Cervicogenic Headache – A Frequently Missed Diagnosis

Dr Ho Kok Yuen, Consultant Anaesthetist and Pain Specialist, Pain Management Centre, Singapore General Hospital

Mr N is a 40 year-old man who has been suffering from persistent right-sided headache for more than ten years. The headache was so severe that it disrupted his sleep every night and he was also frequently absent from work. Numerous doctors told him that he has migraine headaches. However, his headaches did not improve despite taking various medications for migraine. Another patient, Madam B, 56, was also diagnosed with migraine headaches. Her pain was localised to the left temporal and occipital region as well as the left side of the neck. Similarly, anti-migraine therapy did not help alleviate her symptoms.

These two patients sought treatment at the Singapore General Hospital (SGH) Pain Management Centre. Their symptoms were suggestive of cervicogenic headache. Both patients subsequently received a series of local anaesthetic and steroid injections into the cervical facet joints with almost complete relief of their headaches.

Causes

Cervicogenic headache is a form of headache resulting from abnormalities in the bony structures or soft tissues of the neck. The prevalence of cervicogenic headache in the general population ranges between 0.4% and 2.5%, and it is four times more prevalent in women.

It commonly occurs after head or neck injury but may also occur in the absence of trauma. The diagnosis is frequently missed or underdiagnosed by doctors because the clinical features of cervicogenic headache mimic common headache disorders such as tension-type headache, migraine etc.

One of the common causes for cervicogenic headache is whiplash injury occurring after a motor vehicle accident, where bones, intervertebral discs, ligaments and muscles sustain significant trauma. Another common cause is cervical spondylosis, or degeneration occurring in the facet joints – a condition also known as facet joint arthritis.

Pathophysiology

The pathophysiology of cervicogenic headache has been debated, but the pain is likely referred from one or more muscular, neurogenic, osseous, articular, or vascular structures in the neck.

The trigeminocervical nucleus is a region of the upper cervical spinal cord where sensory nerve fibres in the descending tract of the trigeminal nerve (trigeminal nucleus caudalis) are believed to interact with sensory fibres from the upper cervical nerve roots. This functional convergence of upper cervical and trigeminal sensory pathways allows the bidirectional referral of painful sensations between the neck and trigeminal sensory receptive fields of the face and head.

Diagnosis

A complete history and careful physical examination will usually help in making a diagnosis of cervicogenic headache (Table 1). The Cervicogenic Headache International Study Group has also developed diagnostic criteria for this condition.

History and Physical Examination Unilateral head or face pain without sideshift; the pain may occasionally be bilateral Pain localised to the occipital, frontal, temporal or orbital regions Moderate to severe pain intensity Intermittent attacks of pain lasting hours to days, constant pain or constant pain with superimposed attacks of pain Pain is generally deep and non-throbbing Headache is triggered by neck movement, sustained or awkward neck postures; digital pressure to the suboccipital, C2, C3 or C4 regions or over the greater occipital nerve Restricted active and passive neck range of motion; neck stiffness Table 1

Patients typically have headache that is triggered by active and passive neck movements, especially in extension or extension with rotation toward the side of pain, or on applying pressure over the involved facet joint region. Trigger points within the suboccipital or cervicothoracic musculature may also be present. More importantly, signs and symptoms of cervical radiculopathy are absent.

Imaging studies including plain radiography, computed tomography (CT) and magnetic resonance imaging (MRI) cannot confirm the diagnosis of cervicogenic headache. However, imaging is still essential to exclude other serious causes of headache including brain or spinal tumours, arteriovenous malformation, herniated intervertebral discs etc. Laboratory tests may be indicated to exclude systemic diseases such as rheumatoid arthritis, systemic lupus erythematosus or primary muscle diseases.

Cervical facet joint injection or cervical medial branch block is used to confirm the diagnosis of cervicogenic headache. The first three cervical spinal nerves and their medial branches are the primary peripheral nerve structures that can refer pain to the head. Such diagnostic anaesthetic blocks are commonly performed under fluoroscopy at the SGH Pain Management Centre.

Treatment

Successful treatment of cervicogenic headache usually requires a multimodal approach involving pharmacological, nonpharmacological, interventional and rarely, surgical treatment.

Simple analgesics such as paracetamol, non-steroidal antiinflammatory drugs (NSAIDs), cyclo-oxygenase-2 (COX-2) inhibitors may be used for intermittent pain attacks. Migraine-specific abortive medications such as ergot derivatives or triptans are not effective for cervicogenic headache. In some patients with predominant neuropathic features involving the head and neck area, tricyclic antidepressants, anticonvulsants and serotonin noradrenergic reuptake inhibitors (SNRIs) may be prescribed. The use of muscle relaxants and the injection of Botulinum toxin A into muscles have been reported but further scientific evidence is needed to confirm their efficacy. Opioid analgesics are generally not recommended for long-term management of cervicogenic headache.

Physical therapy including strengthening exercises, stretching and muscle conditioning programme are important modalities for prevention as well as control of cervicogenic headaches.

Injection of small amounts of local anaesthetic and steroids into the arthritic facet joints in the cervical spine is another treatment option available. If such diagnostic blocks are successful in providing substantial but temporary pain relief, radiofrequency thermoablation of the cervical medial branch nerves can be offered to patients to extend the duration of pain relief to 12-18 months. Radiofrequency thermoablation uses high heat at a  needle tip to destroy nerves that supply the affected facet joints  in the neck.  By doing so, the painful facet joints are denervated and pain signals from these joints are interrupted.

Cervical facet joint block performed under flouroscopy

Surgical transection of the greater occipital nerve or occipital nerve decompression from “entrapment” within the trapezius muscle has been reported with only short-term pain relief. More recently, implantation of percutaneous leads for occipital nerve stimulation has also been reported to provide good efficacy but data is limited.

Conclusion

The presenting symptom complex of cervicogenic headache is similar to that of the more commonly encountered primary headache disorders such as migraine or tension-type headache. It is a relatively common cause of chronic headache that is often misdiagnosed or unrecognised. Primary care physicians should consider this condition in patients with headaches that persist despite adequate therapy. Early diagnosis and management through a comprehensive, multidisciplinary pain treatment program can significantly decrease disability and improve function and quality of lives of patients.

References

1. Biondi DM. JAOA 2005;105:16-22.
2. Bogduk N. J Manipulative Physiol Ther 1992;15:67-70.
3. Sjaastad O, Fredriksen TA, Pfaffenrath V. Headache 1998;38:442-445.

The Pain Management Centre at Singapore General Hospital can manage various types of somatic and neuropathic pain problems, including :  Cancer-related pain Back and neck pain Orofacial pain Myofascial pain and Fibromyalgia Neuropathic pain syndrome   - Trigeminal neuralgia   - Peripheral neuropathy   - Diabetic peripheral neuropathy Complex regional pain syndromes Post surgical pain syndromes Post injury chronic pain Central pain Spasticity

Need indepth information ? Access our Conditions & Treatments sections for related topics on Cancer Pain, Chronic Post-surgical Pain, Facet Joint Syndrome and Treatment, Low Back Pain, Neck Pain and Sacroiliac Joint Pain and Treatment.