Sagittal size of the spinal canal. Spinal cord Sagittal size of the spinal canal normal lumbar

2) 1 cm; 4) 3 cm.

1. 
   How many deep longitudinal grooves are there on the surface? spinal cord?

1. 
   Where is the so-called gray matter of the brain located primarily in the spinal cord?

4) throughout the periphery.

1. 
   Directly connected to the spinal cord are structures that are numerous processes of motor neurons covered with a connective tissue membrane. What is the term for one such structure?

2) posterior root.

1. 
   Name the type of nerve cell processes that make up motor neurons.

2) dendrites only;

3) axons and dendrites.

1. 
   During the implementation of the reflex, excitation usually moves through several structures located sequentially. Which of these structures is located last along the direction of excitation movement at the moment of the reflex?

2) working body;

3) motor neuron;

4) receptor;

5) interneuron.

1. 
   In the cervical, lumbar and sacral parts of the spinal cord, the gray matter in a transverse section has characteristic shape. Name it.

2) cross; 5) oval (ellipse);

3) butterfly; 6) dragonfly.

1. 
   What happens to reflex reactions when braking? nerve cells that reflex arc that ensures the implementation of these reflex reactions?

2) intensify;

3) do not arise, weaken or stop.

1. 
   A typical reflex arc contains three types of neurons. Which of these neurons is located first along the movement of excitation along the reflex arc?

2) sensitive;

3) insertion.

1. 
   In some diseases, the conduction of excitation from the brain to the spinal cord is disrupted, but in reverse direction the excitement is normal. Indicate a phenomenon that will NOT occur in such diseases.

2) knee reflex;

3) unconditioned urination reflex;

4) a pricking sensation in the skin of the hand.

Spinal cord.

Option 2.

1. 
   Name the structure that is formed by the arches of the vertebrae of the spine.

3) spinal canal;

4) spinal membrane;

5) spinal column.

1. 
   How many pairs of spinal nerves arise from the spinal cord?

2) 10; 4) 20; 6) 31;

1. 
   Name the direction in which excitation goes along most of the nerves of the anterior roots of the spinal cord.

2) to the spinal cord.

1. 
   During the implementation of the reflex, excitation usually moves through several structures located sequentially. Which of these structures is located first along the direction of excitation at the moment of the reflex?

2) working body;

3) motor neuron;

4) receptor;

5) interneuron.

1. 
   In a cross-section of the spinal cord, the gray matter has the appearance of outstretched “butterfly wings.” These "wings" are called the spinal cord horns. Name those areas of the gray matter of the spinal cord where motor (executive) neurons are located.

2) rear horns.

1. 
   Name the term that is used to describe the initial portion of the spinal nerves, which is located near the spinal cord.

2) dendrite; 5) trunk.

3) leg;

1. 
   The area of ​​the dorsal roots, located immediately next to the spinal cord, consists mainly of the processes of neurons of one type. Name this type of nerve cell processes.

1. 
   What term refers to the function performed directly by the white matter of the spinal cord?

2) conductor; 4) motor.

1. 
   The spinal cord performs several functions. Find these functions among the answers and indicate the function that the spinal cord does NOT perform.

2) sensitive;

3) conductor.

1. 
   Indicate the neurons located outside the central nervous system.

2) motor;

3) insert.

Spinal cord.

Option 3.

1. 
   Name the term used to describe the hollow structure located in the center of the spinal cord.

2) spinal (central) canal;

3) spinal canal;

4) roots.

1. 
   The spinal cord has a segmental structure. How many segments are there in the spinal cord?

1. 
   Directly connected to the spinal cord are structures that are numerous processes of sensory neurons, which, together with the bodies of the sensory neurons themselves, are covered with a connective tissue membrane. What is the term for one such structure?

2) posterior root.

1. 
   Name the type of nerve cell processes that make up the mixed nerves.

2) dendrites only;

3) axons and dendrites.

1. 
   During the implementation of the reflex, excitation usually moves through several structures located sequentially. Which of these structures is located second in the direction of excitation movement at the moment of the reflex?

2) working body;

3) motor neuron;

4) receptor;

5) interneuron.

1. 
   When viewed through a cross section of the spinal cord, which major component of the central nervous system looks like the letter “H” or the spread wings of a butterfly?

2) white matter.

1. 
   What happens to reflex reactions when the nerve cells of the reflex arc that ensures the implementation of these reflex reactions are excited?

2) do not arise;

3) appear or intensify.

1. 
   Spinal nerves arise from the spinal cord, starting with the so-called roots. How many such roots does each spinal nerve have?

1. 
   What is the name of that part of the spinal cord and brain, the main component of which is the bodies of nerve cells?

1. 
   On which side of the surface of the spinal cord are the deep longitudinal grooves located?

2) only on the back;

3) only on the sides;

4) only on the front and rear;

5) on the front, back and sides.

Spinal cord.

Option 4.

1. 
   Where in the spinal cord is the so-called white matter of the brain primarily located?

2) only on the sides of the central part;

3) only in front and behind the central part;

4) throughout the periphery.

1. 
   Name the structure in which the spinal cord is located.

2) spinal (central) canal;

3) joint capsule;

4) ventricles of the brain.

1. 
   Name the direction in which excitation goes along most of the nerves of the dorsal roots of the spinal cord.

2) to the spinal cord.

1. 
   During the implementation of the reflex, excitation usually moves through several structures located sequentially. Which of these structures is located fourth in the direction of excitation movement at the moment of the reflex?

2) working body;

3) motor neuron;

4) receptor;

5) interneuron.

1. 
   The spinal nodes are located in a specific area of ​​the human body. Name this area.

2) white matter of the spinal cord;

3) dorsal roots of the spinal cord;

4) anterior roots of the spinal cord;

5) membrane of the spinal cord.

1. 
   The anterior roots of the spinal cord consist mainly of processes of neurons of one type. Name this type of nerve cell processes.

1. 
   What type of nerves are spinal nerves?

2) sensitive;

3) mixed.

1. 
   What is the name of that part of the spinal cord that is located in its central section and in a cross section looks like the spread wings of a butterfly?

1. 
   The arc of the knee extensor reflex includes two types of neurons. Find these neurons among the answers and indicate the type of neurons missing in the reflex arc of this reflex.

2) motor;

3) insert.

1. 
   The bodies of sensory neurons are located in the spinal ganglia. Indicate the process of these neurons along which excitation moves from the spinal ganglion to the spinal cord.

2) dendrite only;

3) axon and dendrite.

Answers to the Spinal Cord Test.

The spinal cord is the part of the central nervous system located in the spinal canal. The conventional boundary between the medulla oblongata and the spinal cord is considered to be the place of decussion and origin of the first cervical root.

The spinal cord, like the brain, is covered with meninges (see).

Anatomy (structure). Along its length, the spinal cord is divided into 5 sections, or parts: cervical, thoracic, lumbar, sacral and coccygeal. The spinal cord has two thickenings: the cervical, associated with the innervation of the arms, and the lumbar, associated with the innervation of the legs.

Rice. 1. Cross section of the thoracic spinal cord: 1 - posterior median sulcus; 2 - posterior horn; 3 - side horn; 4 - front horn; 5-central channel; 6 - anterior median fissure; 7 - anterior cord; 8 - lateral cord; 9 - posterior cord.

Rice. 2. Location of the spinal cord in the spinal canal (cross-section) and exit of the spinal nerve roots: 1 - spinal cord; 2 - posterior root; 3 - anterior root; 4 - spinal node; 5 - spinal nerve; 6 - vertebral body.

Rice. 3. Diagram of the location of the spinal cord in the spinal canal (longitudinal section) and the exit of the spinal nerve roots: A - cervical; B - breast; B - lumbar; G - sacral; D - coccygeal.

The spinal cord is divided into gray and white matter. Gray matter is a collection of nerve cells to which nerve fibers approach and depart. In a cross section, the gray matter has the appearance of a butterfly. In the center of the gray matter of the spinal cord is the central canal of the spinal cord, barely visible to the naked eye. In the gray matter, there are anterior, posterior, and in the thoracic region, lateral horns (Fig. 1). To sensitive cells posterior horns the processes of the cells of the spinal ganglia, which make up the dorsal roots, are suitable; The anterior roots of the spinal cord extend from the motor cells of the anterior horns. Cells of the lateral horns belong to (see) and provide sympathetic innervation internal organs, vessels, glands, and cell groups of gray matter sacral region- parasympathetic innervation of the pelvic organs. The processes of the cells of the lateral horns are part of the anterior roots.

The roots of the spinal cord exit the spinal canal through the intervertebral foramina of their vertebrae, going from top to bottom over a more or less significant distance. They make a particularly long journey in the lower part of the vertebral column, forming the cauda equina (lumbar, sacral and coccygeal roots). The anterior and posterior roots come close to each other, forming the spinal nerve (Fig. 2). A section of the spinal cord with two pairs of roots is called a spinal cord segment. In total, 31 pairs of anterior (motor, ending in the muscles) and 31 pairs of sensory (coming from the spinal ganglia) roots depart from the spinal cord. There are eight cervical, twelve thoracic, five lumbar, five sacral segments and one coccygeal. The spinal cord ends at level I - II lumbar vertebra, therefore, the level of location of the spinal cord segments does not correspond to the vertebrae of the same name (Fig. 3).

White matter is located along the periphery of the spinal cord, consists of nerve fibers collected in bundles - these are descending and ascending pathways; distinguish between anterior, posterior and lateral funiculi.

The spinal cord is relatively longer than that of an adult, and reaches the third lumbar vertebra. Subsequently, the spinal cord lags somewhat behind its growth, and therefore its lower end moves upward. The spinal canal of a newborn is large in relation to the spinal cord, but by 5-6 years the ratio of the spinal cord to the spinal canal becomes the same as in an adult. Growth of the spinal cord continues until approximately 20 years of age, and the weight of the spinal cord increases approximately 8 times compared to the neonatal period.

The blood supply to the spinal cord is carried out by the anterior and posterior spinal arteries and spinal branches arising from the segmental branches of the descending aorta (intercostal and lumbar arteries).

Rice. 1-6. Cross sections of the spinal cord at various levels (semi-schematic). Rice. 1. Transition of the 1st cervical segment into medulla. Rice. 2. I cervical segment. Rice. 3. VII cervical segment. Rice. 4. X thoracic segment. Rice. 5. III lumbar segment. Rice. 6. I sacral segment.

Ascending (blue) and descending (red) pathways and their further connections: 1 - tractus corticospinalis ant.; 2 and 3 - tractus corticospinalis lat. (fibers after decussatio pyramidum); 4 - nucleus fasciculi gracilis (Gaull); 5, 6 and 8 - motor nuclei of cranial nerves; 7 - lemniscus medlalis; 9 - tractus corticospinalis; 10 - tractus corticonuclearis; 11 - capsule interna; 12 and 19 - pyramidal cells of the lower parts of the precentral gyrus; 13 - nucleus lentiformis; 14 - fasciculus thalamocorticalis; 15 - corpus callosum; 16 - nucleus caudatus; 17 - ventrulculus tertius; 18 - nucleus ventrals thalami; 20 - nucleus lat. thalami; 21 - crossed fibers of tractus corticonuclearis; 22 - tractus nucleothalamlcus; 23 - tractus bulbothalamicus; 24 - nodes of the brain stem; 25 - sensitive peripheral fibers of the trunk nodes; 26 - sensitive nuclei of the trunk; 27 - tractus bulbocerebellaris; 28 - nucleus fasciculi cuneati; 29 - fasciculus cuneatus; 30 - ganglion splnale; 31 - peripheral sensory fibers of the spinal cord; 32 - fasciculus gracilis; 33 - tractus spinothalamicus lat.; 34 - cells of the posterior horn of the spinal cord; 35 - tractus spinothalamicus lat., its decussation in the white commissure of the spinal cord.

The spinal cord is a section of the central nervous system of the spine, which is a cord 45 cm long and 1 cm wide.

Structure of the spinal cord

The spinal cord is located in the spinal canal. Behind and in front there are two grooves, thanks to which the brain is divided into right and left halves. It is covered with three membranes: vascular, arachnoid and hard. The space between the vascular and arachnoid membranes filled with cerebrospinal fluid.

In the center of the spinal cord you can see gray matter, shaped like a butterfly when cut through. Gray matter consists of motor and interneurons. The outer layer of the brain is white matter of axons collected in descending and ascending pathways.

There are two types of horns in the gray matter: anterior, which contains motor neurons, and posterior, where interneurons are located.

The structure of the spinal cord has 31 segments. From each of them extend the anterior and posterior roots, which, merging, form the spinal nerve. When leaving the brain, the nerves immediately split into roots - posterior and anterior. The dorsal roots are formed with the help of axons of afferent neurons and they are directed into the dorsal horns of the gray matter. At this point they form synapses with efferent neurons, whose axons form the anterior roots of the spinal nerves.

The dorsal roots contain the spinal nodes, which contain sensory nerve cells.

The spinal canal runs through the center of the spinal cord. To the muscles of the head, lungs, heart, thoracic organs and upper extremities, nerves arise from segments of the upper thoracic and cervical parts of the brain. The abdominal organs and trunk muscles are controlled by the segments of the lumbar and chest parts. Muscles of the lower abdominal cavity and muscles lower limbs control the sacral and lower lumbar segments of the brain.

Functions of the spinal cord

There are two main functions of the spinal cord:

• Conductor;
• Reflex.

The conductor function is that nerve impulses move along the ascending pathways of the brain to the brain, and commands are sent through the descending pathways from the brain to the working organs.

The reflex function of the spinal cord is that it allows you to perform the simplest reflexes (knee reflex, withdrawal of the hand, flexion and extension of the upper and lower extremities, etc.).

Only simple motor reflexes are carried out under the control of the spinal cord. All other movements, such as walking, running, etc., require the participation of the brain.

Spinal cord pathologies

Based on the causes of spinal cord pathologies, three groups of spinal cord diseases can be distinguished:

• Developmental defects – postnatal or congenital abnormalities in the structure of the brain;
• Diseases caused by tumors, neuroinfections, spinal circulatory disorders, hereditary diseases of the nervous system;
• Spinal cord injuries, which include bruises and fractures, compression, concussions, dislocations and hemorrhages. They can appear either independently or in combination with other factors.

Any disease of the spinal cord has very serious consequences. A special type of disease includes spinal cord injuries, which, according to statistics, can be divided into three groups:

• Car accidents are the most common cause of spinal cord injury. Driving motorcycles is especially dangerous because there is no backrest to protect the spine.
• A fall from a height can be either accidental or intentional. In any case, the risk of spinal cord damage is quite high. Often athletes, fans of extreme sports and jumping from heights get injured in this way.
• Everyday and extraordinary injuries. They often occur as a result of going down and falling in the wrong place, falling down the stairs or when there is ice. This group also includes knife and bullet wounds and many other cases.

With spinal cord injuries, the conduction function is primarily disrupted, which leads to very disastrous consequences. For example, brain damage in cervical spine leads to the fact that brain functions are preserved, but they lose connections with most organs and muscles of the body, which leads to paralysis of the body. The same disorders occur when peripheral nerves are damaged. If the sensory nerves are damaged, sensation in certain areas of the body is impaired, and damage to the motor nerves impairs the movement of certain muscles.

Most nerves are of a mixed nature, and their damage causes both the inability to move and loss of sensation.

Spinal cord puncture

A spinal puncture involves inserting a special needle into the subarachnoid space. A spinal cord puncture is performed in special laboratories, where the patency of this organ is determined and the pressure of the cerebrospinal fluid is measured. The puncture is carried out both therapeutically and diagnostic purposes. It allows you to timely diagnose the presence of hemorrhage and its intensity, find inflammatory processes in the meninges, determine the nature of the stroke, determine changes in the nature of the cerebrospinal fluid, signaling diseases of the central nervous system.

Often a puncture is performed to administer radiopaque and medicinal fluids.

IN medicinal purposes puncture is carried out to extract blood or purulent fluid, as well as to administer antibiotics and antiseptics.

Indications for spinal cord puncture:

• Meningoencephalitis;
• Unexpected hemorrhages in the subarachnoid space due to rupture of an aneurysm;
• Cysticercosis;
• Myelitis;
• Meningitis;
• Neurosyphilis;
• Traumatic brain injury;
• Liquororrhea;
• Echinococcosis.

Sometimes, during brain surgery, spinal cord puncture is used to reduce intracranial pressure parameters, as well as to facilitate access to malignant neoplasms.

Photograph of an anatomical specimen) are the main element connecting the spinal column into a single whole, and make up 1/3 of its height. The main function of intervertebral discs is mechanical (support and shock-absorbing). They provide flexibility to the spinal column during various movements (bending, rotation). In the lumbar spine, the diameter of the discs is on average 4 cm, and the height is 7–10 mm. The intervertebral disc has a complex structure. In its central part there is a nucleus pulposus, which is surrounded by a cartilaginous (fibrous) ring. Above and below the nucleus pulposus are the end plates.

The nucleus pulposus contains well-hydrated collagen (randomly arranged) and elastic (radially arranged) fibers. At the border between the nucleus pulposus and the fibrous ring (which is clearly defined up to 10 years of life), cells resembling chondrocytes are located with a fairly low density.

Fibrous ring consists of 20–25 rings or plates, between which are located collagen fibers, which are directed parallel to the plates and at an angle of 60° to vertical axis. Elastic fibers are located radially in relation to the rings, which restore the shape of the disc after the movement has taken place. The cells of the annulus fibrosus, located closer to the center, have an oval shape, while at its periphery they elongate and are located parallel to the collagen fibers, resembling fibroblasts. Unlike articular cartilage, disc cells (both the nucleus pulposus and the annulus fibrosus) have long, thin cytoplasmic projections that reach 30 μm or more. The function of these outgrowths remains unknown, but it is assumed that they are capable of sensing mechanical stress in tissues.

End plates They are a thin (less than 1 mm) layer of hyaline cartilage located between the vertebral body and the intervertebral disc. The collagen fibers it contains are arranged horizontally.

Intervertebral disc of a healthy person contains blood vessels and nerves only in the outer plates of the annulus fibrosus. The endplate, like any hyaline cartilage, has no vessels or nerves. Basically, the nerves travel accompanied by vessels, but they can also travel independently of them (branches of the sinuvertebral nerve, anterior and gray communicating branches). The sinuvertebral nerve is the recurrent meningeal branch of the spinal nerve. This nerve leaves the spinal ganglion and enters the intervertebral foramen, where it divides into ascending and descending branches.

As has been shown in animals, the sensory fibers of the sinuvertebral nerve are formed by fibers from both the anterior and posterior roots. It should be noted that the anterior longitudinal ligament is innervated by branches of the spinal ganglion. The posterior longitudinal ligament receives nociceptive innervation from the ascending branches of the sinuvertebral nerve, which also innervates the outer plates of the annulus fibrosus.

With age, there is a gradual blurring of the boundary between the fibrous ring and the nucleus pulposus, which becomes more and more fibrotic. Over time, the disc becomes morphologically less structured - the annular plates of the annulus fibrosus change (merge, bifurcate), collagen and elastic fibers are located more and more chaotically. Cracks often form, especially in the nucleus pulposus. Degeneration processes are also observed in the blood vessels and nerves of the disc. Fragmented cell proliferation occurs (especially in the nucleus pulposus). Cell death occurs over time intervertebral disc. Thus, in an adult, the number of cellular elements decreases by almost 2 times. It should be noted that degenerative changes in the intervertebral disc (cell death, fragmented cell proliferation, fragmentation of the nucleus pulposus, changes in the annulus fibrosus), the severity of which is determined by a person’s age, is quite difficult to differentiate from those changes that would be interpreted as “pathological”.

The mechanical properties (and accordingly the function) of the intervertebral disc are ensured intercellular matrix, the main components of which are collagen and aggrecan (proteoglycan). The collagen network is formed by type I and type II collagen fibers, which constitute approximately 70% and 20% of the dry weight of the entire disc, respectively. Collagen fibers provide strength to the disc and fix it to the vertebral bodies. Aggrecan (the main disc proteoglycan), composed of chondroitin and keratan sulfate, provides hydration to the disc. Thus, the weight of proteoglycans and water in the annulus fibrosus is 5 and 70%, and in the nucleus pulposus – 15 and 80%, respectively. Synthetic and lytic (proteinases) processes constantly occur in the intercellular matrix. However, it is a histologically constant structure, which provides mechanical strength to the intervertebral disc. Despite the morphological similarity with articular cartilage, the intervertebral disc has a number of differences. Thus, in protein glycans (aggrecan) of the disc there is more high content keratan sulfate. In addition, in the same person, disc aggrecans are smaller and have more pronounced degenerative changes than articular cartilage aggrecans.

Let us consider in more detail the structure of the nucleus pulposus and the fibrous ring - the main components of the intervertebral disc.

Nucleus pulposus. According to morphological and biochemical analysis, including microscopic and ultramicroscopic studies, the nucleus pulposus of human intervertebral discs belongs to a type of cartilaginous tissue (V.T. Podorozhnaya, 1988; M.N. Pavlova, G.A. Semenova, 1989; A.M. Zaidman, 1990). The characteristics of the main substance of the nucleus pulposus correspond to the physical constants of a gel containing 83-85% water. Studies by a number of scientists have determined a decrease in the content of the water fraction of the gel with age. Thus, in newborns the nucleus pulposus contains up to 90% water, in a child of 11 years old - 86%, in an adult - 80%, in people over 70 years old - 60% water (W. Wasilev, W. Kuhnel, 1992; R. Putz , 1993). The gel contains proteoglycans, which, along with water and collagen, are the few components of the nucleus pulposus. Glycosaminoglycans in proteoglycan complexes are chondroitin sulfates and, in smaller quantities, keratan sulfate. The function of the chondroitin sulfate-containing region of a proteoglycan macromolecule is to create pressure associated with the spatial structure of the macromolecule. High imbibitional pressure in the intervertebral disc keeps a large number of water molecules. The hydrophilicity of proteoglycan molecules ensures their spatial separation and separation of collagen fibrils. The resistance of the nucleus pulposus to compression is determined by the hydrophilic properties of proteoglycans and is directly proportional to the amount of bound water. Compression forces, acting on the pulpous substance, increase its internal pressure. Water, being incompressible, resists compression. The keratan sulfate region is capable of interacting with collagen fibrils and their glycoprotein sheaths to form cross-links. This enhances the spatial stabilization of proteoglycans and ensures the distribution of negatively charged terminal groups of glycosaminoglycans in the tissue, which is necessary for the transport of metabolites into the nucleus pulposus. The nucleus pulposus, surrounded by a fibrous ring, occupies up to 40% of the area of ​​the intervertebral discs. It is to him that it is distributed most of forces transformed in the nucleus pulposus.

Fibrous ring formed by fibrous plates, which are located concentrically around the nucleus pulposus and are separated thin layer matrix or layers of loose connective tissue. The number of plates varies from 10 to 24 (W.C. Horton, 1958). In the anterior part of the fibrous ring the number of plates reaches 22-24, and in the posterior part it decreases to 8-10 (A.A. Burukhin, 1983; K.L. Markolf, 1974). The plates of the anterior sections of the fibrous ring are located almost vertically, and the rear ones have the form of an arc, the convexity of which is directed posteriorly. The thickness of the anterior plates reaches 600 microns, the rear ones - 40 microns (N.N. Sak, 1991). The plates consist of bundles of densely packed collagen fibers of varying thickness from 70 nm or more (T.I. Pogozheva, 1985). Their arrangement is ordered and strictly oriented. The bundles of collagen fibers in the plates are biaxially oriented relative to the longitudinal axis of the spine at an angle of 120° (A. Peacock, 1952). The collagen fibers of the outer plates of the annulus fibrosus are woven into the deep fibers of the lateral longitudinal ligament of the spine. The fibers of the outer plates of the fibrous ring are attached to the bodies of adjacent vertebrae in the area of ​​the marginal border - the limbus, and are also embedded in bone tissue in the form of Sharpey's fibers and tightly fuses with the bone. The fibrils of the internal plates of the annulus fibrosus are woven into the fibers of hyaline cartilage, separating the tissue of the intervertebral disc from the spongy bone of the vertebral bodies. This is how a “closed package” is formed, which closes the nucleus pulposus into a continuous fibrous frame between the fibrous ring along the periphery and the hyaline plates connected above and below by a single system of fibers. In the plates of the outer layers of the annulus fibrosus, alternating differently oriented fibers with different densities were identified: loosely packed ones alternate with densely packed ones. In dense layers, the fibers split and move into loosely packed layers, thus creating one system fibers The loose layers are filled with tissue fluid and, being an elastic shock-absorbing tissue between dense layers, provide elasticity to the fibrous ring. The loose fibrous part of the annulus fibrosus is represented by thin, unoriented collagen and elastic fibers and a ground substance consisting mainly of chondroitin-4-6-sulfate and hyaluronic acid.

The height of the discs and spine is not constant throughout the day. After a night's rest, their height increases, and by the end of the day it decreases. The daily fluctuation in the length of the spine reaches 2 cm. The deformation of the intervertebral discs varies with compression and tension. If, when compressed, the disks flatten by 1-2 mm, then when stretched, their height increases by 3-5 mm.

Normally, there is a physiological protrusion of the disc, which is that the outer edge of the fibrous ring, under the action of an axial load, protrudes beyond the line connecting the edges of adjacent vertebrae. This protrusion of the posterior edge of the disc towards the spinal canal is clearly visible on myelograms and alignment. usually, does not exceed 3 mm . Physiological protrusion of the disc increases with extension of the spine, disappears or decreases with flexion.

Pathological protrusion of the intervertebral disc differs from physiological the fact that widespread or local protrusion of the fibrous ring leads to a narrowing of the spinal canal and does not decrease with movements of the spine. Let's move on to consider the pathology of the intervertebral disc.

PATHOLOGY ( addition)

The main element of intervertebral disc degeneration is decrease in the number of protein glycans. Fragmentation of aggrecans occurs, loss of glycosaminoglycans, which leads to a drop in osmotic pressure and, as a result, disc dehydration. However, even in degenerated discs, cells retain the ability to produce normal aggrecans.

Compared to protein glycans, the collagen composition of the disc changes to a lesser extent. Thus, the absolute amount of collagen in the disc, as a rule, does not change. However, redistribution is possible various types collagen fibers. In addition, the process of collagen denaturation occurs. However, by analogy with protein glycans, disc cell elements retain the ability to synthesize healthy collagen even in a degenerated intervertebral disc.

Loss of protein glycans and dehydration of the disc lead to a decrease in their shock-absorbing and supporting functions. The intervertebral discs decrease in height and gradually begin to prolapse into the spinal canal. Thus, improper redistribution of axial load on the endplates and annulus fibrosus can provoke discogenic pain. Degenerative-dystrophic changes are not limited only to the intervertebral disc, since changes in its height lead to pathological processes in neighboring formations. Thus, a decrease in the supporting function of the disc leads to overload in the facet joints, which contributes to the development of osteoarthritis and a decrease in the tension of the yellow ligaments, which leads to a decrease in their elasticity and corrugation. Disc prolapse, arthrosis of the facet joints and thickening (corrugation) of the yellow ligaments lead to spinal stenosis.

It has now been proven that compression of the root by an intervertebral hernia is not the only cause of radicular pain, since about 70% of people do not experience pain when the roots are compressed by a hernial protrusion. It is believed that in some cases, when a herniated disc comes into contact with a root, sensitization of the latter occurs due to aseptic (autoimmune) inflammation, the source of which is the cells of the affected disc.

One of the main causes of intervertebral disc degeneration is violation of adequate nutrition of its cellular elements. In vitro, it was shown that intervertebral disc cells are quite sensitive to oxygen deficiency, glucose and pH changes. Impaired cell function leads to changes in the composition of the intercellular matrix, which triggers and/or accelerates degenerative processes in the disc. Nutrition of the cells of the intervertebral disc occurs indirectly, since the blood vessels are located from them at a distance of up to 8 mm (capillaries of the vertebral bodies and outer plates of the fibrous ring.

Disk power failure can be due to many reasons: various anemias, atherosclerosis. Besides, metabolic disorders observed with overload and insufficient load on the intervertebral disc. It is believed that in these cases there is a restructuring of the capillaries of the vertebral bodies and/or compaction of the endplates, which impedes diffusion nutrients. However, it should be noted that the degenerative process is associated only with incorrect execution of movements during physical activity, while their correct implementation increases the intradiscal content of protein glycans.

There are several stages of degenerative-dystrophic changes in the intervertebral disc:
stage 0 - the disk is not modified
stage 1 - small tears of the inner 1/3 of the annular plates of the annulus fibrosus
stage 2 - significant destruction of the disc occurs, but the outer rings of the annulus fibrosus are preserved, which prevent herniation; there is no compression of the roots; at this stage, in addition to back pain, it may radiate to the legs to the level of the knee joint
stage 3 - cracks and tears are observed along the entire radius of the fibrous ring; the disc prolapses, causing tears of the posterior longitudinal ligament

Currently, this classification has been slightly modified, since it did not include compression syndromes.

Attempts to create a real classification based on data computed tomography, undertaken from 1990 and completed in 1996 (Schellhas):
stage 0 - inserted into the center of the disk contrast agent does not leave the boundaries of the nucleus pulposus
stage 1 - at this stage the contrast penetrates to the inner 1/3 of the annulus fibrosus
stage 2 - contrast extends to 2/3 of the annulus fibrosus
stage 3 - crack along the entire radius of the fibrous ring; the contrast penetrates to the outer plates of the fibrous ring; it is believed that pain occurs at this stage, since only the outer layers of the disc are innervated
stage 4 - there is a spread of contrast around the circumference (reminiscent of an anchor), but no more than 30°; this is due to the fact that radial discontinuities merge with concentric ones
stage 5 - contrast penetration into the epidural space occurs; Apparently, this provokes aseptic (autoimmune) inflammation in nearby soft tissues, which sometimes causes radiculopathy even without obvious signs compression

Data comparative anatomy allow us to consider the intervertebral disc as articular cartilage, both components of which - the nucleus pulposus (pulpous) and the fibrous ring - are currently classified as fibrous cartilage, and the endplates of the vertebral bodies are likened to articular surfaces. The results of pathomorphological and histochemical studies made it possible to classify degenerative changes in the intervertebral disc as a multifactorial process. Disc degeneration is based on a genetic defect. Several genes responsible for the strength and quality of osteochondral structures have been identified: genes for the synthesis of type 9 collagen, aggrecan, vitamin D receptor, metalloproteinase. Genetic “breakage” is systemic in nature, which is confirmed by the high prevalence of intervertebral disc degeneration in patients with osteoarthritis. The trigger point for the development of degenerative changes in the disc is structural damage to the fibrous ring due to inadequate physical activity. The ineffectiveness of reparative processes in the intervertebral disc leads to an increase in degenerative changes and the appearance of pain. Normally, the posterior outer layers of the annulus fibrosus (1–3 mm) and the adjacent posterior longitudinal ligament are equipped with nociceptors. It has been proven that in a structurally changed disc, nociceptors penetrate the anterior part of the annulus fibrosus and nucleus pulposus, increasing the density of the nociceptive field. In vivo, nociceptor stimulation is supported not only by mechanical stress, but also by inflammation. A degeneratively altered disc produces pro-inflammatory cytokines IL-1, IL-6, IL-8, as well as TNF (tumor necrosis factor). Researchers emphasize that the contact of elements of the nucleus pulposus with nociceptors on the periphery of the annulus fibrosus helps to lower the threshold of excitability of nerve endings and increase their perception of pain. It is believed that the intervertebral disc is most associated with pain - at the stage of disc prolapse, with a decrease in its height, with the appearance of radial cracks in the fibrous ring. when degeneration of the intervertebral disc leads to herniation, additional reason pain becomes a root or nerve. Inflammatory agents produced by hernia cells increase the sensitivity of the root to mechanical pressure. Changes in pain threshold play an important role in the development of chronic pain.

Attempts have been made to identify the mechanisms of discogenic pain using discography. It has been shown that pain occurs with the introduction of substances like glycosaminoglycans and lactic acid, with compression of the roots, with hyperflexion of the facet joints. It has been suggested that the endplates may be the source of pain. Ohnmeiss in 1997 showed that complete rupture of the annulus fibrosus or disc herniation is not necessary for the occurrence of leg pain. He proved that even at stage 2 (when the outer plates of the annulus fibrosus remain intact), pain in the lower back occurs, radiating to the leg. It has now been proven that pain from one level can also come from underlying segments, for example, pathology of the L4–L5 disc can cause pain in the L2 dermatome.

For formation pain syndrome in case of intervertebral disc herniation influence:
violation of the biomechanics of the motor act
violation of posture and balance of the muscular-ligamentous-fascial apparatus
imbalance between the anterior and posterior muscle girdle
imbalances in the sacroiliac joints and other pelvic structures

It should be noted that the severity clinical manifestations intervertebral disc herniation is also caused by the ratio of the size of the intervertebral hernia to the size of the spinal canal where the spinal cord and its roots are located. A favorable ratio is a small hernia (from 4 to 7 mm) and a wide spinal canal (up to 20 mm). And the lower this indicator, the less favorable the course of the disease, requiring a longer course of treatment.

In the case of an association of clinical manifestations of vertebral pathology with degenerative changes in the intervertebral disc, the term used in foreign literature is - "degenerative disc disease"- DBD (degenerative disk disease - DDD). DBD is a component of a single process – osteoarthritis of the spine.

Stages of formation of herniated intervertebral discs according to Decolux A.P. (1984):
protruding disk- bulging of the intervertebral disc, which has lost its elastic properties, into the spinal canal
failed disc- disc masses are located in the intervertebral space and compress the contents of the spinal canal through the intact posterior longitudinal ligament
prolapsed disc - most often detected in acute or traumatic hernia; partial prolapse of intervertebral disc masses into the spinal canal accompanying rupture of the posterior longitudinal ligament; direct compression of the spinal cord and roots
free sequestered disc- a disc lying freely in the cavity of the spinal canal (in acute cases or as a result of injury may be accompanied by rupture meninges and intradural location of hernial masses

Most often in the lumbosacral spine, hernias occur in the intervertebral discs at the L5-S1 level (48% of total number hernias at the lumbosacral level) and at the L4-L5 level (46%). Less commonly, they are localized at the level of L3-L4 (5%) and most rarely at the level of L2-L3 (less than 1%).

Anatomical classification of disc herniations:
simple disc herniation , in which the posterior longitudinal ligament is torn, and a larger or smaller portion of the disc, as well as the nucleus pulposus, protrudes into the spinal canal; can be in two forms:
- free disc herniation due to “breaking”: the contents of the disc pass through the posterior longitudinal ligament, but still remain partially attached to areas of the intervertebral disc that have not yet prolapsed or to the corresponding vertebral plane;
- wandering hernia– has no connection with the intervertebral space and moves freely in the spinal canal;
intermittent disc herniation - occurs from an unusually strong mechanical load or from strong compression exerted on the spine, with its subsequent return to its original position after the load is removed, although the nucleus pulposus may remain permanently dislocated.

Topographic classification of disc herniation:
intraspinal disc herniation – completely located in the spinal canal and emanating from the middle part of the disc, this hernia can be in three positions:
- in the dorsal medial(Stukey group I) causes compression of the spinal cord or cauda equina;
- paramdial (group II according to Stukey) causes unilateral or bilateral compression of the spinal cord;
- dosolateral(Stukey group III) compresses the spinal cord or intraspinal nerve roots, or the lateral part of the vertebral plate on one or both sides; this is the most common form, since at this level there is a weak zone in the disc - the posterior longitudinal ligament is reduced to several fibers located on the lateral parts;
disc herniation located inside the intervertebral foramen , comes from the outer part of the disc and compresses the corresponding root towards the articular process;
lateral disc herniation comes from the most lateral part of the disc and can cause various symptoms, provided that it is located in the lower part of the cervical segment, while squeezing vertebral artery and spinal nerve;
ventral disc herniation , emanating from the ventral edge, does not give any symptoms and is therefore of no interest.

According to the direction of prolapse of the sequestrum, hernias are divided into (Handbook of Vertebroneurology, Kuznetsov V.F. 2000):
anterolateral, which are located outside the anterior semicircle of the vertebral bodies, peel off or perforate the anterior longitudinal ligament, can cause sympathalgic syndrome when the paravertebral sympathetic chain is involved in the process;
posterolateral, which pierce the posterior half of the fibrous ring:
- median hernias – by midline;
- paramedian – close to the midline;
- lateral hernias(foraminal) - on the side of the midline (from the posterior longitudinal ligament).

Sometimes two or more types of disc herniations are combined. ABOUT vertebral body hernia (Schmorl's hernia) cm. .

Intervertebral disc degeneration is visualized by magnetic resonance imaging (MRI). The stages of disc degeneration are described (D. Schlenska et al.):
M0 – norm; nucleus pulposus spherical or ovoid in shape
M1 – loal (segmental) decrease in the degree of luminescence
M2 – disc degeneration; disappearance of the glow of the nucleus pulposus

Types (stages) of vertebral body lesions associated with intervertebral disc degeneration, according to MRI data:
Type 1 – a decrease in signal intensity on T1-weighted images and an increase in signal intensity on T2-weighted images indicate inflammatory processes in the bone marrow of the vertebrae
Type 2 - an increase in signal intensity on T1 and T2 - weighted images indicates the replacement of normal bone marrow adipose tissue
Type 3 - a decrease in signal intensity on T1 and T2 - weighted images indicates processes of osteosclerosis

Main diagnostic criteria intervertebral disc herniation is:
the presence of vertebrogenic syndrome, manifested by pain, limited mobility and deformities (antalgic scoliosis) in the affected part of the spine; tonic tension of the paravertebral muscles
sensory disorders in the area of ​​the neurometamere of the affected root
movement disorders in the muscles innervated by the affected root
decreased or lost reflexes
the presence of relatively deep biomechanical disturbances in motor compensation
data from computed tomography (CT), magnetic resonance imaging (MRI) or radiographic examination, verifying the pathology of the intervertebral disc, spinal canal and intervertebral foramina
data from electroneurophysiological studies (F-wave, H-reflex, somatosensory evoked potentials, transcranial magnetic stimulation), recording conduction disturbances along the root, as well as the results of needle electromyography with analysis of action potentials of motor units, allowing to establish the presence of denervation changes in the muscles of the affected myotome

Clinical significance sizes of protrusions and herniations of the intervertebral disc:
cervical section of the spinal column:
1-2 mm- Not big size protrusion
3-4 mm- average protrusion size(urgent outpatient treatment required)
5-6 mm- (outpatient treatment is still possible)
6-7 mm and more- large size of intervertebral hernia(requires surgical treatment)
lumbar and thoracic sections of the spinal column:
1-5 mm- small protrusion size(outpatient treatment is required, treatment at home is possible: spinal traction and special gymnastics)
6-8 mm- average size of intervertebral hernia(outpatient treatment required, surgical treatment not indicated)
9-12 mm- large size of intervertebral hernia(urgent outpatient treatment is required, surgical treatment only for symptoms of compression of the spinal cord and elements of the cauda equina)
more than 12 mm- large prolapse or sequestered hernia(outpatient treatment is possible, but on the condition that if symptoms of compression of the spinal cord and elements of the cauda equina appear, the patient has the opportunity to undergo surgery the next day; with symptoms of spinal cord compression and a number of MRI signs, immediate surgical treatment is required)

Note: when the spinal canal narrows, the smaller intervertebral hernia behaves like a larger one.

There is such a rule, What disc bulge is considered severe and clinically significant if it exceeds 25% anteroposterior diameter of the spinal canal (according to other authors - if it exceeds 15% anteroposterior diameter of the spinal canal) or narrows the canal to critical level 10 mm.

Periodization of compression manifestations of spinal osteochondrosis against the background of intervertebral disc herniation:
acute period (stage of exudative inflammation) - duration 5-7 days; the hernial protrusion swells - the swelling reaches a maximum on days 3-5, increases in size, compressing the contents of the epidural space, including the roots, the vessels that feed them, as well as the vertebral venous plexus; sometimes there is a breakup hernial sac and its contents pour into the epidural space, leading to the development of reactive epiduritis or down along the posterior longitudinal ligament; pain gradually increases; any movement causes unbearable suffering; The first night is especially difficult for patients; main question which needs to be decided in this situation - whether or not the patient needs urgent surgical intervention; absolute indications for surgery are: myeloschaemia or spinal stroke; reactive epiduritis; compression of two or more roots along the length; pelvic disorders
subacute period(2-3 weeks) - the exudative phase of inflammation is replaced by a productive one; adhesions gradually form around the hernia, which deform the epidural space, compress the roots, and sometimes fix them to the surrounding ligaments and membranes
early recovery period - 4-6 weeks
late recovery period(6 weeks - six months) - the most unpredictable period; the patient feels healthy, but the disc has not yet healed; to avoid unpleasant consequences, during any physical activity it is recommended to wear a fixation belt

To characterize the degree of disc protrusion, contradictory terms are used: “disc herniation”, “ disc protrusion", "disc prolapse". Some authors use them almost as synonyms. Others suggest using the term “disc protrusion” to refer to the initial stage of disc protrusion, when the nucleus pulposus has not yet broken through the outer layers of the annulus fibrosus, the term “disc herniation” only when the nucleus pulposus or its fragments have broken through the outer layers of the annulus fibrosus, and the term “disc prolapse” only refers to the prolapse of hernial material that has lost its connection with the disc into the spinal canal. Still others propose to distinguish between intrusions, in which the outer layers of the annulus fibrosus remain intact, and extrusions, in which the hernial material breaks through the outer layers of the annulus fibrosus and the posterior longitudinal ligament into the spinal canna.

Russian authors(Magomedov M.K., Golovatenko-Abramov K.V., 2003), based on the use of Latin roots in term formation, suggest the use of the following terms:
“protrusion” (prolapse) – protrusion of the intervertebral disc beyond the vertebral bodies due to stretching of the fibrous ring without significant ruptures. At the same time, the authors point out that protrusion and prolapse are identical concepts and can be used as synonyms;
“extrusion” - protrusion of the disc caused by rupture of the FC and the release of part of the nucleus pulposus through the resulting defect, but maintaining the integrity of the posterior longitudinal ligament;
“true hernia”, in which not only the fibrous ring, but also the posterior longitudinal ligament ruptures.

Japanese authors(Matsui Y., Maeda M., Nakagami W. et al., 1998; Takashi I., Takafumi N., Tarou K. et al., 1996) distinguish four types of hernial protrusions, using the following terms to designate them:
“protrusion" (P-type, P-type) - protrusion of the disc in which there is no rupture of the fibrous ring or (if present) does not extend to its outer parts;
« subligamentous extrusion"(SE-type, SE-type) - a hernia in which perforation of the fibrous ring occurs while preserving the posterior longitudinal ligament;
« transligamentous extrusion"(TE-type, TE-type) - a hernia that ruptures not only the fibrous ring, but also the posterior longitudinal ligament;
“sequestration” (C-type, S-type) – a hernia in which part of the nucleus pulposus ruptures the posterior longitudinal ligament and is sequestered in the epidural space.

Swedish authors(Jonsson B., Stromqvist B., 1996; Jonsson B., Jonsson R., Stromqvist B., 1998) there are two main types of hernial protrusions - so-called contained hernias and noncontained hernias. The first group includes: “protrusion” - a protrusion in which ruptures of the fibrous ring are absent or minimally expressed; and “prolapse” - dislocation of the material of the nucleus pulposus to the posterior longitudinal ligament with complete or almost complete break fibrous ring. The second group of hernial protrusions is represented by extrusion and sequestration. During extrusion, the posterior longitudinal ligament is ruptured, but the fallen fragment of the nucleus pulposus remains connected to the rest of it, in contrast to sequestration, in which this fragment separates and becomes free.

One of the most clear schemes was proposed by J. McCulloch and E. Transfeldt (1997), who distinguish:
1) disc protrusion- How initial stage disc herniation, in which all disc structures, including the annulus fibrosus, are displaced beyond the line connecting the edges of two adjacent vertebrae, but the outer layers of the annulus fibrosus remain intact; material from the nucleus pulposus can penetrate into the inner layers of the annulus fibrosus (intrusion);
2) subannular (subligamentary) extrusion , in which the damaged nucleus plosus or its fragments are squeezed out through a crack in the annulus fibrosus, but do not break through the outermost fibers of the annulus fibrosus and the posterior longitudinal ligament, although they can move up or down in relation to the disc;
3) transannular (transligamentary) extrusion , in which the nucleus pulposus or its fragments break through the outer fibers of the annulus fibrosus and/or the posterior longitudinal ligament, but maintain connection with the disc;
4) prolapse (loss) , characterized by sequestration of the hernia with loss of connection with the remaining disc material and prolapse into the spinal canal.

A review of the terminology of disc herniations would not be complete without noting that, according to a number of authors, the term “ disc herniation» can be used when the displacement of the disc material occupies less than 50% of its circumference. In this case, the hernia can be local (focal), if it occupies up to 25% of the disc circumference, or diffuse, occupying 25-50%. A protrusion of more than 50% of the disc circumference is not a hernia, but is called “ disc bulging"(bulging disk).

To overcome terminological confusion, they propose (a team of authors from the Department of Neurology of the Russian medical academy postgraduate education: dr med. Sciences, Professor V.N. Stock; Dr. med. Sci. Professor O.S. Levin; Ph.D. honey. Sci. Associate Professor B.A. Borisov, Yu.V. Pavlov; Ph.D. honey. Sciences I. G. Smolentseva; Dr. med. Sciences, Professor N.V. Fedorov) when formulating a diagnosis, use only one term - “ disc herniation» . In this case, a “disc herniation” can be understood as any protrusion of the edge of the disc beyond the line connecting the edges of adjacent vertebrae, which exceeds physiological limits (normally no more than 2-3 mm).

To clarify the degree of disc herniation, the same team of authors (employees of the Department of Neurology of the Russian Medical Academy of Postgraduate Education: Doctor of Medical Sciences, Professor V.N. Shtok; Doctor of Medical Sciences, Professor O.S. Levin; Candidate of Medical Sciences Scientific Associate Professor B.A. Borisov, Yu.V. Pavlov; Candidate of Medical Sciences I.G. Smolentseva; Doctor of Medical Sciences, Professor N.V. Fedorova) propose the following scheme:
I degree– slight protrusion of the fibrous ring without displacement of the posterior longitudinal ligament;
II degree– medium-sized protrusion of the fibrous ring. occupying no more than two-thirds of the anterior epidural space;
III degree– a large disc herniation that displaces the spinal cord and dural sac posteriorly;
IV degree– massive disc herniation. compressing the spinal cord or dural sac.

!!! It should be emphasized that the presence of tension symptoms, radicular symptoms, and local pain does not necessarily indicate that a disc herniation is the cause of the pain syndrome. Diagnosis of disc herniation as a cause of neurological syndrome is possible only when clinical picture corresponds to the level and degree of disc protrusion.

Causes of spinal canal stenosis. Classification of spinal canal stenosis. Symptoms of lumbar spinal canal stenosis The spinal canal is the place where the spinal cord passes. It is formed from the anterior surface of the vertebral bodies, the posterior yellow ligament and the inner surface of the arches, with the lateral legs of the vertebral arch.

Normally, its diameter in the cranial region is about 20 mm, in the cervical, thoracic, and lumbar regions it decreases slightly and is about 17 mm. The diameter of the spinal cord is 10-15 mm. Its diameter increases in ascending order, and by the age of twenty it has the above dimensions. But, unfortunately, some people develop degenerative processes in the walls of the spinal canal as they grow older. This leads to a narrowing of the spinal cord canal.

An analogy can be drawn with a pipe. The walls of the pipe will accumulate rust as it is used, and the internal diameter will decrease. In the case of spinal canal stenosis, the essence is the same, only here the degenerative process predominates, that is, the tissues that surround the canal thicken, marginal osteophytes grow from the vertebral bodies, the spine may have pathological curvatures, because of this, the internal diameter decreases.

Spinal stenosis can be congenital. We are talking about an anomaly here intrauterine development. Stenosis can occur in both the cervical and lumbar regions. The causes of congenital narrowing of the spinal canal are described below.

You should know the anatomy of the spinal column and canal to understand how narrowing of the spinal canal develops.

Anatomy of the spine

Normally, the spine has 2 types of curves: lordosis and kyphosis. Lordosis is a forward bend of the spine, it can be cervical and lumbar, kyphosis is a backward bend, it can be thoracic and sacral. By appearance the spinal column resembles the letter S. These physiological curves are needed to maintain balance and to ensure that the body receives less shock during sudden movements and turns.

The spinal cord follows these curves. It starts from the first cervical spine and lasts to the first or second lumbar vertebrae, then a rudimentary part called the cauda equina continues, it is attached to the walls of the sacral canal. There is fatty tissue between the walls of the spinal canal and the brain itself. Thanks to it, when a narrowing of the channel develops, the process can be compensated.

Causes

The reasons may be the following changes:

• intervertebral disc herniation;
• tumors;
• inflammation of the intervertebral joints;
• marginal osteophytes on the vertebral body;
• thickening of the ligamentum flavum;
• pathological curvature of the spinal column;
• vertebral displacement, etc.

These changes lead to local ischemia. Ischemia is oxygen starvation, that is, oxygen delivery to the spinal cord decreases. Because of this, aseptic inflammation may develop, which leads to a local increase in pressure.

During walking or running, in order to ensure normal muscle function, the spinal cord requires more oxygen, and when the spinal canal is narrowed, this turns out to be impossible, since the vessels in this place are narrowed and experience great pressure. This is manifested by pain, which intensifies when walking and decreases with rest.

The cause of congenital stenosis of the spinal canal is the anatomical features of the spinal bones. For example: shortening and thickening of their arch, decreasing the height of their body.

Classification of the disease

The disease is divided:

1. According to the anatomical structure:
   • central;
   • lateral.
2. By etiology:
   • congenital;
   • acquired;
   • mixed.
3. By degree of narrowing:
   • absolute;
   • relative.

The acquired disease most often develops in people over 50 years of age.

Central stenosis is a narrowing of the space between the vertebral bodies and their arches. Lateral stenosis is a narrowing of the intervertebral foramen where the radicular nerves are located. A narrowing of the canal up to 12 mm is considered relative stenosis, and up to 10 mm is considered absolute stenosis.

Spinal stenosis often occurs with the last degree of osteochondrosis (lumbar spine). Against the background of instability of the spinal motion segment, compensatory mechanisms develop, such as the growth of osteophytes and arthrosis of the intervertebral joint. They cause narrowing of both the spinal canal and the intervertebral foramina where the roots are located. Thus, degenerative stenosis of this canal occurs.

Symptoms

Most of all, patients complain of pain in the lower back, buttocks, thighs and calf muscles. Pain usually appears during physical activity and disappears with rest, which is associated with the physiological straightening of lordosis during vertical position bodies.

When lordosis straightens, the intervertebral space becomes narrower than when horizontal position body, and spinal canal stenosis is aggravated by a physiological decrease in the space between the vertebrae. This clinically resembles intermittent claudication of vascular origin.

Also, when the roots are compressed, the sensitivity of the skin decreases. There is a feeling of weakness in the legs, and patients are forced to spare their legs when walking. Flabbiness of the calf muscles is noted.

Diagnostic methods

The main symptom that patients complain about is pain. Therefore, at the appointment, the doctor will ask about their nature: when they increase, how they decrease and where they spread. Spinal stenosis is known to cause radicular symptoms, so your doctor will ask about decreased sensation and weakness in the leg.

In order to determine some symptoms, the doctor will do several test exercises. For example: in a supine position, he will ask you to straighten one leg, then the other. Tendon reflexes will be tested.

Used to make a diagnosis instrumental methods studies: X-ray, MRI (magnetic resonance imaging), CT (computed tomography).

Treatment

Stenosis is treated using the following methods: conservative, surgical and additional. Conservative therapy is, first of all, taking painkillers and anti-inflammatory drugs. Blockade of the stenotic area with steroid hormones and painkillers is considered more effective. They have a good effect, as they reduce swelling and improve blood circulation.

The following additional treatment methods are also used: massage, electrotherapy, acupuncture and gymnastic exercises. Exercise helps strengthen the muscles of the back, abdomen and legs, which helps increase resistance to disease. Getting into the habit of doing exercises is a good guarantee that the symptoms of the disease will be forgotten.

The following types of exercises are suggested: first, lie on your back, relax, put your arms along your body, alternately or together pull your legs bent in knee joint, to the chest; second - also, lying on your back, raise your legs one by one, straightened at the knee joint; third - lying on your back, bend your legs at the knee joint, spread your arms to the sides and move your legs to the sides, without turning your body. Exercises should be done slowly, without sudden movements, and do not forget to inhale and exhale for each movement.

When the roots are compressed by a disc herniation in the lumbosacral region with severe pain, surgical treatment is indicated. Also, if symptoms of compression of the cauda equina are detected, immediate surgery is indicated, since the changes may well be irreversible. Surgeries are indicated when conservative therapy is ineffective, with increased pain. Spinal stenosis is treated with the following types of operations: removal of disc herniation, structures that compress nerve root(spinal cord), stabilization of the spinal motion segment.

Postoperative period

The rehabilitation period is carried out by a rehabilitation doctor who will help you correctly and safely return to a normal lifestyle. He picks up individual course treatment and a set of exercises to strengthen the spinal column. Compliance with treatment measures will improve the chances of effective treatment.