Chronic Occipital Headache (3 months duration) - Causes & Differential Diagnosis

Anatomical Basis

Differential Diagnosis by Category

1. Occipital Neuralgia

• Paroxysmal, stabbing or electric shock-like pain starting in the nuchal region, immediately spreading to the vertex
• Pain follows the distribution of the greater (C2), lesser (C2-C3), or third occipital nerve (C3)
• Tenderness on palpation/percussion over the occipital nerve trunks
• May be triggered by hair brushing or neck movement
• Background dull occipital ache between episodes
• Confirmed diagnostically by transient relief with local anesthetic nerve block
• Causes include: whiplash injury, cervical spondylosis, nerve entrapment, or infiltrating lesions

2. Cervicogenic Headache

• Pain referred from pathology in the neck (C2-C3 dermatomes) to the head
• Frequently localized to the occipital area but may radiate to frontal, temporal, or orbital regions
• Triggered by neck movements or sustained postures
• Constant pain with episodic exacerbations
• Associated with nausea, photophobia, phonophobia - easily mistaken for migraine without aura
• Examination: tenderness over greater/lesser occipital nerves, cervical facet joints, upper cervical muscles
• Common underlying pathology: degenerative cervical spondylosis, facet joint arthropathy, post-whiplash injury
• Does not respond well to migraine medications

3. "Third Occipital Nerve" Headache

• Unilateral occipital and suboccipital ache, particularly after neck injuries (prevalence ~27% in neck pain patients)
• Caused by degenerative or traumatic arthropathy of the C2-C3 facet joints impinging on the third occipital nerve (branch of C3 dorsal ramus)
• Diagnosis confirmed by percutaneous fluoroscopic nerve block
• Treated with radiofrequency coagulation, steroid injections, or NSAIDs

4. Tension-Type Headache (TTH)

• Most common primary headache, can cause occipital predominance
• Bilateral, pressing/tightening, non-pulsating quality
• Mild-to-moderate intensity, not aggravated by routine activity
• Associated with pericranial muscle tenderness - posterior cervical and suboccipital muscles commonly involved
• Chronic TTH: >15 headache days/month for >3 months
• No nausea, vomiting, photophobia, or phonophobia (unlike migraine)

5. Migraine (with occipital predominance)

• Occipital location is less typical but occurs, especially basilar-type/migraine with brainstem aura
• Pulsating, moderate-to-severe, unilateral or bilateral
• Associated photophobia, phonophobia, nausea/vomiting
• Postcoital headache is often occipital or frontal and throbbing
• Migraine can also be triggered by and overlap with cervicogenic headache

6. Posterior Fossa Tumors / Space-Occupying Lesions

• Tumors in the posterior fossa characteristically cause occipital headache
• Headache worsened by Valsalva, coughing, straining
• Projectile vomiting that precedes headache is characteristic of posterior fossa masses
• May present with ataxia, nystagmus, cranial nerve signs, papilledema
• Red flags: progressive worsening, nocturnal awakening, new neurological deficits

7. Idiopathic Intracranial Hypertension (Pseudotumor Cerebri)

• Occipital pressure/heaviness, worse when lying down
• Associated with pulsatile tinnitus, transient visual obscurations, diplopia
• Papilledema on fundoscopy
• Risk factors: obesity, female sex, certain medications (tetracycline, vitamin A, steroids)

8. Arnold-Chiari Type I Malformation

• Cerebellar tonsillar herniation through the foramen magnum
• Classic: occipital headache exacerbated by Valsalva maneuver (coughing, straining, sneezing)
• Associated with syringomyelia (~90% association)
• May have lower cranial nerve signs, myelopathic signs

9. Vertebral Artery Dissection

• Important to exclude in new or changing occipital/posterior neck pain
• Presents with dizziness/vertigo (58%), headache (51-65%), neck pain (46-66%)
• Can progress to ischemic stroke (lateral medullary/cerebellar syndromes)
• More common after neck trauma, chiropractic manipulation, or spontaneously in young adults
• Requires urgent MRI/MRA

10. Hypertensive Headache

• Severe hypertension (usually >180/120 mmHg - hypertensive emergency) can cause occipital headache
• Typically bilateral, pulsating, and morning-predominant
• Also: tyramine reaction (MAO inhibitor interaction) - hallmark is severe occipital or temporal headache with hypertension, diaphoresis, neck stiffness

11. Atlanto-Axial Joint Disease / Rheumatoid Arthritis

• Cervical spine involvement at C1-C2 (especially in RA or ankylosing spondylitis) causes occipital pain
• Risk of atlanto-axial subluxation - serious red flag

12. Suboccipital Muscle Tension / Myofascial Pain

• Tight, tender suboccipital muscles from poor posture (forward head posture), screen time, stress
• Often associated with upper trapezius trigger points
• Referred pain pattern mimics tension headache

Summary Table

Approach to the Patient

1. History: onset, character (stabbing vs. pressing vs. pulsating), radiation, triggers (neck movement, Valsalva, posture), associated symptoms (nausea, visual changes, tinnitus, weakness), trauma history, medications
2. Examination: BP, fundoscopy (papilledema), cervical range of motion, occipital nerve palpation, neurological exam
3. Red flags requiring urgent imaging (MRI brain/cervical spine, MRA):

• Progressive worsening
• Nocturnal or early morning headache
• New neurological signs
• Papilledema
• Triggered by Valsalva (cough, strain)
• Fever + meningismus
• Age >50, new headache

1. Diagnostic nerve block: Greater occipital nerve block is both diagnostic (confirms occipital neuralgia/cervicogenic etiology) and therapeutic