The concept of cervical spondylosis is more ambiguous internationally and often conflates multiple cervical spine disorders, such as cervical disc disease, cervical disc prolapse, and vertebral segment hypertrophy. Therefore, in English, there are often different terms such as degenerative disc disease (degenerative disc disease), degenerative cervical spine (cervical degeneration), and cervical spondylosis (cervical joint stiffness). However, in fact, the conditions described are basically similar. According to most of the literature and monographs, cervical spondylosis is more commonly accepted. Therefore, we often use this term to represent cervical spondylosis. The definition of cervical spondylosis is called cervical spondylosis because the cervical disc degeneration itself and its secondary changes stimulate or compress the adjacent tissues and cause various symptoms and signs. Second, the overview of cervical spondylosis domestic understanding of cervical spondylosis since the early 1960s, before that for a long time, the understanding of cervical spondylosis was not sufficient, and even some individual scholars took a negative attitude, basically did not recognize the existence of cervical spondylosis. However, with the progress of clinical medicine, not only orthopedic surgeons, but also neurosurgery, neurology, Chinese medicine, acupuncture, general internal medicine, and physical therapy physicians have found that cervical spondylosis is very common. Especially in recent years, with the extension of the average life expectancy of our people and the improvement of our diagnostic technology, this problem has become more prominent, and cervical spondylosis has become a common and frequent clinical disease. Although this disease is mainly a degenerative disorder, it is related to a variety of factors. First of all, it should be understood that the anatomy of the cervical spine has special characteristics, as it is the smallest in volume but the most flexible vertebral segment in the spine. It has five joints, and in addition to the same two synovial joints and one intervertebral disc as the lumbar spine, it also has a pair of hook joints (also called Luschka joints). The cervical articular joints are relatively horizontal and arranged in a caudal direction. The anterior curve of the cervical disc allows for extension and lateral bending of the cervical spine, and the tangential alignment of the crooked joints and discs with the nerve roots emanating from both sides plays an important role in the generation and development of clinical symptoms. Because of this special anatomical relationship, the condition is complex, and because of the wide variation among individuals, it is easily confused with other disorders, especially those with similar symptoms caused by adjacent tissue lesions. In addition, the vertebral artery and its channel, i.e., the transverse foramen located on the lateral block of the cervical spine, together with the abundant sympathetic postganglionic fibers surrounding the vertebral artery and the various peculiar symptoms that appear with the lesion add to the mystery of cervical spondylosis. As a result, clinicians, not only beginners but also those who have been working for many years, often find the concept unclear. Third, the natural regression of cervical spondylosis (natural history) cervical spondylosis is due to degeneration of the cervical vertebrae, and degeneration is subject to age, and its incidence and degree increase with age, and become more serious. However, cervical degeneration is not the same as cervical spondylosis, and even those with symptomatic cervical spondylosis may heal and cure themselves as the years go by, or, of course, may intensify. But where does the regression go and what percentage of it is in each case? This is the “natural history of cervical spondylosis” that has been the subject of much research in recent years. Zhao Dinglin et al. have observed the follow-up of different age groups. For those who first had symptoms of cervical spondylosis around the age of 30, about 80% of patients did not have any symptoms in the following 10 years, and only 20% of patients had complaints related to cervical spondylosis, of which about 10% lasted for about 2 to 3 years, and less than 1% lasted for more than 10 years. The Gore study also showed similar findings in its follow-up of more than 200 patients with first-onset cervical spondylosis for more than 10 years; nearly 80% of the patients had reduced neck pain and more than half of them had disappeared. Thus, it seems that the self-healing or cure rate of people with initial cervical spondylosis symptoms accounts for the absolute majority, so there is no need to be too nervous once cervical spondylosis symptoms appear. However, China is a large country with a population of more than 1.2 billion, and the absolute number of cases is still considerable and should be taken seriously. Fourth, the etiology of cervical spondylosis is located at the upper end of the spine, between the head, chest and upper limbs, and the cervical spine is the smallest in volume, but the most flexible and most frequently active segment of the spine. Therefore, since birth, as the human body develops, grows and matures, degenerative lesions gradually appear due to various loads, strains and even trauma. Among them, especially the cervical intervertebral disc, not only the degeneration process begins earlier, and is an important factor in triggering or promoting degenerative changes in other parts of the cervical spine tissue. If there is developmental cervical spinal stenosis, it is more likely to develop. The causative factors are described as follows: (a) degeneration of the cervical spine is the main cause of the development of cervical spondylosis, so some people call this disease cervical disc disease, which shows its importance. Among the structures of the cervical vertebrae, degeneration of the intervertebral disc is particularly important and is often regarded as the “culprit”, and a series of pathological anatomical and pathophysiological changes evolve from the degeneration of the intervertebral disc. The factors of cervical spine degeneration are described below. Intervertebral disc degeneration] The intervertebral disc composed of the nucleus pulposus, the fibrous ring and the upper and lower cartilage plates of the vertebral body is a complete anatomical form, so that the upper and lower vertebral bodies are closely connected to ensure the normal physiological function of the cervical spine under the premise of maintaining the normal anatomical state of the cervical spine. If it starts to degenerate, it loses its normal function due to its altered morphology, so that it eventually affects or disrupts the intrinsic balance of the bony structure of the cervical spine and directly involves the mechanical structure of the vertebrae themselves. Therefore, we regard degeneration of the cervical intervertebral disc as a major factor in the occurrence and development of cervical spondylosis. 1. Fibrous annulus Most often starts at the age of 20. In the early stage, it is a transparent degeneration of fibrous tissue, thickening and disorganization of fibers, and gradually cracks or even complete fracture form a fissure visible to the naked eye. The degree of lesion and the direction and depth of fiber fracture are often consistent with the degree of degeneration of the nucleus pulposus, the direction of pressure and intensity. Fibular ring fracture is generally more common on the posterior side, which is not only related to the thicker fibular ring tissue in the front and the posterior position of the nucleus pulposus center point, but also related to the current occupational characteristics, the current increase in white-collar occupations, due to the need to bury the head in the flexed neck position and hard work, especially for a long time, so that the nucleus pulposus is squeezed to the posterior and increase the compressive stress there. Early degeneration of the fibrous ring may be stopped or restored if the causative factors are removed early. On the contrary, once a fissure is formed under continuous pressure, it is difficult to recover due to the lack of good local blood supply, thus providing a pathological and anatomical basis for the posterior protrusion or prolapse of the nucleus pulposus. 2, medullary nucleus This kind of watery and elastic mucin (proteoglosis also translated as proteoglycan) tissue is mostly secondary to the degeneration of the former. It usually appears after the age of 24, but there are also early onset cases. The linear relationship between the decrease in mucin and the water content of the disc causes water loss and loss of water absorption and a corresponding decrease in its volume, which gradually replaces the normal tissue with fibrous tissue, resulting in stiffness of the nucleus pulposus and further changes in its biomechanical properties. In cases of high local load, trauma and strain, the rate of degeneration is accelerated by the increase of pressure in the intervertebral space. On the other hand, the degenerated nucleus pulposus may protrude to the edge along the fissure formed by the annulus fibrosus. At this point, if the fibrous ring is completely broken, the nucleus pulposus may reach the posterior longitudinal ligament or the anterior longitudinal ligament below, and a series of processes such as subligamentous periosteal separation and hemorrhage may be formed. The degenerated and sclerotic nucleus pulposus may also cross the posterior longitudinal ligament fissure and enter the spinal canal. In the early stage, such invasion of the nucleus pulposus into the spinal canal is reversible and can be returned by effective treatment; once adhesions are formed with the tissue in the spinal canal, it is difficult to be returned. 3, cartilage plate degeneration appears later. Early in the degeneration first cause functional changes, so that the role of the translucent membrane as a body fluid nutrient exchange is reduced. When the cartilage plate thinning has formed obvious degeneration, its nourishing effect is further reduced, or even completely disappeared. In this way, the degeneration and aging of the fibrous rings and the nucleus pulposus are intensified. The above three processes are interrelated and mutually constrained, and when the lesion reaches a certain stage, they are mutually causal and form a vicious circle that is not conducive to the recovery of the disease. In the early stage of cervical spondylosis, due to the degeneration of the intervertebral disc, not only the nucleus pulposus, which has lost water and sclerosis, is gradually displaced to the posterior or anterior part of the vertebral joint, but also the ligament and periosteum are separated from the cortical bone around the vertebral body while the local pressure is increased, and the degeneration of the intervertebral disc itself can cause the loosening and abnormal movement of the intervertebral joint. The intervertebral disc degeneration itself can also cause loosening and abnormal activity of the intervertebral joint, thus intensifying the tearing of the ligament and periosteum and accelerating the formation of the ligament-disc gap. The ligament-disc interstitial hematoma is formed when the ligament separates posteriorly from the intervertebral space because of local microvascular tearing and bleeding. This hematoma can directly stimulate the sinus-vertebral nerve endings distributed on the posterior longitudinal ligament and cause various symptoms, and also increase the pressure under the ligament, so that a series of symptoms such as neck discomfort, soreness and heaviness in the head and neck can occur. At this point, if the cervical spine continues to be in abnormal activities and poor posture, the local compressive stress will be greater and constitute a vicious circle, making the condition increasingly aggravated and developing to the next stage. With the formation of a hematoma in the subligamentous space, fibroblasts become active and gradually grow into the hematoma, gradually replacing it with granulation tissue. If new tears and new hematoma formation continue to occur at this space, the same vertebral segment may show a microscopic view of the coexistence of new and old lesions. As the hematoma mechanizes, ages, and deposits calcium salts, it eventually forms a bony bulge (or spur) that protrudes into the spinal canal or into the anterior edge of the vertebral body. This bulge can grow in size and harden through bleeding, mechanization, ossification, or calcification due to repeated local trauma, continuous stretching of the surrounding ligaments, and other factors. Therefore, in advanced cases, the bone superfluous is very hard, especially in those with multiple trauma, it can be like ivory, thus making it more difficult for surgical resection and certainly increasing the chance of risk The formation of bone superfluous can be seen in any vertebral segment, but it is most common in cervical 5-6, cervical 6-7 and cervical 3-4. In terms of the same vertebral segment, the first occurrence is at the hook, followed by the posterior edge of the vertebral body and the anterior edge of the vertebral body. Degeneration of other parts of the cervical spine] Degeneration of the cervical spine is not limited to the intervertebral disc and the adjacent vertebral body edges and hook vertebral joints, but should also include: 1. Small joints Most degeneration occurs after intervertebral disc degeneration resulting in intervertebral body joint instability and abnormal activity. The early stage is superficial cartilage, and gradually spreads to deep and subchondral layers, eventually forming an injurious arthritis. Finally, due to local degeneration and other secondary joint space narrowing and bone spur formation, resulting in the narrowing of the anterior and posterior diameter of the intervertebral foramen and the upper and lower diameter, so as to easily stimulate or compress the spinal nerve roots, and affect the blood flow of the root vessels and the return of the spinal meninges to the nerve branches, so that a series of symptoms appear in the clinic. 2, yellow ligament Most of the degeneration begins on the basis of the first two degenerations. Its early manifestations are ligamentous laxity, and gradually hyperplasia, hypertrophy, and protrusion into the spinal canal. At a later stage, calcification or ossification may occur. Although this secondary lesion is different from that of developmental cervical spinal stenosis, it is also easy to induce or aggravate the symptoms of cervical spondylosis when the neck is elevated and extended, mainly because the ligament is wrinkled and protrudes into the spinal canal, resulting in stimulation or compression of the spinal nerve root or spinal cord. 3, the anterior longitudinal ligament and the posterior longitudinal ligament Its degenerative changes are mainly manifested as fibrous hyperplasia and sclerosis of the ligament itself, and later calcification or ossification is formed and is consistent with the diseased vertebral joint. This phenomenon may be regarded as a natural protective effect of the body. As the hardening and calcification of the ligament can directly play a local braking effect, thus increasing the stability of the cervical spine and slowing down the further development and deterioration of cervical spondylosis. Sagittal diameter and volume reduction of the spinal canal] Due to the aforementioned causes, the internal volume of the spinal canal is reduced, mainly due to the posterior nucleus pulposus, invagination of the posterior longitudinal ligament and ligamentum flavum, and loosening and hyperplasia of the leptomeningeal joint and small joints, which are secondary factors that cause the reduction of the internal volume of the spinal canal and also reduce the sagittal diameter of the spinal canal, thus constituting a direct cause of irritation or compression of the spinal cord and spinal nerve roots. At this time, if there are other limited pathogenic factors. For example, nucleus pulposus prolapse, traumatic displacement of vertebral segments, bone spur formation and other occupational factors may cause or aggravate the symptoms of neurological involvement. (ii) Developmental cervical spinal stenosis is essentially a twin to cervical spondylosis. In recent years, it has been recognized that cervical spinal stenosis with clinical symptoms is an independent disorder. (3) Chronic strain injury 【Overview】 Chronic strain injury refers to a variety of activities that exceed the maximum of the normal physiological range of activity or the local tolerable hourly value. Because it is different from obvious trauma or accidents in life and work, it is easy to be ignored. However, in fact, it is the most important factor in the degeneration of the cervical spine and has a direct relationship to the occurrence, development, treatment and prognosis of cervical spondylosis. The causes of chronic strain injury are mainly from the following three situations: 1. poor sleep position People spend about 1/3 to 1/4 of their lives in bed. Therefore, poor sleep position because of its long duration and in the brain at rest can not be adjusted in time, it is bound to cause the paravertebral muscles, ligaments and joints of the balance disorders. The side with high tension is prone to different degrees of strain due to fatigue, and the imbalance outside the spinal canal and the spinal canal tissue, thus accelerating the degeneration process of the cervical spine. So in the clinic can often be found in many cases of the first symptoms are after waking up. 2, improper work posture A large number of statistical materials show that the incidence of cervical spondylosis is particularly high in certain workloads, not high intensity, but in a sitting position, especially in low head workers, including domestic workers, embroidery workers, office workers, typing scribes, assembly workers on the instrument assembly line and so on. In addition to the strain on the muscles and ligaments at the back of the neck caused by long-term head down, the internal pressure of the intervertebral discs is also much higher than in the normal position in the flexed neck, and can even be more than double. In addition, for the same reason, certain occupations where the head and neck often turn in one direction, such as operating room nurses, traffic police and teachers, are also prone to neck strain injury. 3, inappropriate physical exercise Normal physical exercise can help health, but activities or sports that exceed the endurance of the neck, for example, American soccer (with the head on the ball), human handstand or somersault with the head and neck as a weight-bearing support point, can increase the load on the cervical spine, especially in the absence of proper guidance. Of course, the consequences of head and neck trauma are even more serious if you lose your hand at this point. In addition, certain folk head and neck exercises should not be advocated for those who have degeneration of the cervical spine; otherwise, not only can the degenerative changes of the cervical spine be aggravated, but even accidents can occur, especially for those who have symptoms of spinal cord compression, any exercise activities that increase the amount and frequency of head and neck activities should be completely prohibited to prevent irreversible consequences.