Post-Traumatic Headaches After Accidents: Causes Explained

Why Headaches After an Accident May Involve Both the Brain and the Cervical Spine

By Dr. Alex Jimenez, DC, APRN, FNP-BC, CFMP, IFMCP

Abstract

A headache that begins after a motor vehicle collision, fall, sports impact, or other accident is not always generated by a single injured structure. The same traumatic event may expose the brain to rapid acceleration forces while simultaneously straining the cervical joints, muscles, ligaments, discs, and nerves. The result can be overlapping headache patterns involving post-traumatic neurological changes, cervical pain, altered sensory processing, dizziness, light or sound sensitivity, and migraine-like symptoms.

Modern evaluation therefore requires more than simply asking, “Does the patient have a headache?” Clinicians must determine which neurological and musculoskeletal mechanisms the history, examination, functional findings, and, when appropriate, diagnostic testing reasonably support. Current evidence increasingly supports a multidisciplinary and phenotype-guided approach to post-traumatic headache rather than assuming every patient has the same injury or requires the same treatment (Aguirre et al., 2026; Díaz & Lehman, 2026; Jimenez & Danan, 2026).

One Accident Can Affect More Than One System

Imagine a patient stopped at a traffic light when another vehicle strikes the rear of the car.

For a fraction of a second, the torso moves with the seat while the head responds differently. The neck may rapidly extend and flex. Muscles tighten. Cervical joints are loaded. The head may rotate or strike the headrest, window, steering wheel, or another surface.

Afterward, the patient develops neck stiffness and a headache.

By the following day, additional symptoms appear:

• Sensitivity to light
• Dizziness
• Difficulty concentrating
• Pain behind the eyes
• Nausea
• Pain at the base of the skull
• Difficulty turning the neck
• Fatigue
• Sensitivity to sound

1. Is this a concussion-related headache?
2. Is it a cervical headache?
3. Is it migraine?

The clinically responsible answer is that several mechanisms may be possible, and each must be evaluated.

The International Classification of Headache Disorders recognizes headaches following both traumatic head injury and whiplash. Importantly, post-traumatic headaches frequently resemble migraine or tension-type headaches, meaning the way the pain feels does not necessarily identify where it originated (Headache Classification Committee of the International Headache Society [IHS], 2018).

That is why diagnosis begins with the entire injury story.

What Rapid Acceleration and Deceleration Do to the Head and Neck

Whiplash is more than simply a “sore neck.”

The ICHD-3 defines whiplash as sudden acceleration-deceleration movement of the head involving neck flexion and extension. It can occur during both higher- and lower-impact events (IHS, 2018).

During a collision, several events can occur almost simultaneously.

The Cervical Spine Is Mechanically Loaded

The cervical spine contains vertebrae, facet joints, discs, muscles, ligaments, connective tissues, and nerve structures designed to support and move the head.

Rapid motion can load these tissues beyond their usual movement patterns.

Depending on the mechanism and the individual patient, clinicians may find:

• Cervical muscle guarding
• Reduced range of motion
• Joint tenderness
• Pain with specific movements
• Myofascial trigger points
• Upper cervical irritation
• Occipital nerve sensitivity
• Ligamentous or soft-tissue injury
• Disc-related symptoms
• Referred pain into the head

Recent research specifically emphasizes that cervical facet joints, musculoligamentous structures, occipital nerves, and cervical discs may contribute to symptoms in some people with post-traumatic headache (Jimenez & Danan, 2026).

For readers interested in the biomechanics of collision injury, see Rear Impact Whiplash: Understanding the Injury, which follows an integrated chiropractic and medical evaluation of a rear-impact collision. Read the rear-impact whiplash case

The Brain May Also Be Exposed to Traumatic Forces

Head injury does not always require a dramatic direct blow.

Acceleration, deceleration, rotation, or an impact can produce functional neurological effects associated with mild traumatic brain injury or concussion.

Possible symptoms include:

• Headache
• Dizziness
• Balance difficulty
• Nausea
• Visual disturbance
• Light sensitivity
• Sound sensitivity
• Cognitive slowing
• Difficulty concentrating
• Memory problems
• Sleep disturbance
• Fatigue

The CDC notes that concussion symptoms may appear immediately or may evolve over hours or days following trauma (Centers for Disease Control and Prevention [CDC], 2025).

Post-traumatic headache is particularly common following mild traumatic brain injury. Research indicates that it frequently has migraine-like or tension-type characteristics, although emerging evidence suggests that post-traumatic headache is not simply ordinary migraine occurring after an accident (Schwedt, 2024; Díaz & Lehman, 2026).

Why Post-Traumatic Headaches Can Feel Like Migraines

One reason these cases become confusing is that symptoms overlap.

A patient with post-traumatic headache may report:

• Throbbing pain
• Light sensitivity
• Sound sensitivity
• Nausea
• Worsening with activity
• One-sided head pain
• Visual sensitivity
• Scalp tenderness

Those symptoms can strongly resemble migraine.

A large clinical study of patients with post-traumatic headache found migraine-like features such as photophobia, phonophobia, nausea, pulsating pain, and worsening with routine activity to be common (Cortel-LeBlanc et al., 2025).

This does not mean trauma “turns into migraine.”

It means traumatic headache can produce a phenotype that resembles migraine.

Modern research is investigating mechanisms involving neuroinflammation, neurometabolic changes, central sensitization, CGRP signaling, autonomic dysfunction, and altered sensory processing (Aguirre et al., 2026; Díaz & Lehman, 2026).

Patients may therefore become unusually sensitive to ordinary sensory input.

Light feels brighter.

Noise feels louder.

Touch may become uncomfortable.

Movement may provoke a headache.

Sensory hypersensitivity has also been associated with greater post-traumatic headache disability (Ishii et al., 2023).

The Neck and Brain Share Pain-Processing Pathways

Another important piece of this puzzle is the trigeminocervical complex.

Sensory information from structures in the head and upper cervical spine converges within closely connected neurological pathways in the upper spinal cord and brainstem.

This anatomical overlap helps explain why irritation arising from the neck can be experienced as pain in the:

• Back of the head
• Temples
• Forehead
• Eye region
• Face

It also helps explain why cervical dysfunction can coexist with migraine-like symptoms.

Cervicogenic headache, for example, can sometimes include nausea, dizziness, photophobia, or phonophobia—features many people typically associate only with migraine (Castaldo et al., 2025).

Conversely, a person experiencing migraine or post-traumatic neurological sensitization may develop increased cervical tenderness without the neck necessarily being the primary cause of the entire headache.

This relationship can therefore operate in both directions.

My detailed discussion of this neurological connection is also available in Chiropractic Rehabilitation for Relief From Migraines, including an explanation of the cervical spine and trigeminocervical complex. Read about migraine and cervical rehabilitation.

Why Examining Only the Brain—or Only the Neck—Can Miss Part of the Picture

Consider a patient with headache, dizziness, neck stiffness, and sensitivity to light after a rear-end collision.

A neurological examination may help identify concerns involving concussion, balance, cognition, vision, coordination, or sensory processing.

A cervical examination may identify restricted motion, muscular tenderness, mechanical pain, neurological irritation, or other musculoskeletal abnormalities.

These are not competing explanations.

The accident may have affected both systems.

Current Department of Defense concussion guidance specifically recognizes headache, cervical, vestibular, cognitive, oculomotor, and sleep-related symptom clusters that may require different assessment and treatment strategies (Traumatic Brain Injury Center of Excellence, 2024).

That creates an important clinical principle:

Symptoms can overlap, but diagnoses should not be assumed simply because symptoms overlap.

Establishing What the Accident Actually Caused

This distinction matters especially in personal injury cases.

Finding a headache after an accident does not, by itself, prove what structure generated it.

Similarly:

• Neck pain does not automatically prove cervical injury.
• Dizziness does not automatically prove concussion.
• An abnormal MRI does not automatically prove that trauma caused the abnormality.
• Migraine-like symptoms do not automatically mean the patient developed primary migraine.
• Improvement with treatment does not independently prove the original cause.

Clinical causation requires a structured analysis.

Clinicians may consider:

1. Mechanism of injury — What forces acted on the head and cervical spine?
2. Temporal relationship — When did symptoms begin?
3. Pre-accident baseline — Did similar headaches or neck problems exist before the event?
4. Immediate symptoms — Was there confusion, dizziness, memory disruption, nausea, neck pain, or headache?
5. Objective examination findings — Are there reproducible neurological or musculoskeletal abnormalities?
6. Diagnostic studies — Is imaging or additional testing medically indicated?
7. Differential diagnosis — Are there alternative explanations?
8. Clinical course — Do symptoms and functional limitations behave consistently with the suspected injury?

The ICHD-3 uses the temporal relationship to trauma as an important part of classifying traumatic headache. Headaches arising after whiplash or traumatic head injury are classified as acute during the first three months and persistent when they continue beyond three months, assuming applicable diagnostic criteria are met (IHS, 2018).

For a deeper discussion of this process, see Accident Injury Medical Causation in El Paso, which explains mechanism, symptom chronology, pre-existing conditions, examination findings, imaging, and differential diagnosis. Read about accident injury medical causation.

How an Integrated Examination Guides Treatment

Once clinicians understand which systems appear to be contributing, treatment can become much more precise.

A patient with predominantly neurological post-traumatic headache may require strategies directed toward the headache phenotype, activity progression, sleep, sensory tolerance, medication management, vestibular rehabilitation, vision-related symptoms, or neurological consultation.

A patient with documented cervical musculoskeletal involvement may benefit from appropriately selected cervical rehabilitation that can include:

• Mobility exercises
• Progressive strengthening
• Postural rehabilitation
• Soft-tissue treatment
• Manual therapy
• Chiropractic techniques when clinically appropriate
• Neuromuscular retraining
• Acupuncture or electroacupuncture in selected patients
• Gradual return to functional activity

When clinicians identify cervical impairments in migraine-like presentations, they should address those findings as part of an individualized plan rather than assuming every headache originates in the neck (Castaldo et al., 2025).

Likewise, treatment directed at the cervical spine should not substitute for appropriate neurological assessment when symptoms suggest concussion or another brain-related condition.

The goal is not to decide that the headache is “all brain” or “all neck.”

The goal is to determine which clinically supported contributors are present in this particular patient.

Why Injury Medical Chiropractic and Functional Medicine Clinic Is Different

At Injury Medical Chiropractic and Functional Medicine Clinic in El Paso, our model is designed for precisely these overlapping injury presentations. Dr. Maria Guadalupe Cardenas, MD, a board-certified internal medicine physician with more than four decades of clinical experience, serves as medical director and collaborative physician. I serve as both a Doctor of Chiropractic and a board-certified Family Nurse Practitioner, allowing our team to integrate medical assessment with specialized evaluation of soft-tissue, spinal, neuromusculoskeletal, and functional injuries.

This combination allows us to coordinate neurological concerns, cervical findings, medication considerations, rehabilitation needs, diagnostic testing, and appropriate specialist referrals within one multidisciplinary clinical framework. Our clinic is one of the few El Paso practices structured to provide this breadth of integrated medical, chiropractic, rehabilitation, acupuncture, electroacupuncture, and functional medicine services under coordinated medical direction. The objective is not to force every patient into one treatment pathway but to identify the safest and most appropriate combination of care for that individual’s presentation. The clinic’s current website identifies Dr. Cardenas as medical director and collaborative physician and describes the practice’s multidisciplinary medical and chiropractic integration.

One Accident, Several Possible Sources

The most important lesson is simple.

A single accident can produce several interacting symptom sources.

A patient might have:

• A concussion-related headache
• Cervical soft-tissue injury
• Cervicogenic headache features
• Migraine-like sensory hypersensitivity
• Occipital nerve irritation
• Vestibular dysfunction
• Sleep disruption
• Muscular guarding

These findings can influence one another.

However, the existence of one does not automatically prove the existence of another.

Each suspected cause deserves its own clinical reasoning.

That protects the patient from both underdiagnosis and overdiagnosis.

It also protects patient autonomy. A person who understands why a clinician suspects a neurological component, a cervical component, or both can make more informed decisions about imaging, medical treatment, chiropractic care, rehabilitation, medication, acupuncture, specialist referral, and return to work or activity.

When a Post-Accident Headache Requires Urgent Attention

Most post-accident headaches are not signs of a life-threatening emergency, but certain symptoms require immediate medical attention.

Following a head injury, emergency evaluation is warranted for warning signs such as:

• A headache that progressively worsens and does not resolve
• Repeated vomiting
• Seizure
• Increasing confusion or unusual behavior
• Slurred speech
• New weakness or numbness
• Significant loss of coordination
• One pupil becoming larger than the other
• Increasing difficulty remaining awake
• Loss of consciousness or inability to awaken normally

These findings may indicate a more serious neurological injury and should not be managed as a routine musculoskeletal headache (CDC, 2025).

The Clinical Bottom Line

After an accident, asking “Is the headache coming from the brain or the neck?” may create a false choice.

For some patients, one source clearly predominates.

For others, the answer may be both.

Head acceleration and traumatic neurological changes can influence sensory processing and produce migraine-like symptoms. At the same time, rapid cervical acceleration-deceleration can injure muscles, ligaments, joints, discs, and nerve structures that can refer pain into the head.

Modern post-traumatic headache evaluation therefore works best when clinicians examine neurological, musculoskeletal, vestibular, visual, sensory, sleep, and functional factors together.

Treatment should then follow the evidence found in that individual patient.

One accident may create several interacting problems.

But every suspected problem still has to earn its diagnosis.

That distinction is the foundation of responsible, patient-centered post-traumatic headache care.

---

References

Aguirre, A. S., Elhefnawy, Y., & Torres, A. R. (2026). Assessment and management of post-traumatic headache. Current Neurology and Neuroscience Reports, 26(1). Assessment and Management of Post-traumatic Headache

Castaldo, M., Arendt-Nielsen, L., & Di Antonio, S. (2025). A clinical guide for physiotherapists to assess and manage cervical musculoskeletal impairment and pain sensitivity in migraine patients. Journal of Manual & Manipulative Therapy, 33(5), 412–429. Clinical guide to cervical musculoskeletal impairment in migraine

Centers for Disease Control and Prevention. (2025). Symptoms of mild TBI and concussion. CDC mild TBI and concussion symptoms

Cortel-LeBlanc, A., Cortel-LeBlanc, M., Webster, R. J., Chen, K., Schytz, H. W., Jolliffe, K., Dodd, A. B., Terekhov, I., Dashti, F., & Zemek, R. (2025). Post-traumatic headache phenotypes and clinical characteristics. Cephalalgia, 45(12). Post-traumatic headache phenotypes and clinical characteristics

Díaz, P. G., & Lehman, A. B. (2026). Phenotype-guided management of post-traumatic headache: An update on pathophysiology and treatment. Current Pain and Headache Reports, 30(1). Phenotype-guided management of post-traumatic headache

Headache Classification Committee of the International Headache Society. (2018). The International Classification of Headache Disorders, 3rd edition. Cephalalgia, 38(1), 1–211. ICHD-3: Headache attributed to trauma or injury to the head and/or neck

Ishii, R., et al. (2023). Sensory hypersensitivities are associated with post-traumatic headache-related disability. Sensory hypersensitivity and post-traumatic headache disability

Jimenez, V., & Danan, I. (2026). Implications of cervical spine conditions on post-traumatic headaches. Clinics in Sports Medicine, 45(2), 327–341. Implications of Cervical Spine Conditions on Post-Traumatic Headaches

Schwedt, T. J. (2024). Posttraumatic headache. Continuum, 30(2), 411–424. Posttraumatic Headache

Traumatic Brain Injury Center of Excellence. (2024). Assessment and management of headache following concussion/mild traumatic brain injury: Guidance for the primary care manager. U.S. Department of Defense. DoD clinical recommendation for headache following concussion/mTBI