Syndrome of movement disorders: causes, symptoms, diagnosis, treatment, prognosis. Disease Symptoms - Movement Disorders Causes of Movement Disorders
Each disease of the National Assembly is characterized by certain symptoms and syndromes, the identification of which allows you to determine the location of the lesion of the National Assembly (to establish a topical diagnosis). A symptom is understood as a sign of a disease, a syndrome in neurology is a set of persistent symptoms characterized by a certain pathological condition of the nervous system and united by their common passage. In case of damage or diseases of the nervous system, a person develops disorders in the form of motor, sensory, coordination, mental, vegetative, and other disorders.
Traffic - a manifestation of vital activity that provides the possibility of active interaction of both the constituent parts and the whole organism with the environment. Movement can be involuntary (reflex, unconscious) and voluntary (conscious). The main formation that provides the regulation of voluntary movements is the pyramidal system, which connects the motor centers of the cerebral cortex with the motor nuclei of the cranial nerves and the motor (motor neurons) of the anterior horns of the spinal cord in the cortico-muscular path.
involuntary motor responses are unconditional and occur in response to pain, sound, light, and other irritations and muscle strains. Voluntary motor responses arise as a result of the implementation of certain motor programs and are carried out with muscle contraction.
Motor disorders are manifested by damage in the connection between the motor area of the cerebral cortex (anterior central gyrus) and muscles, as well as damage to the cortical-muscular pathway. At the same time, regardless of the level at which the connection is broken, the muscle loses its ability to contract and paralysis develops. Paralysis- complete absence of voluntary movements. The nature of paralysis depends on which motor neuron is damaged - central or peripheral.
When the central (first) motor neuron is damaged, a central or spastic paralysis. More often, central paralysis occurs when there is a violation of cerebral circulation and is characterized by:
1) increased muscle tone (muscle hypertension or spasticity),
2) high tendon and periosteal reflexes hyperreflexia,
3) pathological extensor and flexion reflexes,
4) clonuses - rhythmic, repeated, not long
damped contractions of any muscle group during
certain methods of calling,
5) protective reflexes - involuntary movements, expressed in flexion or extension of a paralyzed limb when it is irritated (prick, cooling, etc.),
6) involuntary friendly movements in response to
purposeful or involuntary movement - synkinesis,
7) a lesion in the region of the brain stem leads to the development
alternating syndromes: a combination of FMN pathology on the side of the pathological focus and spastic hemiplegia on the opposite side.
If the peripheral (second; motor - neuron) is damaged, peripheral or flaccid paralysis, which is characterized by:
1) decrease or loss of muscle tone - hypotension or muscle atony,
2) malnutrition of muscles - atrophy of paralyzed muscles,
3) hyporeflexia - a decrease or areflexia by the absence of tendon reflexes,
4) violation of electrical excitability - the reaction of rebirth.
With flaccid paralysis, there are not only voluntary, but also reflex movements. If there are no sensory disorders in flaccid paralysis, then the cells of the anterior horn of the spinal cord are affected, which is characterized by fibrillar twitching of the mouse of the rebirth reaction and the early appearance of muscle atrophy. Damage to the anterior spinal roots is characterized by fascicular muscle twitching, areflexia and muscle atony in the area of innervation. If a sensory disturbance is added to the movement disorders, this means that the entire peripheral nerve is damaged.
Damage to the peripheral nerve m.b. incomplete, then the patient develops muscle weakness. This phenomenon of partial movement disorders - a decrease in muscle volume and strength is called paresis. Paresis of the muscles of one limb is called monoparesis, two limbs - paraparesis, three - triparesis, four - tetraparesis. With a half lesion of the body (right arm and right leg), hemiparesis develops. Localization of the lesion causes pathological changes at various levels: if the spinal cord is affected in its diameter above the cervical thickening (inflammation, trauma, tumor), then the patient develops spastic tetraplegia,
The term plegia correlates with the concept of paralysis and denotes the complete absence of contractions of the corresponding muscles. With mildly disturbed muscle tone, the phenomena of apraxia are noted, the impossibility due to the inability to perform purposeful practical actions for self-service.
Movement disorders may be expressed and impaired coordination - ataxias, which is of two types: static and dynamic. Static ataxia- imbalance when standing (in statics), checked by stability in the Romberg test, dynamic ataxia- imbalance in the disproportion of the motor act (shaky, uncertain gait with arms wide apart). Ataxia occurs with pathology of the cerebellum and vestibular apparatus. Other cerebellar disorders: nystagmus- rhythmic twitching of the eyeballs, more often when looking to the side; scanned speech- jerky speech with accents at certain intervals; misses- overshooting when performing a purposeful movement, and diadochokinesis- uncoordinated movements of the hands during their rotation in an extended position (the hand lags behind on the side of the lesion); dysmetria- violation of the amplitude of movements; dizziness; intentional trembling- trembling (tremor) when performing precise movements. Movement disorders are sometimes accompanied by hyperkinesias, involuntary movements devoid of physiological significance. Various types of hyperkinesis occur in the pathology of the extrapyramidal system.
Hyperkinesias include:
- convulsions- involuntary contractions clonic- rapidly alternating muscle contractions and tonic- long-term muscle contractions, convulsions - the result of irritation of the cortex or brain stem;
- athetosis- slow artsy (worm-like) contractions of the muscles of the limbs (usually fingers and toes), appear in the pathology of the cortex;
- jitter- involuntary rhythmic oscillatory movements of the limbs or head with damage to the cerebellum and subcortical formations;
- chorea - fast erratic movements, similar to deliberate antics, dancing;
- tick - short-term monotonous clonic twitches of individual muscle groups (often the face);
- facial hemispasm - attacks of convulsive twitching of the muscles of one half of the face;
- myoclonus - fast, lightning-fast contractions of individual muscle groups.
Lesions of the spinal cord at its various levels, along with motor disorders, are also manifested by sensory disorders.
Sensitivity - the ability of the organism to perceive irritations from the environment or from its own tissues or organs. Sensory receptors are classified into exteroreceptors(pain, temperature, tactile receptors); proprioreceptors(located in muscles, tendons, ligaments, joints), providing information about the position of the limbs and torso in space, the degree of muscle contraction; interoreceptors(located in internal organs).
Interoceptive sensitivity they call sensations arising from irritation of internal organs, vessel walls, etc. It is connected with the sphere of autonomic innervation. Allocate also special sensitivity, arising in response to irritation from the outside of the senses: sight, hearing, smell, taste.
The most common sign of sensory irritation is pain. Pain- this is a real subjective sensation due to the applied irritation or pathology in tissues or organs. With the defeat of the nerve fibers that carry out somatic innervation, there are somatalgia. Such pains are permanent or periodic, not accompanied by vegetative manifestations. When involved in the process of fibers of autonomic sensory innervation, develop sympathy. These pains are deep, pressing, of a permanent or periodic nature, accompanied by vegetative reactions - goosebumps, sweating, trophic disorders. Pain of girdle nature or going along the limb received; title radicular pain. Causalgia- burning pain. Pain can wear local, projection, irradiating, reflected phantom, reactive character.
local pain occurs in the area of existing painful irritation. Projection pain - the localization of pain does not coincide with the site of the existing irritation (with a bruise of the elbow joint, pain in 4-5 fingers of the hand). irradiating pain that spreads from one branch of the irritated nerve to another. Reflected pain is a manifestation of painful irritation in diseases of the internal organs. Phantom pain occurs in people who have undergone amputation, in the stump of cut nerves. Reactive pain - pain in response to compression or tension of a nerve or root.
Other types of sensory impairment: anesthesia- complete lack of sensitivity; hypoesthesia- reduced sensitivity; hyperesthesia- Hypersensitivity, which in most cases is accompanied by pain in the zone of innervation (neuralgia). paresthesia- a feeling of tingling, "crawling", numbness. Dysesthesia- perverted perception of stimuli, when tactile is perceived as painful, etc. Polyesthesia- a type of perversion of pain sensitivity, in which a single irritation is perceived as multiple. Hemianesthesia- loss of sensation in one half of the body, one limb - monoanesthesia, in the legs and lower body - paraanesthesia. hypoesthesia- lowering the perception of both the entire sensitivity and its individual types. Hyperpathy- a condition in which even the slightest irritation exceeds the threshold of excitability and is accompanied by pain and a long aftereffect. Senestopathy- a variety of painful, long-term disturbing patients with sensations of burning, pressure, constriction, etc., which do not have obvious organic causes for their occurrence. Violation of some types of sensitivity while maintaining others, is called dissociated disorders.
Disorders of sensitivity of the peripheral type may be. neural- violation of all types of sensitivity in the area supplied by the affected nerve; polyneuritic symmetrical disorders in the distal extremities; radicular- violation of all types of sensitivity in the zone of the corresponding dermatomes.
Neuro-psychic activity. It includes speech, thinking, memory, complex motor skills (praxis), comprehension of various objects of the external world (gnosia), etc.
Speech is the ability to pronounce and understand words and phrases, to comprehend them, connecting them with certain concepts.
Aphasia- violation of speech due to damage to the cortical centers of analysis and synthesis of words within one hemisphere of the left in right-handers and right - in left-handers. Aphasia m.b. sensory, motor, amnestic, total.
Sensory aphasia consists in a violation of the understanding of oral speech due to the defeat of the feeding center of the sound images of words, but the speech is preserved. This center is located in the temporal region of the brain. His defeat also leads to such a violation of speech functions as reading.
motor aphasia- violation of oral speech due to damage to the cortical center of motor speech automatisms, the patient understands the speech addressed to him. The center is located in the left frontal lobe (in right-handers). In such patients, the function of writing is also upset.
Amnestic aphasia- violation of the ability to name familiar objects, with knowledge of their purpose. The speech of such patients is poor in nouns, they forget the names of surrounding things, objects, etc. The syndrome is often combined with sensory aphasia, auditory memory is impaired. The cortical center is located at the junction of the temporal, occipital and parietal lobes of the left hemisphere (in right-handers).
Total aphasia- violation of writing, all types of speech and its understanding (occurs with extensive lesions).
Alexia- violation of reading and reading comprehension due to the defeat of the center for storing written images of speech. The lesion is in the parietal region, combined with sensory aphasia.
dysarthria- occurs with paralysis or paresis of the articulatory apparatus (usually the tongue), speech becomes illegible, incomprehensible.
Agraphia- writing disorder due to damage to the cortical center of motor automatisms (in the frontal region). It is combined with motor aphasia, difficulty in understanding what is written by the patient himself.
Apraxia- violation of purposeful motor skills due to damage to the cortical center of complex actions. Patients cannot fasten buttons, comb their hair, eat with a spoon, etc. Often the sequence of actions is disturbed, superfluous, unnecessary movements appear (parapraxia), or the patient gets stuck on some kind of movement (perseveration). Apraxia occurs when the cortex is damaged in the parietal-temporal-occipital region.
Allocate motor, ideational and constructive apraxia. At motor apraxia goal-directed movements by oral order and by imitation are upset. At ideational apraxia- disorder of movements according to the oral order and safety of actions on imitation. Constructive Apraxia- this is a special type of movement disorder, when the patient is not able to construct a whole from parts, arrange letters, numbers, there are no spatial relationships, etc.
agnosia- violation of recognition processes with preservation or slight change in the perceiving function of the sense organs.
Gnosis closely related to memory. There are the following types of agnosia:
- visual ("mental blindness")- impaired recognition of objects and things, with the preservation of vision, the lesion in the occipital region;
- auditory ("mental deafness")- disorder of recognition of the outside world by characteristic sounds (clock ticking while maintaining hearing, the lesion in the temporal region, combined with sensory aphasia;
- odor agnosia- violation of the recognition of odorous substances by a characteristic odor with the preservation of the olfactory function. The focus is localized in the deep parts of the temporal lobe;
- agnosia of taste- loss of the ability to recognize familiar substances with the preservation of taste sensations, the focus is in the central gyrus;
- astereognosis- not recognizing objects by touch with sufficient preservation of deep and superficial sensitivity, focus in the parietal lobe;
- agnosia of parts of one's own body- violation of the body scheme, confuses the left and right sides of his body, feels the presence of three legs, four arms, etc., the focus is in the interparietal sulcus.
Disorders of consciousness.
Consciousness is the highest form of reflection of reality, which is a set of human mental processes.
Types of impaired consciousness are conditionally divided into syndromes of turning off consciousness and syndromes of clouding of consciousness.
Syndromes of turning off consciousness: stupor("load") - increasing the threshold of perception. Speech contact with the patient is filled with difficulty due to lethargy, lethargy, disorientation, impaired attention, etc. The condition is characteristic of a brain tumor.
Sopor- a condition in which patients do not respond to verbal appeals, are motionless, although with loud repeated appeals they open their eyes, try to pronounce the words, but soon melt away to respond to any stimuli. Unconditioned and deep reflexes are preserved. The condition is characteristic of a tumor, TBI, and other conditions.
Coma - the deepest inclusion of consciousness with the absence of unconditioned and conditioned reflexes (with the exception of vital ones. The state of coma is typical for TBI, cerebral stroke, severe intoxication, infectious diseases.
Confusion Syndromes: Delirious Syndrome- violation of orientation in one's own personality. Visual, auditory, tactile hallucinations are characteristic. The syndrome manifests itself in mental illness (schizophrenia), alcohol intoxication ("delirious tremens").
Twilight clouding of consciousness- a sharp "narrowing of the field of consciousness", a twilight state in the form of hallucinatory manifestations of anxiety. fear, anger, etc. or automatic nocturnal reactions like sleepwalking.
Trance- a short-term condition in which the patient performs impulsive purposeful actions, which he does not remember in the future. Twilight state and trance are characteristic of epilepsy, TBI.
Various types of disorders of higher nervous activity are observed in patients with cerebrovascular accidents (strokes), tumors, abscesses, intoxications, inflammation of the meninges, etc.
Similar information.
Content
Introduction
1. Movement disorders
2. Pathology of speech. Organic and functional speech disorders
Conclusion
Bibliography
Introduction
Speech as a specific mental process develops in close unity with motor skills and requires the fulfillment of a number of necessary conditions for its formation, such as: anatomical safety and sufficient maturity of those brain systems that are involved in the speech function; preservation of kinesthetic, auditory and visual perception; a sufficient level of intellectual development that would provide the need for verbal communication; normal structure of the peripheral speech apparatus; adequate emotional and speech environment.
The occurrence of speech pathology (including cases of a combination of such disorders with movement disorders) is due to the fact that, on the one hand, its formation is caused by the presence of varying degrees of severity of organic lesions of individual cortical and subcortical structures of the brain involved in providing speech functions, on the other hand, secondary underdevelopment or delayed "maturation" of the premotor-frontal and parietal-temporal cortical structures, disturbances in the rate and nature of the formation of visual-auditory and auditory-visual-motor nerve connections. With motor disorders, the afferent effect on the brain is distorted, which in turn enhances existing cerebral dysfunctions or causes new ones to appear, leading to asynchronous activity of the cerebral hemispheres.
Based on studies of the causes of these disorders, we can talk about the relevance of considering this problem. The topic of the essay is devoted to the consideration of the causes and types of speech pathologies and movement disorders.
1. Movement disorders
If we talk about the causes of movement disorders, it can be noted that most of them arise as a result of a violation of the functional activity of mediators in the basal ganglia, the pathogenesis can be different. The most common causes are degenerative diseases (congenital or idiopathic), possibly triggered by medication, organ system failure, CNS infections, or basal ganglia ischemia. All movements are carried out through the pyramidal and parapyramidal pathways. As for the extrapyramidal system, the main structures of which are the basal nuclei, its function is to correct and refine movements. This is achieved mainly through influences on the motor areas of the hemispheres through the thalamus. The main manifestations of damage to the pyramidal and parapyramidal systems are paralysis and spasticity.
Paralysis can be complete (plegia) or partial (paresis), sometimes it is manifested only by the awkwardness of the hand or foot. Spasticity is characterized by an increase in the tone of the limb according to the "jackknife" type, increased tendon reflexes, clonus and pathological extensor reflexes (for example, the Babinski reflex). It can also be manifested only by the awkwardness of movements. Frequent symptoms also include spasms of the flexor muscles, which occur as a reflex to constant uninhibited impulses from skin receptors.
Correction of movements is also provided by the cerebellum (The lateral sections of the cerebellum are responsible for the coordination of movements of the limbs, the middle sections are responsible for postures, gait, body movements. Damage to the cerebellum or its connections is manifested by intentional tremor, dysmetria, adiadochokinesis and a decrease in muscle tone.), mainly through influences on the vestibulospinal path, as well as (with switching in the nuclei of the thalamus) to the same motor areas of the cortex as the basal nuclei (motor disorders that occur when the basal nuclei are damaged (extrapyramidal disorders), can be divided into hypokinesia (a decrease in the volume and speed of movements; an example is Parkinson's disease or parkinsonism of another origin) and hyperkinesis (excessive involuntary movements; an example is Huntington's disease). Tics also belong to hyperkinesis.).
With certain mental illnesses (primarily with catatonic syndrome), one can observe conditions in which the motor sphere receives some autonomy, specific motor acts lose their connection with internal mental processes, cease to be controlled by the will. In this case, the disorders become similar to neurological symptoms. It should be recognized that this similarity is only external, since, unlike hyperkinesis, paresis, and motor coordination disorders in neurological diseases, movement disorders in psychiatry have no organic basis, are functional and reversible.
Those suffering from a catatonic syndrome cannot somehow psychologically explain the movements they make, they are not aware of their painful nature until the moment of copying psychosis. All disorders of the motor sphere can be divided into hyperkinesia (excitation), hypokinesia (stupor) and parakinesia (distortion of movements).
Excitation, or hyperkinesia, in mentally ill patients is a sign of an exacerbation of the disease. In most cases, the patient's movements reflect the richness of his emotional experiences. He may be controlled by the fear of persecution, and then he flees. In a manic syndrome, the basis of his motor skills is an indefatigable thirst for activity, and in hallucinatory states, he may look surprised, strive to draw the attention of others to his visions. In all these cases, hyperkinesia acts as a symptom secondary to painful mental experiences. This type of arousal is called psychomotor.
In catatonic syndrome, movements do not reflect the internal needs and experiences of the subject, therefore, excitation in this syndrome is called purely motor. The severity of hyperkinesia often indicates the severity of the disease, its severity. However, at times there are severe psychoses with arousal limited to the bed.
Stupor - a state of immobility, an extreme degree of motor inhibition. Stupor can also reflect vivid emotional experiences (depression, asthenic affect of fear). In catatonic syndrome, on the contrary, stupor is devoid of internal content, meaningless. The term "substupor" is used to refer to states accompanied by only partial inhibition. Although stupor implies a lack of motor activity, in most cases it is considered a productive psychopathological symptom, since it does not mean that the ability to move is irreversibly lost. Like other productive symptoms, stupor is a temporary condition and responds well to treatment with psychotropic drugs.
The catatonic syndrome was originally described by KL Kalbaum (1863) as an independent nosological unit, and is currently considered as a symptom complex. One of the important features of the catatonic syndrome is the complex, contradictory nature of the symptoms. All motor phenomena are devoid of meaning and are not associated with psychological experiences. Characterized by tonic muscle tension. Catatonic syndrome includes 3 groups of symptoms: hypokinesia, hyperkinesia and parakinesia.
Hypokinesias are represented by the phenomena of stupor and substupor. Complex, unnatural, sometimes uncomfortable postures of patients attract attention. There is a sharp tonic contraction of the muscles. This tone allows patients sometimes for some time to hold any position that the doctor gives them. This phenomenon is called catalepsy, or waxy flexibility.
Hyperkinesia in catatonic syndrome is expressed in bouts of excitement. Characterized by the commission of meaningless, chaotic, non-purposeful movements. Motor and speech stereotypes (rocking, bouncing, waving arms, howling, laughing) are often observed. An example of speech stereotypes are verbigerations, which are manifested by the rhythmic repetition of monotonous words and meaningless sound combinations.
Parakinesias are manifested by strange, unnatural movements, such as frilly, mannered facial expressions and pantomime.
With catatonia, a number of echo symptoms are described: echolalia (repeating the words of the interlocutor), echopraxia (repetition of other people's movements), echomimicry (copying the facial expressions of others). These symptoms can occur in the most unexpected combinations.
It is customary to distinguish lucid catatonia, which occurs against the background of a clear consciousness, and oneiroid catatonia, accompanied by clouding of consciousness and partial amnesia. With the outward similarity of the set of symptoms, these two conditions differ significantly in course. Oneiroid catatonia is an acute psychosis with dynamic development and a favorable outcome. Lucid catatonia, on the other hand, is a sign of remission-free malignant variants of schizophrenia.
Hebephrenic syndrome has a significant similarity with catatonia. The predominance of movement disorders with unmotivated, meaningless actions is also characteristic of hebephrenia. The very name of the syndrome indicates the infantile nature of the behavior of patients.
Speaking of other syndromes accompanied by arousal, it can be noted that psychomotor agitation is one of the frequent components of many psychopathological syndromes.
Manic excitation differs from catatonic in the purposefulness of actions. Facial expressions express joy, patients seek to communicate, talk a lot and actively. With pronounced arousal, the acceleration of thinking leads to the fact that not everything said by the patient is understandable, but his speech is never stereotyped.
Agitated depression is manifested by a combination of severe melancholy and anxiety. Facial expressions reflect suffering. Lamentations, crying without tears are characteristic. Often, anxiety is accompanied by nihilistic megalomaniac delusions with ideas of the death of the world (Cotard's syndrome). Acute hallucinatory-delusional states are also often expressed by psychomotor agitation. Acute hallucinosis can also be manifested by psychomotor agitation.
Quite often, the cause of psychomotor agitation is clouding of consciousness. The most common among the syndromes of clouding of consciousness - delirium - is manifested not only by disorientation and pig-like true hallucinations, but also by extremely pronounced arousal. Patients tend to run away from the hallucinatory images pursuing them, attack them, try to defend themselves with a knife, throw heavy objects, fleeing, they can go out the window.
The amental syndrome is characterized by an even greater severity of the condition. Patients are emaciated, unable to get out of bed. Their movements are chaotic, uncoordinated (yactation): they wave their arms, make meaningless cries, crumple in their hands and tear the sheet, shake their heads.
Oneiric stupefaction is manifested by the catatonic symptoms described above. With twilight stupefaction, there are both automated actions that are safe for others, and attacks of ridiculous chaotic excitement, often accompanied by violent anger, brutal aggression.
Another variant of epileptic arousal is history attacks, although not accompanied by clouding of consciousness and amnesia, but also often leading to dangerous, aggressive actions.
The danger of psychomotor agitation forced psychiatrists until the middle of the twentieth century. often use various means of restraint (belts, straitjackets, isolation chambers). The appearance at the beginning of the century of powerful barbiturates, and especially the introduction of new psychotropic drugs into practice at the end of the 50s, made it possible to almost completely abandon the use of restraint measures. Currently, various antipsychotics are used to relieve psychomotor agitation, and benzodiazepine tranquilizers are somewhat less common.
Stupor is less common in psychiatric practice than excitement. In addition to the catatonic syndrome, it can be a manifestation of severe depression, apatico-abulic syndrome and hysteria.
Among other syndromes accompanied by stupor, the presence of a depressive stupor, closely related in its manifestations to the affect of melancholy, is noted. The face of the sick expresses suffering. The whole state is characterized by integrity, the absence of paradoxes.
Apathetic stupor is observed relatively rarely. The face of such patients is amimic, expresses indifference. In apathico-abulic syndrome there is no suppression of desires, so patients never refuse food. From prolonged inactivity, they become very stout. Unlike patients with catatonic stupor, they express dissatisfaction aloud if someone violates their comfort, makes them get out of bed, wash or cut their hair. The causes of apathetic stupor are schizophrenia or damage to the frontal lobes of the brain.
Hysterical stupor, like hysterical excitement, appears immediately after the occurrence of a traumatic situation. The clinical picture can take the most unexpected forms.
In addition to hysterical, psychogenic stuporous states are described in life-threatening situations. Stupor in most cases is not a socially dangerous condition, since motor inhibition is only one of the manifestations of any syndrome.
2. Pathology of speech. Organic and functional speech disorders
The problem of the etiology of speech disorders has gone through the same path of historical development as the general doctrine of the causes of disease states.
Since ancient times, there have been two points of view - brain damage or violations of the local speech apparatus, as the causes of disorders.
Despite this, only in 1861, when the French physician Paul Broca showed the presence in the brain of a field specifically related to speech, and associated the loss of speech with its defeat. In 1874, a similar discovery was made by Wernicke: a connection was established between understanding and the preservation of a certain area of the cerebral cortex. Since that time, the connection of speech disorders with morphological changes in certain parts of the cerebral cortex has become proven.
The most intensive questions of the etiology of speech disorders began to be developed from the 20s of this century. During these years, domestic researchers made the first attempts to classify speech disorders depending on the causes of their occurrence. So, S. M. Dobrogaev (1922) singled out “diseases of higher nervous activity”, pathological changes in the anatomical speech apparatus, lack of education in childhood, as well as “general neuropathic conditions of the body” among the causes of speech disorders.
M. E. Khvattsev for the first time divided all the causes of speech disorders into external and internal, emphasizing their close interaction. He also singled out organic (anatomical, physiological, morphological), functional (psychogenic), socio-psychological and neuropsychiatric causes.
Underdevelopment and damage to the brain in the prenatal period were attributed to organic causes. They singled out organic central (brain lesions) and organic peripheral causes (lesion of the organ of hearing, cleft palate and other morphological changes in the articulatory apparatus). M. E. Khvattsev explained the functional reasons by the teachings of I. P. Pavlov about violations of the ratio of the processes of excitation and inhibition in the central nervous system. He emphasized the interaction of organic and functional, central and peripheral causes. He attributed mental retardation, impaired memory, attention, and other disorders of mental functions to neuropsychiatric causes.
The important role of M.E. Khvattsev also attributed socio-psychological reasons, understanding them as various adverse environmental influences. Thus, he was the first to substantiate the understanding of the etiology of speech disorders on the basis of a dialectical approach to assessing causal relationships in speech pathology.
The cause of speech disorders is understood as the impact on the body of an external or internal harmful factor or their interaction, which determine the specifics of a speech disorder and without which the latter cannot occur.
The motor mechanism of speech is also provided by the following higher brain structures:
With damage to the subcortical-cerebellar nuclei and pathways that regulate muscle tone and the sequence of muscle contractions of the speech muscles, synchrony (coordination) in the work of the articulatory, respiratory and vocal apparatus, as well as the emotional expressiveness of speech, there are individual manifestations of central paralysis (paresis) with violations of muscle tone, strengthening of individual unconditioned reflexes, as well as with a pronounced violation of the prosodic characteristics of speech - its pace, smoothness, loudness, emotional expressiveness and individual timbre.
The defeat of the conduction systems that ensure the conduction of impulses from the cerebral cortex to the structures of the underlying functional levels of the motor apparatus of speech (to the nuclei of the cranial nerves located in the brain stem) causes central paresis (paralysis) of the speech muscles with an increase in muscle tone in the muscles of the speech apparatus, strengthening of unconditioned reflexes and the appearance of reflexes of oral automatism with a more selective nature of articulatory disorders.
With damage to the cortical parts of the brain, which provide both a more differentiated innervation of the speech muscles and the formation of speech praxis, various central motor speech disorders occur.
Speech disorders often occur with various mental traumas (fear, feelings of separation from loved ones, a long-term traumatic situation in the family, etc.). This delays the development of speech, and in some cases, especially with acute mental trauma, causes psychogenic speech disorders in the child: mutism, neurotic stuttering. These speech disorders, according to the classification of M. E. Khvattsev, can conditionally be classified as functional.
Functional speech disorders also include disorders associated with adverse effects on the child's body: general physical weakness, immaturity due to prematurity or intrauterine pathology, diseases of internal organs, rickets, metabolic disorders.
Thus, any general or neuropsychiatric disease of a child in the first years of life is usually accompanied by a violation of speech development. Hence, it is legitimate to distinguish between defects in formation and defects in formed speech, considering the age of three as their conditional subdivision.
The leading place in the perinatal pathology of the nervous system is occupied by asphyxia and birth trauma.
The occurrence of intracranial birth trauma and asphyxia (oxygen starvation of the fetus at the time of birth) is facilitated by a violation of intrauterine development of the fetus. Birth trauma and asphyxia exacerbate fetal brain development disorders that occurred in utero. Birth trauma leads to intracranial hemorrhage and death of nerve cells. Intracranial hemorrhages can also capture the speech zones of the cerebral cortex, which entails various speech disorders of cortical origin (alalia). In premature babies, intracranial hemorrhages occur most easily as a result of the weakness of their vascular walls.
In the etiology of speech disorders in children, immunological incompatibility of the blood of the mother and fetus (according to the Rh factor, the ABO system and other erythrocyte antigens) can play a certain role. Rhesus or group antibodies, penetrating the placenta, cause the breakdown of fetal red blood cells. Under the influence of a substance toxic to the central nervous system - indirect bilirubin - the subcortical parts of the brain, auditory nuclei are affected, which leads to specific disorders of the sound-producing side of speech in combination with hearing impairment. With intrauterine lesions of the brain, the most severe speech disorders are noted, combined, as a rule, with other polymorphic developmental defects (hearing, vision, musculoskeletal system, intelligence). At the same time, the severity of speech disorders and other developmental defects largely depends on the time of brain damage in the prenatal period.
Infectious and somatic diseases of the mother during pregnancy can lead to uteroplacental circulation disorders, nutritional disorders and oxygen starvation of the fetus. Violations of intrauterine development of the fetus - embryopathies - can occur in connection with viral diseases, medication, ionizing radiation, vibration, alcoholism and smoking during pregnancy. The adverse effect of alcohol and nicotine on offspring has been noted for a long time.
Toxicosis of pregnancy, prematurity, non-prolonged asphyxia during childbirth cause mild minimal organic brain damage (children with minimal brain dysfunction - MMD).
At present, with mild cerebral insufficiency, a special type of mental dysontogenesis is distinguished, which is based on the superior age-related immaturity of individual higher cortical functions. With minimal brain dysfunction, there is a delay in the rate of development of the functional systems of the brain that require integrative activity for their implementation: speech, behavior, attention, memory, spatio-temporal representations and other higher mental functions.
Children with minimal brain dysfunction are at risk for developing speech disorders.
Speech disorders can also occur as a result of the impact of various adverse factors on the child's brain and at subsequent stages of its development. The structure of these speech disorders is different depending on the time of exposure to harmfulness and localization of brain damage. Hereditary factors also play a certain role in the etiology of speech disorders in children. Often they are predisposing conditions that are realized in speech pathology under the influence of even minor adverse effects.
Thus, the etiological factors that cause speech disorders are complex and polymorphic. The most common combination of hereditary predisposition, unfavorable environment and damage or impaired brain maturation under the influence of various unfavorable factors.
When dwelling on the types of speech disorders, one should focus directly on the existing deviations and pathologies of speech associated with congenital or acquired causes of their occurrence.
Violation of sound pronunciation with normal hearing and intact innervation of the speech apparatus, or dyslalia, is one of the most common pronunciation defects. There are two main forms of dyslalia, depending on the location of the violation and the reasons for the defect in sound pronunciation; functional and mechanical (organic).
In cases where no organic disorders (peripherally or centrally conditioned) are observed, they speak of functional dyslalia. With deviations in the structure of the peripheral speech apparatus (teeth, jaws, tongue, palate), they speak of mechanical (organic) dyslalia. Functional dyslalia includes defects in the reproduction of speech sounds (phonemes) in the absence of organic disturbances in the structure of the articulatory apparatus. Causes of occurrence - biological and social: general physical weakness of the child due to somatic diseases; mental retardation (minimal brain dysfunction), delayed speech development, selective impairment of phonemic perception; unfavorable social environment that hinders the development of communication of the child.
Rhinolalia (violation of the timbre of the voice and sound pronunciation due to anatomical and physiological defects of the speech apparatus) differs in its manifestations from dyslalia in the presence of an altered nasalized timbre of the voice. Depending on the nature of the dysfunction of the palatopharyngeal closure, various forms of rhinolalia are distinguished. With an open form of rhinolalia, oral sounds become nasal. Functional open rhinolalia is due to various reasons. It is explained by the insufficient rise of the soft palate during phonation in children with sluggish articulation.
One of the functional forms is the "habitual" open rhinolalia. It occurs frequently after removal of adenoid lesions or, more rarely, as a result of post-diphtheria paresis, due to prolonged restriction of the mobile soft palate. Organic open rhinolalia can be acquired or congenital. Acquired open rhinolalia is formed during perforation of the hard and soft palate, with cicatricial changes, paresis and paralysis of the soft palate. The cause may be damage to the glossopharyngeal and vagus nerves, injuries, tumor pressure, etc. The most common cause of congenital open rhinolalia is congenital splitting of the soft or hard palate, shortening of the soft palate.
Dysarthria is a violation of the pronunciation side of speech, due to insufficient innervation of the speech apparatus.
The leading defect in dysarthria is a violation of the sound-producing and prosodic side of speech, associated with an organic lesion of the central and peripheral nervous systems.
Violations of sound pronunciation in dysarthria manifest themselves to varying degrees and depend on the nature and severity of the damage to the nervous system. In mild cases, there are separate distortions of sounds, "blurred speech", in more severe cases, distortions, substitutions and omissions of sounds are observed, the tempo, expressiveness, modulation suffer, in general, the pronunciation becomes slurred.
With severe lesions of the central nervous system, speech becomes impossible due to complete paralysis of the speech motor muscles. Such disorders are called anartria (a - the absence of a given sign or function, artron - articulation).
Dysarthric speech disorders are observed in various organic lesions of the brain, which in adults have a more pronounced focal character. Less pronounced forms of dysarthria can be observed in children without obvious movement disorders, who have undergone mild asphyxia or birth trauma, or who have a history of other mild adverse effects during fetal development or during childbirth.
In 1911, N. Gutzmann defined dysarthria as a violation of articulation and identified two of its forms: central and peripheral.
The initial study of this problem was carried out mainly by neuropathologists in the framework of focal brain lesions in adult patients. The works of M. S. Margulis (1926), who for the first time clearly delimited dysarthria from motor aphasia and divided it into bulbar and cerebral forms, had a great influence on the modern understanding of dysarthria. The author proposed a classification of cerebral forms of dysarthria based on the localization of the brain lesion.
The pathogenesis of dysarthria is determined by an organic lesion of the central and peripheral nervous system under the influence of various unfavorable external (exogenous) factors affecting the prenatal period of development, at the time of childbirth and after birth. Among the causes of great importance are asphyxia and birth trauma, damage to the nervous system during hemolytic disease, infectious diseases of the nervous system, craniocerebral injuries, less often - cerebrovascular accidents, brain tumors, malformations of the nervous system, for example, congenital aplasia of the nuclei of the cranial nerves. (Mobius syndrome), as well as hereditary diseases of the nervous and neuromuscular systems.
Clinical and physiological aspects of dysarthria are determined by the location and severity of brain damage. The anatomical and functional relationship in the location and development of motor and speech zones and pathways determines the frequent combination of dysarthria with motor disorders of various nature and severity.
Sound pronunciation disorders in dysarthria occur as a result of damage to various brain structures necessary to control the motor mechanism of speech (peripheral motor nerves to the muscles of the speech apparatus; nuclei of these peripheral motor nerves located in the brain stem; nuclei located in the trunk and in the subcortical regions of the brain) . The defeat of these structures gives a picture of peripheral paralysis (paresis): nerve impulses do not reach the speech muscles, metabolic processes in them are disturbed, the muscles become lethargic, flabby, their atrophy and atony are observed, as a result of a break in the spinal reflex arc, reflexes from these muscles disappear, sets in. areflexia.
Voice disorders are also referred to as speech disorders. Violation of the voice is the absence or disorder of phonation due to pathological changes in the vocal apparatus. There are two main terms for the pathology of the voice: aphonia - the complete absence of voice and dysphonia - partial violations of pitch, strength and timbre.
Voice disorders associated with various diseases of the vocal apparatus are common in both adults and children. The pathology of the larynx in children has increased over the past two decades, which is associated with the expansion of resuscitation activities.
Voice disorders are divided into central and peripheral, each of them can be organic and functional. Most of the violations manifest themselves as independent, the causes of their occurrence are diseases and various changes in the vocal apparatus only. But they can also accompany other more severe speech disorders, entering the structure of the defect in aphasia, dysarthria, rhinolalia, and stuttering.
Voice pathology resulting from anatomical changes or chronic inflammation of the vocal apparatus is considered organic. Peripheral organic disorders include dysphonia and aphonia in chronic laryngitis, paresis and paralysis of the larynx, conditions after removal of tumors.
Central paresis and paralysis of the larynx depend on the damage to the cerebral cortex, bridge, medulla oblongata, pathways. In children, they are found in cerebral palsy.
The most common and diverse are functional voice disorders. They are not accompanied by inflammatory or any anatomical changes in the larynx. Peripheral functional disorders include phonasthenia, hypo- and hypertonic aphonia and dysphonia.
Phonasthenia - a violation of the voice in some cases, especially in the initial stages, is not accompanied by visible objective changes in the vocal apparatus. Phasthenia manifests itself in violation of the coordination of breathing and phonation, the inability to control the voice - to strengthen and weaken the sound, the appearance of detonation and a number of subjective sensations.
Hypotonic dysphonia (aphonia) is caused, as a rule, by bilateral myopathic paresis, i.e., paresis of the internal muscles of the larynx. They occur with some infections (ARVI, influenza, diphtheria), as well as with a strong voice strain. Pathology of the voice can manifest itself from mild hoarseness to aphonia with symptoms of voice fatigue, tension and pain in the muscles of the neck, neck and chest.
Hypertonic (spastic) voice disorders are associated with an increase in the tone of the laryngeal muscles with a predominance of tonic spasm at the time of phonation. The causes of their occurrence are not fully understood, but spastic dysphonia and aphonia develop in individuals who force their voice.
Rhinophonia and rhinolalia stand somewhat apart from other voice disorders, since their pathophysiological mechanism lies in the abnormal function of the soft palate of an organic or functional nature. With closed rhinophony, nasal consonants acquire oral resonance, vowels lose their sonority, and the timbre becomes unnatural.
Open rhinophony manifests itself in the pathological nasalization of all oral sounds, while the voice is weak, choked. Voice defects, in addition to impaired resonance, are due to the fact that the soft palate is functionally connected with the internal muscles of the larynx and affects the symmetry and tone of the vocal folds.
Functional voice disorders of central origin include functional or psychogenic aphonia. It arises suddenly as a reaction to a traumatic situation in persons prone to hysterical reactions, more often in girls and women.
Speech disorders include bradilalia and takhilalia. With these disorders, the development of both external and internal speech is disturbed. Speech is incomprehensible to others.
Bradilalia is a pathologically slow rate of speech. With bradylalia, the voice is monotonous, loses modulation, constantly maintains the same pitch, sometimes a nasal tone appears. The musical accent also changes when pronouncing individual syllables, the pitch of the voice fluctuates up or down. Non-verbal symptoms in bradilalia are expressed in violations of general motor skills, fine motor skills of the hands, fingers, facial muscles. Movements are slow, sluggish, insufficiently coordinated, incomplete in volume, motor awkwardness is observed. Amicable face. There are also features of mental activity: slowness and disorders of perception, attention, memory, thinking.
Tahilalia is a pathologically accelerated rate of speech. M. E. Khvattsev (1959) considered the main cause of takhilalia to be congenital motor speech insufficiency of the speech apparatus, as well as sloppy, uneven speech of others, lack of attention and timely correction of the child’s rapid speech. A. Liebmann distinguished between shortcomings in motor and acoustic perception that underlie takhilalia. G. Gutzman argued that this disorder is a consequence of a violation of perception. According to E. Freschels, accelerated speech occurs due to the fact that thoughts rush extremely quickly and one concept is replaced by the next before the first can be uttered. M. Nedolechny considered articulation deficiency to be the cause of accelerated speech, since patients have difficulty pronouncing unusual and long words.
Stuttering is a violation of the tempo-rhythmic organization of speech, due to the convulsive state of the muscles of the speech apparatus.
Alalia - the absence or underdevelopment of speech due to an organic lesion of the speech zones of the cerebral cortex in the prenatal or early period of a child's development. Intrauterine pathology leads to diffuse damage to the substance of the brain, birth traumatic brain injury and asphyxia of newborns cause more local disorders. Somatic diseases only exacerbate the impact of pathological causes of a neurological nature, which are leading.
Some authors (R. Cohen, 1888; M. Zeeman, 1961; R. Luhzinger, A. Saley, 1977, etc.) emphasize the role of heredity, family predisposition in the etiology of alalia. However, there is no convincing scientific data on the role of heredity in the origin of alalia in the literature. In recent years, the significant role of minimal brain damage (minimal brain dysfunction) has been emphasized in the occurrence of alalia.
Aphasia is a complete or partial loss of speech due to local lesions of the brain.
The causes of aphasia are cerebrovascular accidents (ischemia, hemorrhage), trauma, tumors, infectious diseases of the brain. Aphasia of vascular origin most often occurs in adults. As a result of rupture of cerebral aneurysms, thromboembolism caused by rheumatic heart disease, and traumatic brain injuries. Aphasia is often observed in adolescents and young people.
Aphasia occurs in about a third of cases of cerebrovascular accidents, with motor aphasia being the most common.
Aphasia is one of the most severe consequences of brain damage, in which all types of speech activity are systemically disturbed. The complexity of the speech disorder in aphasia depends on the location of the lesion. With aphasia, the implementation of different levels, sides, types of speech activity (oral speech, speech memory, phonemic hearing, speech understanding, written speech, reading, counting, etc.) is specifically systemically disturbed.
Acoustic-gnostic sensory aphasia was first described by the German psychiatrist Wernicke. He showed that aphasia, which he called sensory, occurs when the posterior third of the superior temporal gyrus of the left hemisphere is affected. A distinctive feature of this form of aphasia is a violation of the understanding of speech when perceiving it by ear.
Acoustic-mnestic aphasia occurs when the middle and posterior sections of the temporal region are affected (A. R. Luria, 1969, 1975; L. S. Tsvetkova, 1975). A.R. Luria believes that it is based on a decrease in auditory-speech memory, which is caused by increased inhibition of auditory traces. With the perception of each new word and its awareness, the patient loses the previous word. This disturbance also manifests itself in the repetition of a series of syllables and words.
Amnestic-semantic aphasia occurs when the parieto-occipital region of the speech-dominant hemisphere is affected. With damage to the parietal-occipital (or posterior lower-parietal) parts of the cerebral hemisphere, a smooth syntagmatic organization of speech is preserved, no searches for the sound composition of a word are noted, there are no phenomena of a decrease in auditory-speech memory or a violation of phonemic perception.
Afferent kinesthetic motor aphasia occurs when the secondary zones of the post-central and lower parietal regions of the cerebral cortex are damaged, located behind the central, or Roland, furrow.
Effective motor aphasia occurs when the anterior branches of the left middle cerebral artery are damaged. It is accompanied, as a rule, by kinetic apraxia, which is expressed in the difficulties of assimilation and reproduction of the motor program.
The defeat of the premotor parts of the brain causes pathological inertia of speech stereotypes, leading to sound, syllable and lexical permutations and perseveration, repetitions. Perseverations, involuntary repetitions of words, syllables, which are the result of the impossibility of timely switching from one articulatory act to another.
Dynamic aphasia occurs when the posterior frontal sections of the left hemisphere, dominant in speech, are affected, that is, the sections of the third functional block - the block of activation, regulation and planning of speech activity.
The main speech defect in this form of aphasia is the difficulty, and sometimes the complete impossibility of active deployment of the utterance. With a rough severity of the disorder, not only speech is noted, but also a general lack of initiative, there is a pronounced echolalia, and sometimes echopraxia.
In the aspect of speech pathologies, a violation of written speech is also considered. These include: alexia, dyslexia, agraphia, dysgraphia.
Dyslexia is a partial specific violation of the reading process, due to the lack of formation (violation) of higher mental functions and manifested in repetitive errors of a persistent nature.
The etiology of dyslexia is associated with the impact of biological and social factors. Dyslexia is caused by organic damage to the areas of the brain involved in the process of reading. Functional causes may be related to the impact of internal and external factors. Thus, both genetic and exogenous factors are involved in the etiology of dyslexia (pathology of pregnancy, childbirth, asphyxia, a “chain” of childhood infections, head injuries).
Dysgraphia is a partial specific violation of the writing process. This violation is due to the underdevelopment (disintegration) of higher mental functions that carry out the process of writing normally.
Conclusion
Based on the research experience of such scientists as P. Broca, Wernicke, K.L. Kalbaum, S.M. Dobrogaev, M.E. Khvattsev, L.S. Volkova, A.R. Luria, M. S. Margulis, A. Liebmann, G. Gutzman, E. Freshels, M. Nedolechny and others, who made a significant contribution to the study of the problems of speech and motor pathologies, modern trends (both theoretical and practical) in the field of studying the mechanisms of motor and speech disorders, it provides an opportunity not only to get a deeper and more thorough understanding of the essence of this problem, but also creates promising conditions for direct corrective and adaptive assistance to people suffering from these disorders. In order for assistance to be as effective as possible, it is necessary not only to know the essence of the mechanisms of mental processes and the action of motor skills, the mechanism of their violation. Specialists involved in the study of these problems need to constantly and continuously orient their activities towards preventing the occurrence of pathologies, as well as systematically monitor the state of impaired functions, preventive activities of disorders, and provide specific assistance in this area to patients.
List of used literature
1. Zharikov M.N., Tyulpin Yu.G. Psychiatry. – M.: Medicine, 2002.
2. Zeigarnik B.V. Pathopsychology. - M.: Moscow University Publishing House, 1986.
3. Liebmann A. Pathology and therapy of stuttering and tongue-tiedness. (St. Petersburg - 1901) / / Reader on speech therapy (extracts and texts). Textbook for students of higher and secondary educational institutions: In 2 vols. T.I / Ed. L.S. Volkova and V.I. Seliverstov. - M.: Humanit. ed. center VLADOS, 1997.
4. Speech therapy: Textbook for students defectol. fak. ped. universities / Ed. L.S. Volkova, S.N. Shakhovskaya. - M.: Humanit. ed. center VLADOS, 1998.
5. Luria.A.R. Stages of the traveled path//Scientific autobiography. - M.: Publishing House of Moscow. un-ta, 1982.
6. Neiman L.V., Bogomilsky M.R. Anatomy, physiology and pathology of the organs of hearing and speech / / Textbook. for stud. higher pedagogical textbook head. - M.: Humanit. ed. center VLADOS, 2003.
7. Jaspers K. General psychopathology// Per. with him. L. O. Akopyan, ed. doc. honey. Sciences VF Voitsekh and Ph.D. philosophy sciences O. Yu. Boytsova.- M.: Practice, 1997.
Speech therapy: Textbook for students defectol. fak. ped. universities / Ed. L.S. Volkova, S.N. Shakhovskaya. - M.: Humanit. ed. center VLADOS, 1998, p. 230.
Speech therapy: Textbook for students defectol. fak. ped. universities / Ed. L.S. Volkova, S.N. Shakhovskaya. - M.: Humanit. ed. center VLADOS, 1998, p. 243
Speech therapy: Textbook for students defectol. fak. ped. universities / Ed. L.S. Volkova, S.N. Shakhovskaya. - M.: Humanit. ed. center VLADOS, 1998, p. 248
Speech therapy: Textbook for students defectol. fak. ped. universities / Ed. L.S. Volkova, S.N. Shakhovskaya. - M.: Humanit. ed. center VLADOS, 1998, p.86.
Zeigarnik B.V. Pathopsychology. - M.: Moscow University Publishing House, 1986, p.180.
Speech therapy: Textbook for students defectol. fak. ped. universities / Ed. L.S. Volkova, S.N. Shakhovskaya. - M.: Humanit. ed. center VLADOS, 1998, p.93.
Neiman L.V., Bogomilsky M.R. Anatomy, physiology and pathology of the organs of hearing and speech / / Textbook. for stud. higher pedagogical textbook head. - M.: Humanit. ed. center VLADOS, 2003, p.177.
Speech therapy: Textbook for students defectol. fak. ped. universities / Ed. L.S. Volkova, S.N. Shakhovskaya. - M.: Humanit. ed. center VLADOS, 1998, p.93
Zeigarnik B.V. Pathopsychology. - M.: Moscow University Publishing House, 1986, p.184.
Speech therapy: Textbook for students defectol. fak. ped. universities / Ed. L.S. Volkova, S.N. Shakhovskaya. - M.: Humanit. ed. center VLADOS, 1998, p. 95.
Zeigarnik B.V. Pathopsychology. - M.: Moscow University Publishing House, 1986, p.187.
Speech therapy: Textbook for students defectol. fak. ped. universities / Ed. L.S. Volkova, S.N. Shakhovskaya. - M.: Humanit. ed. center VLADOS, 1998, p. 176.
Motor (motor) disorders can occur due to pathological changes in the muscular, skeletal or nervous systems. When trying to classify motor disorders, it quickly becomes clear that a disorder can be adequately characterized only by describing it in several planes. At the suggestion of WHO (WHO, 1980), pathophysiological signs (impairments) serve to describe any damage. Examples of this are paralysis or decreased sensitivity, in particular after a cerebral hemorrhage. A myriad of motor disorders have been described for CNS lesions alone (Freund, 1986; Kurlan, 1995). The traditional approach to ordering the variety of possible disorders is to distinguish between negative and positive symptoms. Negative symptoms are those in which normal function is lost, such as loss of normal mobility in paralysis, or limitation of motor coordination in damage to the cerebellum. The concept of "positive symptoms" includes pathological movements, such as hyperkinesis (abnormally increased motor skills, sometimes with involuntary movements), myoclonus (jerky contractions of individual muscles), tics (a sequence of coordinated movements that occurs most often involuntarily) or changes in muscle tone, such as rigidity (pathologically increased muscle tension).
AT DSM IV lists some disorders in which motor disturbances are an essential component. This is a stutter DSM IV 307.0), hyperactivity ( DSM IV 314.xx), Gilles de la Tourette's disorder ( DSM IV 307.23), vocal tick ( DSM IV 307.22), transient tick ( DSM IV 307.21), tick unspecified ( DSM IV 307.20) and stereotyped movement disorder ( DSM IV 307.3). These disorders, however, represent only a small and arbitrary part of the totality of motor disorders.
Data on pathophysiological signs in many cases allow only an approximate prediction of which motor functions can actually still be performed. Therefore, a direct test of functionality, such as the ability to walk or grasp, is mandatory. The loss or limitation of functionality is called, at the suggestion of the WHO, disabilities. The difficulty of describing motor disorders in the plane of functional limitations lies in the boundless multitude of possibilities for testing functions. A generally accepted taxonomy of motor functions does not currently exist. In cerebral motor disorders, attempts have often been made to derive some order of motor function from patterns of cerebral control of movement (eg, Brooks, 1990, and chapter 26).
In order to evaluate the limitation of a function, it is enough to compare specific possibilities with normal values. True, if it is necessary to describe the insufficiency (handicap) of a particular person, then one has to take into account the conditions of his life. The main consequence of any movement disorder is the actual decrease in professional and daily activity, and this can only be registered by observing the patient in his environment or using questionnaires. To enable inter-individual comparisons, attempts have often been made to develop standardized daily tasks. Can, for example, a patient walk a distance of 10 m without aids? Can the patient dress himself? In view of the wide variety of possible disorders, the choice of everyday tasks to be tested is always arbitrary. Without data on the limitation of the function of a particular patient, the description of a motor disorder will be incomplete at best. The loss of the little finger would hardly have hurt many people, but for the pianist it would mean the end of his professional life.
Motor disorders can be divided according to the type of their genesis into primary organic and psychogenic motor disorders. In primary organic movement disorders, pathological changes are observed in the muscular, skeletal, or nervous systems; in psychogenic movement disorders, the presence of such changes cannot be proven. But the mere absence of such evidence of an organic disorder does not yet allow us to conclude that the movement disorder is mentally conditioned. To do this, it should be shown that the occurrence or severity of a movement disorder is largely influenced by psychological or mental factors. Because even in many organic movement disorders (eg, dystonia, essential tremor, Parkinson's disease) the diagnosis can only be made on clinical grounds, clinical observation is of particular importance in distinguishing between organic and psychogenic movement disorders (Factor et al., 1995; Marsden, 1995). Williams et al. (Williams et al., 1995) suggest that the psychogenic origin of a movement disorder is proven only if the recovery of this movement disorder is achieved through psychotherapy or if this movement disorder changes in its course, the picture of its manifestation is not comparable with a picture of the manifestation of known organic movement disorders and in addition to this there are signs of the presence of some kind of mental disorder (cf. table. 25.1.1).
Table 25.1.1. Clinical characteristics of psychogenic movement disorders
Sudden onset as a result of a uniquely identifiable event.
Simultaneous occurrence of several movement disorders.
The symptoms of a movement disorder vary and fluctuate even within a single examination session.
Signs of a movement disorder do not correspond to the symptom complexes that are known for organically caused movement disorders.
Movement disorders are exacerbated when the examiner focuses on the affected part of the body.
Movement disorders improve or disappear when they are not the center of attention or when the patient performs tasks that require him to concentrate.
Especially expressed reaction of fear.
The severity of the movement disorder can be influenced by suggestion or placebo treatment.
- Patients' "neurological fallout" is inconsistent with neurological fallout in known neurological disease.
Patients also have psychiatric disorders.
There is no movement disorder when the patient is unaware that he is being monitored.
Movement disorder can be successfully treated with psychotherapy.
If there are several of the above characteristics, then this speaks in favor of a psychogenic movement disorder. This table is given in a modified form by Williams, Ford and Fahn (Williams, Ford & Fahn, 1995).
We also distinguish a third class of movement disorders, namely disorders resulting from inadequate compensation (Mai, 1996). What is meant by this can be explained by the example of the occurrence of writing spasm. Limitation of hand function, initially organically determined (eg, inflammation of the tendon sheath, reduced tactile sensitivity in the fingers), leads to the fact that the movements when writing become less free and handwriting may become less legible. The patient reacts to this by starting to hold the pencil differently, changing the position of the hand and the whole arm. For a short time, this achieves greater legibility of handwriting. However, after a longer time, the learned motor program, which until now was included in writing, is replaced by new and most often extremely non-ergonomic movements. Writing requires more and more effort and may eventually become completely impossible. If these learned misconceptions are corrected, a marked improvement in writing function can often be achieved (Mai & Marquardt, 1994).
Inadequate compensation occurs in the framework of many primarily organically caused movement disorders and can turn an initially mild limitation of function into a pronounced one. In addition, manifestations of inadequate compensation may continue even after the organic disease has already passed. Because they can be treated even if the underlying organic disease is unlikely to be curable (e.g., writing impairment in patients with multiple sclerosis, cf. Schenk et al., in press), it makes sense to delimit the aspects of movement disorders that are reducible to inadequate compensation, from organic disorders. In contrast to psychogenic disorders, in movement disorders due to inadequate compensation, correction of “non-ergonomic” postures and movements is required through an appropriate training program; psychotherapy is of little help here (Mai & Marquardt, 1995). In addition, inadequate compensation leads to movement disorders, the manifestation pattern of which is characterized by a high temporal density; inadequate compensation, as a rule, is not accompanied by mental disorders.
I. PROPULSION SYSTEMS
Successful treatment of movement disorders is impossible without an understanding of the anatomy and physiology of movement control systems. Meanwhile, knowledge in this area is clearly not enough, although it is gradually accumulating.
A. Pyramid system originates mainly in the posterior frontal lobes (mainly in the precentral gyrus), but also in the motor areas of the parietal lobes and other parts of the motor cortex. Cortical motor neurons are located here, the axons of which pass through the posterior knee of the internal capsule, the brain stem and pyramids, pass to the opposite side at the level of the medulla oblongata, form a contralateral corticospinal tract in the spinal cord and approach the spinal motor neurons. An important component of this system is the additional motor cortex, in which impulses are generated that precede movement. At the level of the spinal cord, there are local feedback mechanisms that regulate the activity of alpha motor neurons (gamma loop and other types of afferentation, including those received by neighboring segments).
B. Fibers of the parapyramidal system partly start from the same motor areas of the cortex as the pyramidal. They switch to spinal motor neurons via polysynaptic pathways passing through the red nucleus (rubrospinal pathway) and the reticular formation of the pons and medulla oblongata (reticulospinal pathway). The third component of the parapyramidal system - the vestibulospinal path - starts from the vestibular nucleus of Deiters, which receives afferent from the vestibular apparatus, the reticular formation and the cerebellum. The mediators of all these pathways are unknown.
B. Extrapyramidal system. All movements are carried out through the pyramidal and parapyramidal pathways. As for the extrapyramidal system, the main structures of which are the basal nuclei, its function is to correct and refine movements. This is achieved mainly due to influences on the motor zones of the hemispheres through the thalamus (see section IV).
D. Correction of movements also provides the cerebellum, mainly through influences on the vestibulospinal pathway, and also (with switching in the nuclei of the thalamus) on the same motor areas of the cortex as the basal nuclei (see section III).
II. DEFEAT OF THE PYRAMID AND PARAPYRAMID SYSTEMS
The main manifestations are paralysis and spasticity.
A. Paralysis may be complete (plegia) or partial (paresis), sometimes it is manifested only by the awkwardness of the hand or foot. Medical therapy is ineffective. Exercise therapy and massage are useful, training an intact neuromuscular apparatus and preventing contractures.
B. Spasticity characterized by an increase in the tone of the limb according to the "jackknife" type, increased tendon reflexes, clonus and pathological extensor reflexes (for example, the Babinski reflex). It can also be manifested only by the awkwardness of movements. Frequent symptoms also include spasms of the flexor muscles, which occur as a reflex to constant uninhibited impulses from skin receptors.
B. Treatment of spasticity
1. Essential medicines- benzodiazepines, baclofen, dantrolene (see table 15.1). The mechanism of action of each of them is not precisely established.
a. Benzodiazepines probably act at the spinal level, enhancing the postsynaptic effects of GABA and thereby promoting presynaptic inhibition. Another point of their application is the brain stem. The benzodiazepine receptors are located next to the GABA receptors. The most commonly used is diazepam.
b. Baclofen, a GABA agonist, has an inhibitory effect, apparently affecting bicuculline-insensitive GABA receptors. In addition, it reduces the impulse from gamma motor neurons and thus the degree of stretching of the muscle spindles.
in. Diazepam and baclofen reduce spasticity associated with afferent stimulation, but are not able to block pyramidal and parapyramidal influences, since the latter are likely to be realized through the excitatory mediators aspartate and glutamate or through the inhibitory mediator glycine.
d. Dantrolene prevents the release of calcium from the sarcoplasmic reticulum of muscle fibers and thereby disconnects the electromechanical coupling. This means that it reduces spasticity by increasing muscle weakness.
2. Doses. Since the mechanisms of action of benzodiazepines, baclofen and dantrolene are different, they can be combined. This allows you to reduce doses and avoid side effects. In motor neuron disease and stroke, these drugs appear to be ineffective. They are tested in diseases of the spinal cord, multiple sclerosis, cerebral palsy.
a. Diazepam is used in relatively large doses: starting with 2 mg 3 times a day, and then the dose is gradually increased, depending on tolerance, up to 60 mg / day and above. The main side effects are weakness, drowsiness, dizziness. With prolonged use, paradoxical insomnia, anxiety and aggressiveness are possible, often forcing the drug to be abandoned. Diazepam is contraindicated in angle-closure glaucoma. During treatment limit the use of alcohol. Transient liver dysfunction and blood changes are possible. Particular caution is necessary when starting treatment with diazepam and when it is canceled in patients taking anticoagulants. After a few years, diazepam may be replaced by other benzodiazepines.
b. Baclofen is indicated primarily for painful flexion spasms. The initial dose is 5 mg 2 times a day, then it is increased every 3 days to 80-120 mg / day. The drug is excreted mainly through the kidneys. Recently, intrathecal baclofen 50–100 mcg with an implanted pump and (in a limited number of studies) epidural administration have been shown to be effective. The main side effects are weakness, drowsiness, dizziness, gastrointestinal disorders, tremor, insomnia, headache, arterial hypotension. More dangerous are personality changes and hallucinations. Possibly impaired liver function. Cancellation of the drug should be gradual. Relative contraindication - epilepsy. During treatment limit the use of alcohol. With excessive intrathecal administration of the drug, CSF drainage is resorted to.
in. Dantrolene reduces spasticity by increasing muscle weakness. Therefore, although it is often more effective than other agents in spasticity, it is mainly used in patients with plegia who have lost the ability to move independently. The initial dose is 25 mg / day, if tolerated, it is increased within 4 weeks to 400 mg / day. Side effects - drowsiness, dizziness, nausea (usually transient), diarrhea, decreased GFR. A serious danger, especially in the elderly at a dose of more than 200 mg / day, is a hepatotoxic effect, therefore, during the treatment period, liver function should be monitored regularly. Elimination of dantrolene by 50% is carried out due to hepatic metabolism, in this regard, it is contraindicated in liver diseases. Caution should also be observed in severe heart or lung diseases.
d. Other drugs are used when benzodiazepines, baclofen, and dantrolene fail.
1) Tizanidine (alpha2-adrenergic stimulant) is used at a dose of up to 36 mg / day. According to antispastic action, it is approximately equivalent to baclofen. Side effects - muscle weakness, arterial hypotension, drowsiness, dry mouth. Long-acting tablets can be taken once a day. The drug is not manufactured in the USA.
2) Clonidine orally or cutaneously is sometimes effective.
3) A combination of phenytoin (300 mg/day) and chlorpromazine (300 mg/day) is used.
4) New anticonvulsant drug vigabatrin, according to some reports, is not inferior in effectiveness to baclofen.
3. Other treatments
a. When choosing a treatment, it should be remembered that sometimes spasticity allows you to maintain an upright position, and due to this makes it possible to walk (with the use of special splints).
b. Intrathecal administration of ethanol or phenol can reduce painful spasms in the legs. However, this procedure can cause urinary and fecal incontinence, so it is contraindicated in the presence of intact pelvic organ function. Botulinum toxin A is indicated when movements are impaired due to spasticity rather than paresis (see section IV.3.1.b). Sometimes its use facilitates patient care. It is used for cerebral palsy, multiple sclerosis (especially with adductor muscle spasms), strokes.
in. Blockade of peripheral nerves is indicated in severe cases. First, it is carried out with a local anesthetic. If spasticity decreases, a permanent blockade is performed with the introduction of ethanol or a 5% phenol solution.
d. Selective posterior rhizotomy is commonly used for cerebral palsy. Sometimes extensive rhizotomy is shown.
E. Exercise therapy, massage, etc. are extremely important. With the help of such methods, contractures can be prevented, which is especially important when there is hope for the restoration of function. Postural correction methods, local cooling, special tight clothing and range of motion exercises are used. It is important to minimize pain from the muscles, joints and internal organs.
e. Transcutaneous electrical nerve stimulation is sometimes effective.
and. Specialized centers use electrical stimulation of the cerebellum, posterior columns of the spinal cord, and other forms of electrical stimulation of the brain, but their effectiveness has not been proven.
h. Sometimes orthopedic treatment is helpful.
III. LESIONS OF THE CEREbellum
A. General information. The anatomy and physiology of the cerebellum has been well studied due to its relatively simple structure. Impulses enter the cerebellum from all levels of the central nervous system. Of particular importance is afferentation from the vestibular apparatus, spinal cord, and motor cortex. Efferent impulses go from the cerebellum to the pyramidal system (through the ventrolateral and anterior ventral nuclei of the thalamus) and to the stem nuclei of the parapyramidal system (primarily to the vestibular nucleus of Deiters). The lateral sections of the cerebellum are responsible for coordinating the movements of the limbs, the median sections are responsible for postures, gaits, and body movements. Damage to the cerebellum or its connections is manifested by intentional tremor, dysmetria, adiadochokinesis, and decreased muscle tone. It is possible that the cerebellum also plays some role in autonomic regulation, perception, emotions, and cognitive processes. The mediators of the efferent systems of the cerebellum are still unknown, and therefore drug therapy for cerebellar disorders is ineffective even in cases where the cause of these disorders has been clarified.
B. Treatment
1. Treatment primarily depends on the etiology (if it can be established).
2. The basis of therapy is exercise therapy. Some effect can be achieved with coordination exercises, rhythmic isometric contractions, stability and walking training with tight elastic suits and the use of assistive devices for movement. Intentional tremors can be reduced by using weights on the limbs weighing several hundred grams.
3. With scoliosis surgical treatment may be required.
4. Destruction of the ventrolateral parts of the thalamus(the area in which fibers switch from the cerebellum to the motor cortex) reduces cerebellar intentional tremor and the so-called rubral (or cerebellar efferent) tremor, which combines the features of parkinsonian and cerebellar tremor and is believed to occur when the efferent systems of the cerebellum are damaged.
5. Drug therapy
a. Physostigmine at a dose of up to 8 mg / day (in one tablet - 1 mg) is sometimes effective in hereditary cerebellar ataxia.
b. Oxytriptan (10 mg/kg/day) may reduce dysarthria and astasia.
in. Cerebellar disorders may be accompanied by other movement disorders that require special treatment.
IV. BASAL NUCLEI LESIONS
A. General information
1. Based on the anatomical structure of the basal nuclei, it can be concluded that closed circular connections play an important role in their function. The impulse from the cortex goes directly or through the central median nucleus of the thalamus to the small neurons of the striatum (caudate nucleus and putamen). Efferent fibers from the large neurons of the striatum, successively switching in the globus pallidus and the anterior ventral or ventrolateral nuclei of the thalamus, go to the ipsilateral motor cortex and affect the movements of the contralateral half of the body. The mediators mediating these associations are not exactly known, but GABA, acetylcholine, and glutamate are thought to play an important role.
2. The function of the cholinergic and glutamatergic systems of the basal ganglia is influenced by other circular neural circuits. The nigrostriatal system is of paramount importance. Its neurons form inhibitory dopaminergic synapses on the dendrites of small (presumably cholinergic) striatal neurons. The efferent systems that form synapses on the bodies of dopaminergic neurons in the compact part of the substantia nigra have been little studied; only fibers coming from the neurons of the globus pallidus and striatum and containing GABA or substance P as mediators were found. It is believed that there is also a strionigral cholinergic pathway. In addition, peptides such as somatostatin, leucine and methionine enkephalins, neurotensin, cholecystokinin, thyroliberin, vasoactive intestinal peptide, and angiotensin can influence the activity of striatal neurons. There are reciprocal connections of the striatum with the subthalamic nucleus, the prerubral nucleus, and midbrain neurons (some of these connections are serotonergic). From this scheme, it is clear that drugs that act on the cholinergic and dopaminergic systems are effective in lesions of the basal ganglia, although it is not clear why their action is antagonistic.
3. Treatment of extrapyramidal disorders is based on an understanding of the features of the synthesis and breakdown of dopamine. Recent advances in this area are associated with the identification of the neurotoxic effect of MPTP and the possibility of selective protection against the action of this and some other neurotoxins (for example, 6-hydroxydopamine) using MAO B inhibitors. Dopamine released in the synapses of the striatum acts on at least two types of receptors - D1 and D2. Activation of D1 receptors (but not D2 receptors) stimulates the formation of AMP. D2 receptors located on striatal neurons and on the ends of corticostriatal fibers can probably be in a high and low affinity state.
4. Movement disorders that occur when the basal nuclei are affected (extrapyramidal disorders) can be divided into hypokinesia (decrease in the volume and speed of movements; an example is Parkinson's disease or parkinsonism of another origin) and hyperkinesis (excessive involuntary movements; an example is Huntington's disease). Hyperkinesis also includes tics.
B. Drug-induced extrapyramidal disorders
1. Drugs that cause extrapyramidal disorders.
a. Medicinal extrapyramidal disorders have become common with the introduction of neuroleptics into practice. The action of phenothiazines, as well as butyrophenones and a number of other new neuroleptics (see Table 15.2), is due mainly to the blockade of dopamine D3 receptors in the limbic system.
b. Similar drugs (eg, prochlorperazine and metoclopramide) are used as antiemetics.
in. Sympatholytics that deplete neuronal mediators (tetrabenazine, reserpine) and catecholamine analogs (false mediators) such as methyldopa also cause extrapyramidal disorders.
d. With prolonged therapy with levodopa, hyperkinesis may occur (see section IV.B.4.a.5.a).
2. Regression of drug-induced extrapyramidal disorders possible with the abolition or reduction of the dose of the drug.
3. Types of drug-induced extrapyramidal disorders
a. Acute idiosyncratic hyperkinesis usually occurs during the first days of neuroleptic treatment. They can be manifested by rapid short-term involuntary movements (chorea, athetosis, ballism; see item IV.B.3.d) or dystonia, which can develop after the first dose of an antipsychotic. It is characterized by long, slow twisting movements of the neck and torso, limbs (especially proximal parts) and similar eye movements (oculogyric crises). Respiratory muscles may be involved. Acute dystonia is treated with parenteral anticholinergics (benzatropine 1 mgv/miliv/v) or diphenhydramine (50 mg iv). Subsequently, these drugs are usually taken orally within 48 hours. At the same time, there are cases of paradoxical dystonia when H1-blockers are taken orally. The drug that caused dystonia is canceled.
b. Drug-induced parkinsonism is manifested by dose-dependent hypokinesia, increased muscle tone and tremor (frequency 3-5 s–1), usually occurring within a few days to 1 month after the start of the antipsychotic. These disorders may persist for many months after discontinuation of the drug. Treatment:
1) Reducing the dose of the drug, or
2) Addition of M-anticholinergic:
a) Benzatropine (0.5-4 mg 2 times a day).
b) Biperiden (1-2 mg 3 times a day).
c) Trihexyphenidyl (1-5 mg 3 times a day).
Benzatropine is eliminated quickly, trihexyphenidyl - slowly, biperiden occupies an intermediate position. M-anticholinergics can reduce the antipsychotic effect of neuroleptics. They are not prescribed to everyone, and usually no longer than 2-3 months. Prophylactically, in the treatment of neuroleptics, M-anticholinergics are not prescribed. From a theoretical point of view, levodopa and dopamine agonists should be effective, but when taken with antipsychotics, they almost always cause stupor.
in. Akathisia (motor restlessness, extreme anxiety, pathological restlessness) is a dose-dependent side effect of neuroleptics that occurs in the first days of treatment in almost 20% of patients. The pathogenesis of akathisia is unclear. Treatment - the abolition of neuroleptics. For the prevention of akathisia, antipsychotics are started with minimal doses. It is important not to confuse this complication with psychotic manifestations, so as not to prescribe an antipsychotic in ever-increasing doses. Anticholinergics are ineffective. There is evidence of the effectiveness of benzodiazepines, alpha-blockers, clonidine and amantadine. In rare cases, akathisia occurs as a late complication that is less treatable.
G. Late neuroleptic hyperkinesis ("tardive dyskinesia")
1) General information. Late neuroleptic hyperkinesias usually occur no earlier than a year of constant use of antipsychotics. They are observed in almost 20% of patients taking antipsychotics, and in the elderly, especially in women, they are even more common. The likelihood of their development is higher in patients with acute reactions at the beginning of treatment, as well as in the presence of primary affective disorders. Late neuroleptic hyperkinesis can be manifested by choreic movements in the face and limbs, athetosis, dystonia or akathisia. Often, hyperkinesis is limited only to the muscles of the head and neck or mouth (chewing, smacking, sticking out the tongue, etc.). Sometimes the respiratory muscles are involved.
2) Treatment is aimed at enhancing cholinergic effects or at reducing dopaminergic ones. Means acting on the GABAergic strionigral pathways are also used. Additional blockade of dopamine receptors by increasing the dose of antipsychotic can temporarily reduce the severity of late neuroleptic hyperkinesis, but as a result, the dose of neuroleptic still has to be reduced. To avoid this complication, the dose of antipsychotics should be minimal. Anticholinergics should be used with caution in tardive neuroleptic hyperkinesias, as they may exacerbate them, although they probably do not increase their risk.
Late neuroleptic hyperkinesis can proceed in waves and disappear only months or years after the withdrawal of the antipsychotic. In half of the patients, hyperkinesis regresses within 5 years, but sometimes remains forever. Fortunately, in most patients, hyperkinesis, having reached a certain level, does not increase in the future. Treatment of late neuroleptic hyperkinesis is difficult; many drugs have been tried. The effectiveness of interruptions in antipsychotic treatment has not been proven, at the same time, such interruptions can be dangerous.
a) Tetrabenazine depletes the reserves of biogenic monoamines in the CNS. Start with 12.5 mg, then gradually increase the dose (maximum dose - 200 mg / day). Side effects - parkinsonism, drowsiness and depression; more rare - anxiety, asthma attacks, insomnia, akathisia. When using tetrabenazine, MAO inhibitors are contraindicated. The drug is not yet approved by the FDA.
3) Reserpine, like tetrabenazine, depletes the reserves of biogenic monoamines in the central nervous system. Start with 0.25 mg / day orally, then gradually increase the dose to 2-4 mg / day. The main side effect is orthostatic hypotension, which usually resolves within 1-2 weeks, but at the beginning of treatment it is recommended to measure blood pressure regularly and avoid standing up abruptly.
4) Baclofen, valproic acid, diazepam, alpha-blockers, amantadine, clonidine, and levodopa/carbidof have been used with varying success.
B. Parkinson's disease
1. General information. Parkinson's disease is a movement disorder of unknown origin, which is based on the primary lesion of pigment-containing dopaminergic neurons in the dense part of the substantia nigra and other pigment-containing nuclei of the trunk. In these sections, neuronal death, gliosis, and Lewy bodies are found in the cytoplasm of preserved neurons. Studies of parkinsonism caused by neurotoxins point to the role of free radicals in the pathogenesis of the disease. The existence of familial cases of the disease indicates a genetic predisposition, which may be expressed in a special sensitivity to neurotoxins. The risk of disease for close relatives of the patient is increased by about 10 times.
2. Clinical picture. The disease is manifested by slowly progressive hypokinesia, increased muscle tone and resting tremor. Typical external signs are poor facial expressions, rare blinking, quiet monotonous speech, slow movements, difficulty in walking and turning in bed. Violation of fine finger movements leads to micrography. Posture becomes hunched, gait - shuffling, hands do not participate in walking. Some patients have difficulty maintaining balance when walking, which causes the gait to mince. Muscle tone is changed in the type of waxy rigidity or "cogwheel". Often already at an early stage, a coarse asymmetric resting tremor (with a frequency of 3-7 s–1) is noticeable, reminiscent of “pill rolling”. With complete relaxation, the tremor usually disappears. Sometimes there is also a symmetrical postural tremor with a frequency of 2-12 s–1. The most convenient classification of the severity of Parkinson's disease proposed by Hen and Yar (see Table 15.3).
In one study, dementia was found in almost 30% of patients treated for more than 6 years; at the same time, her diagnosis in the advanced stage of Parkinson's disease is difficult due to communication difficulties. Meanwhile, even with mild dementia, drugs are more likely to cause side effects, such as delirium. Progressive disturbances in balance and respiratory rhythm, short-term episodes of "freezing" also lead to disability; all of these manifestations are usually resistant to treatment. Prior to the introduction of levodopa, 70% of patients died within 7 years.
3. Diagnosis and differential diagnosis. Parkinson's disease is differentiated from other diseases accompanied by parkinsonism - a syndrome of extrapyramidal disorders, including hypokinesia, increased muscle tone and rest tremor. Diagnosis is usually uncomplicated when a 50- to 60-year-old person slowly develops typical symptoms. It is difficult to confirm the atherosclerotic or syphilitic nature of parkinsonism. An extremely rare cause is brain tumors. Causes other than non-obstructive hydrocephalus and Creutzfeldt-Jakob disease are usually easy to identify (traumatic brain injury, drug use, carbon monoxide, cyanide, manganese poisoning). Oculogiric crises are characteristic of postencephalitic and drug-induced parkinsonism. Parkinsonism is one of the complications of Economo's epidemic lethargic encephalitis, which was widespread during and after the First World War. The significance of vascular diseases in the origin of Parkinson's disease is debatable, although brain vascular lesions can certainly lead to parkinsonism. Degenerative diseases of the brain, in which parkinsonism is combined with other syndromes, are given in Table. 15.4. It is not uncommon for these diseases to be recognized after a course of levodopa treatment fails, although Lewy body disease may initially respond well.
4. The task of treatment in Parkinson's disease is to maintain a balance between the dopaminergic and cholinergic systems (see section IV.A), that is, either increase the content of dopamine or its agonists in the striatum, or reduce the activity of cholinergic systems. Means for correcting neuropeptide deficiency do not yet exist. The choice of treatment depends on the age and severity of the condition. At an early stage, sometimes it is better to limit yourself to observation. The drug of choice in most cases is levodopa, but in young people, you can start with selegiline, bromocriptine, or M-anticholinergics.
a. Levodopa turns into dopamine - a stimulator of D1 and D2 receptors. At the beginning of treatment, desensitization of D2 receptors may be observed. The main indication is disabling hypokinesia. To reduce side effects such as nausea, vomiting, cardiac arrhythmias, and orthostatic hypotension, levodopa is used in combination with peripherally acting DALA inhibitors; before the introduction of the latter into practice, side effects often prevented a rapid increase in the dose of levodopa and a good effect. Some researchers believe that levodopa should be avoided as long as possible, but most doctors prescribe it as soon as the disease begins to interfere with a fulfilling life.
1) The most commonly used combination preparations are levodopa/carbidopa (see Table 15.6). Carbidopa inhibits DALA (see Fig. 15.2) in peripheral nerve endings, thereby increasing the amount of levodopa in the CNS. Treatment is usually started with tablets containing 25 mg carbidopa and 100 mg levodopa, 3 times a day (but not with tablets of 10 mg carbidopa and 100 mg levodopa, since 30 mg carbidopa per day is not enough). To prevent nausea, tablets are taken immediately after meals. If tolerated, the daily dose is increased by 1 tablet every 3-4 days for 4 weeks. The final dose, based on levodopa, should not exceed 1 g / day. If this dose is insufficient, dopamine receptor stimulants are added. The effect usually appears within 2 weeks from the start of treatment. A prolonged drug is available, but until the onset of akinetic paroxysms (see IV.B.4.a.6), the need for it usually does not arise.
2) Benserazide/levodopa is prescribed in the same way. The higher content of the DALA inhibitor (50 mg of benserazide instead of 25 mg of carbidopa) improves the tolerability of the drug (in particular, it causes less nausea). There is a prolonged drug.
3) In some countries, carbidopa and benserazide are available as separate preparations, which allows you to individually select the ratio of levodopa and DALA inhibitor.
4) Response to treatment. A significant improvement is noted in about 80% of patients, but it is impossible to predict the effect of therapy in advance. Long-term observations show that after 2-3 years, the effectiveness decreases and after 5-6 years, only 25-50% of patients have the same effect as at the beginning of treatment. Long-term therapy with levodopa reduces mortality, but with increasing life expectancy, dementia often comes to the fore. According to some reports, approximately 20% of patients have depression before the start of treatment. With successful therapy with levodopa and an increase in motor abilities, latent depression sometimes becomes apparent and leads to suicidal attempts. For depression, tricyclic antidepressants are added (non-selective MAO inhibitors are contraindicated).
5) Dose-dependent side effects. Changes in motor activity associated with fluctuations in the serum concentration of levodopa are not as noticeable at an early stage of treatment as one would expect, based on its rapid elimination. Apparently, this is due to the accumulation and slow release of the mediator by dopaminergic neurons. With prolonged treatment, such differences become pronounced. Long-acting levodopa preparations have been developed to reduce them, but their effectiveness turned out to be average. Since the effect of the prolonged drug comes slowly when taken in the morning, you can add a regular drug to it. Another approach to correct these effects is to prescribe a low-protein diet, which reduces competition for transport systems between levodopa, phenylalanine and tyrosine, primarily at the level of the blood-brain barrier. The protein content in the diet is reduced to 0.8 g/kg, while protein products can be consumed at regular intervals during the day or mainly in the evening. In the elderly, the daily intake of protein is often quite small even without special diets.
a) Hyperkinesis at the height of the serum concentration of levodopa may occur by the end of the first year of treatment when using large doses. Over time, hyperkinesias become more severe, generalized, and after 6 years of treatment are observed in almost 75% of patients. Such hyperkinesis occurs 20-90 minutes after taking levodopa and clinically resembles late neuroleptic hyperkinesis associated with the use of antipsychotics. They usually present with chorea, although dystonia, ballismus, and myoclonus are also possible. Hyperkinesias usually disappear within a few days with a gradual decrease in the dose; at the same time, other, less unpleasant side effects also decrease: dry mouth, blurred vision, orthostatic hypotension. Vitamin B6 reduces the effect of levodopa unless a DALA inhibitor is used simultaneously, so vitamin B6 (and multivitamin preparations containing it) are prescribed only if the patient is receiving carbidof or benserazide.
b) Effect depletion syndrome (hypokinesia occurring on the decline in serum concentration) also becomes more pronounced with prolonged treatment. When it appears, they usually switch to a more frequent intake of smaller doses.
c) Two-phase reaction. Sometimes short-term hyperkinesias occur shortly after taking the first morning dose, then they disappear, and after 1-2 hours severe dystonic spasms develop, mainly in the legs. These spasms often decrease after taking another dose of levodopa. Baclofen (5-40 mg/day) can be used to treat these conditions. In the future, akinetic paroxysms often appear.
d) The most unpleasant nausea and vomiting, which sometimes occur, even if the drug is taken in a minimal dose during or after a meal. In this case, you can use light antiemetics: trimethobenzamide (25 mg 3 times a day), domperidone (10-20 mg 30 minutes before taking levodopa), as well as M-anticholinergics and H1 blockers.
e) Vivid frightening dreams usually become less pronounced if the drug is not taken at night.
f) Anxiety, agitation, delirium, delirium, visual hallucinations and extended psychotic reactions usually regress within a day after dose reduction, but occasionally they persist for several weeks. Euphoria, mania and hypersexuality are also possible.
g) Other side effects - hot flashes, orthostatic hypotension, ventricular extrasystoles. With orthostatic hypotension, an elevated position of the head during sleep, bandaging of the legs, taking fludrocortisone (0.1-0.2 mg / day) are shown. Rarely, arterial hypertension occurs. Mild transient liver dysfunction and blood changes are possible. Rapid discontinuation of levodopa should be avoided, in which disorders resembling neuroleptic malignant syndrome (hyperthermia, muscle rigidity, coma) may occur.
6) Dose independent side effects
a) Akinetic paroxysms ("on-off syndrome") are more often observed with long-term treatment (with continuous use for more than 5 years - in about 50% of patients). They are manifested by sudden unpredictable attacks of severe akinesia and a drop in muscle tone, accompanied by a feeling of fear. The attack lasts from 30 minutes to several hours and ends as suddenly as it begins. Additional reception of levodopa is ineffective. The mechanism is unclear. According to some reports, during an attack, as in the exhaustion syndrome, a low level of levodopa in serum is detected; however, maintaining a constant serum level of levodopa by intravenous administration does not always prevent akinetic seizures. Recently, it has been suggested that levodopa itself may inhibit locomotor activity. At the same time, it remains unclear whether akinetic paroxysms are due to this inhibitory effect of levodopa, or whether they are associated with the accumulation of functionally active dopamine metabolites, a decrease in the deposition capacity of dopaminergic neurons, or fluctuations in receptor affinity. More frequent use of levodopa (every 2 hours) smoothes out these side effects; to do this, a levodopa/carbidopa tablet can be cut into four parts with a blade. There is evidence of the effectiveness of levodopa methyl ester, but so far it is being tested. To prevent akinetic paroxysms, they tried to take breaks in taking levodopa for up to 1 week, but they turned out to be ineffective. The initial treatment regimen with levodopa does not appear to affect the likelihood of developing akinetic paroxysms and effect wasting syndrome, but may play a role in the development of hyperkinesia at the height of serum concentration.
b) The main treatment for akinetic paroxysms is apomorphine s.c. A few days before the first administration of the drug, domperidone is prescribed to prevent vomiting. Usually start with 1.5 mg of apomorphine, then gradually increase the dose until the effect is achieved or up to 4.5 mg. The effect occurs within 10 minutes and lasts up to 50 minutes. The drug reduces the duration of paroxysms, but does not affect their frequency. There are sublingual forms of apomorphine.
7) Contraindications to levodopa are relatively few. They include angle-closure glaucoma (most cases of glaucoma are open-angle glaucoma), a history of melanoma (recently, the validity of this contraindication has been disputed), the need for the use of MAO inhibitors. Particular care is needed for cardiac arrhythmias, recent myocardial infarction and for upcoming surgery.
b. dopamine agonists
1) Bromocriptine is a dopamine receptor stimulant that acts primarily on D2 receptors. With fluctuations in motor activity, its appointment allows you to reduce the dose of levodopa by 30%. Bromocriptine acts on postsynaptic receptors and modulates L-DOPA-dependent dopamine binding to presynaptic receptors. Trials have shown that the efficacy of bromocriptine as an initial therapy is lower than that of levodopa. Theoretically, the combination of the postsynaptic action of bromocriptine and the presynaptic action of levodopa should result in an enhanced effect. The initial dose of bromocriptine is 2.5 mg / day, then it is slowly increased over several weeks. The effect develops slowly, so it is recommended to maintain a relatively low dose (for example, 12 mg / day) for a long time (for several months) before judging its effectiveness. The maximum dose is 30-50 mg / day, usually in 2-3 doses. A significant part of the drug is metabolized during the first passage through the liver. Larger doses give more pronounced side effects. Early side effects are the same as levodopa, but less so; these include nausea (it can be reduced with domperidone), vomiting, orthostatic hypotension. At the same time, with long-term therapy, more dangerous complications are possible - first of all, acute clouding of consciousness with visual hallucinations, which can persist for several weeks after discontinuation of the drug. Other mental side effects are the same as when taking large doses of levodopa. Swelling of the lower leg and erythromelalgia quickly disappear after discontinuation of bromocriptine. Pleuropulmonary fibrosis (pleural thickening, lung infiltrates, and pleural effusion) is rare.
2) There are analogues of ergot alkaloids that are not inferior in effectiveness to bromocriptine. Pergolide, a D1 and D2 receptor stimulant, is being extensively tested. The average effective dose is 2-4 mg / day, but treatment is usually started with 0.1 mg / day. According to some reports, when taking pergolide and other dopamine receptor stimulants, akinetic paroxysms are less pronounced, but there is no reliable data on their long-term use. Pergolide is more likely to cause cardiac arrhythmias. It is advisable to combine this drug with low doses of levodopa. Contraindication to the appointment of pergolide, as well as other ergot alkaloids - an allergy to them. The side effects of pergolide are the same as those of bromocriptine.
in. Combination therapy is now commonly used - start with levodopa drugs (eg, levodopa/carbidopa, 100/25 mg 3 times a day for 3 months), then add small doses of dopamine agonists (eg, bromocriptine, 2.5 mg/day, then for 3 months a dose of increase to 2.5 mg 3 times a day). Combination therapy is carried out to reduce side effects (primarily changes in motor activity) and increase life expectancy.
M-anticholinergics shown in the initial stage, if the patient is most concerned about tremor. However, as fixed assets they are used less and less.
1) The most commonly used drugs are:
a) Prophenamine, 10-20 mg 3 times a day.
b) Benzatropine, 0.5-4 mg 2 times a day.
c) Biperiden, 1-2 mg 3 times a day.
d) Trihexyphenidyl, 1-5 mg 3 times a day.
2) The maximum dose depends on the severity of side effects. The dose is increased gradually to the maximum tolerated. In particular, it is possible to increase the dose of prophenamine up to 400 mg / day.
3) Side effects. Dry mouth, disturbance of accommodation, dizziness are common but usually well tolerated. More serious are acute confusion, constipation, urinary retention, and exacerbation of glaucoma. Possible intellectual impairment; when the dose is reduced, they disappear, but sometimes - only after a few weeks. Abrupt cancellation of M-anticholinergics can lead to an exacerbation of the disease. With mental disorders that occur during treatment, tranquilizers are not indicated. Mild laxatives help with constipation. Spasm of the bladder neck in men may require surgery. With glaucoma, M-anticholinergics can be used if it is being treated.
e. Amantadine and amphetamines have an antiparkinsonian effect by promoting the release of endogenous dopamine from nerve endings in the striatum.
1) Amantadine is initially prescribed at a dose of 100 mg / day orally, then it is gradually increased to 100 mg orally 3 times a day. The effect is usually short-lived, therefore intermittent use of the drug is recommended. Side effects - depression, heart failure, swelling of the legs, marbled skin, urinary retention, acute confusion, often with visual hallucinations. The drug is excreted unchanged in the urine. The effect of amantadine may also be associated with its anticholinergic effect.
2) Amphetamines have previously been used in oculogyric crises. Their use is hindered by side effects. Methylphenidate is used to relieve symptoms associated with impaired sensitivity, in particular tingling, numbness, crawling, burning pains, and headaches.
3) Apomorphine stimulates D1- and D2-receptors, and also promotes the release of dopamine. It is administered n / k with akinetic paroxysms (patients can enter it on their own); as an antiemetic, along with it, domperidone is prescribed at a dose of 10-80 mg / day (see paragraph IV.B.4.a.6.b). Apomorphine often causes hyperkinesis.
e. Selegiline - MAO B inhibitor and dopamine reuptake. It is used as an adjunct to levodopa. The drug has many other effects. In particular, it can protect neurons from the action of neurotoxins that cause free radical oxidation and thus, according to one of the theories, play an important role in the pathogenesis of Parkinson's disease. This effect of selegiline is due to the fact that it blocks the formation of neurotoxins (see Fig. 15.3) and induces superoxide dismutase and catalase, which contribute to the elimination of free radicals. A collaborative study was conducted on the combination of selegiline with vitamin E, which also neutralizes free radicals. Selegiline is initially prescribed at 5 mg in the morning and at night for 1 week, then 100 mcg / kg / day. The drug is taken with food. At a dose of 30 mg/day, selegiline inhibits not only MAO B, but also MAO A. In the process of metabolism, it turns into amphetamine, which may partially explain the appearance of euphoria. The role of selegiline in the treatment of Parkinson's disease has not been definitively determined. It can probably be considered as a means to reduce the dose of levodopa and prolong its action in the effect wasting syndrome. Selegiline should not be combined with pethidine, other MAO inhibitors and fluoxetine. Common side effects include hyperkinesis, nausea, dizziness, and confusion.
and. propranolol sometimes used to reduce postural tremor, often observed in Parkinson's disease (doses - see section V.B.3.c.1). It is also useful for pain not associated with dystonia.
h. Botulinum toxin A indicated for equinovarus and pincer dystonia, if other methods are ineffective (see section IV.3.1.b).
and. Surgery
1) Ventrolateral thalamotomy is used for severe unilateral tremor in the absence of the effect of drug therapy and in cases where disability is associated with motor, but not intellectual impairment. Bilateral thalamotomy leads to gross speech disorders. Pallidotomy is increasingly used for hypokinesia and tremor. Surgical treatment, according to some reports, reduces the likelihood of subsequent development of hyperkinesis associated with levodopa therapy.
2) Transplantation into the basal nuclei of catecholamine-containing tissues obtained from an adult or a fetus has led in several cases to a significant improvement. Collaborative tests of this method are being carried out. Adult adrenal medulla (with very limited effect) and fetal substantia nigra were used for transplantation. According to available data, the effect of surgery is usually difficult to predict, and most likely, this method will be used in a very limited number of patients.
k. Other methods of treatment. Direct evidence of the effectiveness of non-pharmacological treatments is insufficient (the exception is social assistance, which undoubtedly has a beneficial psychological effect). Nevertheless, a general rehabilitation program is appropriate for all elderly patients. Speech therapy methods are usually ineffective, but sometimes speech can be made more intelligible with the help of external stimuli, such as a metronome. Some are shown occupational therapy. The patient can be taught various kinds of techniques that facilitate the beginning of movements and walking.
5. Non-motor symptoms. In addition to movement disorders, Parkinson's disease is manifested by many other symptoms. The most common of them are presented in Table. 15.5.
6. Conscientiousness in fulfilling the doctor's prescriptions. If drug therapy is ineffective, it is advisable to hospitalize the patient and re-treat under strict supervision. Sometimes in such cases a degenerative disease of the brain is detected, accompanied by parkinsonism (see Table 15.4).
D. Huntington's disease
1. General information. Huntington's disease is an autosomal dominant disorder characterized by dementia and movement disorders. In cases where the disease begins in adulthood, it is characterized by symptoms of hyperactivity of the dopaminergic system. Chief among these symptoms is chorea (rapid, jerky movements, usually of the limbs, sometimes resembling voluntary movements). It is often accompanied by a decrease in muscle tone. In Huntington's disease and other extrapyramidal diseases, chorea is often combined with athetosis - slow and smooth worm-like movements that are less reminiscent of arbitrary. Since severe chorea is practically indistinguishable from athetosis, and the morphological substrate seems to be the same, they are sometimes considered as a single hyperkinesia (choreoathetosis). In childhood, Huntington's disease can manifest as parkinsonism. Dysarthria is often noted. There is a postural tremor. The main manifestations also include progressive emotional disorders, personality changes and dementia. Often there is depression; Approximately 5% of patients end their lives by suicide.
2. Differential diagnosis. There are no generally accepted methods for diagnosing Huntington's disease at the preclinical stage, although a genetic defect underlying the disease (repeating nucleotide sequence on the 4th chromosome) has been found. Similar hyperkinesis can occur with other diseases that affect the basal ganglia: mercury poisoning, rheumatism (Sydenham's chorea), infections (diphtheria, whooping cough, rubella, other viral encephalitis, etc.), taking oral contraceptives, anticonvulsants, lithium, antiemetics, with pregnancy (rarely), thyrotoxicosis, posthemiplegic athetosis, Lesch-Nyhan syndrome, bilirubin encephalopathy, senile chorea and other diseases. Treatment in all these cases is the same as for Huntington's disease.
3. Treatment(see table 15.6). At an early stage, drugs that deplete dopamine stores or block dopamine receptors are used.
a. Haloperidol, 1-4 mg 4 times a day. Possible side effects that are not related to the effect on D2 receptors (and, accordingly, on the motor systems): orthostatic hypotension, anticholinergic and sedative effects, neuroleptic malignant syndrome.
b. Chlorpromazine, 50 mg 3 times a day.
in. Tetrabenazine - see item IV.B.3.d.2.a.
g. Reserpine, 0.5 mg 4 times a day (used for Sydenham's chorea).
e. Propranolol in high doses is used to reduce postural tremor.
D. Degenerative diseases of the brain, accompanied by parkinsonism,- see table. 15.4. Treatment is symptomatic.
E. Diseases manifested by parkinsonism and choreoathetosis, are rare. Autopsy usually reveals extensive involvement of the basal ganglia. These diseases should always be considered in the differential diagnosis in patients with parkinsonism or choreoathetosis. Treatment is aimed at both the underlying disease and movement disorders. However, in parkinsonism due to lesions of the striatum, levodopa is usually ineffective, since the very substrate of dopamine action is damaged.
1. Wilson's disease
a. General information. Wilson's disease is a rare autosomal recessive disease that manifests itself mainly between the ages of 10 and 40 and is characterized by progressive damage to the liver and nervous system, the formation of Kaiser-Fleischer corneal rings, and sometimes impaired renal function. Neurological disorders occur in two main forms. When started at a young age, there is a rapid progression with the development of athetosis, rigidity or dystonia; myoclonus is also possible. This form is more difficult to treat. If the disease begins in adulthood, then it usually proceeds more benignly, responds better to treatment and is manifested mainly by tremor (postural and intentional), dysarthria (spastic, ataxic or hypokinetic nature) and dysphagia. Asterixis (see item VI) usually accompanies progressive liver failure.
b. Diagnosis is by slit-lamp Kaiser-Fleischer rings, abnormal liver function, and changes in copper metabolism. An important sign is a reduced content of copper and ceruloplasmin in serum and an increased excretion of copper in the urine. CSF copper concentration and urinary copper excretion are good indicators of treatment success. Liver biopsy may reveal cirrhosis and elevated copper levels. To identify heterozygotes, radioactive copper is injected into / into, and then its excretion with feces is determined for several days. A liver biopsy is also performed: in heterozygotes, the copper content in the liver is moderately increased. CT scans of the brain can detect zones of reduced density in the basal ganglia, but its results do not predict the effectiveness of treatment.
in. Treatment
1) Penicillamine (250 mg 3 times a day between meals) in most cases slows the progression of the disease with a late onset, but taking the first doses can cause an exacerbation. The effect may appear several months after the start of treatment. Treatment continues for life. During pregnancy, the dose can be reduced. Withdrawal may result in death. Allergic reactions are observed in 30% of patients. Side effects (nausea and vomiting, ageusia, rash, adenopathy, arthralgia, leukopenia and thrombocytopenia) occur more often if the dose exceeds 2 g / day. When treated with drugs containing the D- and L-isomer, nephrotic syndrome and optic neuropathy are possible; the latter decreases under the influence of pyridoxine (100 mg/day). In acute allergic reactions, corticosteroids are indicated. Ageusia can be reduced with zinc sulfate. Recently, Goodpasture's syndrome has been described as a side effect. In animals, penicillamine is teratogenic.
2) A diet low in copper (less than 1.5 g/day) reduces the need for penicillamine. Foods high in copper include liver, mushrooms, chocolate, as well as shrimp, lobster, oysters, etc.
3) Some believe that zinc sulfate or acetate, which reduces copper absorption, may be the drug of choice and allow you to delay the appointment of penicillamine. Zinc preparations are harmless. They can be used in combination with penicillamine and if it is intolerant. The drugs are prescribed at 25 mg (in terms of pure zinc) every 4 hours between meals and at bedtime.
4) Trientine (400-800 mg 3 times a day before meals) is used for intolerance to penicillamine.
5) Tetrathiomolybdate is a promising new treatment for Wilson's disease. Unlike penicillamine, this drug does not cause an initial exacerbation.
6) Correction of metabolic acidosis improves neurological status in renal tubular acidosis.
7) Sometimes they resort to liver transplantation.
8) Symptomatic therapy of movement disorders is described in paragraph IV.G.3.
2. Calcification of the basal nuclei and the dentate nucleus
often detected in the elderly and may be one of the causes of mild motor disorders, often found in this age group. With severe calcification, there are severe progressive motor disorders in the form of parkinsonism or choreoathetosis.
a. The differential diagnosis is based on the data of the anamnesis, examination and biochemical studies (see Table 15.7).
b. Treatment. In the case of hypocalcemia (with postoperative or idiopathic hypoparathyroidism or with pseudohypoparathyroidism), the progression of movement disorders can be stopped if the calcium concentration in the blood is normalized with vitamin D (50,000-100,000 IU / day) and calcium supplements. To prevent an overdose of vitamin D, regular biochemical blood tests are necessary. Regression of movement disorders is rare, except perhaps in cases of idiopathic hypoparathyroidism. With striopallidodentate pseudocalcification (Fara's disease), biochemical blood parameters remain within the normal range; there is no treatment. Less commonly, calcification occurs with hyperparathyroidism and pseudopseudohypoparathyroidism (normocalcemic pseudohypoparathyroidism).
3. With Hallervorden-Spatz disease
iron-containing pigments are deposited in the pale ball and the reticular part of the black substance. The disease manifests itself in childhood with progressive parkinsonism or choreoathetosis, less often with other movement disorders. Iron chelating agents do not reduce pigment deposits. Treatment of movement disorders - see item IV.D.3.
4. Ataxia-telangiectasia
a rare hereditary disease manifested by immunodeficiency and various hyperkinesias. An important sign is violations of the horizontal gaze and conjunctival telangiectasias. The disease can also occur in adults, in which case it is not accompanied by immunodeficiency and is more variable. Equally rare is another disease, manifested mainly by hyperkinesis, the acanthocytosis-chorea complex.
5. Less often, parkinsonism or hyperkinesis occurs with infectious diseases
(encephalitis, AIDS, syphilis), immunological disorders (particularly in SLE), traumatic brain injury with subdural hematoma.
G. Hemiballismus(sharp throwing rotational movements) develops, as a rule, with damage to the subthalamic region, most often with hemorrhage. Even without treatment, symptoms in most cases improve significantly within a few weeks. With severe hyperkinesis in the acute stage, reserpine or tetrabenazine is usually prescribed first, followed by phenothiazines or haloperidol. The most effective treatment for severe chronic hemiballismus is ventrolateral thalamotomy.
Z. Idiopathic hyperkinesis form a single group of movement disorders, which for convenience is divided into generalized and segmental forms. Generalized forms are 10 times more common, their prevalence reaches 30:100,000. Typical generalized idiopathic hyperkinesis is torsion dystonia, this also includes secondary hyperkinesis associated with encephalitis, traumatic brain injury, poisoning (for example, manganese). Segmental disorders include spasmodic torticollis, writing spasm, Meige's facial spasm, and blepharospasm.
1. Treatment
a. Drug treatment of idiopathic hyperkinesis, both generalized and segmental, is usually ineffective. First of all, M-anticholinergics are used (especially high doses of prophenamine), and if they are ineffective, diazepam, haloperidol, tetrabenazine or lithium.
b. Botulinum toxin A blocks the release of acetylcholine from nerve endings, which leads to reversible muscle paresis. It is used for segmental hyperkinesis; treatment should be carried out by a doctor who is well acquainted with this method. With blepharospasm, spastic torticollis, facial hemispasm and spastic dysphonia, its effectiveness reaches 90%. With facial hemispasm, botulinum toxin is not injected into the zygomatic muscle, since its paresis causes excessive inconvenience. Botulinum toxin is also indicated for trismus, with severe spasticity, when it prevails over paresis (with traumatic brain injury, strokes, multiple sclerosis). In patients with apraxia of opening the eyes, as well as in professional convulsions, for example, with writing spasm, the effect is worse. Botulinum toxin is injected only into those muscles that are involved in hyperkinesis and in minimal doses in order to achieve a decrease in hyperkinesis, while maintaining muscle strength as much as possible; for this purpose, the introduction is carried out under the control of EMG. The effect may appear after a few days, and after about 3 months it usually disappears, and therefore repeated injections are necessary.
The activity of preparations of different production is not the same. The toxin used in the US is about 5 times more potent than the toxin produced in the UK. Doses range from 2 units (when injected into the small muscles of the hand and larynx) to 150 units (when injected into large muscles, such as the tibialis posterior). With blepharospasm, 20 units are usually administered. In case of inefficiency, re-introduction is carried out. Long-term inefficiency may be due to the formation of antibodies. In this case, botulinum toxin is indicated. Sometimes, after the introduction of botulinum toxin, the spasm does not go away, despite the development of muscle weakness. Relative contraindications: myasthenia gravis, treatment with aminoglycosides.
in. In some patients, a positive effect is observed when wearing tight tight clothing.
d. In some studies, an effect has been obtained with electrical stimulation of the spinal cord.
2. Certain types of idiopathic hyperkinesis
a. Torsion dystonia is a hereditary progressive disease, most often observed in Jewish families. Treatment is usually ineffective, but sometimes levodopa helps. In some patients, ventrolateral thalamotomy is effective. Orthopedic devices are sometimes useful.
b. Spasmodic torticollis is an idiopathic segmental dystonia involving the muscles of the neck. The disease is usually sporadic, but familial cases have also been described. The morphological substrate is not known. Pathological movements can be fast and repetitive or constant tonic. With the ineffectiveness of drug therapy, various conditioning methods are used, in particular sensory and positional feedback. The patient often finds movements or postures that facilitate hyperkinesis (compensatory techniques). In the past, surgical methods were used: transection of the spinal root of the accessory nerve or intradural transection of the anterior roots C1-C3. Partial spontaneous remissions for 3 years are observed in approximately 30% of patients.
in. Sometimes local dystonia occurs after minor injuries. Their pathogenesis is unknown.
d. Paroxysmal choreoathetosis and paroxysmal dystonia are rare clinical syndromes that may be hereditary or acquired.
1) Clinical manifestations in members of the same family are very variable. Seizures may be triggered by fright or movement. Choreoathetosis is usually asymmetrical and lasts, as a rule, a few seconds or minutes. Movement-induced (kinesogenic) seizures are treated with carbamazepine and phenytoin.
2) Paroxysmal non-kinesogenic dystonia is provoked by alcohol intake, emotional reactions or fatigue, it can last for hours. Clonazepam is effective. Sometimes Parkinson's disease develops later.
I. Tiki
1. General information. Tics are fast, coordinated, stereotyped movements. In this they differ from the chaotic and irregular choreic movements, often reminiscent of arbitrary ones. Tics are divided into simple and complex, acute, subacute and chronic.
a. Tics occur in 5% of children, with most disappearing during adolescence.
b. The most pronounced tics are observed in the syndrome of multiple chronic tics (Gilles de la Tourette's syndrome). In this disease, tics first appear at the age of 2-13 years, then they can periodically intensify. Boys get sick more often. Characterized by involuntary grunting, whistling, coughing, echolalia is possible. In about half of the cases, there is an involuntary shouting of swear words (coprolalia). At an early stage, tics can be suppressed by willpower.
2. Treatment
a. Haloperidol is the drug of choice, but it often causes side effects. The initial dose is 0.5 mg / day in 3 doses, the maximum dose is limited by side effects (drowsiness, arterial hypotension, parkinsonism) and usually ranges from 8 to 16 mg / day in 4 doses. Rarely, leukopenia develops.
b. Pimozide is a dopamine receptor blocker similar to haloperidol. Sometimes it helps with the ineffectiveness of haloperidol. The initial dose is 1-2 mg / day orally, then it is gradually increased to 7-16 mg / day.
in. Clonidine (alpha2-adrenergic stimulant) is effective in about 50% of patients with recurrent tics while taking haloperidol. Start with 0.1 mg/day, then gradually increase the dose to 2 mg/day. The maximum improvement can occur only after 6 months. Clonidine works better on mental disorders than on tics. The main side effects are drowsiness, fatigue, orthostatic hypotension. The drug should not be withdrawn quickly because of the risk of rebound hypertension.
d. Tetrabenazine is reported to be effective in young people.
e. Calcium antagonists (nifedipine, flunarizine and verapamil) are also used.
e. Botulinum toxin A - see IV.3.1.b.
V. TREMOR
A. General information. Tremor is an involuntary, rhythmic, repetitive oscillation of one of the body parts relative to a fixed point.
B. Classification(see table 15.8). Tremor can be classified according to location, frequency, amplitude, association with voluntary movements. There are rest tremors, postural tremors, and intentional tremors.
B. Postural tremor
1. General information. This is the most common type of tremor. It is characterized by high frequency (7-12 s–1) and low amplitude. The tremor may be asymmetrical. Under certain conditions, postural tremor can also occur in healthy people, in particular during movements that require high precision or very great effort (physiological tremor). Tremor increases with fatigue, anxiety, general weakness, hypercapnia, after the abolition of a number of drugs, as well as with some metabolic and endocrine diseases (hypoglycemia, uremia, severe liver damage, thyrotoxicosis, poisoning with salts of heavy metals). Physiological tremor is aggravated by catecholamines (including amphetamines), theophylline, caffeine, lithium, tricyclic antidepressants, corticosteroids, antipsychotics, and valproic acid. Tremor can run in families. Tremor that appears in old age is called senile tremor. If the cause of the tremor cannot be identified, it is referred to as essential tremor. The diagnosis of essential tremor does not exclude the development of Parkinson's disease in the future.
2. Pathogenesis. The morphological substrate of most types of tremor is unknown. In physiological tremor and tremor caused by thyrotoxicosis, peripheral mechanisms seem to be of decisive importance. In essential, familial and senile tremor, an important role is also played by central mechanisms. In EMG, postural tremor usually manifests as synchronous contractions of agonists and antagonists, but sometimes they are alternating, as in Parkinson's disease.
3. Treatment
a. Tranquilizers are effective if the tremor is caused by anxiety. Diazepam is usually prescribed at 6-15 mg / day in divided doses.
b. A single intake of alcohol reduces postural tremor, this effect occurs after 10 minutes and lasts 3-4 hours.
in. Beta blockers
1) Propranolol is prescribed at 40-240 mg / day in several doses. The effect usually occurs after 48 hours of treatment. The initial dose is 20 mg 2 times a day. The drug is largely eliminated during the first passage through the liver. Propranolol is contraindicated in bronchial asthma and insulin-dependent diabetes mellitus; in addition, it can aggravate heart failure, AV block, bradycardia. Arterial hypotension, nausea, diarrhea, insomnia, hallucinations are also possible.
2) In bronchial asthma, the cardioselective beta-blocker metoprolol is preferable (although less effective). The initial dose is 50 mg 2 times a day, then it is gradually increased to 100 mg 2 times a day.
3) If it is difficult for the patient to take the drug several times a day, you can use the non-selective beta-blocker nadolol. Since nadolol has a long-term effect, it can be taken at 40-80 mg just once a day. However, being water-soluble, it does not penetrate the blood-brain barrier well. At the same time, sometimes nadolol reduces postural tremor, which indicates the important role of peripheral effects in the mechanism of action of beta-blockers.
Primidone (25-500 mg/day orally in divided doses) also reduces postural tremor. Some consider it the drug of choice for this type of tremor. The mechanism of action is unknown. Severe toxic effects are possible. In order to avoid vomiting and ataxia, the dose is increased very slowly.
e. Glutethimide (250-1000 mg/day).
e. Botulinum toxin A (see section IV.3.1.b) is used to treat essential tremor of the limbs or head when other methods are ineffective.
and. Ventrolateral thalamotomy is effective for severe postural tremor, as well as for congenital rubral or cerebellar intention tremor of the extremities, but does not help with head tremor.
D. Orthostatic tremor- an unusual variant of tremor, which is manifested by unsteadiness when standing, disappearing when walking. There are usually no significant abnormalities on neurological examination. Nevertheless, during exercise, EMG can detect a fast (up to 16 s–1) leg tremor caused by synchronous or less often alternating muscle contractions. Low doses of clonazepam (0.5-1 mg/day) are effective.
VI. ASTERIXIS
Asterixis can be thought of as a variant of a tremor that is manifested by non-rhythmic and usually slow flexion and extension of the limbs. EMG data show that it is caused by a temporary drop in muscle tone of the elongated limb. The morphological substrate has not been determined, it is only known that asterixis can be observed with focal lesions of the brain of vascular origin. More often it occurs with metabolic disorders (damage to the kidneys, lungs, liver), with Wilson's disease, as well as with the use of certain drugs, including metoclopramide and anticonvulsants. Treatment of asterixis is reduced to the treatment of the underlying disease.
VII. MYOCLONIA
A. General information. Myoclonus is fast, non-rhythmic twitches. A well-known example is the "night tremors" that occur when falling asleep. The morphological substrate of myoclonus is unknown, but it is believed that it is due to dysfunction of the monoaminergic neurons of the raphe nuclei. Often, myoclonus is accompanied by slow epileptiform waves on the EEG. After myoclonus, transient inhibition of normal postural mechanisms develops. According to EMG, myoclonus is characterized by sudden, rapid muscle contractions similar to normal, but usually shorter. Myoclonus can occur with toxoplasmosis, neuroblastoma, thallium poisoning, uremia, hepatic encephalopathy, drug intoxication (imipramine, penicillins, levodopa, MAO inhibitors, piperazines). Often myoclonus is associated with certain stimuli or activities. For example, for hypoxic brain damage, intentional myoclonus is characteristic - jerky, sharp muscle contractions that occur when approaching the target.
B. Treatment. If myoclonus is not due to any treatable disease, then therapy is usually unsuccessful. The following drugs sometimes give some effect:
1. Clonazepam (1.5 mg/day followed by an increase over 4 weeks to 7-12 mg/day in divided doses).
2. Valproic acid with posthypoxic myoclonus (the dose is gradually increased to 1600 mg / day).
3. Piracetam (18-24 g/day) as an additional remedy.
4. Oxytriptan (150-1600 mg/day orally 2-4 times a day) for posthypoxic myoclonus. It is used both alone and in combination with carbidof. Usually start with 100 mg of oxytriptan and 25 mg of carbidopa, then increase the dose every other day to the maximum tolerated (usually up to 3 g / day). Gastrointestinal disorders often occur, but they can be managed with antiemetics. At high doses, euphoria and mania are possible. Cases of the development of a disease resembling scleroderma during the treatment with oxytriptan are described.
5. Tetrabenazine for spinal myoclonus.
VIII. RESTLE LEG SYNDROME
Restless legs syndrome is characterized by unusual sensations in the muscles and bones of the lower legs and feet that occur at rest, often at night, and disappear with movement. In most cases, the cause cannot be established; at the same time, the syndrome occurs in chronic renal failure. Restless legs syndrome is often combined with periodic movements in sleep. Both of these conditions that cause sleep disturbance are treated in the same way. Commonly used are anticonvulsants (clonazepam and carbamazepine), dopaminergic drugs (levodopa and bromocriptine), clonidine, and narcotic analgesics
Definition of the concept of syndrome and symptom.
Violations of the functions of the nervous system, which may be the result of some diseases, pathological conditions that have developed after past illnesses, injuries of the nervous system, congenital developmental disorders, manifest themselves in the form of any deviations from the normal functioning of one or another functional system or one or another department nervous system.
- These deviations from normal functioning are a sign, or symptom, a pathological condition. Often, damage to any part of the nervous system manifests itself in the form of a set of symptoms. For example, damage to the cerebellum is manifested by a decrease in muscle tone, impaired coordination of movements, impaired balance, etc. Such a pathological condition, characterized by a persistent combination of several characteristic symptoms, is called syndrome or symptom complex. As a rule, the defeat of a certain part of the nervous system corresponds to a certain characteristic syndrome.
Major neurological syndromes. Syndromes of movement disorders. Peripheral paralysis. Central paralysis. Pathological synkinesis
Major neurological syndromes:
1. Syndromes of movement disorders: paralysis, paresis.
C-we have disorders of sensitivity and sense organs
3. C-we are lesions of the autonomic NS: vegetative-vascular dystonia, diencephalic syndrome, metabolic disorder, neuroendocrine diseases.
4. C-we are violations of higher mental functions: agnosia, asteriognosis, apraxia, speech disorders.
Syndromes of movement disorders
Spasticity- increased muscle tone
Rigidity- the state of the muscles, characterized by their compaction, tension and resistance to passive movements.
Paralysis -(from the Greek paralysis - relaxation), the absence of voluntary movements due to damage to the motor centers of the spinal cord and brain, pathways of the central or peripheral nervous system.
Paresis -(from Greek. paresis- weakening), weakening of arbitrary movements.
Paralysis and paralysis are the most common movement disorders in clinical practice.
monoplegia– paralysis of one limb or half of the body.
hemiplegia- damage to both limbs on the same side
Hemiparesis- weakening of voluntary movements of the limbs on one side (monoparesis - weakness of one limb);
Paraplegia - paralysis of both lower or upper limbs (lower and upper).
Tetraplegia- paralysis of all 4 limbs.
tetraparesis- weakening of voluntary movements in all 4 limbs.
Central (spastic) paralysis or paresis- damage to the motor centers in the cerebral cortex, as well as the motor pathway throughout the hemispheres and brain stem; characterized by the inability to produce voluntary movement due to weakness in the limbs. The impossibility of voluntary movements with the preservation and even intensification of the intensity of elementary reflex motor acts.
Peripheral, or flaccid, paralysis characteristic of damage to neurons in the brainstem and spinal cord. It is characterized by loss of reflexes, hypotension, and degenerative muscle atrophy.
Hyperkinesis - involuntary excessive movements caused by contraction of the muscles of the face, trunk, limbs, less often the larynx, soft palate, tongue, external muscles of the eyes.
Synkinesia(Greek syn- together kinēsis movement; synonym: associated movements, friendly movements) - involuntary muscle contractions and movements accompanying an active motor act.
Ataxia- impaired coordination of movements, when movements become awkward, balance is disturbed when walking, moving (dynamic ataxia) and standing (static ataxia).
