[Surface electromyography during experimental stress as a tool in the diagnosis of tension headache: results in 100 cases].

We report the use of surface scalp and neck electromyography during experimental stress state in a series of 100 out-patients suffering from chronic tension headache. Results revealed a 24% to 32% of diagnostic errors in the diagnostic obtained by routine anamnestic procedures and following the criteria recommended by the Headache Classification Committee of the International Headache Society (1988). The electromyography with stress is proposed as a new diagnostic criterion for tension headache.