Occipital neuralgia

Occipital neuralgia, also known as C2 neuralgia or, rarely, Arnold's neuralgia, is a medical condition characterized by chronic pain in the upper neck, back of the head and behind the eyes. These areas correspond to the locations of the lesser and greater occipital nerves. Wrapped around the greater occipital nerve is the occipital artery, which can contribute to the neuralgia. The condition is also sometimes characterized by diminished sensation in the affected area.

Causes

Occipital neuralgia is caused by damage to the occipital nerves, which can arise from trauma (usually concussive), physical stress on the nerve, repetitive neck contraction, flexion or extension, or as a result of medical complications (such as osteochondroma, a benign bone tumour). A rare cause is a cerebrospinal fluid leak.^[3] Another is radio frequency nerve ablation. 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]

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

Symptoms

The main symptom of occipital neuralgia is chronic headache. The pain is commonly localized in the back and around or over the top of the head, sometimes up to the eyebrow or behind the eye. Because chronic headaches are a common symptom of numerous conditions, occipital neuralgia is often misdiagnosed at first, most commonly as tension headaches or migraines, leading to unsuccessful treatment attempts. Another symptom is sensitivity to light, especially when headaches occur.

Occipital neuralgia is characterized by severe pain that begins in the upper neck and back of the head. This pain is typically one-sided, although it can be on both sides if both occipital nerves have been affected. Additionally, the pain may radiate forward toward the eye as it follows the path of the occipital nerve(s). Individuals may notice blurred vision as the pain radiates near or behind the eye. The pain is commonly described as sharp, shooting, zapping, an electric shock, or stabbing. The bouts of pain are rarely consistent, but can occur frequently depending on the damage to the nerves. The amount of time the pain lasts typically varies each time the symptom appears; it may last a few seconds or be almost continuous. Occipital neuralgia can last for hours or for several days.

Other symptoms of occipital neuralgia may include:

• Aching, burning, and throbbing pain that typically starts at the base of the head and radiates to the scalp
• Pain on one or both sides of the head
• Pain behind the eye
• Sensitivity to light
• Sensitivity to sound
• Slurred speech
• Pain when moving the neck
• Difficulty with balance and coordination
• Tender scalp
• Nausea and/or vomiting

Treatment

There are a wide range of other non-invasive treatments, including physical therapy, rest, heat, anti-inflammatory medication, antidepressants, anti-convulsants, opioid and non-opioid analgesics, and migraine prophylaxis medication. Other alternatives include local nerve block, peripheral nerve stimulation, steroids, rhizotomy, phenol injections, and occipital cryoneurolysis. Other less common forms of surgical neurolysis or microdecompression are also used to treat the condition when conservative measures fail.

References

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 gastic 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

External links

• Occipital Neuralgia at NINDS