Ataxia and its variants
Ataxia is a violation of consistency in the work of the muscle group responsible for coordination. This is reflected in the difficulty of keeping the patient in balance during standing, walking and any movement. For such a disease, pronounced changes in the muscles of the limbs are not characteristic, the reasons for which it arises are of a central nature.
An exception is a concept such as ataxia intrapsychic, adopted in psychiatry. This definition denotes the discrepancy between human representations and their emotional state and is a sign of schizophrenia. For example, he rejoices, imagining that he is being tortured.
Control over the correctness and coordination of the trunk and limbs is carried out in various parts of the nervous system, and depending on the location of the lesion, different types of ataxia are isolated.
Ataxia species
Distinguish static ataxia when balance maintenance is impossible in a standing position, and dynamic( difficulty in moving).
For a practicing physician there is a convenient classification of such a pathology:
- Acute ataxia. Occurs in vascular accidents or some neoplasms with the course of a stroke, multiple sclerosis, infectious encephalitis, severe metabolic disorders, obstructive hydrocephalus, intoxications, conditions accompanied by a sharp rise in temperature.
- Subacute ataxia( develops within a few weeks).The reason can be any volumetric process, toxic lesions.
- Chronic progressive ataxia. These include spinocerebellar and cortical ataxia, as well as cerebellar ataxia, which occur with the involvement of other parts of the nervous system in the pathological process.
- Episodic ataxia. In childhood, it is observed as a process caused by a hereditary autosomal dominant disease. For adults, the appearance of such a symptom may indicate the consequences of transient ischemic attack, neoplasms of the brain with compression of its structures at the level of the large occipital opening, multiple sclerosis.
Cerebellar ataxia
This is the so-called generalized term for various types of coordination disorders in case of damage to the cerebellum. The features of the clinical picture depend on the degree, localization and type of lesion of this structural formation.
Symptoms with this ataxia can be very diverse. The shakiness of gait, slowness and awkwardness in movement, chanted or extended speech are noted. Visual control does not bring improvement. The patient, when walking widely puts his feet, can make deep slopes back or forward.
If the process affects the hemispheres of the cerebellum, then a very typical symptom is the tremor of the hands. The handwriting of this patient also changes, it becomes sweeping and illegible. A miss is noticed past the target and an increase in jitter as you approach it.
In children, cerebellar ataxia occurs as a hereditary pathology in an autosomal recessive or autosomal dominant type.
Sensitive( ataxia)
Occurs due to disruption of the operation of the posterior columns( fibers) of the spinal cord, which analyze information from the peripheral receptors of the joints and skin, spinal nerves serving as signal conductors from these sensitive endings, the thalamus. The defeat of these structures occurs as a result of
- tumor formation;
- multiple sclerosis;
- disease associated with vascular injury;
- vitamin deficiency( lack of B vitamins).
Sensory ataxia appears as a "stamping" gait. A person has lost the feeling of support, the step is obtained with disproportionate bending of the leg in the joints and with excessive force of lowering it down, as the patient feels that it seems to be falling off when walking.
If the upper limbs are involved in the process, then with outstretched arms, such a patient has obsessive movements in the fingers( pseudoathetosis).
The difference between sensitive and other ataxia is the deterioration of the condition in the absence of visual control( with closed eyes or poor lighting).
Cortical Ataxia
Appears when the frontal lobe of the cerebral cortex is affected. For this type of ataxia, the clinical picture is expressed in the manifestation of unsteadiness of the gait and corners of the trunk, as well as a strong slope or fall to the side corresponding to the side of the lesion. With a vast change in the patient is not at all able to walk or even stand. Control of vision improves coordination does not bring.
Often cortical ataxia is accompanied by a symptomatic complex, characteristic of the violation of the function of the frontal lobe: changes in the mental state, the appearance of a grasping reflex, the absence of smell, the appearance of hallucinations, including visual ones.
The main difference between cortical and cerebellar ataxia is a marked decrease in tonus in the limb with impaired function.
Frontal( cortical) ataxia occurs as a result of abscess, tumor formation, acute circulatory disturbance.
Labyrinth form of
Vestibular, or labyrinthine ataxia, occurs due to structural disturbances in one of the links forming the vestibular apparatus. This may be the cortical center of the temporal lobe, the nucleus in the stem department, the labyrinth or the vestibular nerve.
Clinical symptoms characteristic of this type of ataxia are manifested in the appearance of dizziness, which is amplified by a change in position, rotation of the head or trunk. Often it is observed even lying down and with closed eyes. All these signs can be accompanied by nausea and vomiting.
The patient makes any movements with great care and whenever possible smoothly. Often there is nystagmus and hearing impairment, a coarse change in coordination during standing or sitting, but there is no such thing as locomotor ataxia( involving the limbs), but speech remains normal.
Vestibular, or labyrinthine ataxia occurs after encephalitis, involving the brain stem, ear diseases, as a result of the tumor process. Often this symptom accompanies Meniere's disease.
Psychogenic ataxia
You can also note a separate type of ataxia - psychogenic or hysterical. For such a symptom is very characteristic of the pretentiousness of human movements. His walking is like skating or walking with stilts. The disorder has a functional character, and is not confirmed by the detection of organic pathology.
Psychogenic ataxia is characterized by the following features:
- the patient's complaints are very colorful, and their description does not correspond to the severity of the actual condition;
- is often preceded by stressful situations, when care of the disease seems to be the best way to avoid making decisions;
- clinical picture is not typical, which makes it difficult to diagnose;
- combination of personal characteristics of the patient with work in the medical field( "trying on the disease");
- frequent patient visits by physicians of various specialties.