Clonuses of the feet and kneecaps. InternetAmbulanceMedical portal. Reflex distortions: from increase to decrease

Clonus is a neurological condition that occurs when the nerve cells that control muscles become damaged. This damage causes involuntary muscle contractions or spasms.

Symptoms are common in several different muscles, especially the limbs. These include:

• ankles;
• knees;
• calves;
• wrists;
• jaw;
• biceps.

Damaged nerves can lead to muscle malfunction, leading to involuntary contractions, muscle tension, and pain.

Clonus is a pathology that can cause muscle spasms for a long period. This pulsing can lead to muscle fatigue.

Due to constant stress, clonus can make everyday life stressful and exhausting. In this article, you will learn more about the causes and treatment of this condition.

While researchers don't understand the exact causes that cause clonus, it appears to be related to damaged nerve connections in the brain.

A number of chronic diseases are associated with clonus. Since these diseases require specialized treatment, the outcome may vary in each case.

Diseases that can cause clonus:

• Multiple sclerosis is an autoimmune disorder that attacks the protective sheath around nerves. The resulting damage disrupts nerve signals in the brain.
• Stroke - due to a blood clot, part of the brain experiences oxygen starvation. A stroke can cause clonus if the area of ​​the brain that controls movement is damaged.
• Infections such as meningitis or encephalitis can damage brain cells or nerves in advanced cases.
• Serious injuries, such as a head injury from a major accident, can also damage nerves in the brain or spinal cord.
• Serotonin syndrome is a potentially dangerous reaction that occurs when too much serotonin builds up in the body. This buildup can be caused by drug abuse, but can also be caused by high doses of drugs or mixing certain drugs.
• A brain tumor can also cause clonus.

Other causes of clonus include anything that can affect nerves or brain cells:

• epilepsy;
• cerebral paralysis;
• Lou Gehrig's disease;
• anoxic brain injury;
• hereditary spastic paraparesis;
• kidney or liver failure;
• overdoses of drugs such as the synthetic opiate tramadol, which is a powerful pain reliever;

Diagnostics

To diagnose clonus, doctors may first physically examine the most affected area. If a muscle contracts while a person is in the doctor's office, they can monitor the contraction to see how fast the muscle is pulsing and how many times it contracts before stopping.

Doctors then order a series of tests and tests to confirm the diagnosis. They may use magnetic resonance imaging (MRI) to check for damage to cells or nerves.

Blood tests can also help identify markers for various conditions associated with clonus.

A physical test may also help doctors identify clonus. During this test, the patient is asked to quickly bend the leg so that the toes point upwards and then hold the muscles. This can cause prolonged throbbing in the ankle. A number of these pulses may indicate clonus. This may not be the basis for a diagnosis, but it can help guide the diagnostic process in the right direction.

Treatment

Treatment for clonus varies depending on the underlying cause. Doctors may try many different treatments before finding the one that works best for a particular patient.

Medications

Sedative and muscle relaxant drugs help reduce symptoms. Doctors often recommend these drugs primarily for people experiencing cloning.

Medications that may help with clonus reduction include:

• Baclofen;
• Dantrolene;
• Tizanidine;
• Gabapentin;
• diazepam;
• Clonazepam.

Sedative and anti-spasmodic drugs can cause drowsiness. Patients taking these medicines should not drive or operate heavy machinery.

Other side effects may include mental confusion, lightheadedness, or even trouble walking. You should discuss these side effects with your doctor, especially if they may interfere with daily activities.

Physiotherapy

Working with a physical therapist to train the muscles can help increase the range of motion in the injured area.

Botox injections

Some people have clonus that respond well to Botox injections. Botox therapy involves the injection of certain toxins. The effects of Botox injections wear off over time, so a person will need repeat injections on a regular basis.

Surgery

Surgery is often the last resort. During the clonus treatment procedure, surgeons will cut off parts of the nerve that cause abnormal muscle movements, which should relieve symptoms.

home remedies

While medical treatments, home remedies can be helpful to support these efforts.

Using heat packs or using warm baths can relieve pain, and applying cold packs can help reduce muscle pain. Stretching and yoga can help increase your range of motion.

You can use a magnesium supplement or a magnesium salt bath to help relax your muscles. You should consult your doctor before taking magnesium as it may interact with other medications.

Forecast

Clonus has a different prognosis depending on the underlying cause. If a sudden injury or illness causes clonus muscle spasms, the symptoms are likely to disappear over time or respond well to physical therapy.

Chronic diseases such as multiple sclerosis, meningitis, or stroke may require long-term treatment for symptoms. Clonus may worsen if the underlying condition progresses.

The article was written based on materials from the Medical News Today website.

During a clinical examination of a patient, the doctor checks a lot of reflexes stretching to determine the degree of background, or "tonic", excitation transmitted from the brain to the spinal cord. This reflex is called as follows.

Knee and other muscle reflexes. In the clinic, excitation of the knee and other muscle reflexes is usually used to determine the sensitivity of stretch reflexes. To call a knee jerk, they hit the tendon of the patella with a neurological hammer; this instantly stretches the quadriceps femoris, which causes a dynamic stretch reflex that causes the lower limb to twitch forward. The figure shows the myogram of the quadriceps muscle recorded during the knee jerk.

Similar reflexes can be taken from almost any muscle in the body by striking either their tendon or the belly of the muscle itself. In other words, all that is required to elicit a dynamic stretch reflex is a sudden stretch of the muscle spindles.

neurologists use muscle reflexes to assess the degree of relief of the spinal centers. When a large number of facilitating impulses are transmitted from the upper regions of the central nervous system to the spinal cord, muscle reflexes are greatly enhanced. Conversely, if the facilitating impulses are suppressed or do not work, muscle reflexes are markedly weakened or absent.

These reflexes more often used to determine the presence or absence of muscle spasticity in lesions of the motor areas of the brain or diseases that excite the bulboreticular facilitating area of ​​the brainstem. Usually, extensive lesions of the motor areas of the cerebral cortex, in contrast to the underlying motor regulatory areas (especially lesions associated with strokes or brain tumors), are accompanied by excessively enhanced muscle reflexes on the opposite side of the body.

Clonus - oscillation of muscle reflexes. Under certain conditions, muscle reflexes can oscillate. This phenomenon is called clonus. Oscillation is most easily explained using the example of ankle clonus.

If a person, standing on the tips of the toes(on tiptoe), suddenly stands on the whole foot, stretching the calf muscle, impulses from the muscle spindles are transmitted to the spinal cord. At the same time, the stretched muscle is reflexively excited and again raises the body. After a fraction of a second, the reflex contraction of the muscle stops, and the body "falls" on the foot again, thus stretching the spindles a second time.

Again dynamic stretch reflex lifts the body, but it also stops after a fraction of a second, and the body falls again, starting a new cycle. Often the calf stretch reflex continues to oscillate for a long time. This is the clonus.

Clonus usually develops only if the stretch reflex is strongly sensitized by facilitating impulses from the brain. For example, in a decerebrated animal, in which stretch reflexes are greatly facilitated, clonus develops easily. To determine the degree of relief of the spinal cord, neurologists test the patient for clonus by suddenly stretching the muscle and using a constant stretching force. If clonus develops, the degree of relief is undoubtedly high.

Rice. 32. Pyramidal syndrome. Ways of causing pathological reflexes. Carpal pathological reflexes: 1 - analogue of the Rossolimo reflex; 2 - Zhukovsky reflex; 3 - Jacobson's reflex - Weasel. Extensor and flexion foot pathological reflexes: 4 - Babinsky's reflex; 5 - Oppenheim reflex; 6 - Schaeffer reflex; 7 - Gordon's reflex; 8 - Rossolimo reflex; 9 - ankylosing spondylitis 1; 10 - Zhukovsky reflex; 11 - Bekhterev II reflex. Methods for inducing the main pathological protective reflexes: 12 - Marie-Foy test

Clones of the feet, kneecaps and hands - rhythmic muscle contractions in response to stretching of the tendons - are the result of a sharp increase in tendon reflexes. With gross lesions of the pyramidal tract, clonus often occurs spontaneously when the position of the limb changes, when touched, or when trying to change the posture. In less severe cases, causing clonus requires a sharp stretching of the tendons, which is achieved by rapid dorsiflexion of the patient's foot (foot clonus), hand (hand clonus) or sharp abduction of the patella down (patella clonus). Pathological reflexes. There are carpal and foot (flexion and extensor) pathological reflexes, as well as reflexes of oral automatism (Fig. 32). Carpal pathological reflexes are characterized by the fact that, with various methods of their evoking, reflex slow flexion of the fingers occurs. The carpal analogue of the Rossolimo symptom - the examiner applies a short, jerky blow to the tips of the II - V fingers of the patient's hand, which is in the pronation position, with his fingertips. Zhukovsky's symptom - the examiner strikes with a hammer in the middle of the patient's palm. Symptom of Jacobson-Lask - the examiner strikes with a hammer on the styloid process. Foot pathological reflexes are divided into flexion and extensor. Flexion reflexes are characterized by slow flexion of the toes (similar to pathological carpal reflexes). Rossolimo's symptom - the examiner with his fingertips delivers a short blow to the tips of the II - V toes of the subject's foot. Zhukovsky's symptom is caused by a hammer blow in the middle of the sole at the base of the fingers. Ankylosing spondylitis I is caused by a hammer blow to the rear of the foot in the region of the IV-V metatarsal bones. Ankylosing spondylitis II is caused by a blow of the hammer on the heel of the subject. The extensor reflexes are characterized by the appearance of extension of the big toe; II - V fingers diverge fan-shaped. Babinsky's symptom - the examiner passes the handle of the neurological hammer or the blunt end of the needle along the outer edge of the sole. Oppenheim's symptom - the examiner holds the back surface of the middle phalanx of the II and III fingers along the anterior surface of the lower leg of the subject. Gordon's symptom is caused by compression of the calf muscle of the subject. Schaeffer's sign is caused by compression of the Achilles tendon. Poussep's sign is caused by streak irritation along the outer edge of the foot. In response, the little finger is abducted to the side. protective reflexes. With pain and temperature stimulation of a paralyzed limb, it involuntarily withdraws (it bends from a straightened position, and unbends from a bent position). For example, with a sharp painful flexion of the toes, a triple flexion of the leg occurs in the hip, knee and ankle joints (Bekhterev's symptom - Marie - Foix). Synkinesia - involuntary arising friendly movements that accompany the performance of active movements. They are divided into physiological (for example, waving the arms while walking) and pathological. Pathological synkinesis occurs in a paralyzed limb with damage to the pyramidal tracts and is due to the loss of inhibitory influences from the cerebral cortex on intraspinal automatisms. During the first month of life in a child, physiological extensor synkinesis is determined - the so-called triple extension. It consists in the extension of the limbs, body and head with pressure on the soles. The Perez reflex, described in Chapter 10, can also be attributed to the synkinesis of infancy. Pathological synkinesis is divided into global, coordinating and imitation. Global synkinesis is a contraction of the muscles of the paralyzed limbs, which manifests itself in the usual movement for their function, which occurs when the muscle groups are strained on the healthy side. For example, when trying to rise from a prone position or get up from a sitting position on the paretic side, the arm is bent at the elbow and brought to the body, and the leg is unbent. Coordinator synkinesis - when you try to make a movement with a paretic limb, another movement involuntarily appears in it. Tibial synkinesis (Strumpell's tibial phenomenon) - when you try to flex the lower leg, the foot and thumb dorsiflexion occurs. Pronator synkinesis - when you try to bend the paretic arm in the elbow joint, simultaneous pronation of the forearm occurs. Radial synkinesis - when you try to compress the paretic hand into a fist, dorsiflexion of the hand occurs. Imitative synkinesis is an involuntary repetition in the paretic limb of those movements that are performed in a healthy limb. Raymist's synkinesis - if the examiner resists the adducting and abducting movements of the healthy leg of the patient, then similar movements appear in the paretic leg. The decrease or absence of skin reflexes (abdominal), observed: on the side of paralysis, is explained by the fact that the segmental reflex arc of skin reflexes functions only in the presence of a stimulating effect of the cerebral cortex. With central paralysis, this connection can be broken. Central paralysis is often also accompanied by disorders of urination and defecation. The centers of urination and defecation are located in the gray matter of the spinal cord at the level of 1 - III lumbar and II - IV sacral segments. Voluntary control of urination is provided due to the connections of these centers with the cerebral cortex. Cortical innervation is carried out along the paths passing in the lateral cords of the spinal cord near the pyramidal tract, therefore, bilateral damage to the latter is accompanied by a disorder of pelvic functions. With a central disorder, periodic urinary incontinence is observed (reflex emptying of the bladder when it is stretched by urine, occurring periodically, without voluntary control), sometimes urinary retention, imperative urge to urinate (see Chapter 5). The scheme of the two-neuron motor cortico-muscular pathway excludes the combination of peripheral and central paralysis (Table 2). The defeat of the second neuron always entails the development of peripheral paralysis, regardless of the state of the pyramidal pathway. So, with damage to the gray matter of the spinal cord at the level of the lumbar thickening, lower paraplegia of the peripheral type will inevitably occur, regardless of the presence or absence of damage to the overlying lateral cords with pyramidal tracts. In practice, however, one has to deal with diseases (for example, amyotrophic lateral sclerosis), in which symptoms are revealed that are inherent in both central and peripheral paralysis: a combination of atrophy and grossly expressed hyperreflexia, clonuses, pathological reflexes. Table 2. Symptoms of central and peripheral paralysis

Rice. 33. The main syndromes of motor disorders in the defeat of the central and peripheral motor neurons. Localization of the lesion: I - right anterior central gyrus; (I - motor zone of the right inner capsule; III - midbrain; focus on the right; IV - bridge of the brain, focus on the right; V medulla oblongata, focus on the right; VI - VIII - cross of the pyramids; IX - half lesion of the spinal cord on the right in the lower thoracic region: 1 - cortical-nuclear pathway: 2-3 - cortical-spinal

This is due to the fact that a progressive degenerative or acute inflammatory process mosaically, selectively affects the pyramidal tract and cells of the anterior horn of the spinal cord, as a result of which the central motor neuron is affected for some muscle fibers (and central paralysis develops), for others - the peripheral motor neuron (peripheral motor neuron develops). paralysis). The progression of the process in amyotrophic lateral sclerosis leads to an increasing generalization of damage to the motor neurons of the anterior horn, while hyperreflexia and pathological reflexes begin to gradually disappear, giving way to symptoms of peripheral paralysis (despite the continued destruction of pyramidal fibers). In recent years, ideas about the pyramidal system have been largely revised, in particular, data have been obtained that the so-called pyramidal syndrome (central paralysis or paresis) is not the result of an isolated lesion of the pyramidal pathway and is largely associated with simultaneous damage to the descending pathways of the extrapyramidal system. . Experiments with cutting the pyramids of the medulla oblongata and pedunculotomy (cutting the pyramidal pathway in the brain stem) revealed only a slight impairment of motor functions in the form of a change (often a decrease) in muscle tone and a disorder of fine discrete movements of the hand (opposition of the thumb and forefinger, necessary to capture small objects), and these locomotor disorders were predominantly transient. Thus, an isolated lesion of the pyramidal tract does not cause those disorders that are clinically referred to as manifestations of the pyramidal syndrome, and, above all, does not cause the occurrence of spastic paralysis with tendon hyperreflexia. In evolutionary terms, the pyramidal pathway is one of the youngest in the central nervous system. It is absent in reptiles and birds, in which the reticulospinal system is the main motor function regulation system. The pyramidal path appears in higher vertebrates, and reaches its greatest development in animals that have fingers and are able not only to “grasp”, but also “collect”. The emergence of the pyramidal syndrome is associated with the involvement in the pathological process, along with the pyramidal path, of the fibers of the extrapyramidal system, originating from the motor zones of the cerebral cortex and closely related to the stem tonic and postural systems, including the red nucleus, the reticular formation, the vestibular apparatus, etc. In an isolated form, the pyramidal pathway has a facilitating tonic effect on the spinal motor mechanisms. The impact of the pyramidal path on the anterior horn motor neurons is carried out through the insertion path (2 - to the arm, 3 - to the leg): 4 - the nucleus of the oculomotor nerve; 5 - the nucleus of the facial nerve; 6 - core Neurological syndrome: I - II - contralateral hemiplegia and damage to VII, XII nerves in the central type; III - Weber's syndrome; IV - Miiyar-Gubler syndrome; V - Jackson's syndrome: VI - contralateral hemiplegia; VII - central paralysis of the arm on the side of the focus and contralateral central paralysis of the leg; VIII - homolateral hemiplegia; IX - homolateral mocells, which do not have synaptic inputs from peripheral afferents, due to which the pyramidal control of motoneurons is relatively independent of segmental afferentation. Currently, among the fibers of the pyramidal pathway, there are thick, rapidly conducting fibers that provide fast (phasic) motor reactions, and thin, slowly conducting fibers that provide tonic regulation of voluntary movements. These data on the functional significance of the pyramidal pathway indicate that the classic "pyramidal syndrome" is caused by damage not only to the pyramidal pathway, but also to the accompanying pathways of the extrapyramidal system. At the same time, the pyramidal symptom complex is so stereotyped that it makes no sense in the clinic to divide it into true pyramidal and extrapyramidal components. Classical representations are quite acceptable for their use in topical diagnostics. Symptomocomplexes of motor disorders arising from the defeat of various parts of the motor pathways. Peripheral nerve damage causes peripheral paralysis. There is atrophy of the muscles innervated by this nerve, atony (hypotension) of this muscle group, loss of reflexes. Due to the fact that the peripheral nerves are mixed, along with movement disorders, pain, sensory disturbances and autonomic disorders are observed in the zone of innervation of this nerve. With damage to the anterior roots, peripheral paralysis of the muscles innervated by this root develops, fascicular twitches. Damage to the anterior horns of the spinal cord causes peripheral paralysis in the zone of innervation of this segment. Its features are the early onset of atrophy, reactions of degeneration, the presence of fibrillar twitches. The anterior horns of the spinal cord contain various groups of cells that innervate the corresponding muscles. The defeat of a separate group of cells leads to atrophy, atony of certain muscles (mosaic lesions). As a result of damage to the anterior horns of the spinal cord on both sides in the segments C5-Th, (cervical thickening), peripheral paralysis of the hands occurs (upper paraplegia or upper paraparesis). Damage to the anterior horns of the spinal cord on both sides at the level of the lumbar thickening causes peripheral paralysis of the lower extremities (lower paraplegia or paraparesis). With the defeat of the lateral funiculus of the spinal cord (tractus corticospinalis), central paralysis of the muscles develops below the level of the lesion. When the process is localized in the thoracic spinal cord, paralysis of the leg occurs on the side of the focus, when the process is localized above the cervical thickening, central paralysis of the arm and leg occurs. The defeat of the cauda equina causes peripheral paralysis of the lower extremities, a disorder of urination of the peripheral type, a disorder of sensitivity in the perineum and lower extremities. Sharp pains, asymmetry of symptoms are characteristic. Due to the defeat of the cerebral cone, there is a loss of sensitivity in the perineal region, a disorder of urination of the peripheral type (true urinary incontinence). With damage to the spinal cord at the level of L1-2-Si (lumbar enlargement), flaccid paralysis and anesthesia of the lower extremities, central urination disorder develop. The result of the Lesions of the thoracic region (Thj-Th) are spastic paralysis of the lower extremities, central urination disorder, violation of all types of sensitivity according to the conduction type. Damage to the spinal cord at the level of Sb - Th, (cervical thickening) causes peripheral paralysis of the lower extremities, impaired sensitivity of the conduction type, and central urination disorder. With damage to the spinal cord at the level C, - C4, tetraplegia and loss of all types of sensitivity below the level of the lesion, paresis or paralysis of the diaphragm, central urination disorder (retention, periodic urinary incontinence) develop. The defeat of the pyramidal path in the area of ​​the pyramidal decussation leads to paralysis of the arm on the side of the focus, the leg on the opposite side (Fig. 33). Damage to the pyramidal tract in the brain stem causes central hemiplegia on the opposite side. Usually, in this case, the nuclei of the cranial nerves or their roots are involved in the process, which is accompanied by the occurrence, in addition to contralateral hemiplegia, of peripheral paralysis of the muscles of the tongue, face, and eyeball on the side of the focus (alternating syndrome). Alternating syndromes allow you to determine the localization of the lesion of the brain stem. For example, with a focus in the midbrain region, homolateral peripheral paralysis of the muscles of the eye (the nucleus of the III nerve, its root) is combined with contralateral hemiplegia. As a result of damage to the pyramidal tract in the internal capsule, uniform hemiplegia occurs on the opposite side. At the same time, there is a central lesion of the VII and XII pairs of nerves (due to a concomitant interruption of the corticonuclear pathways leading to the motor nuclei of the brainstem). The defeat of the anterior central gyrus is the cause of monoplegia (monoparesis). Irritation of the anterior central gyrus causes epileptic convulsive seizures. Seizures can be local (Jacksonian epilepsy) or generalized.

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STRIOPALLIDAR SYSTEM. RESEARCH METHOD. SYNDROMES OF DEFEAT The cortico-muscular pathway, discussed in the previous section, provides an arbitrary contraction of one or another muscle. However, a single complete motor act, no matter how primitive it may be, requires the coordinated participation of many muscles. The simplest movement - raising the arm - is provided by the contraction of the muscles of the shoulder girdle, but at the same time the muscles of the trunk and lower extremities, restoring the correct position of the center of gravity of the body. The quality of movement depends not only on the type and number of muscles that implement it. Often the same muscles are involved in the implementation of various movements; the same movement can, depending on the conditions, be performed either faster or slower, with more or less force. Thus, to perform a movement, it is necessary to involve mechanisms that regulate the sequence, strength and duration of muscle contractions and regulate the choice of the necessary muscles. In other words, a motor act is formed as a result of a sequential activation of individual neurons and fibers of the cortico-muscular pathway, coordinated in strength and duration, that gives orders to the muscles. This inclusion is ensured with the participation of almost all motor systems of the brain and, above all, the extrapyramidal system and its striopallidar division. The extrapyramidal system includes the structures of the cerebral cortex, subcortical ganglia, cerebellum, reticular formation, descending and ascending pathways. Arbitrarily performing this or that action, a person does not think about which muscle should be included in the required Lyoment, does not keep in his conscious memory a consistent working scheme of a motor act. Habitual movements are made mechanically, imperceptibly for attention, the change of some muscle contractions by others is involuntary, automated. Motor automatisms guarantee the most economical use of muscle energy in the process of performing a movement. A new, unfamiliar motor act is energetically more wasteful than the usual, automated one. The swing of a mower's scythe, the blow of a blacksmith's hammer, the running of the musician's fingers - to the limit honed, energetically stingy and rational automated movements. Improvement of movements - in their gradual economization, automation, provided by the activity of the striopallidary system. The striopallidary system is divided according to its functional significance and morphological features into striatum and pallidum. The caudate nucleus and the shell are combined into a striatal system. The pale ball, black substance, red nucleus, subthalamic nucleus make up the pallidar system. The pallidum contains a large number of nerve fibers and relatively few large cells. The caudate nucleus and putamen include many small and large cells and a small number of nerve fibers. There is a somatotopic distribution in the striatal system: in the oral sections - the head, in the middle - the arms and trunk, in the caudal sections - the legs. There is a close relationship between the striatal and pallidar systems. The striatal system is "younger" than the pallida system, both phylogenetically and ontogenetically. It first appeared only in birds and is formed in humans by the end of the prenatal period, somewhat later than the pallidum. Pallidar system in fish and striopallidar. in birds, they are the highest motor centers that determine the behavior of the animal. Striopallidar devices provide diffuse, massive movements of the body, coordinated work of all skeletal muscles in the process of movement, swimming, flight, etc. The vital activity of higher animals, humans requires a finer differentiation of the work of motor centers. The needs of movements that are purposeful, productive in nature can no longer be satisfied by the extrapyramidal system. In the forebrain cortex, a higher apparatus is created in the course of evolution, coordinating the coordinated function of the pyramidal and extrapyramidal systems that direct the execution of complex movements. However, having moved to a subordinate, “subordinate” position, the striopallidary system did not lose its inherent functions. The difference in the functional significance of the striatum and pallidum is also determined by the complication of the nature of movements in the process of phylogenesis. "Pallidary" fish, moving in a state of suspension in the water with throwing, powerful movements of the body, should not "concern" about saving muscle energy. The needs of such a motor act are fully satisfied by the work of the pallidary system, which provides movements that are powerful and relatively accurate, but energetically wasteful, excessive. A bird forced to do a tremendous amount of work in flight and not being able to suddenly interrupt it in the air must have a more complex motor apparatus, which prudently regulates the quality and quantity of movements, the striopallidary system. The development and inclusion of motor systems in human ontogenesis follows the same sequence. Myelination of the striatal tract ends only by the 5th month of life, therefore, in the first months, the pallidum is the highest motor organ. The motility of newborns has obvious "pallidar" features. The movements of a child up to 3-4 years old and the movements of a young animal (puppy, deer, hare, etc.) have a great similarity, which consists precisely in excess, freedom, and generosity of movements. The richness of the child's facial expressions is characteristic, also indicating a certain predominance of "pallidarity". With age, many human movements become more and more habitual, automated, energetically prudent, stingy. Smiling ceases to be a permanent facial expression. The degree, solidity of adults is the triumph of the striatum over the pallidum, the triumph of the sober prudence of automated movements over the wasteful generosity of the child's still "inexperienced" striopallidary system. The process of learning any movement, aimed at automating a motor act, has two phases. During the first phase, which is conditionally called pallidar, the movement is excessive, excessive in strength and duration of muscle contraction. The second phase of rationalization of movement consists in the gradual development of the energy-efficient, most efficient (with a minimum expenditure of Forces) method of movement that is optimal for a given individual. The striopallidary system is the most important tool in the development of motor automatisms, which in an adult are purposefully selected and implemented by the higher cortical centers of praxis.

The relative "pallidarity" of the child is due not only to the immaturity of the striatum, but also to the fact that the child is still in the stage of motor learning in its first, pallidar phase. The older the child, the more and more motor acts are automated, i.e., they cease to be "pallidar". Along with this, the immaturity of the striatum and the predominance of "pallidarity" in newborns are, as it were, planned in advance, since it is precisely "pallidarity" that a child needs in the first period of extrauterine life. The striopallidary system has numerous connections: paths connecting the formations of the striopallidary system; pathways connecting the striopallidar system with the final motor pathway and muscle; mutual connections with various parts of the extrapyramidal system and the cerebral cortex, and, finally, afferent pathways. There are several ways to deliver impulses from the striopallidar system to the segmental motor apparatus: 1) the Moscow red nuclear-spinal pathway from the red nuclei; 2) vestibulo-spinal tract from the vestibular nucleus; 3) reticulospinal tracts from the reticular formation; 4) tectospinal (cover-spinal) path from the quadrigemina; 5) paths to the motor nuclei of the cranial nerves. The striopallidary system, which is responsible for the involuntary performance of motor acts, must receive comprehensive information about the state of muscles, tendons, the position of the body in space, etc. (Fig. 34, 35).

Rice. 34. Extrapyramidal The afferent systems that serve the striopallidum (information impulses from the "collector of sensitivity" - the thalamus, from the cerebellum, the reticular formation, corrective signals from the cortex, etc.) create, together with efferent paths, feedback rings with a continuous stream of informing and corrective, commanding signals. The circulation of impulses does not stop, uniting all motor and afferent systems into a single whole. Rice. 35. Block diagram of the influence of the extrapyramidal system on the spinal motor neuron.

When the nuclei of the extrapyramidal system and their connections are damaged, various symptoms occur. The main ones are hypotonic-hyperkinetic and akinetic-rigid syndromes. Violations of the extrapyramidal system are manifested in the form of changes in motor function, muscle tone, vegetative functions, emotional disorders. Rice. 36. Striopallidar syndromes. A - posture of the patient with akinetic-rigid syndrome; B - postural phenomena: a - Westphalian; E - hemitremor; 1 - caudate nucleus; 2 - shell: 3 - pale ball; 4 - black matter; 5 - subthalamic nucleus; 6 - red core.

CLONUS (clonus; Greek klonos turmoil, hustle) - fast rhythmic movements due to jerky contraction of a single muscle or group of muscles. The term is used to characterize movements caused by both spontaneous muscle contractions (clonic convulsions) and contractions caused by certain techniques. Spontaneous clonic convulsions, heterogeneous in their mechanism of origin, include K. of the soft palate, tongue, clonic convulsions during epileptic seizures, etc. (see Hyperkinesis, Epilepsy).

When examining a patient, K. is called up by special techniques, which are based on a quick jerky stretching of the muscle and its tendon; at the same time, the appearance of K. indicates a partial or complete loss of suprasegmental, primarily pyramidal, influences.

Violation of suprasegmental regulation is accompanied by a decrease in the threshold of segmental reflexes, as a result of which stretching of the muscle and its tendon leads to a reflex contraction of the muscle - its shortening. Shortening of the muscle, which counteracts its artificial stretching, limits the flow of facilitating impulses and increases the flow of inhibitory impulses to the motor neuron, and then the excitation of the motor neuron stops, the muscle relaxes. Since the stretching of the muscle and tendon artificially continues, the muscle stretches again and the resulting excitation of the motor neuron leads to its repeated contraction. There comes a rhythmic alternation of contraction and relaxation of the muscle. The emergence of K. is combined with a sharp increase in tendon reflexes, so K. is considered as one of the manifestations of hyperreflexia (see Reflexes, pathological).

There are K. of the patella, foot, big toe, hand, chin, etc.

To. of a patella it is possible to cause at position of the patient on back with the outstretched legs. Holding the patella between the thumb and forefinger, the doctor makes a quick jerky shift down and holds it in this position, in response, there is a rhythmic alternation of contraction and relaxation of the quadriceps muscle. K. of the foot is called in the same position of the patient, the leg is bent at the hip and knee joints, a quick jerky rear flexion of the foot is performed and it is held in this position; in response, the foot rhythmically flexes and unbends. K. of the foot can be caused in the same position by hitting the calcaneal (Achilles) tendon with a hammer. K. of the big toe, brushes cause them by quick, jerky extension and holding in this position; K. chin - quick jerky pulling down and holding the lower jaw in this position. The force of active stretching of the muscles when evoking K. should not counteract muscle contraction.

The presence of K. indicates an organic lesion of the brain or spinal cord. In patients with neuroses (see), in particular with hysteria, an attempt to cause K. can lead to jerky contractions of the muscles of a changing pace, amplitude and rhythm (pseudoclonus), which makes it possible to distinguish> them from K. as a symptom of an organic lesion of the brain and spinal cord .

Bibliography: Krol M.B. and Fedorova E.A. Major neuropathological syndromes, p. 370, M., 1966, bibliogr.; Triumfov A. V. Topical diagnosis of diseases of the nervous system, p. 18, L., 1974; G h u s i d J. G. Correlative neuroanatomy functional neurology, Los Altqs, 1970.

An extreme manifestation of an increase in tendon reflexes are the so-called clonuses. Clonuses are rhythmic contractions of a muscle resulting from stretching of its tendon. In essence, clonus is a chain of consecutive tendon reflexes caused by continuous stretching of the tendon. The most common are clonuses of the patella and foot.

Clonus of the patella is caused by a sharp displacement of the patella downwards, and the retracted patella continues to be held in a displaced position. The subject lies on his back with straightened legs. The kneecap is captured by the thumb and forefinger of the examiner and jerkily shifted down.

The tendon is stretched m. quadricipitis, which attaches the muscle to the upper edge of the bag of the patella, which, with a very high knee jerk, is sufficient to cause muscle contraction, the tendon stretch does not stop, and the muscle contractions follow one after the other, causing the rhythmic movement of the patella.

Clonus of the foot is also caused in the supine position of the subject. With the right hand, the foot is captured by its distal part, the leg is bent at the knee and hip joints, with a sharp push, the foot is unbent at the ankle joint. As a result of the stretching of the Achilles tendon, rhythmic movements of flexion and extension of the foot occur (with an extreme degree of vivacity of the Achilles reflex).

Since clonuses of the patella and foot are only indicators of a significant increase in the knee and Achilles reflexes, they can be observed in all cases of hyperreflexia, including those not with an organic lesion of the nervous system. Unlike organic clonuses, clonuses with neurosis, physiological increase in reflexes, etc. usually insufficiently resistant, always evenly expressed on both sides and not accompanied by other organic symptoms.

Clonuses on the upper extremities are rarely observed, more often than others there is a clonus of the hand, resulting from a sharp jerky extension of it.

If a symmetrical decrease or increase in reflexes is not always a sign of damage to the nervous system, then their unevenness always indicates an existing organic disease. Irregularity of reflexes (anisoreflexia) occurs either as a result of a decrease in reflexes on one side (damage to the reflex arc in the nerve, roots or gray matter of the spinal cord), or an increase in it on the other (damage to the pyramidal pathway).

Establishing the non-uniformity of reflexes is, therefore, extremely important. Therefore, their study should be carried out carefully, hammer blows, dashed irritations, etc. must be applied accurately and be of the same strength when examining the right and left, it is advisable not to be limited to a single study, to cause reflexes by different methods, etc.

"Topical diagnosis of diseases of the nervous system", A.V. Triumfov

Flexion-elbow, or reflex from the tendon m. bicipitis, caused by a hammer blow on the biceps tendon at the elbow. The response is a contraction of the named muscle and flexion in the elbow joint. Reflex arc: n. musculo-cutaneus, V and VI cervical segments of the spinal cord. Deep, tendon reflex. To evoke it, the researcher takes the hands of the researched with his left hand and bends him ...

In order to judge the normal electrical excitability of nerves and muscles or establish certain deviations from the norm, it is necessary to know the average values ​​of electrical excitability obtained as a result of a study of a large number of healthy individuals. In the process of studying electrical excitability, it was found that contraction is most easily obtained from certain sections of nerves and muscles, from the so-called motor points, or points ...

The metacarpo-radial, or carporadial, reflex is caused by a blow of the hammer on the processus styloideus of the beam and consists of flexion at the elbow joint, pronation and flexion of the fingers. Not all of these reactions are obtained constantly: pronation is usually most clearly expressed. When evoking a reflex, the subject's arm should be bent at a right or slightly obtuse angle in the elbow joint, the hand should be in the middle ...