Occipital neuralgia is a headache disorder caused by injury or inflammation of the occipital nerves, which are peripheral branches of the C2 and C3 spinal nerves. It causes paroxysmal severe pain in the distribution of the greater occipital nerve (GON), lesser occipital nerve (LON), and third occipital nerve (TON).
Epidemiologically, a Dutch study reported an incidence of 3.2 per 100,000 person-years, with no clear sex difference. Some reports indicate a prevalence of 1.2%, while other studies suggest women account for 80% of cases3). In a survey at a headache specialty clinic, 25% of 800 headache patients met the criteria for occipital neuralgia, while 85% had other coexisting headache types7).
Approximately 90% of cases involve the GON2). Because pain can radiate as referred pain to the ipsilateral retro-orbital region, many patients visit ophthalmologists.
Pain in the GON region may radiate to the ipsilateral deep eye area, causing referred pain. Some patients visit an ophthalmologist complaining of deep eye pain even though the eye itself is normal.
The pain of occipital neuralgia is paroxysmal and has characteristic features.
Attacks last from seconds to minutes, and may be accompanied by dull pain between episodes. When chronic, attacks recur and can significantly interfere with daily life.
The following findings are observed during examination.
The main cause of occipital neuralgia is irritation or compression of the cervical nerves in the C2 and C3 regions. Although many cases are considered idiopathic, the following causes are known.
The diagnostic criteria of the International Headache Society (ICHD-3) consist of the following four items2).
GON block is an essential procedure for definitive diagnosis. However, caution is needed because up to 40% of migraine and cluster headache cases show false positives. To increase reliability, a second block may be performed.
Under ultrasound guidance, the GON is identified between the obliquus capitis inferior and semispinalis capitis muscles. An example of the medication used is a mixture of 1 mL of methylprednisolone 40 mg/mL and 2 mL of 0.5% bupivacaine 3).
Pain relief from nerve block strongly supports the diagnosis, but up to 40% of migraine and cluster headache cases show false positives. For a more certain diagnosis, a second block may be performed. It is important to make a comprehensive judgment based on other criteria.
It is important to differentiate from the following diseases.
| Differential Disease | Key Points for Differentiation |
|---|---|
| Cervicogenic Headache | Caused by lesions within the cervical spine. Differentiated by GON block. |
| Migraine | Pulsating, associated with nausea. Distribution differs. |
| Cluster headache | Severe pain around the orbit. Accompanied by autonomic symptoms. |
| Herpes zoster | Confirmed by skin rash and varicella-zoster virus antibody titer5) |
Initial treatment begins with a conservative approach.
Ultrasound-Guided GON Block
Efficacy: Significantly improves frequency and severity of occipital headaches at 6 weeks and 6 months. Pain severity improves by 40–45% 7).
Duration of effect: Some cases have shown effects lasting 2 years after a single block 3).
Accuracy: Improved duration of effect compared to traditional landmark methods 7).
Botulinum Toxin (BOT-A)
Mechanism: Suppression of substance P and glutamate, reduction of central sensitization.
Effect: Greater pain improvement at 6 months compared to anesthetic block 7).
A procedure that reduces abnormal nerve signals to control pain. It induces tissue changes via an electric field. In a report by Cohen et al., PRF provided greater reduction in occipital headache at 6 weeks compared to steroid injections, but the effect diminished at 3 months 2).
Surgical treatment is a last resort when conservative therapy, injections, and medication management have all failed.
A definitive cure has not been established, but symptom relief is possible through a stepwise approach. Surgery is a last resort, and in ONS, pain reduction is achieved in 72–89% of adults 1). However, it also carries risks of infection and pain worsening.
The central pathology of occipital neuralgia is entrapment or compression due to the complex course of the GON. The GON originates from the posterior ramus of C2, winds around the inferior oblique capitis muscle, and ascends between the semispinalis capitis and inferior oblique capitis muscles. It then pierces the semispinalis capitis and upper trapezius muscles to reach the subcutaneous layer of the occipital region. Fascial compression along this piercing pathway is the main cause of neuropathic pain 4)7).
Lesions of the dorsal root entry zone (DREZ) are also associated with the development of occipital neuralgia. In C2 spinal cord infarction, vasogenic edema occurs in the DREZ, inducing transient occipital neuralgia 6).
The trigeminocervical complex (TCC) is an important anatomical concept. The caudal subnucleus of the spinal trigeminal nucleus is anatomically continuous with the upper cervical dorsal horn, and stimulation of the GON can cause central sensitization of the first division of the trigeminal nerve 5). Animal experiments have also confirmed that stimulation of the GON region induces central sensitization of afferent fibers of the first division of the trigeminal nerve.
Through this mechanism, ipsilateral occipital neuralgia may develop secondarily from trigeminal herpes zoster. Crosstalk via the TCC is presumed, and a case of complete remission with valacyclovir 3000 mg/day for 7 days has been reported 5).
Two types of hydrodissection techniques have been reported as procedures to physically separate nerves from surrounding tissues.
Lam et al. (2024) performed ultrasound-guided GON hydrodissection using 20 mL of D5W in two cases7). Case 1 (45-year-old woman, 18 months of occipital neuralgia) used a lateral decubitus approach, with NRS 8→0/10, sustained 0–1/10 for 6 months, and NDI (Neck Disability Index) 20→4/50 (80% improvement). Case 2 (50-year-old woman, suboccipital pain for 1 year) used a craniocaudal approach, with NRS 9→1/10, sustained for 6 months.
The mechanisms of analgesia with D5W include the glycopenic hypothesis (removal of glucose from C fibers increases firing rate by 650%, normalized by D5W administration), analgesia via substance P release activating ASIC1a, and anti-inflammatory effects through reduction of IL-6 and IL-1β7).
Kaga (2022) reported the world’s first case of fascial hydrodissection for occipital neuralgia in an 81-year-old woman4). 5 mL of 0.75% ropivacaine was injected between the semispinalis capitis and obliquus capitis inferior muscles, and 9 mL of saline plus 1 mL of 1% lidocaine was injected into the deep layer of the sternocleidomastoid muscle. NRS decreased from 10 to 0 immediately after the procedure. Analgesics were discontinued after 23 days, and no recurrence occurred during the 4-week follow-up period. The use of low-dose anesthetics (9 mL saline + 1 mL lidocaine) kept the risk of local anesthetic toxicity extremely low.
Mossner et al. (2024) performed trial or permanent implantation of ONS in three children (aged 15–17 years) with refractory occipital neuralgia1). All cases showed significant pain reduction (VAS 9–10 to 0–1/10, p=0.002) with no complications. One patient remained pain-free for 15 months after the trial and declined permanent implantation. Reports of ONS specifically for pediatric occipital neuralgia are scarce in the literature, making these findings valuable. Regarding surgical GON decompression/neurectomy in children, Villeneuve et al. reported pain improvement from VAS 8.3 to 1 in six adolescents, but all developed sensory abnormalities1).
Xu & Yin (2024) performed 6 sessions of acupuncture (over 12 days) on a 76-year-old man with refractory occipital neuralgia of 10 years’ duration 2). The S-LANSS (Leeds Assessment of Neuropathic Symptoms and Signs) score decreased from 14 to 0, with no recurrence at 3 months; only mild headaches 1–2 times per month remained at 9 months. The analgesic mechanism is suggested to involve endorphin release, mast cell degranulation, and the vagus nerve-TNF-α signaling pathway.
