The extrapyramidal system is a complex complex consisting of a number of closely interconnected gray matter nuclei. From a functional point of view, this complex represents the basis for the implementation of complex unconditioned reflexes (innate, species), called instincts (defensive, food, sexual, maternal and others).
The function of the extrapyramidal complex is also the regulation of muscle tone, normal friendly movements (synkinesis) and reflex motor reactions: friendly movements when walking, gesturing, withdrawing a hand from a hot object or when exposed to pain. Another function of this system is to provide postural reflexes (postures, position in space). Treatment for extrapyramidal disorders usually lasts a lifetime.
Extrapyramidal system
The main formations that make up the extrapyramidal system:
- lenticular nucleus;
- caudate nucleus;
- red core;
- substantia nigra;
- subthalamic nucleus;
- reticular formation;
- cerebellar nuclei;
- premotor cortex (this zone is directly related to both the extrapyramidal system and the pyramidal system).
These anatomical formations have close connections with each other and with other formations of the central nervous system.
It is the disturbances in the functioning of the cells that make up the formation of the extrapyramidal system, as well as their pathways, that cause the occurrence of extrapyramidal disorders. This group of diseases is characterized by a variety of symptoms.
What are the types of extrapyramidal disorders?
The modern classification of extrapyramidal disorders divides them into two large groups:
- 1. hypokinetic (parkinsonism, isolated akinesia);
- 2. hyperkinetic.
Hyperkinetic disorders, by their nature of occurrence, can be:
- spontaneous (chorea, ballism, types of myoclonus);
- actional or kinesiogenic, which are provoked by voluntary movements (some types of paroxysmal dyskinesias, kinetic tremor, dystonia);
- specific kinesiogenic - hyperkinesis that occurs only when performing certain movements (for example, spasm when writing or playing a musical instrument);
- reflex - caused by external irritations (for example, reflex myoclonus).
Based on the motor pattern, hyperkinetic disorders are classified as follows:
- rhythmic - caused by periodic contraction of agonist and antagonist muscles (tremor, myorhythmia);
- predominantly tonic - provoked by simultaneous contraction of agonist and antagonist muscles (dystonia);
- predominantly clonic (fast, mobile, phasic), manifested both in the form of simple movements caused by contraction of one muscle, and in the form of complex movements similar to a normal motor act (tics, chorea).
According to their prevalence, hyperkinesis is divided into generalized, segmental, focal and multifocal.
Selected extrapyramidal disorders
The clinical picture and variants of the course of disorders of the extrapyramidal system depend on the zone and mechanism of the lesion.
Parkinson's disease
This pathology is usually classified as a group of degenerative diseases of the central nervous system. The pathogenetic factor of the pathology is the death of neurons in a number of formations of the extrapyramidal system:
- substantia nigra;
- globus pallidus;
- shells.
The etiology of these disorders has not been established today, but there is evidence of a genetic predisposition.
It is necessary to distinguish:
- Parkinson's disease (primary form): in the structure of all cases of parkinsonism, this condition makes up the majority of cases (80%). The occurrence of pathology is due to genetic factors.
- Secondary parkinsonism, or Parkinson's syndrome. It is one of the symptoms of various lesions or diseases of the central nervous system.
Clinical picture
There is a gradual slowdown and the appearance of stiffness in active movements: it is noted that the changes first become noticeable in the right hand of right-handed people, since the disorders cause varying degrees of pronounced difficulties in writing and performing small actions with the fingers. Then, as the tremors and stiffness progress, changes become noticeable in other parts of the body:
- Hypertonicity of the skeletal muscles appears, due to which a certain posture is gradually formed, characterized by stooping and flexion of the limbs.
- Characteristic changes in gait are observed: it becomes “shuffling”, “mincing”. Propulsion appears: such a patient, as a rule, finds it difficult to step when starting to walk, and then, as a result of the center of gravity shifting forward, he cannot stop. Because of this, the patient loses his balance. Individual gait features are gradually erased.
- The chin and limbs begin to tremble. This is especially noticeable at rest.
- There is stiffening, poor facial expressions, and rare blinking of the eyelids - the so-called mask-like face.
- The clarity and intelligibility of speech decreases.
- Hypersalivation is possible.
- The pace of thinking slows down to varying degrees.
- There is a decrease in attention while intellectual abilities and memory are preserved in the first stages of the disease.
- From behavioral changes: in about half of the patients, motivation disappears, the range of interests narrows, the affective background decreases, even to chronic depression.
- Autonomic disorders will be expressed in urination disorders, constipation, impotence, decreased sense of smell, overproduction of sebum, leading to greasiness of the skin and hair.
Diseases causing secondary parkinsonism
The causes of this disorder can be the following actions and pathologies:
- Atherosclerosis of cerebral vessels.
- The patient's use of certain medications (for example, some antipsychotics).
- Intoxication, in particular, with ethyl alcohol, carbon monoxide, cyanide compounds, manganese.
- Addiction.
- Other degenerative diseases of the central nervous system - they can affect the extrapyramidal sphere and thus cause parkinsonism.
- Inflammatory processes affecting the central nervous system (encephalitis).
- Oncological damage to the brain.
- Some hereditary diseases.
- Traumatic brain injuries, including repeated head injuries (even not very severe ones).
To determine the form of the disease (primary or secondary), you should identify a history of conditions that contribute to the occurrence of parkinsonism:
- severe atherosclerosis;
- hypertonic disease;
- consumption of toxic substances that can provoke this pathology;
- neuroinfections or traumatic brain injury suffered by the patient.
Treatment
It is advisable to start using antiparkinsonian medications when motor restrictions have already appeared. The following groups of drugs are used for treatment:
- levodopa;
- amantadine;
- monoamine oxidase inhibitors;
- dopamine synergists;
- anticholinergics (Cyclodol).
To achieve a stable result, the dosage of medications must be constantly increased. It should be remembered that this feature will lead to the inevitable development of adverse reactions. To mitigate this undesirable phenomenon, treatment should begin with mild, low-dose medications, and the dosage should be increased only if absolutely necessary. A good result is obtained by combining drugs with different mechanisms of action.
Symptomatic therapy: autonomic disorders are eliminated with the help of drugs effective for constipation; Antidepressants relieve depression, anxiety and dyssomnia. Folk remedies that affect these same symptoms go well with drug treatment.
Essential tremor (benign, familial tremor)
This is a postural tremor that occurs in otherwise healthy people, often in several members of the same family. The anomaly has an autosomal dominant mechanism of inheritance. The pathogenesis and its occurrence have not been established to date.
The disease often debuts in elderly and middle-aged people.
The tremor is typically localized in one or both arms and head. Hyperkinetic disorder does not extend to the lower extremities. Some patients experience trembling of the voice.
Over time, tremor may progress, but does not lead to disability, except in cases where a person’s work involves writing or other movements that involve fine motor skills of the hands.
When taking small doses of alcohol, the tremor decreases somewhat.
Treatment
If the tremor is mild, no treatment is required.
Progressive supranuclear palsy (Steele-Richardson-Olszewski syndrome)
This is a rare disease of a degenerative nature, which is sporadic.
The basis of pathogenesis is the degeneration and death of neurons in the midbrain, pons, basal ganglia and dentate nucleus of the cerebellum. A decrease in the content of dopamine and gamma-linolenic acid in the caudate nucleus and putamen is also characteristic.
The disease debuts between the ages of 45 and 75 years. Men get sick more often (occurs 2 times more often than in women).
A characteristic feature is supranuclear ophthalmoplegia. This is where the disease begins, and later horizontal gaze paresis occurs.
Late stages are characterized by impairment of smooth pursuit eye movements.
Muscle dystonia, mainly of the neck extensors, rigidity of the muscles of the limbs and hypokinesia are often associated. After the manifestation of such abnormalities, a differential diagnosis of Parkinson's disease and symptomatic parkinsonism is necessary.
Specific features that distinguish progressive supranuclear palsy from Parkinson's disease are:
- pronounced paresis of downward gaze;
- horizontal gaze paresis;
- predominance of torso extensor tone;
- absence of tremor.
If pharmacotherapy is started, antiparkinsonian drugs will be ineffective for this disease.
The combination of ophthalmoplegia with rigidity of the neck and trunk muscles provokes frequent falls.
In some cases, a disorder of the facial nerve, dysarthria, and dysphagia are associated. Advanced stages are characterized by manifestations of pseudobulbar palsy:
- increased gag reflex;
- increased mandibular reflex;
- the appearance of violent laughter and crying;
- strengthening of tendon reflexes;
- pathological extensor reflexes.
A decrease in intelligence is often observed.
No focal dysfunctions of the cortex are recorded.
Progressive supranuclear palsy can be suspected when a middle-aged or elderly person complains of frequent falls, and upon examination extrapyramidal disorders, neck extensor dystonia, or downward gaze paresis are recorded.
Treatment
As a rule, drug treatment is ineffective. The life expectancy of patients after the onset of the disease rarely exceeds 10 years. Rigidity and hypokinesia can be reduced with the help of dopaminergic drugs. M-anticholinergics and antidepressants help improve speech, gait and eliminate violent laughter and crying. But the disease continues to progress. Over time, aspiration of food occurs and exhaustion develops.
Corticobasal degeneration
This rare disease is sporadic.
The onset of pathology occurs in old age and is manifested by damage to one or more limbs.
The main pathogenetic link is the death of neurons and gliosis of the cerebral cortex and substantia nigra.
Neurological examination reveals symptoms of parkinsonism. But the diagnosis of Parkinson's syndrome does not explain all clinical manifestations.
The phenomena of apraxia come to the fore. Later, other disorders of cortical functions appear:
- aphasia;
- agnosia;
- sensory inattention;
- mild dementia.
The differential diagnostic feature is the ineffectiveness of antiparkinsonian drugs.
The disease continuously progresses, leading to disability and death.
Striatonigral degeneration
The name of the disease indicates the most affected structures - the substantia nigra, subthalamic and caudate nuclei, putamen, and globus pallidus.
The age group for which this disease is typical is from 60 years. It occurs with equal frequency in men and women.
Parkinsonism syndrome is characteristic, but tremor is less pronounced. The intellectual sphere is not affected.
Autonomic disorders occur, and then a neurological examination reveals, in addition to extrapyramidal disorders, pyramidal disorders and deviations from the cerebellum.
Treatment for striatonigral degeneration is not selling well. Antiparkinsonian drugs are ineffective.
Torsion dystonia
This term is commonly used to describe dystonia that is not accompanied by other neurological disorders in the absence of birth trauma.
The pathogenesis of this disorder and the biochemical disorders leading to its development have not been sufficiently studied.
The diagnosis is made by sequential exclusion of other causes.
Among all cases of torsion dystonia, both sporadic and hereditary forms of the disease have been recorded. The following transmission routes are typical for hereditary ones:
- autosomal dominant;
- autosomal recessive or recessive;
- linked to the x chromosome.
Beginning in childhood, the disease primarily affects the muscles of the legs. This early form has a less favorable prognosis compared to late-onset dystonia.
In approximately 30% of cases, patients lose the ability to walk as a result of pathology.
Signs of pathology
The clinical picture is characterized by violent movements and unusual postures. Starting from the legs, the disease spreads to the muscles of the neck, torso, limbs and face. At first, violent movements occur when voluntary movements are attempted. As the disease progresses, they become permanent and lead to disability.
A special case of torsion dystonia is Segawa's disease (DOPA-sensitive dystonia), which is inherited in an autosomal dominant manner. Begins in childhood. Muscular dystonia in this pathology is combined with hypokinesia and rigidity.
Treatment
Treatment is symptomatic, but effectiveness is often low.
M-anticholinergic drugs are most effective in high dosages. Treatment is started with low doses, which are gradually increased until results are obtained or side effects develop.
In some cases, Haloperidol and phenothiazines help, but they are characterized by side effects such as parkinsonism.
Sometimes symptoms can be reduced with Diazepam, Baclofen, Carbamazepine.
For unilateral lesions, thalamotomy is indicated.
In Segawa's disease, levodopa in low doses has shown high effectiveness.
Segmental dystonia
The difference between this disease and torsion dystonia is that violent movements as a result of impaired muscle tone are recorded only in certain muscle groups and areas of the body.
There is a hypothesis that this pathology is a type of torsion dystonia.
Blepharospasm, oromandibular dystonia, and spinocerebellar degeneration can occur in isolation.
Blepharospasm is an uncontrollable spasm of the muscles around the eyes.
Oromandibular dystonia is manifested by involuntary contractions of the muscles of the masticatory group, tongue and facial muscles located around the mouth. Externally, it is expressed by stretching, wrinkling of lips, clenching of jaws, movements and protruding of the tongue. In combination with blepharospasm, the anomaly is called Meij's facial spasm.
Spasmodic torticollis is a special case of segmental dystonia and is characterized by violent movements of the head to the side. Such hyperkinesis can be combined with tilting the head forward or backward.
At the beginning of the disease, the pathological tone is transient, but as it progresses, the disorder becomes permanent, as a result of which the person’s head is always in an unnatural position. In the first months, spontaneous remissions are characteristic, but this does not affect the progression of the pathology.
Treatment
Pharmacotherapy is ineffective in most cases.
Sometimes symptoms regress somewhat under the influence of Diazepam, Baclofen, Carbamazepine.
Injections of botulinum toxin type A are used into muscles with impaired tone. This substance has the property of temporarily blocking the release of acetylcholine from the presynaptic membrane. The duration of the effect is from several weeks to several months. Injections of the drug can be repeated. Today, this is the most effective method of treating most types of segmental dystonia.
Spinocerebellar degeneration
This disease is transmitted by an autosomal dominant mechanism and debuts in the third or fourth decade of life.
The pathology is most typical for residents of Portugal.
The clinical picture is characterized by moderately severe symptoms of parkinsonism. Spasticity, decreased reflexes, cerebellar disorders, and external ophthalmoplegia predominate. Sometimes neuropathy is associated.
The intellectual sphere does not suffer. Structural abnormalities in the brain correspond to pathological abnormalities in strionigral degeneration. But the damage to the corpus nigra, globus pallidus, putamen, caudate and subthalamic nuclei is accompanied by changes in the dentate nucleus of the cerebellum.
Treatment for the disease has not been developed.
Professional spasm
This is a dystonic disorder that develops on the basis of professional skills and movements that require a high degree of precision:
- writer's cramp;
- barber spasm;
- telegraph operators;
- violinist;
Clinical manifestations using the example of writer's cramp: forced contraction of the muscles of the hand and forearm when writing.
As the pathology progresses, muscle dystonia also appears during other activities - shaving, applying cosmetics, cooking, using cutlery.
Drug therapy has very low effectiveness and patients in most cases have to learn to use their other hand.
The pathogenesis of the disease is under study. There is evidence that the occurrence of deviation is due to a violation of the processing of efferent signals from the affected limb.
Drug-induced extrapyramidal disorders
Drug-induced extrapyramidal disorders occur as a result of side effects of certain medications:
Name of disorder | Characteristic | Tactics |
Drug-induced parkinsonism | Development mechanisms:
Peculiarities:
Differential diagnosis is based on medical history | Cancel antipsychotic drugs and replace them with drugs that have a more pronounced m-anticholinergic effect, or prescribe m-anticholinergic blockers. Taking levodopa is ineffective and can cause mental disorders |
Acute drug-induced hyperkinesis | Acute dystonia, manifested by blepharospasm, spasmodic torticollis and other hyperkinesis in the form of chorea or spasms of the facial muscles. Develops as a result of long-term treatment with dopamine receptor blockers. Symptoms develop during the first week of the treatment course, usually within 1-48 hours. More typical for young people | The use of m-anticholinergic drugs (benzatropine, diphenhydramine) is effective. |
Late neuroleptic akathisia | Akathisia is motor restlessness. Such a patient experiences a constant need to move. The development of this effect is most typical for long-term use of antipsychotics. Disorders are more common in women | Discontinuation of the drug that provoked the pathology, with replacement with drugs that have a more pronounced m-anticholinergic effect |
Late neuroleptic hyperkinesis | They develop as a result of prolonged use of antipsychotics that block dopamine receptors. The likelihood of developing this disorder increases with age. Pathogenesis unknown. There is a hypothesis that this pathology is caused by an increase in the sensitivity of dopamine receptors under the influence of neuroleptics. But it develops only in some patients. The appearance of hyperkinesis is typical no earlier than six months after the start of therapy. The disorder manifests itself in the form of choreoathetoid movements of the muscles of the face and mouth in adults and limbs in children. Generalized deviation is rare, mainly in elderly patients. Tics may appear. Differential diagnosis - based on medical history | At a young age and in children, disorders often resolve on their own. In elderly patients, they persist for a long period. This deviation is difficult to treat. Stopping the antipsychotic may help. M-anticholinergic drugs are effective |
Neuroleptic malignant syndrome | Manifestations:
Mortality 5-20%. The disorder develops in 2-3% of patients undergoing treatment with antipsychotics. The development of neuroleptic malignant syndrome is more typical for young people. Deviations can develop at any time, but more often - in the first month of treatment. Usually symptoms increase within 1-2 days. Pathology should be differentiated with the following conditions:
This pathology is distinguished from drug-induced parkinsonism by the presence of autonomic disorders and hyperthermia. Possible complications:
|
Recovery takes 2-3 weeks. Abrupt withdrawal of antipsychotic drugs causes the development of withdrawal syndrome. Therefore, the patient must be under constant supervision |
Other movement disorders |
| Dose adjustment downward or discontinuation of the offending drug |
Gilles de la Tourette syndrome
This is a disease of currently unknown etiology. The connection between its origin and ethnic or social factors and perinatal pathology has not been established.
The disease debuts between the ages of 5 and 15 years and occurs with alternating exacerbations and remissions.
Familial cases are known. The type of inheritance is autosomal dominant. Boys get sick more often. The pathogenesis is unclear, morphological changes have not been established.
Since the symptoms of the disease are known to be abolished by dopamine receptor blockers, it is believed that it is caused by excessive activity of the dopaminergic system.
Clinical picture
A characteristic manifestation of the pathology is multiple chronic motor and vocal tics. More often the disease begins with movement disorders. Tics most often involve the facial muscles and are manifested by blinking, grunting, raising the eyebrows, closing the eyes, pursing the lips, or twitching the facial muscles. Later, other motor tics join in, then vocal tics appear, manifesting themselves in the form of mooing, whistling, grunting, sighing, coughing, and grunting. And in a number of cases, involuntary shouting of words, including swear words, and involuntary repetition of heard phrases were noted.
The localization and nature of tics are not constant and may change. For some time they can be suppressed by an effort of will. In some cases, complex tics occur: jumping or repeated self-mutilation (biting nails, lips, pulling hair).
There are sensory tics in the form of repeated sensations: tickling, cold, heat, feeling of pressure.
Tics are often accompanied by behavioral deviations: neuroses, obsessive states, attention deficit disorder and hyperactivity.
Among patients, left-handers and ambidextrous people are more common. An electroencephalogram reveals nonspecific changes.
Often the diagnosis is made years after the onset of the disease.
Numerous tics can lead to social maladjustment, causing depression, and in severe cases, suicidal intentions.
Differential diagnosis
Differential diagnosis should be carried out with numerous different tics characteristic of childhood, which have a good prognosis and do not require therapy. Tics in childhood and adolescence often stop on their own.
Such hyperkinesis is characteristic of Wilson's disease.
Huntington's syndrome is distinguished by the presence of dementia and features of hyperkinetic disorders. The final diagnosis is made using gene diagnostics.
If the history does not indicate rheumatic attacks, polyarthritis and heart damage, then Sydenham's chorea can be mistaken for Gilles De La Tourette syndrome. But with this disease, hyperkinesis disappears after 3-6 months.
Multiple tics should be differentiated from the consequences of encephalitis and taking psychostimulants and antipsychotics.
Treatment
Treatment is long-term, symptomatic.
Clonidine is effective in half of patients. When prescribing, one should take into account its side effects: drowsiness, drooling, dry mouth.
Haloperidol is considered a proven and effective remedy. Treatment begins with a low dose, which is gradually increased until the effect or side effects appear.
Carbamazepine or Clonazepam are effective.
Family counseling and psychotherapy are indicated.
Restless legs syndrome
This is a common chronic disease, often familial, with an autosomal dominant inheritance mechanism. This pathology is characterized by a constant need to move the legs due to difficult-to-describe unpleasant sensations in the deep tissues of the lower extremities.
Sometimes the sensations spread to the hands.
Usually the disorder manifests itself at rest, so it can disrupt sleep. Movements can continue even during sleep (recorded by sonography).
The etiology has not been established.
Restless legs syndrome often occurs during pregnancy, with uremic or diabetic neuropathy, primary amyloidosis and malignant neoplasms.
Physical examination reveals underlying disease or mild neuropathy, but in most cases no abnormalities are found.
In the case of a combination of restless leg syndrome and iron deficiency anemia, treatment of anemia often leads to recovery.
Dopaminergic drugs (levodopa, bromocriptine), benzodiazepines (Diazepam, Clonazepam), and narcotic analgesics (Codeine, Oxycodone) are effective.
The extrapyramidal system is a deep and ancient system for regulating movements at an unconscious level. For our distant ancestors - fish, amphibians, it is the main and only one. In mammals and humans its meaning has changed. It regulates muscle tone, unconscious motor responses, maintaining balance, and is involved in the automation of stereotypical movements. Quite often, neurologists notice such phenomena and symptoms that indicate the occurrence of extrapyramidal diseases. What are the symptoms of damage to the extrapyramidal system? This is what we will talk about.
It is impossible to embrace the immensity
Symptoms and treatment of extrapyramidal disorders is a whole section of neurology, and there is even a specialization in this area, just as there are separate outpatient and even inpatient centers where diseases of the extrapyramidal nervous system are diagnosed and treated. Therefore, we will limit ourselves to describing only the main signs that characterize extrapyramidal disorders. This “mosaic” approach is quite enough to awaken interest in the topic, and even teach the basics of “visual diagnostics”. Now, if you see a “strange” person on the street, you may tell your companions what is happening to him.
Syndromology
In total, there are several dozen different diseases of the nervous system associated with the “subcortex”, and if we add to this the variants of their course, we get an impressive list. But all this variety of “patterns,” as in a kaleidoscope, can be composed of small individual extrapyramidal actions that have been disrupted. This is how extrapyramidal symptoms developed. They refer to such general disorders as impaired muscle tone and movement.
Violations of tone
Changes in muscle tone, manifested by either diffuse or limited muscle hypotonia (this is quite rare), or its significant increase (they say, rigid muscles) is the first and important symptom.
Hypotonia is defined as lethargy and complete compliance, the amplitude in large joints is excessively large. As you know, normal, physiological tone still exhibits some resistance when trying to bend and straighten even a completely relaxed arm. It feels like you are bending and unbending the arm of a living person. In the case of muscle hypotonia, extrapyramidal disorders are manifested by the “doll hands” symptom. You can't help but feel like you're moving a dangling puppet hand.
Extrapyramidal rigidity is a diffuse increase in tone or muscle hypertension. In this case, the resistance of the arm or leg, which cannot relax, is constant from the very beginning of the movement to the end. Extrapyramidal symptoms in this case resemble “scalloping”. The muscles have forgotten how to work smoothly and move in tiny “jerks,” which resembles the intermittent movement of a gear wheel. If the “tooth” has a very small “step”, then we can talk about waxy flexibility. In any case, the resistance exerted by the patient's muscle is significant and constant. This lesion is characteristic of Parkinson's disease, which directly embodies many extrapyramidal disorders.
Movements
But muscle tone can be pathologically altered both during movement and at rest. It is not an indicator of a disorder of automatic movements, but only a violation of preparation for them. Therefore, there are also unconscious changes in motor activity, namely hypokinesia (depletion of movements), and hyperkinesis, which are manifested by a wide variety of movements.
A special, mixed variant of movement disorder with increased tone is tremor, or regular trembling, which occurs in a single rhythm. Tremor, like other dyskinesias, disappears during sleep, both in adults and children, and appears upon awakening. Tremor may be present in various diseases, such as parkinsonism, or may be the only symptom. In some cases, the presence of tremor makes it possible to diagnose endocrine pathology (it can occur, for example, with thyrotoxicosis).
With subcortical syndromes, a “commonwealth” of the effects of dystonia (impaired tone) with dyskinesia (movement disorders) often occurs. Rigidity is often combined with hypokinesia (bradykinesia, oligokinesia), for example, in Parkinson's disease. Conversely, muscle hypotonia is associated with hyperkinesis, for example, chorea. The latter combination occurs when the neostriatum is damaged, and rigidity and hyperkinesis manifests itself when the substantia nigra is damaged. It is this phenomenon that we will talk about in more detail.
Parkinsonism
At first glance, if the extrapyramidal nervous system “manages” unconscious movements, then extrapyramidal disorders should be expressed in motor disorders. When the pyramidal tracts are damaged, paralysis occurs. If it is complete and no movements are possible, it is called plegia, and if the function is partially preserved, neurologists call it paresis. What does “unconscious paralysis” look like? At first glance, this phenomenon is simply impossible to imagine. But it turns out that there is such an extrapyramidal pathology as “shaking paralysis”, or Parkinson’s disease. Probably everyone has heard this neurological diagnosis.
Parkinsonism occurs when neurons in the substantia nigra lose the pigment melanin.. As a result, their degeneration occurs and the loss of dopamine begins. The same process occurs in the striatum. Most often, EPS (extrapyramidal symptoms) appears symmetrically and for an unknown reason. This is Parkinson's disease. But sometimes extrapyramidal insufficiency occurs on one side. This happens when, for example, there is a reason: hemorrhage or thrombosis of the corresponding vessels (stroke). As a result, secondary parkinsonism develops, and on the opposite side of the body.
Unfortunately, every third case of parkinsonism is drug-induced and is associated with the abuse of antipsychotic drugs, due to the development of neuroleptic syndrome. This often occurs in drug addicts and substance abusers who use chlorpromazine, haloperidol and other drugs without knowing the consequences.
Clinic
Probably, those people who want to understand what extrapyramidal movement disorders are should show a patient with Parkinson's disease. Of course, he will not dance and jump, as with chorea, his face will not distort with violent laughter, and his fingers will not make bizarre and worm-like movements, as with athetosis. But, based on the totality of clinical signs, it is parkinsonism that students study first. Judge for yourself. The characteristic clinical and neurological signs of parkinsonism are:
- akinesia (impoverishment of all conscious movements, complete absence of gestures);
- propulsion, retropulsion, lateropulsion. The patient begins to move with great difficulty, and once he starts, he cannot finish it. His last steps are respectively directed forward, backward or sideways;
- amimia, hypomimia (mask-like face), on which moving eyes simply “live.” A patient with parkinsonism does not lose the mobility of the extraocular muscles, and the “serration” phenomenon does not occur in them. Therefore, it is easier for such a patient to communicate with his eyes, for example, by pointing to an object, instead of saying words or starting such a painful movement;
- dysarthric and monotonous speech. The speech component is added because rigidity of the tongue and vocal muscles occurs;
- tremor appears, similar to “counting coins”, mainly in the hands, thumbs and index fingers.
Perhaps one of the most striking manifestations of parkinsonism is the “falling head” test. If a patient lying on his back raises his head and sharply removes his hands, then any normal person’s head will hit the couch. Parkinson's does not have this reaction. Due to “toothed” hypertonicity, the head slowly, with barely noticeable jerks, falls onto the couch.
In addition to parkinsonism, which is a classic example of rigidity and hypertension, let's consider its alternative - extrapyramidal hypotonicity syndrome - hyperkinesia.
Hyperkinesis, or damage to the neostriatum
We present the second, large group of subcortical or subcortical disorders, which are based on excessive motor activity. In addition to damage to the striatum, damage to the most ancient structure, the globus pallidus, is also possible. The result is pallidal syndrome, which is sometimes called striopallidal syndrome.
Morphologically, these diseases represent situations in which the influence of the striatum on “subordinate structures” is sharply weakened, and a wide variety of circulation of motor impulses occurs until spontaneous attenuation of the signal occurs. The main representatives of diseases of this group are:
- Athetosis.
This disease occurs when a network of small neurons in the striatum dies and is replaced by glial scars. As a result, the patient experiences bizarre, worm-like and extremely elaborate movements. There is a tendency to hyperextend and “wring” the fingers. In addition, grimaces of the tongue and facial muscles occur, laughter or crying may appear;
- Torsion spasm or torsion dystonia.
This is nothing more than athetosis of the trunk muscles. The movements are no less bizarre and resemble wriggling ones. Figuratively speaking, this is “a corkscrew entering a bottle.” As a result, such patients have very difficult gait. Dystonic motor activity is nothing more than rhythmic spasms of agonist-antagonist muscles.
Here we should make a digression, after which the very physical basis of all violent movements can become clear. Normally, after contraction, the muscle simply relaxes and goes into a resting state. But in this case, the inhibitory influences are blocked. The muscle cannot simply relax. And, in order to somehow replace complete relaxation, there is an alternating contraction of the agonist-antagonist muscles, “pulling” in opposite directions.
The second variant of hyperkinesis, which affects the putamen and the central medial thalamic nucleus, is spastic torticollis. The sternocleidomastoid and trapezius muscles are often affected. The result is movements, involuntary and slow, that pull and turn the head to the side and down. Often it needs to be supported by hand.
- Chorea.
This is an interesting subcortical syndrome, which manifests itself with fast, completely chaotic movements in the muscles, which are very reminiscent of voluntary ones. It is even difficult for a simple person to understand that he is not being played and is not being “made a fool” in front of him. With chorea, a dancing, bouncing gait and grimacing occurs. What matters most is
Local subcortical vestibular syndrome described by N.S. Blagoveshchenskaya, V.K. Egorova, 1976. It was observed by the authors in intracerebral neuroectodermal tumors of the cerebral hemispheres with a location in the parietotemporal, parietotemporal-occipital, frontotemporal and frontoparietal regions. The syndrome is characterized by a clear predominance of experimental nystagmus, often towards the focus, inhibition and dissociation of experimental nystagmus. Due to the effect of the tumor on the subcortical diencephalic structures, pronounced autonomic, sensory and motor reactions are observed during vestibular tests. The listed symptoms precede the appearance of cerebral symptoms or are detected when they are of low severity.
With damage to the frontal lobe there is weakening of optical-kinetic nystagmus in the direction opposite to the lesion, which is associated with damage to the cortical gaze center (field 8).
When the focus is located in deep parts of the temporal lobe there is a weakening or loss of optikokinetic nystagmus on the side contralateral to the lesion, which is usually combined with hemianopsia.
For deep tumors of the parietotemporal and parieto-temporo-occipital localization there is a loss or sharp weakening of the optikokinetic nystagmus in the direction opposite to the focus. This is due to damage to the optomotor pathways in the deep paraventricular regions of the cerebral hemispheres. This tumor localization is often complicated by dislocation syndromes, which leads to the complication of vestibular disorders due to the addition of stem vestibular disorders. When determining the topical diagnosis of a lesion of the vestibular tract, it is necessary to take into account that vestibular disorders can be caused by processes in the periphery.
Yes, myofascial trigger points located in the clavicular region of the sternocleidomastoid muscles (muscles) can cause a disorder of vestibular function and a violation of spatial perception with impaired balance and orientation of the body in space, postural dizziness. Some patients are unable to appreciate spatial relationships and, when trying to pass through a door, stumble upon the door frame on the side where the most active trigger points are located.
Description:
Neuroleptic extrapyramidal disorders are a complex of neurological complications manifested by motor disorders associated with the use of neuroleptic drugs (antipsychotics). Neuroleptics can cause almost the entire spectrum of extrapyramidal disorders: dystonia, chorea, akathisia, stereotypies. According to the American DSM-IV classification, extrapyramidal movement disorders associated with taking antipsychotics can be divided into parkinsonism, acute dystonia, acute akathisia and tardive dyskinesia.
Symptoms:
Features of neuroleptic parkinsonism that distinguish it from parkinsonism of other etiologies are subacute development, symmetry of manifestations, combination with drug-induced dyskinesias (dystonia or akathisia), endocrine disorders (increased prolactin), non-progressive course, insignificant (in most cases) severity of postural instability and the absence of severe postural disorders. Symptoms include bradykinesia (slow pace of movements, difficulty in initial movements, difficulty turning), rigidity (stiffness, muscle tension), cogwheel sign (intermittent, stepped movements), tremors of the extremities, mask-like face, drooling. If these symptoms reach a severe degree, akinesia may develop, indistinguishable from. In severe cases, it can also develop.
A typical resting tremor (“rolling of pills”) is rarely observed in neuroleptic parkinsonism, but a rough generalized tremor is common, detectable both at rest and during movement. Sometimes tremor occurs that involves only the perioral region (“rabbit syndrome”).
Parkinsonism syndrome, as a rule, is reflected in the mental sphere: the so-called phenomena are characteristic. mental parkinsonism, or “zombie syndrome,” which includes emotional (emotional indifference, anhedonia, lack of pleasure from activities), cognitive (slow thinking, difficulty concentrating, feeling “empty in the head”) and social (loss of initiative, decreased energy , loss of social connections) parkinsonism. In some cases, secondary negative symptoms (abulia, anhedonia, flattening of affect, emotional isolation, poor speech), which is a side effect of psychopharmacotherapy, are difficult to distinguish from primary negative symptoms characteristic of schizophrenia spectrum disorders; Moreover, the psychoemotional manifestations of drug-induced parkinsonism are not always accompanied by noticeable neurological disorders.
The clinical picture of acute dystonia is characterized by a sudden onset with the development of dystonic spasms of the muscles of the head and neck. Suddenly, either forced opening of the mouth, protruding tongue, violent grimaces, with turning or throwing the head back, occur. May also occur. A number of patients experience oculogyric crises, which are manifested by forced abduction of the eyeballs, lasting from several minutes to several hours. Some patients experience either widening of the palpebral fissures (the “bulging eyes” phenomenon). When the trunk muscles are involved, opisthotonus, lumbar hyperlordosis, and scoliosis can develop. In some cases, the “Leaning Tower of Pisa” syndrome is observed, characterized by tonic lateroflexion of the trunk. The limbs are rarely involved.
Motor disturbances can be local and occur in typical areas, affecting an isolated muscle group, or generalized, accompanied by general motor excitation with affects of fear, narrowing of consciousness and autonomic disorders (profuse sweat, vasomotor reactions, etc.).
Dystonic spasms look repulsive and are extremely difficult to tolerate. Some of them (such as laryngospasm - dystonia of the laryngeal muscles) are life-threatening. Muscle spasms are sometimes so severe that they can cause joint pain.
is subjectively experienced as an intense unpleasant feeling of restlessness, the need to move, which is especially pronounced in the lower extremities. Patients become fidgety, stomp from foot to foot, have to constantly walk to relieve anxiety, and are unable to sit or stand still for several minutes.
The clinical picture of akathisia includes sensory and motor components. The sensory component includes unpleasant internal sensations - patients are aware that these sensations encourage them to move continuously, but they often find it difficult to give specific descriptions of them. These sensations can be general (anxiety, internal tension, irritability) or somatic (heaviness or dysesthesia in the legs). The motor component of akathisia is represented by movements of a stereotypical nature: patients can, for example, fidget in a chair, constantly change position, rock their torso, cross their legs, swing and tap their legs, tap their fingers, finger them, scratch their head, stroke their face, unbutton and fasten buttons. While standing, patients often shift from foot to foot or march in place.
Akathisia is often the main reason for patient non-compliance with drug therapy and refusal of therapy. Constant discomfort can increase the patient's sense of hopelessness and is one of the reasons for the appearance of suicidal thoughts. Even mild akathisia is extremely unpleasant for the patient, often causes refusal of treatment, and in advanced cases can be a cause. There is evidence that akathisia can lead to a worsening of the patient's pre-existing psychopathological symptoms, leading to suicide and acts of violence.
The presence and severity of akathisia can be objectively measured using the Burns Akathisia Scale.
Causes:
The term “drug-induced extrapyramidal disorders” also includes disorders caused by the use of other drugs that alter dopaminergic activity: for example, antidepressants, calcium antagonists, antiarrhythmic drugs, cholinomimetics, lithium, antiparkinsonian drugs, anticonvulsants.
Treatment:
For treatment the following is prescribed:
Treatment of neuroleptic parkinsonism includes the need to discontinue the drug that caused the development of parkinsonism, reduce the dose or replace it with a milder antipsychotic that is less likely to cause extrapyramidal disorders. In parallel, an antiparkinsonian drug from the group of anticholinergics is prescribed for a period of at least 2-3 months: trihexyphenidyl (Parcopan, Cyclodol), or biperiden (Akineton), or benztropine (Cogentin); other authors consider it desirable to prescribe amantadine, which is no less effective and less likely to cause severe side effects. Over the course of several months, a significant proportion of patients develop tolerance to the extrapyramidal effects of the antipsychotic, so gradual withdrawal of the antiparkinsonian drug may be attempted; If, after discontinuation of the drug, symptoms of parkinsonism reappear, you should continue taking it for a long time. Some sources also mention the desirability of prescribing vitamin B6.
When the antipsychotic is discontinued or its dose is reduced, the manifestations of parkinsonism usually regress within a few weeks, but some patients experience a slower decrease in motor disorders or their stationary course. Some Russian authors, in case of protracted extrapyramidal symptoms in patients with residual cerebral organic insufficiency (“protracted extrapyramidal syndrome” according to I. Ya. Gurovich), recommend prescribing high doses of antiparkinsonian correctors in combination with nootropics, while simultaneously reducing the dose of antipsychotics taken or prescribing drugs with minimal extrapyramidal activity; It is also recommended to carry out extracorporeal detoxification methods - and.
Western authors recommend the use of anticholinergic drugs for acute dystonia, such as benztropine (analogues on the Russian market - cyclodol and akineton), intravenous or intramuscular administration of which leads to a dramatic improvement. If dystonia does not resolve after two injections, it is recommended to try a benzodiazepine (eg, lorazepam). If dystonia recurs during ongoing antipsychotic therapy, a fixed dose of an anticholinergic drug should be administered for 2 weeks.
Russian authors recommend the use of the following options for acute dystonia:
Discontinuation of a typical antipsychotic drug or reduction in its dose
Transferring the patient to an atypical antipsychotic
Prescription of amantadine sulfate (PC-Merz) intravenously by drip for 5 days, followed by switching to taking tablets for 1 month; if dystonic symptoms return, continue taking
Prescription of an anticholinergic drug: trihexyphenidyl (cyclodol) or biperiden (akineton)
Purpose of vitamin B6
Prescription of benzodiazepines (diazepam)
Administration of aminazine intramuscularly and 20% caffeine solution subcutaneously
For generalized dystonias - simultaneous administration of aminazine or tizercin intramuscularly and antiparkinsonian correctors (akineton) also intramuscularly
Some Russian and Western sources recommend intravenous administration of antihistamines (diphenhydramine), caffeine-sodium benzoate, or barbiturates in severe cases.
Dystonia associated with abrupt withdrawal of a neuroleptic requires its re-prescription until hyperkinesis decreases or disappears completely, after which the dose of the drug is gradually reduced.
There are two main strategies in the treatment of acute akathisia: the traditional approach is to reduce the dose of the antipsychotic taken or switch the patient to a low-potency or atypical antipsychotic; Another strategy is the use of certain medications that are effective for akathisia. The most widely used of these are beta blockers, anticholinergics, clonidine, and benzodiazepines. Less commonly prescribed drugs such as amantadine, buspirone, piracetam and amitriptyline may be used in treatment-resistant cases.
Although anticholinergics have been shown to be effective in neuroleptic parkinsonism and dystonia, their clinical usefulness in akathisia remains unproven; preference may be given to them in cases where patients simultaneously experience symptoms of akathisia and parkinsonism. Lipophilic beta-blockers, such as propranolol, are among the most effective agents in the treatment of akathisia. Benzodiazepines also have some effectiveness, presumably due to their nonspecific antianxiety and sedative properties. 5-HT2 receptor blockers, in particular ritanserin, cyproheptadine, the antidepressants mianserin and (in low doses) mirtazapine, have also proven effective in treating akathisia. Valproates, gabapentin, pregabalin, weak opioids (codeine, hydrocodone, propoxyphene), vitamin B6 are also effective for akathisia.
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