2.1.2. The Purpose: Acquaint the student by subject to neurologies

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МИНИСТЕРСТВО ЗДРАВООХРАНЕНИЯ
РЕСПУБЛИКИ УЗБЕКИСТАН
ТАШКЕНТСКАЯ МЕДИЦИНСКАЯ
АКАДЕМИЯ
КАФЕДРА НЕРВНЫХ БОЛЕЗНЕЙ
MINISTRY OF THE PUBLIC HEALTH OF THE
REPUBLIC UZBEKISTAN
TASHKENT MEDICAL ACADEMY
CHAIR OF THE NERVIOUS DISEASES
Subject to lectures:
INTRODUCTION. THE SHORT HISTORY, ACHIEVEMENTS AND
PROSPECTS TO MODERN NEUROLOGY. CONSTRUCTION AND
FUNCTION OF THE NERVIOUS SYSTEM. THE CLINICAL ANATOMY,
HISTOLOGY AND PHYSIOLOGY SPINAL CORD, THE SPINAL CORD,
SYNDROMES OF THE DEFEAT SPINAL CORD
For student of 5 courses medical and physician-pedagogical faculty
It Is Approved: 25.08.2012
Tashkent 2012
LECTURE 1
Introduction. The Short history, achievements and prospects to modern
neurology. The Clinical anatomy, histology and physiology spinal cord.
Spinal cord, mieloarhitektonika. syndromes of the defeat spinal cord.
2. The purpose:
2.1.2. The Purpose: Acquaint the student by subject to neurologies, about its
importance in medicine, about herits sections, short historian to neurologies,
construction of the nervious system and method of the functional diagnostics. Repeat
the clinical anatomy, histology and physiology spinal cord and study the main
neurological syndromes , appearing under hisits defeat.
3.Problems:
To acquaint students with:
 Introduction in a neurology subject
 History of development of ancient and modern neurology.
 State the history of the development to neurologies. The Scientific heritage
Abu Ali Ibn Sino in the field of neurologies.
 Problems of a subject of neurology.
 The method of functional diagnostics of nervous system.
 Anatomo-functional features of nervous system and it value in statement
topical diagnosis.
 Symptoms and the syndromes arising at defeat spinal cord, peripheral
nervous system.
 Reflexes and reflex activity at a pathology nervous systems.
 The central and peripheral paralyses.
4. Expected results. After listening of lecture the student should know:
• History of development of ancient and modern neurology.
• Problems of a subject of neurology.
• The method of functional diagnostics of nervous system.
• The nervous system and its pathology.
• Anatomo-functional features of nervous system and its value in statement topical
the diagnosis.
• Symptoms and the syndromes arising at defeat spinal cord, peripheral nervous
system.
• Reflexes and reflex activity at a pathology nervous Systems.
• The central and peripheral paralyses
2.1.5. The Contents to lectures.
The subject of nervous disease, to studying exploring clinical manifestations of
the diseases of the nervous system and devisinging methods of their diagnostics,
treatments and preventive maintenances.
The First information about disease of the nervous system meet in written
source of the deep antiquity. In egyptian papyrus beside 3000 years before of the our
era is mentionned palsies, breach to sensitivity. In works Gippokrat, reek, Ibn Sino is
described clinical manifestations of the varied neurological diseases, methods of their
diagnostics and treatments. Already in that time separate conditions were clearly
marked as disease of the cerebrum (the epilepsy, migraine). Gallen (1129 – 1201) - a
prominent physician - has written 400 scientific disquisitions, he produced the
vivisection on ape and has for the first time described the with two upper and two
lower hillocks, having direct attitude, also wandering and others cranial nerves.
D.M..Morganii and T. Villiziy have been able to the certain neurological pons with
corresponding to structure of the brain. The Important contribution to development of
the teaching about morphologies of the nervious system was made Andreem
Vezaliem, Yakob Sylvia, Konstancio Varollii. 18 century are a descriptive period in
development of the neurologist. Appear all new information about separate syndrome
and symptoms and diseases of the nervous system. The methods of the study of the
structure develop In 19 century intensive and functions of the nervous system. The
Development of the physiological direction in study of the nervous system.
I.P.PAVLOV, N.E.VVEDENSKI, A.A.UHTOMSKII and others scientist.
I.M.SECHENOV (1829- 1905) were shown by founder to reflex theory to
psychic activity. He has shown that reflexes - an universal way to reactions of the
brain on the most varied high influences.
I.M.SECHENOV withstood against age of the established belief in that that
functioning(working) the brain will not comply with the law of the material world
and not available to objective study. However prominent suggestion
I.M.SECHENOV about that any manifestations to lifes of the person - a reflexes,
could become the scientific theory only as a result of openings of the concrete forms
to reflex activity of the cerebrum. This problem was solved by I.P. Pavlov (1849 1936) and e about high nervous activity. In Russia shaping to neurologist as separate
discipline is connected with name of A.Y.KOJEVNIKOV (1836 – 1902), which
created first in the world clinic for neurologic patients. The Prominent representative
of the Moscow school neurologist and psychiatrist was S.S.KORSAKOV (1854 –
1900).
V.M.BEHTEREV was one of the prominent scientist 19 age, conducted the
broad studies with using the method of the removing and irritations separate area
brain. Hereunder he contribute; cause big contribution to development of the complex
problem to localizations function in cortex. The Development at the following years
was characterized by the deepened study of the infectious defeats of the nervous
system. There were detailed explored particularities of the clinical current,
mechanisms of the development, methods of the treatment and preventive
maintenances such infectious diseases CNS as tuberculosis meningitis poliomyelitis,
viral encephalitis. The most Further development of the neurological science has
occurred at soviet period.
In histories of medicine Uzbekistan Abu Ali Ibn Sino is one of most great
scientist as Gippokrat and Gallen. In his works is stated enormous actual material, is
described many diseases and ways of their treatment. Ibn Sino has revealled the
general regularities of the operating the human organism, his relationship with
surrounding ambience, is caused - an investigation relations between component
systems- a person - a nature. He considered the organism as unity physical and
psychic as concrete form of the existence to matters. Ibn Sino used the glory of the
connoisseur nervous and psychic diseases. Described Ibn Sino disease and damages
of the nervous system are chosen in determined taxonomic groups Given
categorization of the diseases of the nervous system allows to judge about originality
glance great scientist, has determined resemblance with modern categorization of the
nervious diseases.
The Tempestuous development of medicine begun large scientist of the muddle
ages was prepared in 17 ages amongst which first place occupies Ibn Sinno.
Neurological glances Ibn Sino have got the most further development in scientific
study of the academician AN Ruz, prof..N.M.MADJIDOV, academician AS RUZB,
prof. A.R.RAHIMDJANOV.
In decision of the problems to modern neurology take the active participation
employes neurology chair TMA.
The main function of the nervous system - a regulation of the physiological
processes in organism depending on constantly changing conditions of the external
ambience. The Nervous system realizes the adjustment - an adapting the
organism to external ambience, regulation of all internal processes and their
constancy, for example - temperature of the body, arterial pressure, processes of
the feeding fabric and provision by their oxygen.
The Nervous system consists of central and periphery parts. To central
nervious system consist brain and spinal cord. They morphological and function are
closely bound between it self and without cutting the border go one in another. To
periphery nervous system pertains the cranial nerves and Cerebrospinal nerves,
nervous combinations.
Neurons are the structural and functional building blocks of the nervous
system. This type of cell is specialized for the reception, integration, and
transmission of electrical impulses. Neurons. The cell body (soma) of the neuron is
enclosed by the cell membrane and contains the cell nucleus, mitochondria,
endoplasmic reticulum, neurotubules, and neurofilaments (Fig. 1.1). Dendrites are
short, more or less extensively branched, cellular processes that conduct afferent
impulses toward the cell body. They provide the cell with a much larger surface area
than the cell body alone, thereby increasing the area available for intercellular contact
and for the deployment of cell membrane receptors. Different types of neurons have
different characteristic morphological types of dendrites; those of the cerebellar
Purkinje cells, for example, resemble a deer’s antlers (Fig. 1.2). The axon is a single
cell process, usually longer than a dendrite, which emerges from the cell body at the
axon hillock. It conducts efferent impulses away from the cell body to another neuron
or an effector organ. Generally speaking, every neuron has a soma, an axon, and one
or more dendrites. The structure and configuration of the nerve cell processes
(especially the dendrites) vary depending on the function of the neuron. Thus,
neurons can be classified into a number of morphological subtypes an adequate
supply of nutrients to the neurons and are an important component of the blood−brain
barrier. Other types of supportive cell in the central nervous system include the
oligodendrocytes, microglia, and ependymal cells, and the cells of the choroid
plexus.
Anatomical Fundamentals
The spinal cord is the component of the central nervous system that connects the
brain to the peripheral nerves. It contains:
 in the white matter, fiber pathways leading from the brain to the periphery
and vice versa;
 in the gray matter, an intrinsic neuronal system consisting of:
 interneurons, i. e., relay neurons for the conducting pathways and reflex loops;
 motor neurons in the anterior horns, whose efferent axons travel in the
peripheral nerves;
 somatosensory neurons in the dorsal horns (although many sensory neurons
are located outside the spinal cord, in the spinal ganglia);
 nociceptive sensory neurons in the dorsal horns that receive and transmit
impulses mainly from pain and temperature fibers; and
 autonomic neurons in the lateral horns.
The topographic relations of the spinal cord, vertebral column, and nerve roots are
shown in Fig. 7.1, and the major ascending and descending pathways of the spinal
cord are shown in Fig. 7.2. The blood supply of the spinal cord is described below .
Spinal Cord
Like the brain, the spinal cord is intimately enveloped by the pia mater, which
contains numerous nerves and blood vessels; the pia mater merges with the
endoneurium of the spinal nerve rootlets and also continues below the spinal cord as
the filum terminale internum. The weblike spinal arachnoid membrane contains only
a few capillaries and no nerves. The denticulate ligament runs between the pia mater
and the dura mater and anchors the spinal cord to the dura mater. In lumbar puncture,
cerebrospinal fluid is withdrawn from the space between the arachnoid membrane
and pia mater (spinal subarachnoid space), which communicates with the
subarachnoid space of the brain. The spinal dura mater originates at the edge of the
foramen magnum and descends from it to form a tubular covering around the spinal
cord. Its lumen ends at the S1–S2 level, where it continues as the filum terminale
externum, which attaches to the sacrum, thus anchoring the dura mater inferiorly. The
dura mater forms sleeves around the anterior and posterior spinal nerve roots which
continue distally, together with the arachnoid membrane, to form the epineurium and
perineurium of the spinal nerves.
Spine and Spinal Cord
Unlike the cranial dura mater, the spinal dura mater is not directly apposed to the
periosteum of the surrounding bone (i.e., the vertebral canal) but is separated from it
by the epidural space, which contains fat, loose connective tissue, and valveless
venous plexuses.
The root filaments (rootlets) that come together to form the ventral and dorsal spinal
nerve roots are arranged in longitudinal rows on the lateral surface of the spinal cord
on both sides. The ventral root carries onlymotor fibers, while the dorsal root carries
only sensory fibers. (This socalled “law of Bell and Magendie” is actually not wholly
true; the ventral root is now known to carry a small number of sensory fibers as well.)
The cell bodies of the pseudounipolar sensory neurons are contained in the dorsal
root ganglion, a swelling on the dorsal root just proximal to its junction with the
ventral root to form the segmental spinal nerve.
Dermatomes and Myotomes
The precise region of impaired sensation to light touch and noxious stimuli is an
important clue for the clinical localization of spinal cord and peripheral nerve lesions.
Reflex abnormalities and autonomic dysfunction are further ones, as discussed below.
Dermatomes
A dermatome is defined as the cutaneous area whose sensory innervation is derived
from a single spinal nerve (i.e., dorsal root). The division of the skin into dermatomes
reflects the segmental organization of the spinal cord and its associated nerves. Pain
dermatomes are narrower, and overlap with each other less, than
touch dermatomes; thus, the level of a spinal cord lesion causing sensory impairment
is easier to determine by pinprick testing than by light touch. (The opposite is true of
peripheral nerve lesions.) Radicular pain is pain in the distribution of a spinal nerve
root, i.e., in a dermatome; pseudoradicular pain may occupy a bandlike area but
cannot be assigned to any particular dermatome. Pseudoradicular pain can be caused
by tendomyosis (pain in the muscles that move a particular joint), generalized
tendomyopathy or fibromyalgia, facet syndrome (inflammation of the intervertebral
joints), myelogelosis (persistent muscle spasm resulting from overexertion), and other
conditions. For mnemonic purposes, it is useful to know that the C2 dermatome
begins in front of the ear and ends at the occipital hairline; the T1 dermatome comes
to themidline of the forearm; the T4 dermatome is at the level of the nipples (which,
however, belong to T5); the T10 dermatome includes the navel; the L1 dermatome is
in the groin; and the S1 dermatome is at the outer edge of the foot and heel.
Myotomes
A myotome is defined as the muscular distribution of a single spinal nerve (i.e.,
ventral root), and is thus the muscular analogue of a cutaneous dermatome. Many
muscles are innervated by multiple spinal nerves; only in the paravertebral
musculature of the back (erector spinae muscle) is the myotomal pattern clearly
segmental; the nerve supply here is through the dorsal branches of the spinal nerves.
Knowledge of themyotomes of each spinal nerve, and of the segment-indicating
muscles in particular, enables the clinical and electromyographic localization of
radicular lesions causing motor dysfunction. The segment-indicating muscles are
usually innervated by a single spinal nerve, or by two, though there is anatomic
variation.
Plexuses and Peripheral Nerves
The ventral branches of spinal nerves supplying the limbs join together to form the
cervical (C1– C4), brachial (C5–T1), lumbal (T12–L4), and sacral plexuses (L4–
S4). The brachial plexus begins as three trunks, the upper (derived from the C5 and
C6 roots), middle (C7), and lower (C8, T1). These trunks split into divisions, which
recombine to form the lateral (C5–C7), posterior (C5–C8), and medial (C8 and T1)
cords (named by their relation to the axillary artery). The cords of the brachial plexus
branch into the nerves of the upper limb. The nerves of the anterior portion of the
lower limb are derived from the lumbar plexus, which lies behind and within the
psoas major muscle7); those of the posterior portion of the lower limb from the
sacral plexus. The coccygeal nerve (the last spinal nerve to emerge from the sacral
hiatus) joins with the S3–S5 nerves to form the coccygeal plexus, which innervates
the coccygeus and the skin over the coccyx and anus (mediates the pain of
coccygodynia).
Dermatomes and Myotomes
Brachial Plexus
Nerves of the Upper Limb
Lumbar Plexus
Nerves of the Lower Limb
Spinal Cord and Spinal Nerves
Ascending Tracts
Tracts of the Anterolateral Funiculus
Lateral spinothalamic tract A1. Afferent,
thinly myelinated posterior root fibers
A2 (1. neuron of the sensory tract),
divide in the dorsolateral tract and
terminate in the cells of the substantia
gelatinosa and the posterior horn (2.
neuron). The fibers of the tract arise
from these cells, cross in the commissura alba to the opposite side and
ascend to the thalamus in the lateral
funiculus. This is the pathway for pain
and temperature sensation and ex-teroand proprioceptive impulses. It is
divided somatotopically; the sacral and
lumbar fibers lie dorsolaterally and the
thoracic and cervical fibers lie
ventromedially. Fibers for pain sensation probably lie superficially and those
for temperature sensation more deeply.
The ventral spinothalamic tract A3. The
afferent fibers A4 (1. neuron) divide
into ascending and descending
branches and terminate on posterior
horn cells, whose axons cross to the
opposite side in the anterior funiculus
and ascend toward the thalamus (2. neuron). They transmit crude pressure and touch
sensation. Together with the lateral tract they are considered as the pathway for
protopathlc sensibility.
The spinotectal tract A 5 carries pain fibers to the roof of the midbrain (contraction of
the pupils in pain).
Tracts of the Posterior Funiculus
Fasciculus gracilis (of Goll) C 6 and fasciculus cuneatus (of Burdach) C7. The thick
heavily myelinated fibers ascend in the posterior columns without syn-apsing. They
belong to the first neuron of the sensory tract and terminate on the nerve cells (2.
neuron) of the posterior funicular nuclei. They transmit exteroceptive and
proprioceptive impulses of eplcrttlc sensibility (exteroceptive: information about the
localisation and quality of cutaneous sensibility; proprioceptive: information about
the position of the limbs and body posture). The posterior columns are arranged
somatotopically: the sacral fibers lie medially, toward the lateral side are the lumbar
and thoracic tracts (fasciculus gracilis). Fibers from T1 to C2 lie further laterally and
form the fasciculus cuneatus.
Short descending collaterals C8 leave the ascending fibers. They terminate on
posterior horn cells and form compact bundles - in the cervical cord Schultze s
comma D 9f in the thoracic cord Flechsig s oval field D10 and in the sacral cord the
Phitlipe-Gombault triangle D11.
Cerebellar Tracts of the Lateral Funiculua
Dorsal spinocerebellar tract (Flechsig) B12. The afferent posterior root fibers end
in the cells of the dorsal nucleus (Clarke) B13, from which the tract originates. It runs
to the cerebellum at the margin of the ipsilateral lateral funiculus and carries
principally prop rioceptive impulses from joints, tendons and muscle spindles.
Ventral spinocerebellar tract (Gowers' tract) B14. The cells of origin lie in the posterior
horn. The fibers ascend on the same and on the opposite side at the ventrolateral
margin of the spinal cord to the cerebellum. They carry extero- and proprioceptive
impulses. Both cerebellar tracts are arranged somatotopically: sacral fibers lie dorsally and lumbar and thoracic ones are ventral to them.
The spino-ollvary tract B15 and the splnovestibular tract B16 arise from the
posterior horn cells of the cervical cord and carry mainly proprioceptive impulses to
the interior olive and the vestibular nuclei.
Nerve cells in the spinal ganglion - (1. neuron) ABC 17.
Descending Tracts
Corticospinal Tract, Pyramidal Tract A
The majority of fibers arise in the
pre-central gyrus and the cortex in
front of it {areas 4 and 6), but some
are supposed to come from the
cortical regions of the parietal lobe.
Eighty percent of the fibers cross to
the contralateral side in the lower
medulla oblongata, the pyramidal
decussation A1, and run in the lateral
funiculus as the lateral corticospinal
tract A2. The remainder run
uncrossed
as
the
anterior
corticospinal tract A3 in the anterior
funiculus, and only cross at the level
of their termination. More than half
of pyramidal tract fibers terminate in
the cervical cord to supply the upper
limb, and a quarter end in the
lumbosacral cord to supply the
lower limb. In the lateral funiculus
there is a somatotopic arrangement,
lower limb fibers running on the
periphery and those for the trunk
and the arm lying deeper Most of the
fibers end on interneurons which transmit the impulses for voluntary movement to
anterior horn cells. These fibers not only transmit impulses to the anterior horn cells,
but they also transmit cortical inhibition via interneurons.
Extrapyramidal Tracts B
The extrapyramidal tracts include descending systems from the brain stem which
influence the motor system: the vestibulospinal tract B4 (balance, muscle tonus),
ventral and lateral reticulospinal tract B5 from the pons, lateral reticulospinal tract
B 6 from the medulla oblongata and the tegrnen-tosptnal tract B7 from the midbrain.
The rubrospinal tract B8 (in man largely replaced by the tegmentospi-nal tract) and
the tectospinal tract B9 terminate in the cervical cord and only influence the
differentiated motor activity of the head and upper limb. The medial longitudinal
fasciculus B10 contains various fiber systems of the brain stem.
Vegetative Tracts
The vegetative tracts C consist of poorly myelinated and unmyelinated fibers and
only rarely form compact bundles. The parependymal tract C11 runs on both sides of
the central canal. Its ascending and descending fibers can be followed into the
diencephalon (hypothalamus) and carry impulses for genital function. Ventral to the
pyramidal tract runs the descending tract for vasoconstriction and sweat secretion
(Foerster) C12t which is arranged somatotopically in the same way as the lateral
pyramidal tract.
Representation of the Tracts
The various tracts are not recognisable in transverse section of the normal spinal
cord. Only through experimental lesions (section) and injuries to the spinal cord, or
during development will some of them become visible. The tracts become myelinated
at different times during development, and they stand out from each other because of
this, e.g. the pyramidal tract. D2, which myelinates late. After injury distal fibers
separated from their perikaryon degenerate thus making their area in the cord visible,
e. g. the fas ciculus gracilis E13.
6. The Examples from practical persons.
6.1. At defeat of the front horn or front rootlet appears periphery palsy, atony,
atrophy of the muscles, reduction reflexes.
6.2. At defeat of the front rootlet at a rate of S5-D1 segment - appears periphery palsy
on hand.
6.3. At defeat of the back horns, the rootlet and front sylph of the soldering appear the
segmental of the breach to sensitivity.
The List of the used literature.
1. An introductions to clinical neurology: path physiology, diagnosis and
treatment 1998
2. Parkinsons diseas and Movement Disorders. 1998
3. Neuroscience: Exploring the Brain. 1996
4. Anatomical Science. Gross Anatomy. Embryology. Histology.
Neuroanatomy. 1999
5. Headache. Diagnosis and Treatment. 1993
6. Color Atlas of Human Anatomy Sensory organs And Nervous System
(Werner Kahle) – 1986
7. Color Atlas of Neurology (Thieme 2004)
http://medic.stup.ac.ru/institute/Anatomy/Lection10.htm
http://www.erudition.ru/referat/ref/id.52081_1.html
http://www.medicreferat.com.ru/pageid-58-1.html
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