Neck Tongue Syndrome
Neck-tongue syndrome is a rare condition characterized by pain in the neck associated with numbness of the ipsilateral half of the tongue that is aggravated by movement of the upper cervical spine. This unusual constellation of symptoms is thought to be due to compression of the C2 nerve root by compromise of the atlantoaxial joint.
This compression can be caused by joint instability that allows subluxation of the lateral joint, bony abnormality such as congenital fusions or stenosis, or tubercular infection.
The tongue numbness is thought to be due to damage or intermittent compression of the lingual afferent fibers that pass via the hypoglossal nerve to innervate the tongue.
The bulk of the fibers are proprioceptive, and patients with neck-tongue syndrome also may exhibit pseudoathetosis of the tongue. Neck-tongue syndrome occurs most commonly in patients older than 50 years, although the syndrome has been reported in a few pediatric patients.
What are the Symptoms of Neck Tongue Syndrome
The pain of neck-tongue syndrome is in the distribution of the C2 nerve root. It is intermittent but is reproducible with certain neck movements. The physical findings associated with this pain are ill defined, with some patients with neck-tongue syndrome exhibiting a decreased range of motion of the cervical spine or tenderness of the upper paraspinous musculature.
The main objective finding in neck-tongue syndrome is decreased sensation of the ipsilateral half of the tongue. Often associated with this finding are pseudoathetoid movements of the tongue resulting from an impairment of the proprioceptive fibers.
How is Neck Tongue Syndrome diagnosed?
Magnetic resonance imaging (MRI) of the brain and brainstem should be performed in all patients thought to have neck-tongue syndrome. MRI of the brain provides the best information regarding the cranial vault and its contents.
MRI is highly accurate and helps identify abnormalities that may put the patient at risk for neurological disasters secondary to intracranial and brainstem pathology, including tumors and demyelinating disease.
Magnetic resonance angiography (MRA) may be useful to help identify aneurysms responsible for the patient’s neurological symptoms. In patients who cannot undergo MRI, such as patients with pacemakers, computed tomography (CT) is a reasonable second choice.
Clinical laboratory tests consisting of a complete blood cell count, automated chemistry profile, and erythrocyte sedimentation rate are indicated to rule out infection, temporal arteritis, and malignancy that may mimic neck-tongue syndrome.
Endoscopy of the hypopharynx with special attention to the piriform sinuses also is indicated to rule out occult malignancy. Differential neural blockade of the C2 nerve may help strengthen the diagnosis of neck-tongue syndrome.
Neck-tongue syndrome is a clinical diagnosis that can be made on the basis of a targeted history and physical examination. Because of the rarity of this syndrome, the clinician must consider neck-tongue syndrome to be a diagnosis of exclusion. Diseases of the eyes, ears, nose, throat, and teeth may coexist and confuse the diagnosis.
Tumors of the hypopharynx, including the tonsillar fossa and piriform sinus, may mimic the pain of neck-tongue syndrome, as may tumors at the cerebellopontine angle. Occasionally, demyelinating disease may produce a clinical syndrome identical to neck-tongue syndrome. The jaw claudication associated with temporal arteritis also may confuse the clinical picture, as may glossopharyngeal neuralgia.
The initial treatment of neck-tongue syndrome should consist of immobilization of the cervical spine with a soft cervical collar. A trial of nonsteroidal antiinflammatory drugs (NSAIDs) or cyclooxygenase-2 (COX-2) inhibitors represents a reasonable next step. Case reports suggest that myofascial release, exercise, and spinal manipulative therapy may provide symptomatic relief.
Blockade of the atlantoaxial joint and C2 nerve root with a local anesthetic and steroid also should be considered. For refractory cases, cervical fusion of the upper cervical segments may be required.
Because of the rarity of neck-tongue syndrome, it is often misdiagnosed.
Further complicating the confusion surrounding the diagnosis of this painful condition is the fact that many of the pathological processes that mimic neck-tongue syndrome are also difficult to diagnose, especially diseases of the hypopharynx. For these reasons, the diagnosis of neck-tongue syndrome should be approached with extreme caution.
Neck tongue syndrome is a unique and uncommon cause of neck pain. The associated ipsilateral tongue numbness is pathognomonic for the syndrome and is unusual in character. An analogous type of proprioceptive numbness is seen in patients with Bell palsy.
Given the rarity of this painful condition, the clinician should search carefully for other causes of the symptoms before attributing them to neck-tongue syndrome.