Migraine, neuropathic pain and nociceptive pain: towards a unifying concept

Migraine, neuropathic pain and nociceptive pain are the three commonest pain syndromes affecting human. In the present article, we first present the salient features of the pathophysiology of the three conditions particularly highlighting the core features that are similar in the three conditions. We argue on the validity of the prevailing concept that maintenance of structural integrity of the nervous system differentiates nociceptive pain from neuropathic pain and point out that the fundamental pathophysiology of lasting nociceptive pain (like cancer pain) and neuropathic pain (like nerve injury pain) is essentially same. Migraine pathophysiology is complex and complicated by two opposing views on site of migraine pain generation - peripheral versus central. We hypothesize that this dichotomy has resulted from focusing on two different sites on a single, somewhat complicated, pain mediating circuitry from the peripheral meningeal and vascular structures through several cell stations in the brain stem and thalamus up to the sensory cortical matrix. At the end, we suggest that fundamentally all the three pain syndromes referred to in the article share a common pathophysiological mechanism, namely peripheral pain perception, peripheral sensitization at dorsal root ganglion or its intracranial counterpart (like trigeminal ganglion) and central sensitization at the spinal cord (dorsal horn for somatic pain), brain stem nuclei and thalamus before final pain perception at the sensory cortical matrix.