People without a medical education are unlikely to imagine what the hyoid nerve is. But in some cases, this information can be very important. There are a number of problems that worsen a person’s quality of life related to the tongue and hyoid nerve. Let's consider them in more detail.
Just about complicated
The hyoid nerve innervates, that is, it connects the nerve endings of the tongue with the central nervous system. It provides motor (efferent) innervation, allowing the central nervous system to control the activity of the tongue and the circular muscles of the mouth. The nerve is a paired, it is the twelfth pair of cranial nerves. It leaves the anterolateral groove, and its core is located along the medulla oblongata.
The jaw-hyoid nerve sends impulses and provides activity of the upper, lower, longitudinal, transverse and vertical muscles of the tongue. He is responsible for the movement of the chin-lingual, sublingual-lingual and subulate muscles.
How to understand a doctor. Meaning of Terms
Since information about the hyoid nerve is a little difficult to perceive, patients do not always understand what the specialist is talking about. To understand the diagnosis, you need to know some terms:
- Hemiglossoplegia. This term refers to paralysis of half the tongue.
- Glossoplegia is a state of complete paralysis of the tongue.
- "Dysarthria." Diagnosis of impaired articulation of speech. Slurredness is accompanied by a sensation of an extraneous substance in the mouth.
- Anartria is a diagnosis that clarifies that articulate speech is not possible.
These terms are found in medical histories related to the hyoid nerve quite often. Their meaning is better to remember.
What the patient complains about
When contacting a doctor, patients mainly complain of weakness of the tongue. It is difficult for them to speak, and sometimes even to swallow. Gradually, the problem grows, and the language moves worse. It may seem to the patient that he has “a mouth full of porridge”, because of which it is difficult to make out his speech. In difficult cases, speech disappears completely.
Medical examination
If a specialist suspects that the hyoid nerve is affected, he will determine the symptoms when examining the tongue in the oral cavity. First of all, the doctor asks to stick out his tongue. Do not be surprised, this simple action may indicate the main problem. The doctor can visually determine the degree of the disease. If the hyoid nerve does not function well, then the tongue deviates to the side. This is due to muscle hypotension on the one hand. The entire surface of the organ looks wrinkled and becomes uneven. But here it must be borne in mind that many patients deliberately reject the tongue towards the doctor so that he can better examine it. If there is doubt about whether the tongue is arbitrarily or involuntarily rejected, then the patient is offered to touch the tip of his upper lip. If there is no pathology, then the tip will be located in the middle, if the nerve is affected, it will shift to the side.
In addition to deviations, the doctor should pay attention to atrophy and fibrillar twitching.
Bilateral lesion of the hyoid nerve is observed in approximately 20% of cases. This disease is less treatable and can lead to complete loss of speech.
Diagnosis options. Neuropathy
In fact, neuropathy is a nerve lesion that is non-inflammatory in nature. In the case of the hyoid nerve, this diagnosis is divided into central and peripheral neuropathy.
Central affects the corticonuclear pathway of the nerve. The problem affects the cortex and nucleus of the twelfth pair of cranial nerves. This type of neuropathy is usually combined with facial nerve problems. When protruding, the tongue deviates to the opposite side of the lesion, since the nucleus of the hyoid nerve has connections with the opposite hemisphere. Atrophy and fibrillar twitching are not observed.
A process can have several stages. If the hyoid nerve is affected only in the region of the internal division, then only the functions of the lingual muscles are affected.
If the lesion begins below the exit from the canal of the hyoid nerve, then the problem affects the nerve fibers connected to the cervical roots. This leads to impaired functioning of the muscles that hold the larynx. When swallowing, a shift to the healthy side will be observed.
Peripheral neuropathy
Peripheral sublingual nerve palsy is diagnosed if the process affects the intracerebral root or nucleus. Doctors may use the wording “paresis of the muscles of the tongue”. Both of these names are equivalent. Most often, this disease is one-sided, but if a pathology of the nuclei is observed, then muscle damage can occur on both sides. On examination, atrophy of the problem part of the tongue is noticeable. The fabric loses its elasticity, becomes flabby and “wrinkled”. If the case is severe, then the motor activity of the organ is significantly limited.
If the hyoid nerve is affected on one side, then in the oral cavity the tongue shifts to the healthy side. When the patient sticks out his tongue, he moves to the sore side. A doctor may observe fibrillar trembling (twitching). Sometimes this process is confused with the usual twitching of muscles, which can happen with tension of the tongue during protrusion. If the specialist noticed a similar phenomenon, then he should ask the patient to relax the muscles of the tongue. Normal muscle tremor will pass, and fibrillar will remain.
With deep nuclear damage to the nerve, an atrophy of the circular muscle of the mouth may be an additional symptom. The patient is not able to perform the simplest actions - to put his lips in a tight tube, whistle, blow.
With bilateral flaccid paresis, a paralyzed organ lies on the bottom of the oral cavity. Speech and swallowing are significantly impaired.
The causes of damage to the nucleus of the hyoid nerve are quite serious. Of the most common are:
- bulbar palsy;
- motor neuronal disease, that is, damage to motor neurons ;
- syringobulbia;
- polio;
- vascular problems.
We will explain in more detail the manifestations of several diseases.
Bulbar and pseudobulbar syndrome
The cause of the first disease is a degenerative degeneration of tissues in the cerebral cortex, impaired blood flow into the medulla oblongata, the appearance of stem tumors, polyencephalomyelitis, structural pathology, and trauma to the base of the skull.
Signs: immobility of the epiglottis, larynx and soft palate, voice change, loss of intelligible speech, difficulty in swallowing (liquid food can flow into the nose), respiratory failure. The vocal cords in the "cadaverous position", the tongue twitches fibrilally. If the facial and trigeminal nerve are additionally affected, the masticatory muscles atrophy, and the lower jaw sags.
Pseudobulbar syndrome is very similar to bulbar, but this is a defeat of the cortical-nuclear connections from two sides. Affected by a greater number of cranial nerves, including the hyoid nerve, cerebral ischemia occurs. Salivation, reflex movements of the eyeballs, bouts of crying or laughter, dementia and decreased intelligence are added to the symptoms.
Diagnostic methods and treatment
The doctor collects an anamnesis, performs a visual examination, prescribes a CT scan or MRI of the brain to confirm the diagnosis. This allows you to find out the cause of compression of the hyoid nerve.
Any treatment is prescribed after confirmation of the diagnosis. The main goal is a positive effect on the underlying disease. Self-medication is unacceptable!