Ataxia (incoordination) is a violation of the coordination of the action (coordination) of various muscles, which is manifested by the disorder of purposeful movements and static functions. Ataxia is a fairly common motor impairment, with the force in the limbs retained completely or fairly insignificantly reduced. Movement becomes uncomfortable, inaccurate, there is a breakdown in their consistency and continuity, while walking and standing, the balance is disturbed.
To adequately perform absolutely any movement, a joint concerted work of a large number of muscle groups is necessary. Movement itself provides mechanisms that regulate the choice of the appropriate muscle groups, the duration and strength of individual muscle contractions and the sequence of their inclusion directly into the motor act itself. In the absence of coordination of the muscles-antagonists and synergists, the quality of movement changes with the loss of its proportionality and accuracy. Movements become intermittent, lose their smoothness, become awkward and excessive. The transition between the movements (for example, flexion-extension) is much more difficult. Such discoordination of movements is called locomotor (dynamic) ataxia
: Clinically, the following ataxia types are distinguished :
→ Cortical (frontal) ataxia - affects the cortex of the frontal or occipito-temporal region
→ Vestibular ataxia - the vestibular apparatus is affected
→ Cerebellar ataxia - affects the cerebellum
→ Zadnestolotbova (sensitive) ataxia - conduction of deep-tissue sensitivity is impaired
This disorder is observed in the case of lesions of the frontal lobes of the brain with damage to the bridge-lobular-cerebellar connections. The most severe disease manifests itself in the contralateral foci of limb injury (leg), characteristic disturbances of balance are observed, sometimes reaching the degree of astasia-abasia, there is a decrease in intelligence, memory and criticism. е , при приеме некоторых лекарственных средств (дифенин, карбамазепин и др.) Ataxia can develop as a consequence of the following neurological diseases: abscesses and brain tumors, funicular myelosis, multiple sclerosis, polyneuropathies, idiopathic and hereditary cerebellar ataxia, craniocerebral trauma, stroke, etc. In addition, this genetic disorder can develop with chronic or acute alcohol intoxication , vitamin E deficiency, poisoning with solvents and heavy metal salts, hypothyroidism , when taking certain medicines (diphenin, carbamazepine, etc.)
This disorder develops in the affected peripheral vestibular apparatus and is manifested by imbalances in the sitting, standing and walking position. Vestibular ataxia is manifested by dizziness (sensation of rotating surrounding objects), which are strengthened by movements of the head; in some cases, nausea and vomiting are observed, the musculo-articular feeling is preserved, there is no disturbance in the limbs
As the name implies, this disorder occurs when the cerebellum is affected, as well as its leading pathways, and is manifested by ataxia when standing (expressed in widely spaced legs) and walking, by dysmetry during any precise movements, by dysdiadochokinesis (a person can not quickly change one movement to another ), tremor in the extremities, asynergia (inconsistency of movements). When the cerebellar form of the disease is often observed a change in handwriting (macro, unevenness), speech by warehouses ("chopped speech"), muscle hypotension, nystagmus. The defeat of the cerebellar worm leads to ataxia of the trunk, the damage to the hemisphere of the cerebellum to the ataxia of the homolateral limbs
This condition develops in the event of damage to the conductors or receptors of the musculo-articular sensitivity at any site in the posterior roots, the brainstem, peripheral nerves, the visual hillock and the posterior columns of the spinal cord. Sensitive ataxia is manifested by abnormalities of gait, balance, defeat of limbs (when performing accurate movements the person misses), the musculo-articular feeling decreases; when the eyes are closed, the degree of sensitive ataxia is significantly increased (Romberg's test). In the case of damage to the posterior columns of the spinal cord, ataxia manifests itself as a characteristic muscular hyporeflexia and hypotension, while walking the patient disproportionately bends and unbends his legs, while striking the floor with a heel ("punching" gait)
This type of disease develops with a frequency of about 5 people per 100,000 population. Most often the disease develops in 10 - 15 years (not later than 25 years). Due to damage to the spinal cord and the cerebellum, progressive sensitivities and cerebellar ataxia are characteristic. Often there are skeletal anomalies (high arch of foot, kyphoscoliosis), light central paresis of limbs, damage to the heart muscle. For Friedreich's ataxia, the degree of progression is different, but most patients die before they reach the age of thirty
Hereditary idiopathic cerebellar ataxia
This type of ataxia develops in people older than 25 years, and its genesis is unclear. The first type of this disease manifests itself in progressive cerebellar ataxia. For the second type, a combination of ataxia with central paresis, symptomatology of the defeat of the autonomic nervous system (orthostatic hypotension), and basal ganglia
This condition is associated with aplasia of the cerebellum and is often combined with other congenital anomalies of development. The main syndrome is non-progressive cerebellar ataxia. Often when congenital, there is a good development of independent walking, motor skills, learning and self-service ability
Diagnosis of ataxia often does not cause difficulties and is based on the presence of typical clinical manifestations. Diagnosis is confirmed by the results of immunological examination of cerebrospinal fluid and blood. In addition to confirming the diagnosis, CT and MRI of the head are indicated. In case of suspicion of hereditary nature, a genetic examination is performed.
Rapidly increasing symptomatology of the disease is most often due to brain abscess, tumor, chronic alcohol intoxication or multiple sclerosis. Acute development of ataxia in most cases is caused by acute disorders of cerebral circulation in the cerebellum (infarction, hemorrhage, etc.). Episodic ataxia most often develops as a consequence of taking certain medicines (diphenin, carbamazepine), with multiple sclerosis, episodic hereditary ataxia. Slowly progressing ataxia develops in idiopathic and hereditary degenerative forms of the disease and multiple sclerosis.
Treatment of ataxia is symptomatic in most cases and is based on the therapy of the underlying disease. Idiopathic degenerative and hereditary forms of treatment are not subject to treatment. In addition, the social rehabilitation of the patient and the complexes of therapeutic gymnastics are of no small importance in the treatment.
The prognosis of ataxia is slight. The patient has a gradual progression of various neuropsychiatric disorders. In most cases, work capacity is markedly reduced. Even so, in case of prevention of intoxications, injuries, repeated infectious diseases and the timely conduct of adequate symptomatic treatment, patients can successfully survive to old age.
Prevention of ataxia is to exclude any possibility of related marriages. In addition, families where there are diagnosed patients with hereditary ataxia are not recommended to have children.