Overview
Occipital neuralgia refers to the pain in the distribution area of the large and small occipital nerves in the posterior head. The posterior occipital and cervical sensation is innervated by the 1st, 2nd and 3rd pairs of cervical nerves. The posterior branch of the 2nd cervical nerve constitutes the greater occipital nerve, which emerges superficially from the deep tissue at the midpoint of the line connecting the mastoid process and the midpoint behind the 1st cervical vertebra, and is distributed in the posterior occipital area equivalent to the part of the external auditory canal on both sides after the cephalocervical line. The anterior branch of the 3rd cervical nerve constitutes the lesser occipital nerve and the greater auricular nerve. The small occipital nerve is mainly distributed in the upper part of the auricle and the skin of the lateral occipital area, while the large auricular nerve is mainly distributed in the front and back of the lower part of the auricle, the surface of the parotid gland and the angle of the mandible. When the three nerves are involved, they can cause pain in the posterior occipital and cervical regions and often appear as neuralgia. Because the posterior roots of the 1st cervical nerve are generally very small in development, posterior occipital and neck pain caused by spinal nerve disease in the upper cervical segment is collectively referred to as occipital neuralgia.
The disease occurs mostly in adults, and a proportion of patients have a more definite etiology: 1.
1, certain diseases such as upper respiratory tract infection or the presence of infectious lesions in the nasopharynx, or after exposure to cold and moisture, can cause inflammatory lesions in the occipital nerve and cause pain.
2. Mostly, occipital neuralgia is caused by edema, degeneration or demyelinating lesions of the occipital nerve due to local or systemic diseases.
①Cervical spine disease: It is a more common cause and may be related to the compression of the nerve in the upper cervical segment by the hyperplastic bone. Upper cervical spine tuberculosis, rheumatoid spondylitis or metastatic cancer may also cause occasionally.
②Spinal canal diseases: spinal cord tumor in the upper cervical segment, adhesive arachnoiditis, and spinal cord cavitation can cause cervico-occipital pain.
③Atlanto-occipital deformity: skull base entrapment, atlanto-occipital joint fusion, upper cervical vertebral body separation insufficiency, occipital foramen stenosis, etc., mainly due to compression and traction on the spinal nerve of the upper cervical segment.
④Posterior cranial fossa lesions: such as posterior cranial fossa tumor, posterior cranial fossa arachnoiditis, etc. can also cause occipital and neck pain.
⑤ Injury: suboccipital joint ligament injury, anterior and posterior atlantoaxial arch fracture, atlantoaxial subluxation, cervical spine and soft tissue injury of the neck, etc.
(6) Systemic diseases: diabetes, rheumatism, malaria, uremia, arteriosclerosis, organophosphorus poisoning, long-term alcohol consumption, etc. can cause degenerative lesions of the occipital nerve.
Clinical manifestations
Occipital neuralgia is pain under the occipital bone and the back of the head, which can also be spontaneous or induced by head and neck movements, sneezing, coughing, etc. Patients often keep their heads still during attacks, with a mild forward and lateral tilt. The pain is often persistent and may increase paroxysmally, but there may be a dull pain in the occipital region between attacks. The pain begins in the suboccipital region and radiates to the posterior scalp, and may be exacerbated by compression of the occipital nerve. Severe pain may be accompanied by posterior ophthalmoplegia. Migraine-like symptoms or autonomic symptoms of cluster headache may be present. A significant proportion of patients with myotonic headaches have headaches located in similar areas. On examination, pressure points of the occipital nerve can be found. The pressure point for the greater occipital nerve is located at the midpoint of the line connecting the mastoid process to the back of the 1st cervical vertebra (Fengchi point), and the pressure point for the lesser occipital nerve is located at the posterior superior edge of the attachment point of the sternocleidomastoid muscle (Fu Ming point). When pressure is applied to these areas, the patient can feel severe pain, which can spread along the nerve distribution. The skin of the occipital region is often hyperalgesic or painful to the touch.
Diagnostic points]
The main points of diagnosis of occipital neuralgia are as follows.
1. The patient has the above-mentioned pain characteristics.
2.The innervation area is hyperalgesic.
3. On examination, there is pressure pain and radiating pain at the involved nerve and the ipsilateral 2nd and 3rd cervical transverse processes.
4.Head and neck movements may be the trigger.
5.The pain disappears after occipital nerve block.
The occipital nerve must be differentiated from occipital pain originating from the atlantoaxial joint or the supraspinal synovial joint, or from the trigger point of the cervical muscle attachment point.
[Treatment plan and principles
1. Etiological treatment
For patients with structural damage, etiological treatment should be carried out as far as possible, such as surgical removal of the tumor and release of compression, and treatment for various infections of influenza, etc.
2.Drug treatment
(1) Analgesic drugs: such as carbamazepine, ibuprofen, phenytoin sodium, etc. Carbamazepine mainly works due to blocking synaptic transmission, the dosage is 100mg/dose, 3 times a day, it is appropriate to start with a small amount. Phenytoin sodium 0,1g/dose, 3 times daily, this drug was considered to be the first choice for occipital neuralgia before the application of carbamazepine, and its pharmacological effect is similar to that of carbamazepine.
(2) neurotropic agents: a large number of B vitamins, especially vitamin B12 has analgesic effect and can promote the repair of nerves, vitamin B1100mg + vitamin B12 500-1000μg intramuscular injection, once a day.
(3) Adrenocorticotropic hormone: It has the effect of reducing neuroedema and relieving pain. Dexamethasone 1,5mg/d, prednisone 15-30mg/d, can be applied for 5-7 days.
3.Local physiotherapy Intermittent current, ultra-short wave, ultraviolet light or procaine iontophoresis can be used in the acute stage; ultra-short wave, short wave heat transmission or iodine iontophoresis are suitable in the chronic stage.
4.Acupuncture treatment Commonly used acupuncture points include Fengchi, Cataract, Houxi, Hegu, Waiguan, Taichong, Kunlun, etc.
5.Nerve block therapy If general treatment is ineffective, local nerve block therapy is feasible.
(1) Occipital nerve block: The puncture point of occipital nerve block is at the midpoint of the line between the affected mastoid process and the second cervical spinal process or 2 or 5 cm below the posterior occipital bulge, where there is often pressure pain. The tip of the puncture needle avoids the occipital artery and is inserted subcutaneously at the puncture point, then the tip of the puncture needle is advanced slowly at an angle of about 45° upward, and 2 to 3 ml of 1% lidocaine is injected when the patient has radiating pain. 1 to 2 ml of nerve-disrupting drug is also injected after numbness. the puncture point of the occipital lesser nerve block is 2 or 5 cm outside the puncture point of the greater occipital nerve block. For those with inflammatory factors, glucocorticoids can be added to the local anesthetic, and vitamin B can also be added. For repeated blocks that are ineffective, the application of nerve-destroying drugs, such as anhydrous ethanol or 10% to 15% phenol glycerol block, can be considered.
(2) C2~4 intervertebral foraminal block: reversible block, with the same drug as above, no more than 4ml per site, with discretionary dosage for multi-site block, avoiding simultaneous bilateral block.
6.Surgical treatment For individual patients with severe pain, if the effect of block therapy is not lasting, subfascial resection of peripheral nerve trunks such as occipital greater or occipital lesser nerve can also be considered.