Will lumbar disc herniation recur frequently? What is the recurrence rate? How to pay attention to protection?

Lumbar disc herniation and its secondary nervous system abnormalities are the focus of clinical multidisciplinary research. In recent years, the study of its pathogenesis has promoted the improvement of clinical treatment. The research progress and clinical treatment status of lumbar disc herniation are summarized as follows.

First, the mechanism of lumbar disc herniation

1, lumbar intervertebral disc degeneration

Lumbar disc degeneration is an important cause of lumbar disc herniation. The degeneration of the spine in the population is extremely unbalanced, and some lumbar disc degeneration began in youth. The incidence of lumbar disc herniation in these people is very high. It is generally believed that lumbar disc degeneration is caused by the dynamic load of lumbar disc.

Adams et al. carried out exercise load test on cadaver spine, and simulated slow walking found that the static pressure in nucleus pulposus decreased 13 ~ 36%. The ability of intervertebral disc as a hydrostatic "buffer" depends on the water content in the nucleus pulposus. Nucleus pulposus is like a sealed hydraulic system. When the volume increases, the liquid pressure increases, and when the volume pressure decreases, the liquid pressure decreases. A pressure equal to body weight can expel 10 ~ 15% of the water in the intervertebral disc of the corpse within 4 hours. Magnetic resonance imaging showed that the volume (water content) of lumbar intervertebral disc decreased by 20% after one day's exercise. After the nucleus pulposus loses water, the pressure decreases, and the pressure on the intervertebral disc will be transferred to the annulus fibrosus. Highly concentrated pressure will destroy the fiber ring structure and lead to the formation of cracks.

Other biological studies show that the distribution of elastic coefficient of normal intervertebral disc is uniform and symmetrical, while the elastic coefficient of degenerated intervertebral disc ring fiber is the lowest in the posterior part, and lumbar disc herniation often appears in the posterior part in clinic, which may be related to the pathogenesis of lumbar disc herniation. The internal mechanics of intervertebral disc depends on load history and applied load, and the latter has an influence on intervertebral disc degeneration.

The nucleus pulposus of lumbar intervertebral disc is mainly composed of glycoprotein, and the fibrous ring is composed of collagen. In articular cartilage, matrix metalloproteinase -3 can decompose glycoprotein and collagen, leading to matrix destruction. Metalloproteinase-1 specifically binds to MMP-3 to inactivate it. Masakani et al. found that most samples were MMP-3 positive and MMP-1 negative by immunohistochemical staining of surgically removed intervertebral discs. It is believed that MMP-3 positive and metal imbalance lead to glycoprotein decomposition, emptying the water content in nucleus pulposus and causing intervertebral disc degeneration. In the process of intervertebral disc degeneration, the metabolic changes of intervertebral disc tissue are caused by dynamic pressure and MMP-3 production. In order to clarify the mechanism of lumbar intervertebral disc degeneration, it is necessary to clarify the exact mechanism of how MMP-3 and MMP-1 act on normal or degenerative intervertebral discs. This research may use some drugs to treat and prevent the degeneration of lumbar intervertebral disc.

2. Lumbar disc herniation causes non-bacterial inflammation and immune response.

Lumbar disc herniation is often accompanied by non-bacterial inflammatory reaction. As a biochemical or immune stimulus, the prominent lumbar intervertebral disc substance can cause clinical symptoms of patients. Mccarron injected a uniform sample of nucleus pulposus into the epidural space of dogs and compared it with normal saline. Under the microscope, severe inflammatory reaction could be found. Wliiburger found an increase in prostaglandin level in fragments of cultured lumbar intervertebral disc samples, and Saal found a high activity of phospholipase A2 in lumbar intervertebral disc extracts. This enzyme is the rate-limiting enzyme for the production of prostaglandin and interleukin by cells in inflammatory sites. It can be speculated that once this enzyme is released from the restriction of intervertebral disc, it can contact nerve roots, produce nerves through the action of phosphate in nerve cell membrane or cause inflammation through inflammatory mediators produced by the enzyme, and act on nociceptors in fibrous ring or epidural space to produce clinical symptoms.

Further study found that the level of prostaglandin in free lumbar intervertebral disc was higher than that in protruding lumbar intervertebral disc, and the level of prostaglandin in protruding lumbar intervertebral disc was the lowest. The prostaglandin level of lumbar intervertebral disc in straight leg elevation test is higher than that in negative protrusion. Prostaglandin is one of the strongest natural inflammatory mediators and plays an important role in the regulation of cell function. Prostaglandins regulate the inflammatory effect of lumbar disc herniation, especially in the radiation symptoms caused by straight leg elevation. Moreover, the complete fibrous ring can provide isolation and protection for inflammatory stimulation caused by lumbar disc herniation.

Takahashi found that inflammatory cell peptides in the tissue of herniated lumbar intervertebral disc obtained during operation include interleukin-1α(IL- 1α) and tumor necrosis factor -α(TNF-α). IL- 1α and TNF-α make tissues and cells produce prostaglandins, which can cause pain or promote nerve sensitivity to other pain-causing substances. These findings increase the possibility that inflammatory cytokinins (including IL-α and TNF-α) are produced in the herniated intervertebral disc tissue, which leads to prostaglandin production by the tissue cells constituting granulation tissue, leading to sciatica. Kang et al. cultured the herniated lumbar intervertebral disc obtained by operation for 72 hours, collected the culture medium for biochemical analysis, and compared it with the lumbar intervertebral disc obtained by scoliosis surgery. The results showed that MMP-3, IL-α and NO were significantly higher than those in the control group.

The evidence of vascular endogenesis, granulation and fibrous tissue proliferation in surgical resection of lumbar intervertebral disc has been established. Some data show that the nucleus pulposus protrudes into the spinal canal and the repair process occurs through normal inflammatory reaction. If the contents of the nucleus pulposus are considered "foreign", this may lead to chronic inflammatory reaction. Inflammation and neovascularization caused by protrusions can cause phagocytosis and absorption.

In vitro cell culture and biological examination of surgically excised herniated intervertebral disc, Doita found that granulation tissue with angiogenesis appeared endogenously at the edge of fibrocartilage fragments. Anti-interleukin-ⅰ, intracellular adhesion molecule-ⅰ, lymphocyte-related functional antigen and basic fibroblast growth factor are expressed on monocytes, which penetrate into the prominent intervertebral disc and cause neovascularization and inflammation. Lumbar intervertebral disc is the largest avascular unit in adults. The appearance of new blood vessels and inflammatory cells in the herniated lumbar intervertebral disc shows that mechanization is not the main process of the development of the herniated lumbar intervertebral disc, but mainly the absorption process in the healing stage. This may be an explanation that affects the natural disappearance or reduction of lumbar intervertebral disc protruding in spinal canal and the relief of symptoms without surgical treatment.

Studies have shown that the humoral immunity and cellular immunity of patients with lumbar disc herniation are abnormal. Zhang Qiang et al. measured the cerebrospinal fluid and serum immunoglobulin in patients with lumbar disc herniation and normal controls by radioimmunoassay. The results showed that with the aggravation of lumbar disc herniation, the cerebrospinal fluid and serum immunoglobulin of patients also increased gradually. Convex type only causes the increase of immunoglobulin in cerebrospinal fluid, while ruptured type and free type can cause the increase of cerebrospinal fluid and serum. The possible mechanisms are as follows: ① The nerve root suffers from mechanical compression of intervertebral disc herniation and autoimmune inflammatory changes, which can lead to the destruction of blood-brain barrier, the increase of capillary permeability in nerve root and the infiltration of plasma protein into cerebrospinal fluid; (2) Collagen ⅰ and ⅱ in intervertebral disc tissue, glycoprotein is a potential autoantigen, which can stimulate the body to produce delayed hypersensitivity T lymphocytes and cytotoxic T cells mediated cellular immune response, leading to early degeneration of intervertebral disc, and under the constant action of T, B lymphocytes and intervertebral disc antigen, it produces immune response, which is manifested by the increase of blood immunoglobulin; ③ Demyelinating substances and intervertebral disc antigen substances caused by nerve root injury can stimulate immunocompetent cells in the central nervous system to produce immunoglobulin. Therefore, it is considered that the immune inflammatory changes of nerve roots are an important cause of sciatica, and surgical treatment of lumbar disc herniation can not only relieve the mechanical compression of nerve roots, but also interrupt the immune response caused by intervertebral disc tissue.

3. Mechanical compression caused by lumbar disc herniation

1934, Mixter and Barr pointed out that the tissue of lumbar intervertebral disc protrudes into the spinal canal, and the nerve roots are stimulated, causing sciatica. For decades, this concept has been widely accepted and formed the neuroanatomical basis of lumbar disc herniation. When the posterolateral disc herniation can invade the posterior root ganglion. Smith found that when the straight leg is raised, the spinal nerve root can move 2~5mm in the intervertebral foramen. If nerves are restricted or involved, this normal movement may be restricted. When the nerve tries to stretch and deviate from its movement process, it will stimulate and inflame the nerve root. With the slow compression of nerve, vein injury occurs first, then capillary and finally artery injury. Mechanical compression of spinal nerve causes sensitive changes of somatic evoked potentials, and the compression time is significantly related to the decrease of amplitude and the extension of latency.

Cohen et al. studied the human ponytail anatomically, and confirmed by nuclear magnetic resonance (NMR) that the nerve roots in the ponytail were arranged in a very orderly and symmetrical layered arrangement. At L5S 1 level, the last nerve component in cauda equina dural sac is S5 nerve root, followed by S4, S3, S2 and S 1. After the component of L4-5 is further pushed, the L5 nerve root enters the anterior side. In any case, the sports fiber component is in the front, and the larger fullness component is in the back. The two are always adjacent and positioned at a small angle. This position appears strictly in the posterior root ganglion. For a nerve root or cauda equina, it appears uneven in the posterior root ganglion. Uneven compression of one nerve root or cauda equina can lead to asymmetric compression of sensory or motor components of one or more adjacent nerve root components. This increases the complexity of clinical symptoms, and may lead to differences in clinical manifestations between patients and changes in clinical symptoms of the same patient at different times. In a word, it is considered that the mechanical compression of the prominent lumbar intervertebral disc and the chemical stimulation of the substance of the prominent lumbar intervertebral disc are the causes of sciatica.

Second, the treatment of lumbar disc herniation

No matter in the past or now, only about 10% of patients with lumbar disc herniation need surgery. Generally, conservative treatment does not exceed three months, and surgery will be considered if it fails. Therefore, non-surgical treatment is the basic treatment of this disease. Non-surgical treatment of lumbar disc herniation includes bed rest, traction, massage, acupuncture, injection therapy, chemonucleolysis and percutaneous discectomy. Non-surgical therapies commonly used in clinic include epidural injection, chemonucleolysis and percutaneous discectomy.

1, epidural injection therapy

Epidural injection is an important non-surgical treatment for lumbar disc herniation, which has a history of nearly 100 years. Viner dissolved 20 ml 1% procaine in 50- 100 ml ringer's solution and injected it into epidural space through sacral canal to treat sciatica. 1953, Lievre injected hydrocortisone into epidural space to treat low back pain, and began the treatment of injecting glucocorticoid into epidural space.

Coomes compared the curative effects of 20 bedridden patients and 20 cases of epidural injection of local mahjong drugs on lumbosacral radiculopathy. The results showed that 12 patients in the epidural injection group had improved their neurological signs (straight leg elevation, spinal mobility, muscle strength and reflex), while only 5 patients in the bed rest group. The average recovery time of epidural injection group was 1 1 day, which was significantly shorter than that of bed rest group (3 1 day). Further research shows that glucocorticoid plus local anesthetic is superior to simple injection of local anesthetic. The clinical symptoms of most patients (96%) improved within 6 days after epidural injection of glucocorticoid, and local anesthesia was effective 1 1 day after epidural injection, but it took 1~4 weeks to relieve the symptoms in bed. Injecting glucocorticoid into epidural space to treat radicular pain, most reports show that 60% patients have good effect.

In recent ten years, lumbar disc herniation has a trend of non-surgical treatment. It is found that the fragments of lumbar disc herniation can be absorbed by themselves without surgery, and there is lumbar disc herniation without clinical symptoms. Discogenic low back pain and nerve root pain can also occur without disc herniation. These findings indicate that inflammatory reaction is the root cause of these manifestations. This provides a theoretical basis for epidural injection of drugs and makes this treatment widely used.

Glucocorticoid has anti-inflammatory properties and membrane stability by inhibiting prostaglandin synthesis, neuropeptide synthesis and blocking phospholipase A2 activity. Injection of local anesthetic can interrupt the persistent nerve activity that produces pain, relax muscle spasm and eliminate the accompanying reflex sympathetic dystrophy.

Epidural injection for the treatment of lumbar disc herniation includes single administration, continuous administration of epidural catheter and PCA. The route of administration includes epidural injection through sacral canal and posterior median puncture. Accidentally entering the subarachnoid space through the puncture of the posterior median epidural space can cause arachnoiditis and even permanent paralysis. Generally, the incidence of penetrating dura mater is 0.27~0.6%, so the incidence of total spinal anesthesia is 0.2%. These complications limit the wide use of this puncture method.

Up to now, there are few good controlled studies on epidural injection in the treatment of lumbar disc herniation. There is no consensus on what is appropriate epidural glucocorticoid injection. The existing literature fails to explain that there are no unified standards for the most effective route of administration, the types and doses of glucocorticoids, the concentration and dose of local anesthetics, the number of injections, the injection time and the evaluation of the results.

In the study, the author found that under the guidance of X-ray, the contrast agent can be diffused and developed in the epidural space through vertical puncture near the lumbar vertebrae and injection near the intervertebral foramen. Therefore, epidural injection can be divided into three ways: epidural injection through sacral canal, epidural injection through posterior median and epidural injection through paravertebral foramen. In the control study conducted by the author, the effect of epidural injection through intervertebral foramen in the treatment of lumbar disc herniation is better than that through retromedian epidural injection, because the liquid injected by the former can not only act on nerve roots, but also directly reach around the inflammatory focus caused by intervertebral foramen, which can effectively eliminate inflammation and avoid complications caused by retromedian epidural puncture.

After a single epidural injection of 25mg prednisolone, the blood cortisol was significantly higher than that of the control group on the second day after administration, but it quickly returned to normal on the fourth and sixth days after administration. Therefore, once a week, each injection of 25mg prednisolone can avoid complications caused by glucocorticoid and effectively eliminate inflammation. The author used Mailuoning (a traditional Chinese medicine preparation) instead of prednisolone to treat lumbar disc herniation, and achieved satisfactory results, providing a more reasonable drug for patients who are not suitable for glucocorticoid such as diabetes and tuberculosis. Epidural injection can effectively eliminate the inflammatory reaction caused by lumbar disc herniation and relieve clinical symptoms. However, well-designed controlled studies are needed to standardize this treatment.

2. Percutaneous lumbar discectomy

Percutaneous lumbar discectomy is a new technique developed in recent decades, and its success rate is 70 ~ 94%. Compared with traditional surgical methods, it has the advantages of less trauma, quick recovery, no interference with spinal canal structure, no influence on spinal stability, few complications, simple operation and so on, and the curative effect is satisfactory. It is generally believed that percutaneous lumbar discectomy can significantly reduce the internal pressure of intervertebral disc, significantly reduce the damage to nerve roots and eliminate the release of inflammatory chemicals after drilling fibers and removing a certain amount of nucleus pulposus.

Its complication is discitis, the incidence rate is 65438 0%, and it can be cured by non-surgical treatment. Nerve root injury, mainly contusion, gradually recovered after 1~2 months. Hematoma of psoas major rarely occurs, but it can heal itself after 1~3 months.

Due to the limitation of technology and conditions in China, this treatment method is far from universal, and further research and development are needed.

3. Chemolysis of Medullary Nucleus

Since Simith first reported the treatment of lumbar disc herniation with chymopapain in 1964, chemonucleolysis of medullary nucleus has become a remarkable method for the treatment of lumbar disc herniation and has developed rapidly. The reports of early nervous system complications and allergic reactions are a heavy blow to chemonucleolysis therapy. In 1974, the US Food and Drug Administration no longer allows chymopapain as a treatment. However, it soon proved that the neurological complications were caused by surgical errors, and allergic reactions could be avoided by carefully asking medical history and allergic tests. In fact, the allergic reaction has dropped from 0.5% to 0.25%. 1982 after years of debate and research, the us food and drug administration approved the use of this drug. According to the results of double-blind study, it is considered that chemonucleolysis therapy with chymopapain is safe and effective. No deaths or serious complications have been reported since 1987. The treatment of prominent nucleus pulposus with chymopapain has stood the test of time and proved that 30 years of clinical practice is successful. The therapeutic mechanism is that the enzyme cleaves mucopolysaccharide from proteoglycan, releases water in nucleus pulposus, and the prominent nucleus pulposus is dehydrated and atrophied.

Javid prospectively studied 100 patients undergoing chemonucleolysis and 100 patients undergoing laminectomy. Six weeks later, the clinical results showed that 92% of laminectomy patients and 82% of chemonucleolysis patients were successful. Six months later, 88% of chemolysis patients and 85% of laminectomy patients were successful. After 1 year, 87% of chemonucleolysis patients and 82% of laminectomy patients were successful. More patients with chemonucleolysis participated in this work.

At home, due to the immature drug and technical conditions, this technology is far from universal, and it needs long-term exploration and development.

To sum up, mechanical compression caused by lumbar disc herniation and inflammatory reaction caused by chemical release are the causes of clinical low back pain and radiculopathy. Injection of glucocorticoid local anesthetic solution into epidural space can effectively eliminate the inflammatory reaction caused by lumbar disc herniation and effectively treat lumbar disc herniation. However, further research is needed to clarify the pathogenesis of lumbar disc herniation and formulate a standardized method for epidural injection to treat lumbar disc herniation. In China, percutaneous lumbar discectomy and chemonucleolysis have not been widely used to treat lumbar disc herniation, and epidural injection is still an important method for non-surgical treatment of lumbar disc herniation.