Vacuum effect (phenomenon) of a disc burr. Vacuum phenomenon in the spinal canal - the cause of neurological symptoms requiring surgical treatment Vacuum phenomenon of the spine what to do

The vacuum phenomenon of the spine is synonymous with disc degeneration with the formation of gas bubbles inside the disc. The gas in the thickness of the disk is of mixed composition with a predominance of nitrogen. External protrusion of the disc is usually not observed.

phenomenon vacuum phenomenon

All body tissues contain gases, their solubility in media depends on pressure. This can be well imagined by decompression sickness or when a person is flying on an airplane. The pressure changes with the composition of the blood and gas.

There is a certain amount of gel (fluid) between the articular surfaces of the spine and the ligamentous apparatus.

When this space is forcibly stretched, the volume of the fluid tends to increase and the pressure drops, as a result of which the solubility of nitrogen decreases, and the gas is released into the joint cavity.

At a young age, the disc normally acts as a tight shock-absorbing cushion, consisting of a strong fibrous ring inside which there is a pulpous nucleus. With age or with diseases of the spine, the ring weakens and gas accumulates.

Diagnostics

The vacuum effect is detected mainly when examining the spine for MRI, CT. The accumulation of gas in the intervertebral discs is the cause of neuralgic symptoms and requires surgical intervention. The vacuum effect is an indicator of the unstable state of the spine.

The FRI radiology method allows the radiologist to track the instability of the spinal column, the course of the pathological process. The solution of a number of problems depends on the correct diagnosis, including the choice medical method, employment, forecast, sports and professional orientation.

The vacuum phenomenon of the spine is synonymous with disc degeneration with the formation of gas bubbles inside the disc. The gas in the thickness of the disk is of mixed composition with a predominance of nitrogen. External protrusion of the disc is usually not observed.

phenomenon vacuum phenomenon

All body tissues contain gases, their solubility in media depends on pressure. This can be well imagined by decompression sickness or when a person is flying on an airplane. The pressure changes with the composition of the blood and gas.

There is a certain amount of gel (fluid) between the articular surfaces of the spine and the ligamentous apparatus.

When this space is forcibly stretched, the volume of the fluid tends to increase and the pressure drops, as a result of which the solubility of nitrogen decreases, and the gas is released into the joint cavity.

At a young age, the disc normally acts as a tight shock-absorbing cushion, consisting of a strong fibrous ring inside which there is a pulpous nucleus. With age or with diseases of the spine, the ring weakens and gas accumulates.

Diagnostics

The vacuum effect is detected mainly when examining the spine for MRI, CT. The accumulation of gas in the intervertebral discs is the cause of neuralgic symptoms and requires surgical intervention. The vacuum effect is an indicator of the unstable state of the spine.

The FRI radiology method allows the radiologist to track the instability of the spinal column, the course of the pathological process. The solution of a number of problems depends on the correct diagnosis, including the choice of a treatment method, employment, prognosis, sports and professional orientation.

Osteochondrosis on x-ray (r-gram) is clearly expressed at the 2-4th degree of the disease. Signs of pathology are characterized by a decrease in the height of the intervertebral discs, displacement of individual vertebrae, as well as a weakening or strengthening of the physiological curves of the spinal column.

If disks C5-C7 are affected in cervical region of the spine, there is a straightening and curvature of kyphosis in the neck.

In the lumbar region, osteochondrosis manifests itself more often than in other areas. The condition occurs due to the anatomical features of the structure of the spinal column. Its lower sections account for the maximum load when lifting weights, performing physical exercises.

If degenerative-dystrophic processes are not treated in a timely manner, the disease progresses rapidly. Over time, the distance between the vertebrae decreases. Nerve root entrapment may occur. Because of this, pathological symptoms of the disease arise: radicular, vertebral and myofascial.

X-ray images (r-grams) do not show pinching of the nerves and hypertonicity of the muscles. The degree of severity of degenerative-dystrophic diseases of the spine on r-grams is determined by the degree of narrowing of the intervertebral discs, displacement of the vertebrae back and forth, instability of the vertebral segments.

How can spinal instability be seen on x-rays?

Spinal instability on r-images is determined by the following symptoms:

• hypermobility;
• instability;
• hypomobility.

Hypermobility is characterized by excessive displacement of a vertebra in the affected segment of the spinal column. In addition to displacement in pathology, the height of the intervertebral fissure may decrease. In the initial stages of the disease, it is reduced by about one-fourth.

It is better to assess this condition on radiographs with maximum extension and flexion of the spinal axis (functional tests). At the same time, the state of adjacent vertebrae and the posterior sections of the spinal canal is disturbed.

Hypomobility is characterized by a decrease in the distance between adjacent segments with minimal (than normal) movement of the vertebrae during exercise. functional tests(maximum flexion and extension). Osteochondrosis on the r-image is manifested by a change in the height of the intervertebral discs.

Extension or flexion is accompanied by adynamia of the motor segment of the spinal column against the background of degenerative-dystrophic changes in the spine.

In case of instability radiological signs characterized by the following symptoms:

1. displacement of the vertebrae back and forth and to the sides;
2. angular deformation of the affected segment;
3. within two vertebrae, a deviation in the vertical axis of more than 2 mm is a variant of the pathology;
4. in children, increased mobility can be observed in the C2 segment, therefore, when a difference in the segment of 2 mm is obtained on r-images in children, one cannot speak of pathological symptoms.

The manifestation of instability may be a sign of degenerative-dystrophic changes in the spinal column, but this is not always the case. For example, radiological signs of hyper- and hypomobility can be after traumatic injuries of the spine.

What can be seen on an X-ray with a disease

Loss of intervertebral disc turgor is characterized by a decrease in their elasticity. This phenomenon is observed in early stages pathology. If there is no lateral curvature of the spinal column (scoliosis), the symptoms of pathology may not be seen on the x-ray.

In the initial stages of the disease, a qualified radiologist notes not a narrowing of the intervertebral fissure, but its expansion.

Sometimes, against the background of degenerative-dystrophic changes in the intervertebral segment, a vacuum phenomenon can be traced in the cartilaginous disc. In this area, there is an accumulation of air or the deposition of calcium salts.

X-ray signs of osteochondrosis on an x-ray:

• narrowing of the intervertebral fissure;
• destruction of the endplates of the vertebrae with subchondral osteosclerosis;
• disc penetration into the vertebral body (Pommer's nodes);
• marginal growths along the corners of the vertebral bodies;
• compensatory reactions at increased load.

To detect degenerative-dystrophic changes on the r-gram, it is necessary to carefully analyze the radiological signs. It will be possible to establish a diagnosis only after comparing the X-ray manifestations of the disease with each other and assessing the pathogenetic manifestations.

On the X-ray, you can detect the 2nd-4th degree of the disease. To identify the initial stage of pathology, the doctor must be highly qualified.

The intervertebral disc is a cartilaginous connection between the vertebral bodies, they perform a shock-absorbing function, having in their composition a slightly compressible nucleus pulposus and a fibrous ring that does not allow it to go beyond the disc. When the annulus fibrosus ruptures, part of the nucleus pulposus comes out under pressure and forms a protrusion in the region of the spine - this is the so-called disc herniation.

But there are conditions in which the fibrous ring does not break, but only becomes thinner and protrudes beyond the posterior contour of the vertebra into the spinal canal (approximately 1 - 5 mm). This condition is called disc protrusion. Over time, the protrusion can turn into a disc herniation.

Causes of disc protrusion

Disk protrusion occurs against the background of metabolic disorders , in the presence of hereditary features of the structure of the spine, after suffering infectious diseases, with incorrect posture and underdeveloped muscle corset, with heavy physical exertion, sharp turns of the body, injuries, falls, etc. Disc protrusion can occur with osteochondrosis of the spine .

How does a protrusion of a disc proceed?

Disk protrusion causes narrowing of the spinal canal, compression of the nerve roots and membranes spinal cord, inflammation and swelling of the surrounding tissues. The person feels severe pain in the region of the protrusion of the disc and along the nerves extending from the spinal cord. In addition, the pain will be in the area that the pinched nerve innervates, here the coordination of movements and muscle strength may be disturbed.

Symptoms of the disease depend on the size of the protrusion and its location. So, with protrusion of the lumbar spine, numbness in the groin and pain in the lumbar region first appear. Then numbness of the toes may appear, the pain spreading from top to bottom along the back of the leg. Protrusions of the lumbar and thoracic spine respond well to treatment.

The presence of protrusion in the cervical spine can lead to rapid disability of the patient. Such a protrusion rarely gives pain in the neck, dizziness, headache, jumps appear more often. blood pressure, pain in the shoulder, pain in the arm, numbness of the fingers.

Diagnosis of disc protrusion

In addition to examining a specialist to confirm the diagnosis, it is also carried out instrumental diagnostics. On an x-ray of the spine, bone changes in the spine will be visible; when performing computed tomography (CT), in addition to changes in the bone tissue, you can see changes in soft tissues, but they are not clearly visible, so CT is often combined with myelography (X-ray of the spine after the injection of a contrast agent into the spinal canal). And best of all, changes in the bone and soft tissues of the spine are visible during magnetic resonance imaging (MRI).

Functional diagnostic methods are also carried out, which allow to identify the disease at an early stage. So, with electromyography, the functions peripheral nerves, neuromuscular junctions and muscles. Based on this study, one can judge the conductive capacity of nerve fibers.

Treatment of disc protrusion

Treatment of disc protrusion can be conservative and operative. Currently, preference is given to conservative methods of treatment, and only if they are completely ineffective, surgical treatment is performed.

Conservative treatment is a set of measures to relieve pain and swelling of the surrounding tissues, restore the function of the spine, movements and sensitivity in the affected areas.

First, fixation and traction of the spine is performed to relieve the load on the modified disc. Simultaneously conducted drug treatment in order to eliminate edema and inflammation, and then complexes are added physiotherapy exercises, massage, reflexology (Chinese method of treatment - exposure to special points on the surface of the body),

V.N. Karp, Yu.A. Yashinina, A.N. Zabrodsky
5th Central Military Clinical Hospital of the Air Force, Krasnogorsk, Moscow Region
An important symptom of disc degeneration is the "vacuum phenomenon" or "vacuum effect", manifested by the presence of gas bubbles of various sizes in the thickness of the disc. The gas inside the disk has mixed composition dominated by nitrogen. Disk protrusions are often absent.
The accumulation of gas in the intervertebral discs is usually detected by computed tomography (CT). This feature is poorly visualized in MRI, due to the physical basis of the method. At CT, the "vacuum phenomenon" is manifested by foci of air density (from -850 to -950 N) with clear contours. When changing the position of the body and the load on the spine, it does not disappear.

Rice. 1. CT scan of the lumbosacral region (L5-S1). In the disc L5-S1, a gas cavity is visualized - the "vacuum effect", as well as the accumulation of gas in the epidural space on the right.


Rice. 2. MRI of the lumbosacral region: epidural accumulation of gas at the level of the L5-S1 disk looks like a soft-tissue volumetric formation (corresponding to adipose tissue in density), squeezing the dural sac and root, the vacuum effect is visualized only in the disk structure. Long-term observation of such patients shows the impossibility of a significant reduction in the severity of the "vacuum phenomenon". Some authors indicate that a similar accumulation of gas in the epidural space can be observed with a herniated disc and is an indirect sign of rupture of the posterior longitudinal ligament. In these situations, the gas aids visualization of the mass because the protrusion itself is poorly differentiated.
In the literature, we did not find a description of neurological symptoms caused by the accumulation of gas in the epidural space ("gas cyst") in the absence of sequesters of disc herniation, which was confirmed intraoperatively.
We present our observations.
Patient M., born in 1954, was admitted to the neurosurgical department of the 5th Central Military Clinical Hospital of the Air Force with complaints of weakness in the legs, numbness in both feet and burning in them, constant moderate pain in the lumbosacral spine, radiating to both legs, more to the left. For the first time, pain in the lumbosacral spine occurred about 11 years ago after physical activity. Outpatient and inpatient treatment with a positive result. Since December 2004 without apparent reason began to notice increased pain in the lumbosacral spine, radiating to the legs. Gradually developed numbness and weakness in the feet.
AT neurological status- hypoesthesia on the outer edge of both feet. Knee reflexes of normal liveliness, uniform, Achilles - are not called. Moderate weakness in plantar flexion of both feet. Lasegue's symptom on the left from an angle of 45°, on the right - from 65°.
A CT scan on August 24, 2005 (Fig. 1) visualized a gaseous cavity in the L5-S1 disk - the "vacuum effect". In the epidural space at the same level, on the right, there is an accumulation of gas measuring 15 x 10 mm; paramedianally, on the left, there is a subligamentous soft tissue component with inclusions of small gas bubbles. An MRI scan of the lumbosacral region dated August 26, 2005 (Fig. 2) shows an epidural accumulation of gas at the level of the L5-S1 disk that looks like a soft-tissue mass (corresponding to adipose tissue in density), deforming the dural sac.
Considering clinical manifestations, as well as CT and MRI data, the diagnosis was made: osteochondrosis of the lumbosacral spine, complicated by protrusion of the L5-S1 disc with accumulation of gas in the spinal canal (epidurally and subglottically), epidural fibrosis with compression of the roots of the cauda equina.
On September 13, 2005, the operation was performed: interlaminar meningoradiculolysis of the S1 root on the left, opening of the subglottic "gas cyst".

Rice. 3. CT scan of the lumbosacral spine on the disc and spinal canal.

No sequestration was detected during the operation. The dural sac and S1 root are surrounded by dense epidural tissue and are fixed by adhesions on the disc and do not move. Performed meningoradiculolysis. After separation of the adhesions on the ventral surface of the dural sac and root, the latter was displaced medially. Disc moderately bulges, stony density. The posterior longitudinal ligament is ossified and covered with scar-modified epidural tissue, which is excised. When dissecting the posterior longitudinal ligament, gas bubbles were released, the tension of the ligament decreased. Revision of the spinal canal in the caudal and cranial directions and along the root did not reveal any mass formations. The spine is free, easily shifted.
In the postoperative period, regression of neurological symptoms was noted. Discharged on the 10th day after surgery with improvement.
Patient G., aged 47, was admitted to the department with complaints of pain in the lumbosacral spine, radiating to the left leg along the posterior-outer surface, aggravated by movement.
In the neurological status: decreased strength of the plantar flexion of the left foot, deep reflexes of average liveliness, equal, except for the Achilles and plantar reflexes on the left, which are depressed. Hypesthesia in the zone of innervation of L5 and S1 roots on the left. Lasegue's symptom on the right - 60°, on the left - 50°. Weakness of the muscles of the left buttock. Percussion and palpation of the spinous processes and paravertebral points are painful at the level of L4-5 and L5-S1 on the left, there is also muscle tension. Movement in the lumbar region is limited due to pain. When walking, he limps on his left leg.
History of surgery - interlaminar removal of sequesters herniated disk L5-S1 on the right-va (December 1992). Postoperative period smooth. Pain in right leg and the lumbosacral spine were not disturbed.

level of the L5-S1 segment with a vacuum effect in the intervertebral
The above complaints appeared a month before the current hospitalization after lifting weights. Conservative treatment without effect. 2 weeks before hospitalization, frequent urination appeared.
On CT scan in the L4-5 segment, there is a posterior circular protrusion up to 2-3 mm with lateralization to the left half of the spinal canal and the left lateral foramen. The spine is thickened at this level. In the L5-S1 segment, pronounced degenerative changes - intervertebral disc significantly reduced in height, gas bubbles are determined in its structure - the "vacuum effect" (Fig. 3). In addition, a gas bubble is located in the left half of the spinal canal in the projection of the left nerve root under the posterior longitudinal ligament, deforming the anterior-left contour of the dural sac, squeezing the nerve root. Signs of spondylarthrosis are determined.
The patient was diagnosed with osteochondrosis, spondyloarthrosis of the lumbosacral spine, complicated by accumulation of gas in the subglottic space with compression of the S1 root and L5 radicular syndrome on the left. Condition after interlaminar removal of sequesters of L5-S1 disc herniation on the right (1992).
A comprehensive conservative treatment. The effect was not obtained, the clinic of S1 root compression on the left and L5 radicular syndrome on the left remained.
05/06/04 operation - L5 hemilaminectomy on the left, opening of the subglottic gas cavity (cyst), compressing the root and dural sac, meningoradiculolysis of S1 and L5 roots. When dissecting the posterior longitudinal ligament, which was the wall of the gas cyst, gas bubbles were released without color and odor. Ligament sunk, compression of the root and dural sac is eliminated. The postoperative period is smooth, the wound healed by primary intention. Continued conservative therapy. The condition improved, regression of radicular syndrome. The movements in the limbs are preserved, the strength and tone are good, he walks freely, the background of the mood has increased.
In a satisfactory condition, he was discharged under the supervision of a neurologist at the place of residence. A follow-up examination and a course of inpatient conservative treatment were recommended. rehabilitation treatment after 6 months in neurosurgical department 5 CVCG Air Force, but the patient did not arrive.
conclusions
1. "Vacuum phenomenon" in the disc may be accompanied by accumulation of gas under the posterior longitudinal ligament, causing compression or irritation of the roots, which requires surgical intervention.
2. Accumulation of gas epidurally or subglottically is not always accompanied by a disc herniation.
3. With MRI, the "gas cyst" is poorly visualized, which is due to the physical basis of the method and can be mistaken for a sequestered disc herniation.
4. The method of choice for diagnosing an epidural "gas cyst" is computed tomography.

NEUROSURGERY, № 3, 2008

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