Occipital neuralgia

Occipital neuralgia (ON) is a painful condition affecting the posterior head in the distributions of the greater occipital nerve (GON), lesser occipital nerve (LON), third occipital nerve (TON), or a combination of the three. It is paroxysmal, lasting from seconds to minutes, and often consists of lancinating pain that directly results from the pathology of one of these nerves. It is paramount that physicians understand the differential diagnosis for this condition and specific diagnostic criteria. There are multiple treatment modalities, several of which have well-established efficacy in treating this condition.[1]

Occipital neuralgia
Other namesC2 neuralgia, Arnold's neuralgia
SpecialtyNeurology

Signs and symptoms

Patients presenting with a headache originating at the posterior skull base should be evaluated for ON. This condition typically presents as a paroxysmal, lancinating or stabbing pain lasting from seconds to minutes, and therefore a continuous, aching pain likely indicates a different diagnosis. Bilateral symptoms are present in one-third of cases.[1]

Causes

Occipital neuralgia is caused by damage to the occipital nerves, which can arise from trauma (usually concussive or cervical), physical stress on the nerve, repetitive neck contraction, flexion or extension, and/or as a result of medical complications (such as osteochondroma, a benign bone tumour). A rare cause is a cerebrospinal fluid leak.[2] [3] Rarely, occipital neuralgia may be a symptom of metastasis of certain cancers to the spine.[4] Among other cranial neuropathies, occipital neuralgia is also known to occur in patients with multiple sclerosis.[5] Hodgkins and other cancer survivors who have had radiation treatment to the neck also can develop this, sometimes many years later.

There are several areas that have the potential to cause injury from compression:

  1. The space between the C1 and C2 vertebrae
  2. The atlantoaxial ligament as the dorsal ramus emerges
  3. The deep to superficial turn around the inferiolateral border of the obliquus capitis inferior muscle and its tight investing fascia
  4. The deep side of semispinalis capitis, where initial piercing can involve entrapment in either the muscle itself or surrounding fascia
  5. The superficial side of semispinalis capitis, where completion of nerve piercing muscle and its fascia again poses risk
  6. The deep side of the trapezius as the nerve enters the muscle
  7. The tendinous insertion of the trapezius at the superior nuchal line
  8. The neurovascular intertwining of the greater occipital nerve and the occipital artery

Diagnosis

The diagnosis is established clinically through characteristic symptoms (mostly short attacks of an intense sharp, piercing or electrifying pain with propagation along the occipital nerve from the lateral neck and under/behind the ear towards the side of the head and the eye, with often longer lasting background pain) and sometimes supporting clinical features.

Differential diagnosis

The conditions most easily mistaken with ON for other headache and facial pain disorders include migraine, cluster headache, tension headache, and hemicrania continua. Mechanical neck pain from an upper disc, facet, or musculoligamentous sources may refer to the occiput, but is not classically lancinating or otherwise neuropathic and should not be confused with ON. A crucial step in differentiating ON from other disorders is relief with an occipital nerve block.[1]

Epidemiology

In one study investigating the incidence of facial pain in a Dutch population, ON comprised 8.3% of facial pain cases. The total incidence of ON was 3.2 per 100,000 people, with a mean age of diagnosis of 54.1 years.[1]

Treatment

There are multiple treatment options for ON. The most conservative treatments, such as immobilization of the neck by the cervical collar, physiotherapy, and cryotherapy have not been shown to perform better than placebo. Non-steroidal anti-inflammatory drugs, tricyclic antidepressants, serotonin-norepinephrine reuptake inhibitors, and anticonvulsants may help to alleviate symptoms. Following diagnostic nerve blocks, therapeutic blocks may be attempted. Typically, a steroid is added to the local anesthetic with variable results. Botulinum Toxin A injection has emerged as a treatment with a conceptually lower side effect profile than many other techniques described here, with most recent trials demonstrating 50% or more improvement.[1]

It remains a common practice to utilize a landmark-only approach when performing greater and lesser occipital nerve blocks. For blockade of both nerves, medication is infiltrated along the nuchal ridge. This technique, while easy to perform and relatively safe if done correctly, may not be particularly accurate and as a result, could theoretically increase the risk of a false-positive result. To improve accuracy, ultrasound-guided techniques were developed. The original ultrasound-guided technique for injection of the GON (utilized routinely by this article's editor for diagnostic injection and for cryoablation) was described by Greher et al in 2010; it targets the nerve as it courses superficial to the obliquus capitis inferior muscle at the C1-C2 level.[1]

There are several advanced interventional procedures in clinical use:[1]

  • Pulsed or thermal radiofrequency ablation (RFA) may be considered for longer-lasting relief after a local anesthetic blockade confirms the diagnosis. Thermal RFA aimed at destroying the nerve architecture can render long-term analgesia but also comes with the potential risks of hypesthesia, dysesthesia, anesthesia dolorosa, and painful neuroma formation. Chemical neurolysis with alcohol or phenol carries the same risks as thermal RFA. There is no such risk with pulsed RF, however, some question its efficacy as compared to other procedures.
  • Neuromodulation of the occipital nerve(s) involves the placement of nerve stimulator leads in a horizontal or oblique orientation at the base of the skull across where the greater occipital nerve emerges. Patients should be trialed with temporary leads first, and greater than 50% pain relief for several days is considered a successful trial after which permanent implantation may be considered. Risks include surgical site infection and lead or generator displacement or fracture after the operation.
  • Ultrasound-guided percutaneous cryoablation of the GON is commonly performed by the article’s editor. At the correct temperature, there should be stunning but not permanent damage of the nerve, but at temperatures below negative 70 degrees Celsius, nerve injury is possible. Most recently in the literature, a 2018 article by Kastler et al. described 7 patients who underwent cryoneurolysis in a non-blinded fashion to good effect, but the follow-up was limited to 3 months. This editor has seen between 3 months to 1.5 years of benefit (typically around 6 months) with each treatment.
  • Surgical decompression is often considered to be the last resort. In one study of 11 patients, only two patients did not experience significant pain relief postoperatively and mean pain episodes per month decreased from 17.1 to 4.1, with mean pain intensity scores also decreasing from 7.18 to 1.73. Resection of part of the obliquus capitis inferior muscle has shown success in patients who have an exacerbation of their pain with flexion of the cervical spine. Another popular surgical technique is C2 gangliotomy, even though patients are left with several days of intermittent nausea and dizziness. As with any large nerve resection, there is a theoretical risk of developing a deafferentation syndrome, though arguably the risk is lower if the resection is pre-ganglionic.

References
  1. Derek M, Kevin B (2020). "Occipital Neuralgia". Statpearls. PMID 30855865. Text was copied from this source, which is available under a Creative Commons Attribution 4.0 International License.
  2. Ansari, H.; Garza, I. (22 April 2012). "Occipital Neuralgia Secondary to a Spontaneous CSF Leak (P03.218)". Neurology. 78 (Meeting Abstracts 1): P03.218. doi:10.1212/WNL.78.1_MeetingAbstracts.P03.218.
  3. Gazelka, Halena M; Knievel, Sarah; Mauck, W. David; Moeschler, Susan; Pingree, Matthew; Rho, Richard; Lamer, Tim (April 2014). "Incidence of neuropathic pain after radiofrequency denervation of the third occipital nerve". Journal of Pain Research. 7: 195–8. doi:10.2147/JPR.S60925. PMC 3986282. PMID 24748815.
  4. Moulding, HD; Bilsky, MH (March 2010). "Metastases to the craniovertebral junction". Neurosurgery. 66 (3 Suppl): 113–8. doi:10.1227/01.NEU.0000365829.97078.B2. PMID 20173512.
  5. De Santi, L; Annunziata, P (February 2012). "Clin Neurol Neurosurg". Clinical Neurology and Neurosurgery. 114 (2): 101–7. doi:10.1016/j.clineuro.2011.10.044. PMID 22130044. S2CID 3402581.

Frei R. Large study: Frequent nausea worsens migraine severity. Pain Med News 2011;9(8):1– 20.

Liang, H. Occipital Neuralgia as a presenting symptom of gastric cancer metastasis. Imaging in Headache Medicine, April 2012. Saladin, Kenneth S. "Chapter 13: The Spinal Cord, Spinal Nerves, and Somatic Reflexes." Anatomy & Physiology: The Unity of Form and Function. 12th ed. New York, NY: McGraw-Hill, 2012. N. pag. Print.

Stedman, Thomas Lathrop. Stedman's Medical Dictionary—27th Edition Illustrated in Color. 27th ed. Philadelphia: Lippincott Williams & Wilkins, 2000. 1206+. Print.

Williamson et al. The Journal of Headache and Pain 2013, 1(Suppl 1):P65 http://www.thejournalofheadacheandpain.com/content/1/S1/P65

http://www.hopkinsmedicine.org/neurology_neurosurgery/specialty_areas/headache/conditions/occipital_neuralgia.html

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