Tension-type headache and fibromyalgia: what's common, what's different?

Chronic tension-type headache and fibromyalgia have striking clinical and pathophysiologic similarities. They can be associated in patients. In both conditions there is evidence of altered processing of peripheral nociceptive information. Peripheral sensitisation of musculotendinous nociceptors may play a role and, at least in chronic tension-type headache, there are indications of central sensitisation. As for the clinical presentation, there also pathophysiological differences between the two disorders. A better understanding of both these differences and similarities may hopefully help in the future management of patients.