Occipital neuralgia is a headache disorder that presents with pain in the distribution of the occipital nerves. A recent update to diagnostic criteria may aid in defining true prevalence and optimizing recognition and treatment. Physical examination and diagnostic blocks remain the standard for diagnosis. Multiple treatment options exist, including rehabilitative measures, conservative modalities, pharmaceutic management, both invasive and noninvasive nerve stimulators, and surgery. More research is warranted to best guide clinical approach.
KeywordsCervicogenic headache, C2 neuralgia, occipital neuralgia, rehabilitation, headache disorder
|G44.89||Other specified headache syndromes|
The International Classification of Headache Disorders-third edition (ICHD-3) beta diagnostic criteria for occipital neuralgia are as follows :
Unilateral or bilateral pain with criteria 2 to 5
Located in the distribution of any and/or all of the occipital nerves ( Fig. 106.1 )
Characterized by at least two of the following:
paroxysmal recurrence lasting seconds to minutes
Pain quality is described as shooting, stabbing, or sharp
Pain is associated with dysesthesia and/or allodynia with scalp stimulation and either or both of the following:
tenderness over the nerve pathway and/or
trigger points in the region of the greater occipital nerve distribution of C2
Relieved by anesthetic block of the nerve.
Not better accounted for by another ICHD-3 diagnosis.
Although etiology of occipital neuralgia can be broad, most cases are idiopathic and have no discernible lesions. Potential causes include myofascial tightening of the upper cervical spine muscles, trauma of C2 nerve root (whiplash injury), prior skull or suboccipital surgery, other type of nerve entrapment, hypertrophied atlantoepistrophic (C1-C2) ligament, sustained neck muscle contractions, vasculopathies, mass lesions, and spondylosis of the cervical facet joints. Other rare causes of occipital neuralgia reported in the literature include upper respiratory tract infection, herpes zoster infection or postherpetic neuralgia, C2 myelitis, hypermobile C1 vertebra, and giant cell arteritis.
Unfortunately, true incidence of occipital neuralgia is not yet known, and may be confounded by misdiagnosis or lack of patient report.
The greater occipital nerve innervates the posterior skull from the suboccipital area to the vertex. It is formed from the medial (sensory) branch of the posterior division of the second cervical nerve. It emerges between the atlas and lamina of the axis below the oblique inferior muscle and then ascends obliquely on this muscle between it and the semispinalis muscle. The course of the greater occipital nerve does not appear to differ in men and women.
The lesser occipital nerve forms from the medial (sensory) branch of the posterior division of the third cervical nerve, ascends like the greater occipital nerve, and pierces the splenius capitis and trapezius muscles just medial to the greater occipital nerve. It ascends along the scalp to reach the vertex, where it provides sensory fibers to the area of the scalp lateral to the greater occipital nerve.
The roots of the first two cervical nerves are not protected posteriorly by pedicles and facets because of the unique articulation of the atlas and axis relative to the rest of the spinal column. Thus the first two cervical nerves are relatively vulnerable to injury. The joint between the atlas and occiput, between which the first cervical nerve emerges, is relatively immobile compared with the lower C1-C2 articulation. Thus the C2 nerve root emerges unprotected through a highly mobile joint, and this may explain the predominance of greater occipital nerve involvement in occipital neuralgia.
Symptomatology of occipital neuralgia is consistent with the ICHD-3 diagnostic criteria, but variations can be seen due to several neuronal connections that can cause retro-orbital pain, tinnitus, visual disturbances, and dizziness, for example. Severe ocular pain has also been described and attributed to convergence of sensory input from the upper cervical nerve roots into the trigeminal nucleus.
Occipital neuralgia may occur in combination with other types of headaches. For example, one study found concurrent migraine in 20 of 35 consecutive patients presenting with occipital neuralgia. It is also important to note the diagnostic challenge secondary to the many similarities that exist between occipital neuralgia and migraine headache, including presentation with paroxysmal pain, allodynia, occipital tenderness, and even demonstration of therapeutic response from nerve block.
On examination, pain is generally reproduced by palpation of the greater and lesser occipital nerves. Allodynia or hyperalgesia may be present in the nerve distribution. Myofascial pain may be present in the neck or shoulders. Pain may limit cervical range of motion. Neurologic examination findings of the head, neck, and upper extremities are generally normal.
Entrapment of the nerve near the cervical spine may result in increased symptoms during flexion, extension, or rotation of the head and neck. Compression of the skull on the neck (Spurling maneuver), especially with extension and rotation of the neck to the affected side, may reproduce or increase the patient’s pain if cervical degenerative disease is the cause of the neuralgia. Pressure over both the occipital nerves along their course in the neck and occiput or pressure on the C2-C3 facet joints should cause an exacerbation of pain in such patients, at least when the headache is present. Even if the actual pathologic process is in the cervical spine, tenderness over the occipital nerve at the superior nuchal line is usually present.
In general, there are no neurologic deficits from occipital neuralgia. However, the pain from this entity may result in significant limitations in activities of daily living. During exacerbations, patients may have significant functional limitations, including insomnia, loss of work time, and inability to perform physical activity or to drive a vehicle. Tasks that involve the cervical spine or upper extremities, such as talking on the telephone, working at the computer, reading a book, cooking, gardening, and driving, may be painful and limited.
The diagnosis of occipital neuralgia can be made clinically on the basis of history and physical examination and by utilizing ICHD-3 diagnostic criteria. Diagnostic local anesthetic nerve blocks may be done with or without the addition of a corticosteroid. It is also imperative that the symptoms exhibited are not better accounted for by a different diagnosis.
Radiographs may be obtained to rule out gross abnormalities as an initial screening test but will not generally provide the level of detail needed for diagnostic purposes. Radiologic degenerative changes of the cervical spine do not necessarily correlate with the patient’s symptoms and examination findings, but C2-C3 arthritic changes in the absence of other gross or radiographic abnormalities may explain the etiology. Magnetic resonance imaging or computed tomography of the cervical spine will aid to rule out anatomic cause such as tumor, vascular malformation, infection, or spondylotic arthritis that may be compressing the medial (sensory) branches of C2-C3. Single-photon emission computed tomography and positron emission tomography are occasionally used for diagnosis and treatment of certain headache syndromes and may be useful in occipital neuralgia if there is functional pathologic change involved or in trying to distinguish between occipital neuralgia and cluster or migraine headache.
Finally, the use of ultrasound in assisting diagnosis is becoming increasingly prevalent, as it is cost-effective and can be performed in office. Through this method, a practitioner may be able to directly visualize: (1) entrapment of the nerve within the suboccipital muscles, within vasculature, or by a mass lesion; (2) enlargement of the cross-sectional area of the greater occipital nerve, which typically is 2.0 ± 0.1 mm 2 ; or (3) direct injury to the nerve itself.
C2-C3 subluxation or arthropathy
Congenital or acquired abnormalities at the craniocervical junction (e.g., Arnold-Chiari malformation or basilar invagination)
Giant cell arteritis
Herpes zoster or postherpetic neuralgia
Tumor (e.g., posterior fossa)
The key component of management is to provide education, support, and reassurance about occipital neuralgia and the treatment plan. A conservative approach for initial treatment may include heat or cold therapy, massage, education on maintaining good posture, avoidance of excessive cervical spine flexion-extension or rotation, physical therapy, acupuncture, and/or application of transcutaneous electrical nerve stimulation.
Although more research is needed into the efficacy of pharmacologic therapy for occipital neuralgia, consideration can be given to treatment with nonsteroidal anti-inflammatory drugs, acetaminophen, tricyclic antidepressants, anticonvulsants, and muscle relaxants.
The incorporation of stretching and strengthening exercises for the paracervical and periscapular muscles may be appropriate for the patient with subacute or chronic occipital neuralgia, particularly if the condition is provoked by cervical spine or trunk movement. Postural training and relaxation exercises should be incorporated into the exercise regimen. Principles of ergonomics should be addressed if work site activity is limited by pain exacerbations (e.g., use of a telephone headset, document holder).
Manual therapy, including spinal manipulation and spinal mobilization, has been used to treat patients with cervicogenic headaches. A review of trials done with spinal manipulation for cervicogenic headache revealed two with positive results regarding headache intensity, headache duration, and medication intake. Only one trial showed a decrease in headache frequency. There is a need for randomized controlled trials to evaluate these therapies. Any spinal manipulation should be done with caution because there are serious risks if it is improperly performed. Anecdotal reports support a trial of cervical traction in some cases.
Blockade of the greater or lesser occipital nerve with a local anesthetic is diagnostic and therapeutic ( Fig. 106.2 ). Pain relief can vary from hours to months. In general, at least 50% of patients will experience more than 1 week of relief after one injection. Isolated pain relief for more than 17 months has been reported after a series of five blocks. The addition of a cortisone preparation is controversial, but it may provide additional benefit.