What Causes Tension-Type Headaches After Head Trauma
Post-traumatic tension-type headache is caused by peripheral activation and sensitization of myofascial nociceptors in the pericranial and cervical muscles, which—when sustained—can lead to central nervous system sensitization and chronification of the headache disorder. 1, 2
Primary Pathophysiological Mechanisms
Peripheral Myofascial Mechanisms
Cervical strain commonly co-occurs with concussion-related headache, particularly when pain is occipital or sub-occipital, because injury to cervical structures produces somatosensory dysfunction and abnormal signaling along cervical afferent pathways. 2
The peripheral activation or sensitization of myofascial nociceptors in pericranial and cervical muscles is the most probable mechanism involved in the acute episode of post-traumatic tension-type headache. 3, 4
Patients with tension-type headache after trauma exhibit cervical spine sensitivity, forward head posture, limited cervical range of motion, positive flexion-rotation test, and cervical motor control disturbances. 5
Manual examination of upper cervical joints and muscle trigger points reproduces the characteristic pain pattern seen in tension-type headache. 5
Central Sensitization Pathway
Repetitive episodes of muscle pain may sensitize the central nervous system, resulting in progression from episodic to chronic post-traumatic tension-type headache. 3
When headache persists beyond 2 months after injury, it is classified as chronic post-traumatic headache and reflects increased excitability of the central nervous system generated by repetitive and sustained pericranial myofascial input. 1, 6
Sensitization of central nociceptive pathways and inadequate endogenous antinociceptive circuitry become more relevant as the condition becomes chronic. 7
Clinical Recognition Framework
Diagnostic Criteria
The American Association of Neurological Surgeons formally classifies headache/migraine as one of five primary concussion subtypes (cognitive, ocular-motor, vestibular, anxiety/mood, and headache), establishing post-traumatic headache as a distinct clinical entity. 1
Post-traumatic headache is defined as headache beginning within 2 weeks of closed head injury; persistence beyond 2 months defines chronic post-traumatic headache. 1, 2
Characteristic Presentation
Post-traumatic tension-type headache typically presents as bilateral, mild-to-moderate pressure or tightening pain without classic migraine features (unilateral throbbing, nausea, photophobia, or worsening with routine physical activity). 1
Evaluation should specifically assess for cervical spine tenderness (midline, paraspinal, sub-occipital), weakness on paracervical strength testing, limited cervical range of motion, and pain provoked by cervical movement. 2
Important Clinical Caveats
Concussion subtypes are not mutually exclusive—a patient may initially exhibit tension-type features and later develop migraine-like or anxiety/mood components, necessitating ongoing reassessment. 1
Distinguishing isolated cervical strain from whiplash-associated disorder is crucial, as both share injury mechanisms but require different management strategies. 2
In the cervical spine context: for cervicogenic headache the neck is the source (cause) of headache, whereas in tension-type headache the neck has a component contributing to the pain pattern but is not the primary cause since tension-type headache is a primary headache disorder. 5
Approximately 37–40% of patients who develop post-traumatic headache are diagnosed with a chronic tension-type phenotype, making it one of the most common chronic post-traumatic headache presentations. 1