Table 1 The International Classification of Headache Disorders (ICHD-II): post-traumatic headache

5.1 Acute post-traumatic headache

5.1.1 Acute post-traumatic headache attributed to moderate or severe head injury

Diagnostic criteria

A. Headache, no typical characteristics known, fulfilling criteria C and D

B. Head trauma with at least one of the following

 1. loss of consciousness for >30 min

 2. Glasgow coma scale (GCS) < 13

 3. post-traumatic amnesia for >48 h

 4. imaging demonstration of a traumatic brain lesion (cerebral haematoma, intracerebral and/or subarachnoid haemorrhage, brain contusion and/or skull fracture)

C. Headache develops within 7 days after head trauma or after regaining consciousness following head trauma

D. One or other of the following:

 1. headache resolves within 3 months after head trauma

 2. headache persists but 3 months have not yet passed since head trauma

5.1.2 Acute post-traumatic headache attributed to mild head injury

Diagnostic criteria

A. Headache, no typical characteristics known, fulfilling criteria C and D

Head trauma with all the following

 1. either no loss of consciousness, or loss of consciousness of <30 min duration

 2. Glasgow coma scale (GCS) ≥ 13

 3. symptoms and/or signs diagnostic of concussion

Headache develops within 7 days after head trauma

D: One or other of the following

 1. headache resolves within 3 months after head trauma

 2. headache persists but 3 months have not yet passed since head trauma

5.2 Chronic post-traumatic headache

5.2.1 Chronic post-traumatic headache attributed to moderate or severe head injury

Diagnostic criteria

A. Headache, no typical characteristics known, fulfilling criteria C and D

B. Head trauma with at least one of the following

 1. loss of consciousness for >30 min

 2. Glasgow coma scale (GCS) < 13

 3. post-traumatic amnesia for >48 h

 4. imaging demonstration of a traumatic brain lesion (cerebral haematoma, intracerebral and/or subarachnoid haemorrhage, brain contusion and/or skull fracture)

C. Headache develops within 7 days after head trauma or after regaining consciousness following head trauma

D. Headache persists for >3 months after head trauma

5.2.2 Chronic post-traumatic headache attributed to mild head injury

Diagnostic criteria

A. Headache, no typical characteristics known, fulfilling criteria C and D

B. Head trauma with all the following

 1. either no loss of consciousness, or loss of consciousness of <30 min duration

 2. Glasgow coma scale (GCS) ≥ 13

 3. symptoms and/or signs diagnostic of concussion

C. Headache develops within 7 days after head trauma

D. Headache persists for >3 months after head trauma