[Exploration of extra-cephalic pain induced in essential headaches]

The deep pain threshold and migrainous patient's tolerance were investigated by different methods such as: the post-ischemic stasis, muscular exercise in an ischemic condition, sural pressure, comparing them with the cold pain test employed to assess the superficial pain threshold. The tests were carried out simultaneously and symmetrically to both extremities in order to check the possible asymmetry of the pain threshold. Migrainous patients showed a reduced threshold and a lower tolerance to deep pain, while this is not evident when testing the superficial threshold. The simultaneous measurement of both extremities showed higher differences in migrainous patients than in control patients. The meaning of the change of systemic pain is discussed, with special reference to the possible correlation with the hypothesis of a central origin of pain in essential headaches.