Post-traumatic headache: from classification challenges to biological underpinnings.

The ICHD-II criteria for post-traumatic headache (PTH) are strictly outlined. PTH can be subdivided into an acute and a chronic forms, the former likely nociceptive in nature, the latter likely neuropathic. The time of transition between the acute and the chronic forms is artificial and in the future should be better based on clear clinical or rather biological data. Chronic PTH often presents as one of the primary headache syndromes, e.g. migraine or tension-type headache. Its biology is poorly understood and whether it merely represents the expression of the primary headache or it has a distinct pathogenesis remains unclear. The frontal lobe is often affected in traumatic head injury. Its dysfunction can cause an array of clinical consequences that have an impact on the patient's symptomatology and therapeutic outcome. Its recognition is likely to improve patient management quality.