consider it likely that secondary psychoreactive processes may have some significance in the individual patient.