Medical and social examination and disability in spinal amyotrophies

Definition
Spinal amyotrophies are a group of hereditary diseases caused by a primary dystrophic process in the anterior horns of the spinal cord, manifested by flaccid paresis and muscle atrophy.
They make up about 7% of other motor neuron diseases, which also include amyotrophic lateral sclerosis, the very rare primary lateral sclerosis and progressive bulbar palsy. The prevalence of spinal amyotrophy in the population is from 0.65 to 1.6 per 100,000 population.

Classification
Various clinical forms of spinal amyotrophy differ in the age of onset, rate of progression and type of inheritance of the disease.

The most common forms:
I. Spinal amyotrophies of childhood and adolescence:
1) acute malignant infantile spinal amyotrophy (Werdnig-Hoffmann);
2) chronic infantile spinal amyotrophy;
3) juvenile spinal amyotrophy (Kugelberg-Welander).
II. Spinal amyotrophies in adults:
1) bulbospinal amyotrophy (Kennedy);
2) distal spinal amyotrophy (Duchenne-Arana);
3) scapulo-peroneal amyotrophy (Vulpiana).

Clinic and diagnostic criteria
1. General clinical features: symmetrical weakness of the proximal, less often distal muscles. Asymmetry of damage to the muscles of the extremities and involvement of the bulbar muscle group are relatively rare. As a rule, there are no sensory disorders; pyramidal insufficiency is not typical, although it sometimes occurs at a late stage of the disease.

2.Diagnostic criteria:
- hereditary nature of the disease (the type of inheritance is not always easy to establish);
- muscle atrophy with fasciculations, fibrillations;
- EMG - picture of damage to the anterior horns of the spinal cord;
- absence of sensory and pelvic disorders;
- progressive course;
- fascicular atrophy of muscle fibers on biopsy.

3. Clinical features of individual forms:
1) Werdnig-Hoffmann spinal amyotrophy (malignant infantile spinal amyotrophy) is an autosomal recessive disease, the mutant gene is mapped to the 5th chromosome. Another gene has been identified that provides suppression of apoptosis - programmed death of neurons. It is this gene that is often absent in severely ill patients. The incidence of the disease is 1: 25,000 newborns. Recently, it has been divided into acute (actually the Werdnig-Hoffman form) and chronic infantile spinal amyotrophy.
The acute form manifests itself in the first 5 months of life and ends fatally by 1.5 years. In the chronic form, there is an early childhood form (onset before 1.5-2 years, death by 4-5 years from respiratory failure, pneumonia) and late form (onset before 2 years, immobility by 10 years, death at the age of 15-18 years ). Main symptoms: paresis of the proximal legs, then arms, trunk muscles, respiratory muscles, areflexia, fibrillation, fasciculations of skeletal muscles and tongue, contractures, bone deformities, bulbar symptoms, general hyperhidrosis. EMG shows spontaneous bioelectrical activity at rest with the presence of fasciculation potentials. During voluntary contractions, reduced electrical activity with a “picket fence” rhythm is recorded. The activity of serum enzymes does not change. Pathomorphological examination revealed a decrease in the number of cells in the anterior horns of the spinal cord, in the motor nuclei of the brain stem, and degenerative changes in them. In muscles - fascicular atrophy of muscle fibers;

2) Kugelberg-Welander spinal amyotrophy (juvenile or pseudomyopathic form) - a disease with an autosomal recessive type of inheritance. The type of course and distribution of muscle atrophies are similar to Erb-Roth muscular dystrophy, but there are widespread muscle fasciculations. EMG confirms the spinal nature of muscle atrophy. Pathomorphology of muscles during biopsy, along with neurogenic (fascicular) amyotrophy, reveals signs of primary (diffuse) muscle damage.
The disease begins between the ages of 2 and 15 years and progresses very slowly. Muscle weakness and atrophy develop first in the proximal legs, pelvic girdle and gradually spread to the muscles of the shoulder girdle. Some patients have pseudohypertrophy of muscles, hyperfermentemia (especially an increase in CPK), which brings this form closer to PMD. There are no bone deformities or muscle retractions. Bulbar movement disorders occur at a late stage of the disease. Patients retain the ability to self-care for a long time, and are often able to work for a number of years;

3) Kennedy bulbospinal amyotrophy - an X-linked recessive disease that usually manifests itself after 30 years. It is caused by a specific mutation in the androgen receptor gene, mapped on the X chromosome. Only men get sick. It begins with the proximal parts of the extremities; after 10-20 years (sometimes earlier) bulbar disorders appear in the form of atrophy and weakness of the masticatory muscles, dysphagia, and dysarthria. Due to the very slow progression of the disease, bulbar disorders do not lead to severe impairment of vital functions for many years. There is a tremor of the hands and head, reminiscent of essential tremors. A characteristic symptom is fasciculations in the perioral muscles and tongue and endocrine disorders (gynecomastia, decreased potency, testicular atrophy, diabetes mellitus). The course is slow, the social prognosis is generally favorable;

4) distal spinal amyotrophy of Duchenne-Aran. The mode of inheritance is autosomal dominant or autosomal recessive, sporadic cases are very common. Onset after 20 years (usually at 30-50). The classic form of the disease is characterized by onset in the distal parts of the upper extremities (“clawed hand”), later atrophy spreads to the forearm, shoulder (“skeletal arm”), and after many years weakness of the muscles of the peroneal group and other muscles of the lower leg, thighs, and torso occurs. Mild pyramidal symptoms occur. At the beginning of the process, there may be a one-sided lesion, monoparesis (Mozolevsky Yu. V. et al., 1988). A combination with parkinsonism, torsion dystonia and myoclonic hyperkinesis is possible (Makarov A. Yu., 1967). The disease rarely significantly affects the social status of patients due to its extremely slow progression (except in cases with concomitant pathology);

5) Vulpian scapulo-peroneal form. It begins between 20-40 years with atrophy of the muscles of the shoulder girdle (limited movements in the shoulder joints, “wing-shaped” shoulder blades); over time, weakness of the extensors of the feet and legs is added, although the reverse sequence is possible. The differential diagnosis should primarily be made with Davidenkov's scapuloperoieal myodystrophy. The progression is slow, often elderly patients with 30-40 years of illness are able to move independently.

4. Additional research data:
- EMG, ENMG. With total EMG, signs of an anterior horn lesion: in rest mode, spontaneous bioelectrical activity in the form of fisculation potentials with an amplitude of up to 200 μV, with voluntary contraction, a slowed-down EMG with a “picket fence” rhythm and sharply discharged in severe muscle damage. ENMG shows a decrease in the amplitude of the M-response and the number of functioning motor units. The speed of impulse conduction varies depending on the form of spinal amyotrophy and the age of the patient;
- muscle biopsy (bundle atrophy is typical, as opposed to diffuse atrophy in PMD);
- MRI. Sometimes it helps to detect spinal cord atrophy;
- study of the activity of CPK, LDH, ALT in the blood serum (in contrast to PMD, it is normal or slightly increased);
- medical and genetic counseling.
Differential diagnosis: 1. With PMD that phenocopies spinal amyotrophy (Erb-Roth disease, Davidenkov’s scapuloperoneal myodystrophy, etc.).
2. Acute spinal amyotrophy of Werdnig-Hoffmann - with other causes of the “flaccid child” syndrome (atonic form of cerebral palsy, congenital myopathy, Marfan syndrome, etc.).
3. With amyotrophic lateral sclerosis - Kennedy bulbospinal amyotrophy, other forms of spinal amyotrophy in adults (the final diagnosis is often made after 1-3 years of observation of the patient).
4. With cervical ischemic myelopathy (spinal amyotrophy in adults).
5. With chronic forms of tick-borne encephalitis, Lyme disease.
6. With post-polio syndrome.

Course and prognosis
Depends on the age of onset of the disease. In childhood forms, the outcome is fatal even in the case of a chronic course and the onset of the disease before 2 years. In the case of juvenile Kugelberg-Welander amyotrophy, the ability to self-care remains for many years. In other forms of spinal amyotrophy in adults, life expectancy does not actually change, but increasing motor deficits usually lead to limited life activity and ability to work (many years after the onset of the disease).

Principles of treatment
Hospitalization for initial diagnosis, repeated courses of maintenance therapy (1-2 times a year), in case of decompensation of the disease after injury, infectious disease, etc.
Treatment is based on the same principles as muscular dystrophy - improving the conduction of nerve impulses, correcting energy disturbances in the muscles, improving peripheral circulation. Drugs that stimulate the function of the central nervous system are also used - cerebrolysin, nootropics. Physiotherapy methods are widely used, in particular amplipulse - benzohexonium and proserine phoresis. In some cases, orthopedic correction of contractures and paresis is necessary.

Medical and social examination Criteria of VUT

The indication for VL in working patients (with Kugelberg-Welander amyotrophy, spinal amyotrophy in adults) may be temporary decompensation, a preventive course of treatment in a hospital (duration - 1-2 months).
Characteristics of disability
With rapidly progressing early childhood forms (Werdnig-Hoffman disease), the ability to move and self-care is quickly impaired. In other forms, the ability to move and manipulate (distal form of amyotrophy in adults) and to communicate due to dysarthria (bulbospinal amyotrophy Kennedy) suffers. In the final stages of all forms, the leading criterion for assessing the state of vital activity will be the ability to move and self-care due to widespread paresis and contractures.

Contraindicated types and working conditions
1) All types of intense physical labor, work with a forced body position, with prolonged tension of a certain muscle group, at a prescribed pace (on an assembly line, in a brigade), driving professions; 2) work related to exposure to toxic substances, vibration, radiation, etc.

Indications for referral to BMSE
1.Under the age of 18, when a child, if there are medical indications, can be recognized as disabled.
2. Moderate or severe impairment of motor functions, limiting the ability to move independently, self-care or work.
3. Working patients are unable to continue working in their specialty due to the progressive course of the disease, persistent decompensation, and long-term temporary disability.

able-bodied patients
With a benign, slowly progressive course (especially with dominant forms of inheritance); with mild paresis of the distal part of only the lower or only the upper extremities (spinal amyotrophy of adults); with mild paresis in the proximal lower extremities and pelvic girdle, having education, specialty, work experience, in the absence of factors in their work that negatively affect the course of the disease. When creating the necessary working conditions for such patients, often according to the conclusion of the Institutional Review Board, they can remain able to work for a long time.

Minimum required examination when referring to BMSE
1) Information about the type of inheritance of the disease.
2) EMG, ENMG.
3) Results of pathomorphological examination of muscle biopsy.
4) Results of determining CPK activity in blood serum.

Indications for referral to BMSE
When determined under the age of 18 years: a) partial impairment of life activity and social maladjustment as a manifestation of a hereditary disease (chronic spinal amyotrophy of Werdnig-Hoffmann, amyotrophy of Kugelberg-Welander and other childhood and juvenile forms); b) severe progressive impairment of motor function of the limbs.

When determined after 18 years of age:
Group I: determined in the later stages, with extensive, completed generalization of the atrophic process: lower or upper paraplegia, severe tetraparesis; severe damage to the muscles of the trunk, widespread contractures in large joints of the extremities, since these disorders lead to impairment of the ability to move and self-care of the third degree (usually in the Werdnig-Hoffman form);

Group II: slow progression, but in the stage of beginning generalization of the atrophic process, in the presence of pronounced distal lower paraparesis, its combination with moderate paraparesis of the upper extremities, especially if the process involves the forearms; in the presence of pronounced proximal lower paraparesis and paresis of the pelvic girdle muscles, which leads to a sharp impairment of the ability to walk and stand; with pronounced upper paraparesis - both distal and proximal; in case of addition of even mild bulbar disorders to significantly pronounced (2-3 points) paresis of the legs (according to the criteria of impairment of the ability to move, work activity of the second degree);

Group III: slowly progressing amyotrophies with moderately severe paraparesis of the upper or lower extremities, moderately severe paresis of the proximal lower extremities and pelvic girdle, if these disorders lead to the inability to work in the main profession, and rational employment is impossible, or for the period of vocational training of persons without profession, as well as those forced to acquire a new one (usually in the Kugelberg-Welander form) - according to the criteria of limited ability to independent movement of the first degree and (or) to work of the first degree.

In case of severe impairment of motor functions and the futility of rehabilitation measures, disability is established indefinitely (after no more than 4 years of observation of the patient).

Causes of disability: 1) disability since childhood (in the Kugelberg-Welander form); 2) a general disease or a disease acquired during military service (with spinal amyotrophy in adults).
Corresponds to what is carried out in relation to patients with PMD. For forms with a known gene locus, prenatal diagnosis is possible in the initial period of pregnancy. In the case of Kugelberg-Welander amyotrophy, disability prevention is often facilitated by early career guidance and education of patients; in spinal amyotrophy of adults, rational employment, sometimes after acquiring a new profession.

Rehabilitation
An individual program is developed for patients with Kugelberg-Welander disease and adult spinal amyotrophies.
1.Medical rehabilitation consists of repeated courses of drug therapy, massage, physical therapy, sanatorium treatment, supply of orthopedic shoes, fixation devices, a bed and a mattress of a special design. Its psychological aspect includes organizing education for disabled children at home, guiding the patient and his parents toward adequate employment, and organizing the child’s life in the family.
2.Vocational rehabilitation:
a) vocational training in technical schools (lyceums, colleges), vocational rehabilitation centers for patients with Kugelberg-Welander amyotrophy and spinal amyotrophy in adults. Recommended specialties: accounting, office management, marketing, jurisprudence and accounting in the social security system, standardization technologist, radio mechanic for repair of stationary radio and television equipment, shoemaker for shoe repair, watchmaker, bookbinder, etc.;
b) employment of disabled people of group III. Depending on the predominant localization and severity of muscle atrophy, the following work may be recommended:
- mental labor: economist, planner, engineer, process technician, lawyer, translator, statistician, bibliographer, librarian;
- accounting, clerical and administrative work: accountant, standard setter, accountant, merchandiser, HR department inspector, dormitory commandant, etc.;
- light and moderate physical labor (for patients with leg paresis): fitter-assembler of small-sized products, repairman of radio and television equipment in the workshop, bookbinder;
- work in mass household professions (with damage to the upper or lower extremities): watchman, timekeeper, dispatcher at a stationary workplace, kiosk operator.

Labor recommendations should provide for the optimal nature of work, requiring light physical and neuropsychic stress in comfortable or close to comfortable conditions (severity category I - one-time heavy lifting of no more than 2 kt, physical activity per shift - 900 kcal).

c) disabled people of group II (amyotrophy of adults and Kugelberg-Welander disease) can be employed at home in their main specialty (highly qualified mental workers), as well as as a bookbinder, gluer, assembler of small parts, knitter.

3. Social rehabilitation: providing patients with special devices for using the bathroom, toilet, and wheelchair. Due to the progressive course of the disease, driving is contraindicated for the patient.

A genetic disease is a pathological condition, the occurrence of which is caused by mutational changes in genes. Ailments of this type are inherited and most often make themselves felt in early childhood. According to statistics, in the modern world, more than 5 million children a year are born with genetic disorders, due to the progression of which many of the children do not even live to be 5 years old. Thus, today it has been established that about 40-50% of early childhood mortality is due to hereditary mutations, which include Kugelberg-Welander amyotrophy.

Kugelberg-Welander amyotrophy is a hereditary neurological disease that damages the motor neurons of the spinal cord. This pathology is classified as juvenile spinal amyotrophy type III. The first signs of Kugelberg-Welander amyotrophy usually appear between the ages of 2 and 15 years.

Compared with spinal amyotrophy of the infantile and intermediate type, this disease has a more favorable prognosis - the life expectancy of patients suffering from Kugelberg-Welander amyotrophy corresponds to the average mortality rates among healthy people.

Causes

The development of Kugelberg-Welander amyotrophy is activated due to a mutation in the so-called motor neuron survival gene (SMN1), located on chromosome 5 and responsible for the production of a special protein, deficiency of which leads to the death of motor nerve cells.

To date, it has been revealed that approximately 1 in 40 people are carriers of this DNA mutation. Due to the fact that spinal amyotrophy is a pathology with an autosomal recessive type of inheritance, its activation is possible only if both parents have the same mutated gene. Thus, the probability of developing Kugelberg-Welander amyotrophy in a child is no more than 25%.

Specifics

As a rule, the first symptoms of Kugelberg-Welander amyotrophy begin to appear at the age of 2, and at a later age this disease makes itself felt extremely rarely.

Due to the fact that muscle weakness in type III spinal amyotrophy develops rather slowly, the ability for independent movement and self-care in patients suffering from this pathology is preserved for quite a long time.

As a rule, people diagnosed with Kugelberg-Welander amyotrophy are assigned a disability group, the level of which is determined according to the severity of motor impairment, disability and dependence on other persons.

It is extremely difficult to predict exactly how this disease will affect the child’s condition. Thus, some patients become deeply disabled even in adolescence, and some are able to retain well-developed coordination abilities even at 40 years of age.

Symptoms

Kugelberg-Welander amyotrophy primarily manifests itself through increasing muscle weakness in the legs, which may cause the child to have a waddling gait. In addition, a child suffering from spinal amyotrophy, even after a short walk and running short distances, complains of fatigue. A child with this disease often falls, loses balance, and has great difficulty climbing stairs. Appearing initially in the muscles of the legs and pelvis, the feeling of weakness gradually moves to the muscle tissue of the shoulder and elbow areas.

As this disease progresses, motor depression develops in the facial muscles. In addition, tendon reflexes disappear, and involuntary contraction of the arm muscles occurs.

Symptoms indicating activation of Kugelberg-Welander amyotrophy also include tongue spasms and decreased range of motion of the shoulder and elbow joints. As a result of atrophy of the muscles of the shoulder girdle, patients gradually develop winged blade syndrome.

In many cases, children suffering from this disease experience false hypertrophy of the muscles of the calves and buttocks, which is formed by replacing muscle tissue with fatty and connective tissue.

As Kugelberg-Welander amyotrophy progresses, deformation changes in the bone structures of the musculoskeletal system may also occur, including curvature of the spine, deformation of the chest and feet.

In the later stages of development of Kugelberg-Welander amyotrophy, respiratory failure usually develops, causing swelling of the airways and shortness of breath, which gradually turns into suffocation. The lack of emergency medical care for such a pathological condition is fraught with death.

Diagnostics

It is possible to clarify the diagnosis in case of suspected activation of Kugelberg-Welander amyotrophy through DNA testing. Electroneuromyography is also prescribed as an additional diagnostic procedure, with the help of which muscle tension is monitored, the level of activity of motor neurons is assessed, and the presence of denervation changes is determined. In addition, if necessary, a skeletal muscle biopsy may be performed.

Treatment

For patients suffering from Kugelberg-Welander amyotrophy, exclusively symptomatic treatment is indicated, within which a special therapeutic course is developed aimed at mitigating the symptomatic manifestations of this disease. First of all, patients with this diagnosis are prescribed nootropic drugs, anabolic steroids and vitamin complexes.

Effective methods of alleviating the condition of patients of this profile also include therapeutic exercises and restorative massage. In addition, orthopedic correction may be recommended for a patient who has severe bone deformities.

Spinal amyotrophy Kugelberg-Welander

Another name for this disease is benign spinal amyotrophy of childhood and adolescence with fasciculations. The type of inheritance is autosomal recessive. The first symptoms of the disease can appear in early childhood, but most often at 8-12 years of age. Characterized by atrophy of the muscles of the proximal limbs, fibrillary and fascicular twitching. Muscle hypertrophy and retardation in physical and mental development are often observed.

Neural amyotrophy of Charcot-Marie-Tooth

It is inherited in an autosomal dominant manner and begins most often at the age of 20-30 years, less often at school age and has subtypes 1a and 16. The gene is mapped to the long arm of chromosome 5. Positional cloning revealed a disease locus on chromosome 17p11.2 (type 1a) and a smaller locus on chromosome Ig22 (type 16).

Pathomorphologically, neural amyotrophy is characterized by degenerative changes in the anterior horns and posterior columns of the spinal cord, as well as in the roots and peripheral nerves.

Clinical manifestations. Atrophic changes in the muscles of the distal extremities, most often the lower ones, predominate. The extensors of the lower leg, as well as the dorsal flexors of the foot, are affected, as a result of which the feet begin to sag. The patient walks, raising his knees high (steppage), and a valgus position of the feet develops (outward rotation). Tendon reflexes, most often Achilles, fade away. There is some discrepancy between significant muscle atrophy and preservation of motor functions; in most cases, distal sensory disorders of the “gloves” and “socks” type are noted. Pain and paresthesia may appear, as well as a decrease in deep sensitivity due to damage to the posterior columns of the spinal cord. Deformation of the feet is often detected: they become hollow with a high arch, extension of the main and flexion of the terminal phalanges. The course of the disease is slowly progressive.

This disease occurs in early childhood and is characterized by a malignant course with rapid progression. Depending on the time of appearance of the first symptoms and the rate of growth of the process, three forms of the disease are distinguished: congenital, early childhood and late.
Congenital form may appear in the prenatal period. In such cases, fetal movement, which was normal at first, becomes weak in the later stages of pregnancy, childbirth can be pathological, and already in the first days after the birth of the child, obvious muscle paresis is detected with a decrease in muscle tone and a decrease in tendon reflexes. Sometimes complete areflexia is noted. Early bulbar symptoms may occur, manifested by weak crying and sluggish sucking. In a child, fibrillations in the tongue, decreased pharyngeal reflex, and hypomimia can be detected. Tachycardia is usually observed. The disease is often combined with a number of developmental defects and mental retardation. The course of the disease is very rapid, death occurs by 1-l.5 years.
Early childhood form characterized by a slightly milder course compared to congenital. This form is considered classic. The onset of the disease occurs before the age of 1.5 years. In most cases, the first symptoms appear after some kind of infection or food intoxication. The child, who had previously developed more or less normally, quickly loses previously acquired motor skills and stops walking, standing or sitting. Flaccid paresis first occurs in the legs, then in the muscles of the torso and arms. The condition deteriorates relatively quickly, weakness appears in the neck muscles and bulbar muscles. By 4-5 years, usually as a result of respiratory failure, pneumonia develops and death occurs. In patients, flaccid paresis is accompanied by the development of tendon contractures. General hyperhidrosis is often observed.
Late form begins after the age of 1.5-2 years and flows easily compared to the first two forms. Patients up to 10 years of age can retain the ability to move.
The leading symptoms are paresis in the proximal parts of the legs, then the arms. Muscle atrophy is difficult to detect due to the well-defined subcutaneous fat layer. Tendon reflexes fade early. Characteristic is a fine tremor of the fingers of outstretched arms (fascicular tremor). Bone deformities are typical, especially in the chest, but also in the lower extremities. Bulbar symptoms are represented by atrophy of the tongue muscles with fibrillary twitching, paresis of the soft palate with a decrease in the pharyngeal reflex.
A special variant of Werdnig-Hoffmann spinal atrophy is known - progressive palsy or Fazio-Londe disease. The disease most often begins at the end of the second year of life, sometimes in juvenile age, and is characterized by weakness in the facial muscles, including the masticatory muscles, difficulty swallowing, changes in voice, and atrophy in the muscles of the tongue. Ophthalmoplegia may occur. The disease progresses rapidly, and death occurs 6-12 months after the onset of the first symptoms. Bulbar disorders can be accompanied by flaccid paresis and paralysis of the limbs; sometimes they do not have time to develop, but at autopsy, damage to the cells of the anterior horns of the spinal cord is constantly detected throughout its entire length. Family cases of Fazio-Londe disease have been described, when one or more siblings suffered. The type of hereditary transmission is autosomal recessive.
Diagnosis of spinal amyotrophy of Werdnig-Hoffmann is based (in addition to the early onset of the disease and the characteristic clinical picture) on the results of additional research methods, of which electromyography should be pointed out first. Spontaneous bioelectrical activity at rest with the presence of fasciculation potentials is almost always detected. During voluntary contractions, slower electrical activity with a “picket fence rhythm” is recorded, which indicates synchronization phenomena and an increase in the duration of the potential.
Pathomorphological examination reveals a decrease in the number of cells in the anterior horns of the spinal cord and degenerative changes in them. Pathological changes are especially pronounced in the area of ​​the lumbar and cervical enlargements, as well as in the motor nuclei of the cranial nerves. Changes are detected in the anterior roots and in the intramuscular sections of the nerve endings. In the latter, normal terminals disappear and become excessively branched.
Biochemical studies reveal changes in carbohydrate metabolism. Thus, E. A. Savelyeva-Vasilieva (1973) discovered that glycolysis in patients with Werdnig-Hoffmann spinal amyotrophy approaches the embryonic type. Quite often, significant disturbances in creatine-creatinine metabolism are detected - increased excretion of creatine in the urine, decreased excretion of creatinine. It is important to note that the level of enzymes in the blood serum remains almost unchanged.
Spinal amyotrophy Werdnig-Hoffmann refers to hereditary diseases with an autosomal recessive type of transmission. The primary biochemical defect is unknown. There is an assumption that the genetic defect leads to defective formation of cells of the anterior horns of the spinal cord, disruption of their differentiation and possible underdevelopment of muscle cholinergic receptors.
When diagnosing Werdnig-Hoffmann spinal amyotrophy, differentiation is made with Oppenheim myotonia. According to most researchers, Oppenheim myotopia is not an independent nosological entity, but a syndrome, the leading manifestation of which is pronounced muscle hypotonia. In this regard, the term “floppy baby” or “flaccid child” has now become widespread. The “flaccid child” syndrome is observed in diseases such as congenital muscular dystrophy, a benign form of congenital hypotonia, rickets, the atonic form of cerebral palsy, as well as transverse spinal cord injury, acute polio in utero, or polyradiculoneuritis. “Floppy baby” syndrome can occur with universal muscular hypoplasia (Krabbe disease), with glycogenosis, in particular with type II - or Pompe disease (universal glycogenosis).
Treatment for Werdnig-Hoffmann spinal amyotrophy, it comes down to prescribing massage and exercise therapy, which should be carried out systematically. There is no radical treatment available.
Some improvement is provided by drugs such as Cerebrolysin, aminalon, anticholinesterase drugs (proserin, oxazil, galantamine, sanguinarine), B vitamins. Repeated transfusion of small doses of same-group blood (50 ml 4-5 times) is considered as a general strengthening agent and is indicated in pronounced stages of the disease.

Pseudomyopathic form of progressive spinal amyotrophy Kugelberg-Welander

In 1942, Wohlfart first described a disease manifested by muscle atrophies and paresis and resembling primary muscular dystrophy, but with widespread fasciculations. In 1956, Kugelberg and Welander emphasized that such a disease is relatively benign; careful electromyographic monitoring allowed the authors to clarify the neurogenic nature of muscle atrophy and classify the latter as a spinal lesion.
The disease begins in most cases at the age of 3-6 years and progresses very slowly. Cases of later appearance of the first symptoms, including in adults, have also been described. Patients retain the ability to self-care for a long time and even sometimes work. According to clinical symptoms, the disease resembles the limb-girdle form (Erb's muscular dystrophy). Muscle weakness and atrophy develop first in the proximal parts of the lower extremities and the pelvic girdle, then spread to the shoulder girdle. The similarity with Erb's muscular dystrophy is reinforced by the presence of pseudohypertrophy of the gastrocnemius muscles in a significant number of cases. Bone deformities and tendon retractions are usually absent. With Kugelberg-Welander amyotrophy, the process can spread to the bulbar region, which is clinically manifested by slight hypotrophy of the tongue and fibrillary twitching. The latter can also be observed in the facial muscles. Motor disorders, as manifestations of nuclear damage to the X-IX-XII and VII pairs of cranial nerves, are detected very late, only at an advanced stage of the pathological process.
Additional studies in Kugelberg-Welander spinal amyotrophy reveal rather peculiar changes - electromyography indicates clear signs of spinal damage, at the same time, the pathomorphological picture during muscle biopsy is represented by a mixed nature of the pathology - along with neurogenic amyotrophy, there are indications of some dystrophic signs. Similar data are obtained from biochemical studies - the activity of enzymes, including creatine phosphokinase, is often increased, although to a lesser extent than with true myopathy. The indicators of creatine-creatinine metabolism change.
Kugelberg-Welander spinal amyotrophy is a hereditary disease with an autosomal recessive type of transmission and, apparently, with incomplete penetrability, since sporadic cases are very common. There are some descriptions of autosomal dominant inheritance of the disease. Until now, not all authors consider Kugelberg-Welandeoa amyotrophy as an independent disease, considering it only a “mild” variant of Werdnig-Hoffmann disease. The main argument in favor of this statement is the observation in one family of siblings with both forms of spinal amyotrophy. However, the presence of symptoms such as muscle pseudohypertrophy, hyperfermentemia, and a particularly mild course testifies to the nosological independence of Kugelberg-Welander amyotrophy. From a practical point of view, this is important, since there is a different prognosis for the two forms of spinal amyotrophy.
There is no specific treatment for Kugelberg-Welander amyotrophy. Symptomatic and restorative agents are used. The correct choice of profession and the elimination of physical overload are important.

Neurogenic glenohumeral-facial syndrome (spinal variant of Landouzi-Dejerine myopathy)

In some cases, with spinal amyotrophy, the localization of atrophies is characteristic of Landouzi-Dejerine myodystrophy, i.e. it concerns mainly the muscles of the shoulder girdle, especially the fixing scapulae, the proximal parts of the upper limbs (biceps and triceps brachii muscles) and the facial muscles. An electromyographic study reveals high-amplitude, reduced bioelectrical activity with clear fasciculations potentials, i.e., a picture characteristic of the spinal level of the lesion. The activity of enzymes in the blood serum in such patients is usually normal, the indicators of creatine-creatinine metabolism are almost unchanged. Currently, many descriptions of similar cases have accumulated in the literature, and a number of authors identify neurogenic muscular atrophy, reminiscent of the Landouzy-Dejerine form.
The onset of the disease, as with Landouzy-Dejerine myodystrophy, occurs at different ages - both in childhood and in adulthood (from 7 to 40 years). The disease has a relatively benign course and progression is slow. In the spinal variant of Landouzi-Dejerine disease, the asymmetry of the lesion is more clearly revealed. Cardiac changes documented by ECG abnormalities are relatively common, in contrast to glenohumeral muscular dystrophy. Damage to the facial muscles may be minimal or detected late.
Some authors consider the scapular-peroneal form of amyotrophy as a type of neurogenic variant of Landouzi-Dejerine myodystrophy. In these cases, involvement of the heart in the pathological process is sometimes described.

Rare forms of spinal muscular atrophy

Rare forms of spinal amyotrophy include hereditary distal muscular atrophy. The disease begins in the distal parts of the lower extremities, the distal parts of the arms are gradually involved in the process, and generalization of the process can be observed.
A neurogenic form of oculopharyngeal atrophy, transmitted in an autosomal dominant manner, has been described. The authors reported a case where autopsy revealed degeneration of cells in the anterior horns of the spinal cord and motor nuclei of the cranial nerves, including nuclei III and X pairs.
Spinal amyotrophies include most cases of multiple congenital arthrogrypposis. The pathological process consists of underdevelopment of the cells of the anterior horns of the spinal cord with paresis of the corresponding muscles. As a result of uneven muscle traction in utero, contractures and abnormal development of joints can form. During biopsy and EMG studies, in some cases, neurogenic and myogenic changes are noted, and therefore the term “pseudomyopathy” was proposed.
There are also undifferentiated forms of spinal amyotrophy with a rapidly progressive, slowly progressive and non-progressive course.

Amyotrophy - violation of muscle trophism due to damage to peripheral motor neurons, accompanied by their degenerative-dystrophic changes, thinning and impaired contractile function. Among spinal A., Werdnig-Hoffmann disease, the pseudomyopathic progressive form of Kugelberg-Welander, Aran-Duchenne disease are distinguished. Clinical manifestations are the gradual development of flaccid paralysis and muscle atrophy, asymmetry of the lesion, and the absence of tendon reflexes. The sensitivity and functions of the pelvic organs are usually not impaired. A qualitative reaction of degeneration is noted when studying electrical excitability. Spinal amyotrophy Werdnig-Hoffmann . Autosomal recessive disease. Distinguish congenital, early childhood and late forms of the disease. The congenital form can manifest itself in the prenatal period (late and sluggish fetal movements are noted) or in the first months of the child’s life. The child is born with flaccid paresis, generalized muscle hypotonia, and absence of tendon reflexes. Only a few children develop the ability to hold their head up and sit up independently. The course is rapidly progressing. The main cause of death is respiratory and cardiovascular failure due to weakness of the respiratory muscles and bulbar disorders.

The late form begins gradually at the age of 1.5-2.5 years. The child's movements and gait become uncertain, and children often fall. Flaccid paresis and atrophy of the muscles of the proximal limbs appear. Tendon reflexes are reduced. Muscular hypotonia contributes to the development of chest deformities and joint laxity. Fibrillation of the tongue muscles and decreased pharyngeal and palatal reflexes are typical. Bulbar syndrome with dysphagia gradually develops. With this form of A., patients live up to 20-30 years.

Diagnosis is made based on clinical data.

Treatment. Exercise therapy, massage, and drugs that improve the trophism of nervous tissue are prescribed - cerebrolysin, aminalon, pyriditol.

Spinal amyotrophy Kugelberg - Welander autosomal recessive or autosomal dominant disease begins in most cases in aged 4-8 years, sometimes later. Fatigue, general weakness, weakness in the legs (especially when climbing stairs), and fascicular twitching in the muscles appear. Muscle atrophy gradually develops, which can be masked by the deposition of subcutaneous fat. The gait changes, muscle tone decreases, tendon reflexes disappear, and the range of active movements decreases (flaccid paresis). On examination, the so-called pseudohypertrophy of the calf muscles is noted (an increase in their volume due to the development of adipose tissue). A few years after the manifestation of A. in the lower extremities, atrophy and fascicular twitching appear in the proximal muscle groups of the upper extremities (ascending type A.). The course is slowly progressive, motor activity persists for a long time. Patients live up to 40-50 years, often having the ability to self-care. When bulbar symptoms appear in the later stages, the prognosis worsens.

Diagnostics based on the clinic, the results of global and needle electromyography and a morphological study of skeletal muscles, which allows us to identify the denervation nature of the changes.

Adult spinal amyotrophy (Aran-Duchenne disease) . The belonging of this disease to spinal A. is not recognized by all researchers. The disease begins at the age of 40-60 years. Symmetrical progressive atrophy of the muscles of the distal limbs (usually the hands) gradually develops. Subsequently, the muscles of the proximal limbs, pelvic and shoulder girdles are also involved in the process. There are fasciculations in the affected muscles, and fibrillations in the muscles of the tongue. The course is slowly progressive. Death usually occurs from bronchopneumonia.