Effect of movement and position on muscle activity in tension headache sufferers during and between headaches.

This paper presents the results of two studies. In the first, 20 tension headache subjects were evaluated in both a headache and non-headache state on bilateral trapezius and unilateral frontalis electromyographic activity during six positions: standing, bending from the waist, rising, sitting with back unsupported, sitting with back supported, and prone. Results indicated no effect of headache state on either measure. In a second study, 11 of the tension headache sufferers in Study One and 11 age-matched controls were compared on the same measures (controls were assessed two times, with a one-week duration separating evaluations). Results indicated a diagnosis by position interaction, with post-hoc tests revealing the muscle activity of tension headache sufferers to be considerably higher during the prone position than that of non-headache controls. Non-significant trends were found when examining the data for clinically significant abnormalities (90% of the headache sufferers were found to have significant clinical abnormalities).