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Inborn cerebellar ataxy
Cerebellum (for lat. cerebellum) at the person is located in a skull, around a nape. Usually the cerebellum has volume on average of 162 cubic cm, and its weight varies within 135-169 g. In a cerebellum two hemispheres between which its most ancient part — a worm is located. Besides, by means of three pairs of legs it is connected with a myelencephalon, with the bridge and a mesencephalon. It consists of white and gray substances, from the last bark of a cerebellum and pair kernels in his body form. The worm is responsible for balance and stability of a body, and a hemisphere — for the accuracy of movements. To maintain balance of a body, information from proprioceptors of various parts of a body and from other organizations which participate in control of position of a body of the person (the lower olives, vestibular nuclei) comes to a cerebellum.
At a tension of groups of muscles when performing purposeful actions, maintenance of position of a body in balance, nervous impulses get into a cerebellum. They pass from a spinal cord and from that part of a cerebral cortex which is responsible for the movements. Having passed a complex system of contacts, the flow of nervous impulses comes to a cerebellum which, in turn, carries out its analysis and issues "answer" which already gets to consciousness of the person, i.e. to a cerebral cortex and a spinal cord. Thanks to harmonious work of all bodies, the muscle work of a body becomes accurate and beautiful. Damages of a cerebellum and its worm are shown in disturbances of a statics, i.e. the person cannot steadily support the situation of stability of the center of gravity of a body, and also balance.
The term "ataxy" relatively to diseases of a nervous system is used since the time of Hippocrates, and then it meant "disorder" and "confusion", today understand a lack of coordination of movements as an ataxy. The ataxy is shown in disorder of gait and movements of extremities which are shown in trembling during the performing of actions, a promakhivaniya, and also disturbance of balance in position of a body standing and sitting.
Ataxy happens cerebellar, sensitive, vestibular and frontal. At damage of a cerebellum and its conduction paths there is a cerebellar ataxy. This disease is shown by ataxy symptoms when standing and walking. Gait of the patient with a cerebellar ataxy reminds gait drunk, he goes uncertainly, widely places legs, throws him here and there, usually towards an arrangement of the pathological center.
Tremor in extremities intentsionny, the person cannot quickly change position of a body. Also often the asynergia, that is inconsistency of movements can be observed, for example, at a body tilt back legs are not bent in knee joints therefore falling is possible. Very often at a cerebellar ataxy the "chopped" speech, on warehouses is observed, handwriting changes, sometimes — a hypomyotonia can be observed.
If defeat extends to cerebellum hemispheres, the ataxy of extremities from that party in which there is a hemisphere can develop if the worm is struck — the trunk ataxy develops.
If to put the patient with a cerebellar ataxy in Romberg's pose (that is to rise, having densely shifted legs, having pressed hands to a body and having raised the head), then this pose is unstable, the body of the person can be shaken, sometimes pulls some party, up to falling. If the worm is struck — that the patient falls back and if one of hemispheres — that towards the pathological center.
In a normality if there is a falling threat aside, the leg located from falling moves in the same direction, and another — comes off a floor, that is there is "hopping reaction". The cerebellar ataxy breaks these reactions if it is weak to push it aside, it easily falls (a pushing symptom).
At young age the nervous system of the person has rather high potential of neuroplasticity, i.e. property of a nervous system to be reconstructed quickly under the influence of external or internal changes. A series of repetitions of identical influence is necessary for development of neuroplasticity thanks to what in TsNS there are biochemical and electrophysiologic reorganizations. As a result of it, between cells of TsNS are formed new, or there are active old contacts. And at an ataxy, because of defeat of nervous tissues, it cannot be formed skills of thin and harmonious movements.
It should be noted that an ataxy meets approximately at from 1 to 23 persons on 100 thousand (prevalence depends on the region). Actually development of an ataxy is usually caused genetically, and symptoms of an inborn cerebellar ataxy are shown at children's age.
According to modern classifications, a cerebellar ataxy happens:
- The inborn cerebellar ataxy (which is not progressing when hemispheres or a worm of a cerebellum are underdeveloped or are absent).
- The autosomal and recessive ataxy arising at early age (Fridreykh's ataxy). Fridreykh's ataxy was described for the first time in 1861, and usually its symptoms are shown at children or young people till 25 flyings. The disease is shown also in ataxy symptoms, frustration of a statics, uncertain gait, decrease in a muscle tone. The arising disorder of sensitivity leads to decrease in tendon jerks. At Fridreykh's ataxy the abnormal skeletogeny, emergence of "Fridreykh's foot", i.e. a foot ukorochennost, its high arch is characteristic. The illness progresses rather slowly, but leads to an invalidism of patients, and a prikovannost to a bed.
- The recessive ataxy connected with a chromosome of X (A H-chromosomal ataxy). This type of an ataxy occurs very seldom, generally at males in the form of the progressing cerebellar insufficiency.
- Betten's illness inherited on autosomal recessively type is an inborn disease. The inborn cerebellar ataxy which is transferred on the first years of life in the form of disturbance of a statics, coordination of movements and a look is characteristic of it. I begin to hold the head such children by 2-3 years, and to go and speak — still later. With age the patient adapts in the state.
- Autosomal and dominant ataxy of late age (them a spinotserebellyarny ataxy still calls). Here Pierre Mari's illness belongs. This type of a hereditary cerebellar ataxy is shown at the age of 25-45, and strikes cells of bark and kernels of a cerebellum, spinotserebellyarny ways in a spinal cord and kernels of the bridge of a brain. Its signs are the ataxy and pyramidal insufficiency, intentsionny trembling, a tendinous hyperreflexia, the "chopped" speech. Sometimes — squint, a ptosis, decrease in sight. The cerebellum size gradually decreases, decrease in intelligence and depressions is very often observed. By the way, most of authors consider a cerebellar ataxy of Pierre Mari as a syndrome in which structure join olivopontotserebellyarny (Dezherina-Toma) and an olivotserebellyarny atrophy (Holmes's type), a cerebellar atrophy of Mari-Fua-Alazhuanina, and also an olivorubrotserebellyarny atrophy of Lermitt.
Symptoms of an inborn cerebellar ataxy
The general symptoms for all types of an ataxy are atactic manifestations. This disturbance of harmonious work of all muscles for achievement of the goal of the act of the movement. Symptoms of an inborn cerebellar ataxy include a dismetriya — disproportion of ongoing efforts for performance of purposive movement. The dyssynergia when coordination of separate muscles, intentsionny trembling, a rhythmical deviation from the correct trajectory of purposive movement which increases at approach to the purpose is broken is observed.
Frequent signs instability in vertical position, a nystagmus (the rhythmical fast movements of an eyeglobe), and also the abrupt speech, accents on each syllable. A symptom of a cerebellar ataxy at children is that the child late begins to sit and go, and his gait is not sure, as if "swings" the child.
Symptoms of an inborn cerebellar ataxy are shown by a delay of motive functions of the child, he late begins to sit, go, there is a lag of mental development, a speech delay. Usually by 10 years there is compensation of brain functions.
To confirm the diagnosis, it is necessary to carry out research KT and MPT, and also DNA researches for definition of genes which lead to development of certain forms of pathologies.
Treatment of an inborn cerebellar ataxy
Treatment of a disease includes carrying out actions for motive and social rehabilitation of patients in order that the patient adapted to the defect. Occupations by physiotherapy exercises, trainings of walking, occupation with the logopedist, trainings on a stabilometrichesky platform are recommended.
Sometimes, depending on ataxy type, drug treatment of an inborn cerebellar ataxy using muscle relaxants, nootrop, drugs of anticonvulsant action can be carried out. For treatment of an illness of Pierre Mari the drugs directed to decrease in a tone of muscles (vitamins of group B, Baclofenum, Mellictinum, Condelphinum) are used.