Clinical characteristics of nummular headache and differentiation between spontaneous and posttraumatic variant: an observational study.

Background: Head trauma has been described as a precipitating event in Nummular Headache (NH). We aimed to describe the largest NH published series and compare characteristics between idiopathic and post-traumatic cases.

Methods: Patients attended in a Headache Unit in a tertiary hospital (January 2008-January 2018).