I. Definition: Cervical spondylosis is called cervical spondylosis when the cervical disc degeneration itself and its secondary changes irritate or compress the adjacent tissues and cause various symptoms and signs. Through the analysis and comprehensive observation of the whole process of cervical spondylosis, it has been shown that the disease mainly originates from the degenerative changes of the cervical disc.
Overview of the pathogenesis of cervical spondylosis
(I) Pathogenic factors (primary and secondary factors)
The occurrence and development of cervical spondylosis depends mainly on degenerative changes under the condition of congenital developmental spinal stenosis, while other factors including strain, deformity, trauma and inflammation can be regarded as predisposing factors or secondary factors.
(ii) Pathogenesis
The main cause of this disease is the degenerative changes of the intervertebral disc. According to the degeneration process of the intervertebral disc and its subsequent development, the pathogenesis can be divided into two stages.
1. Early stage Disc degeneration and displacement of vertebral segments
Disc degeneration → nucleus pulposus herniation or prolapse → stimulation of local sinus nerve (cervical symptoms appear) → irritation or compression of spinal nerve roots and/or spinal cord → posterior longitudinal ligament and periosteal tear → ligamentous disc space → local traumatic reaction and hematoma formation.
2. Late —- bone spur formation (osteophyte) stage
(1) The formation of bone spurs is an inevitable product of intervertebral disc degeneration to a certain degree, indicating that the degeneration of the cervical spine has reached a stage that is difficult to reverse. The characteristics of pathological changes in this stage are as follows: ligament-disc interstitial hematoma (subperiosteal hematoma) → mechanization, calcification, ossification → formation of bone superfluous (bone spur) on both sides of the barbels and the posterior superior edge of the vertebral body → causing a series of secondary changes
(2) The principles of treatment in this period are
① Asymptomatic people should pay attention to the prevention of various factors that can increase degeneration and induce disease.
(2) The principles of treatment at this stage are: ① Asymptomatic people should pay attention to the prevention of various factors that can increase degeneration and trigger the disease.
(3) Surgery can only remove the bone spur to promote the establishment of a new local equilibrium relationship, but cannot completely change the pathological results caused by degeneration of the affected joint.
C. Classification and treatment procedures of cervical spondylosis
(A) Cervical cervical spondylosis
1. Diagnostic criteria.
1) Clinical features: complaints of abnormal sensation such as pain in the neck, shoulder and occipital area, accompanied by corresponding pressure points and a stiff neck.
2) Imaging changes: straightening of cervical curvature or mild trapezoidal changes on X-ray lateral radiographs, MR imaging showing disc degeneration or posterior protrusion signs.
3) Excluding other disorders: mainly excluding cervical sprain, frozen shoulder, rheumatic myofibrositis and other non-cervical origin of neck and shoulder pain.
2. Treatment principles.
1) Avoid and eliminate various triggering factors: pay attention to sleep and working position, avoid long-term neck bending, head and neck trauma, strain and cold stimulation.
2) Non-surgical therapy is the main treatment, physical therapy, massage, external use of neck circumference, light weight (1-1.5kg) traction therapy, etc. can make the symptoms relieved. In the acute stage, interspinous and paraspinous nerve block therapy is more effective.
(B) Nerve root type cervical spondylosis
1.Overview: This type is second only to the former and is more common clinically, mainly manifesting sensory, motor and reflex disorders consistent with the distribution area of spinal nerve roots.
2. Diagnostic criteria: mainly based on the following five points.
1) The typical root symptoms (numbness, pain) are consistent with the area innervated by the cervical spinal nerve.
2) The cervical compression test and upper limb pull test are mostly positive.
3) X-rays can show abnormalities such as changes in cervical spine curvature, non-concealed vertebral segments and bone spur formation, while MR imaging clearly shows the local pathological anatomy, including nucleus pulposus protrusion and prolapse, and the site and extent of spinal nerve root involvement.
4) The clinical manifestations are consistent with the abnormal imaging findings at the segmental level.
5) Substantial cervical skeletal lesions (tuberculosis, tumor, etc.), thoracic outlet syndrome, carpal tunnel syndrome, ulnar nerve, radial nerve and median nerve injury, periarthritis of the shoulder joint, tennis elbow and biceps tenosynovitis, and other disorders with upper extremity pain should be excluded.
3.Treatment principles
1) Non-surgical treatment Various targeted non-surgical treatments have obvious efficacy, among which continuous (or intermittent) traction of head and neck, cervical braking and correction of poor posture have certain efficacy, and the application of nerve block therapy in the acute stage has obvious effect. In cases of nucleus pulposus protrusion and prolapse, the clinical manifestations are consistent with the imaging of the spinal nerve root involvement in the segment, and collagenase lysis therapy can be considered if regular non-surgical therapy is ineffective for more than 3 months.
2) Surgical treatment Surgery can be considered for anyone with progressive muscle atrophy and neurological dysfunction. In cases with vertebral segment instability or root canal stenosis, internal fixation of the intervertebral interface can also be used at the same time to open up the vertebral segments and fix the fusion. Although the posterior cervical approach to decompression through incision of small joints is effective, it has been gradually abandoned because of the postoperative tendency to cause angular deformity of the cervical spine.
4.Prognosis
1) Most of the cases caused by simple cervical nucleus pulposus protrusion have a good prognosis, and there are few recurrences after cure.
2)Those whose nucleus pulposus has formed adhesions are prone to residual symptoms.
3) For those who are caused by hyperplasia of the hook vertebral joint, the prognosis is more satisfactory with early and timely treatment. If the disease is longer and subarachnoid adhesions have formed at the root canal, the symptoms are less satisfactory due to prolongation.
4) Patients with extensive osteophytes are not only complicated to treat, but also have a poor prognosis.
(C) Spinal cord type cervical spondylosis
1. Overview: Although it is less common than the first two, it is in an important position among all types because of its serious symptoms and its development in the form of “hidden invasion”, which can be easily misdiagnosed as other disorders and delay treatment. Because it mainly compresses or stimulates the spinal cord and causes spinal nerve sensory, motor, reflex and defecation dysfunction, it is called spinal cord cervical spondylosis.
2.Diagnostic criteria
The diagnosis of this type is mainly based on.
(1) Clinical manifestations of spinal cord compression, with the cone bundle sign being the main feature. The order of arrangement of the pyramidal tracts in the medulla is cervical, upper extremity, thoracic, lumbar, lower extremity and sacral nerve fibers in the order of inward and outward, which are divided into the following three types depending on the location of the nerve fiber involvement.
Central type (also called upper extremity type): It is called central type because the deep part of the pyramidal bundle is involved first, because the nerve fiber bundle is close to the central canal; the symptoms start from the upper extremity first, and then spread to the lower extremity. The pathological changes are mainly due to compression or irritation of the sulcus arteriosus; if one side is compressed, the symptoms appear on one side; if both sides are compressed, the symptoms appear on both sides.
② Peripheral type (also known as lower limb type): refers to the pressure first acting on the surface of the cone bundle and the lower limbs first appear symptoms, when the pressure continues to increase and deep fibers, then the symptoms extend to the upper limbs, but the degree is still heavier than the lower limbs. The mechanism is mainly the result of direct compression of the anterior wall of the dural sac by the anterior canal bone or the prolapsed nucleus pulposus.
(3) Anterior central vascular type (also known as extremity type): that is, the upper and lower extremities at the same time. This is mainly caused by the involvement of the anterior central artery of the spinal cord, which causes ischemia in the anterior part of the spinal cord through the innervation area of this vessel and produces symptoms. This type is characterized by rapid onset of disease and rapid healing with treatment; non-surgical treatment is effective. The above three types can be divided into mild, moderate and severe according to the severity of symptoms. Mild refers to the early stage of symptoms, although there are symptoms, but can still adhere to work; moderate refers to those who have lost the ability to work, but can still take care of their personal life; if the bed rest, can not go to the ground and lose the ability to take care of their own life, then it is severe. Generally speaking, if the pressure-causing substances are removed early, there is still hope for recovery in severe cases. However, if the spinal cord continues to develop until degeneration or even cavity formation occurs, it is difficult to reverse the function of the spinal cord.
(2) Numbness of the limbs This is mainly due to the involvement of the thalamic tract of the spinal cord. The order of the fibers of this bundle is similar to the former, from the inside out to the cervical, upper extremity, thoracic, lumbar, lower extremity and sacral nerve fibers. Therefore, the location and typing of symptoms are consistent with the former. The distribution of nociceptive and thermo-sensory fibers in the thalamic tract of the spinal cord is different from that of tactile fibers, so the degree of compression varies, i.e. nociceptive and thermo-sensory deficits are obvious, while tactile sensation may be completely normal. This kind of dissociative sensory disorder is easily confused with spinal cord cavitation and should be distinguished clinically.
(3) Reflex disorders The main manifestations are.
① Abnormal physiological reflexes: Depending on the segment of the spinal cord affected by the lesion, there are corresponding changes in each physiological reflex, including the biceps, triceps and radial reflexes of the upper limbs, and the knee reflex and Achilles reflex of the lower limbs, which are mostly hyperactive or active. In addition, the abdominal wall reflex, testicular reflex and anal reflex may be weakened or disappear.
(2) Presence of pathological reflexes: Hoffmann’s sign and palmar chin reflex have the highest positive rate; ankle clonus, patellar clonus and Babinski’s sign may appear in the later stage of the disease.
(4) Defecation and urinary dysfunction Most of them appear in the later stage. At first, urinary urgency, poor emptying, urinary frequency and constipation are common, and gradually urinary retention or urinary and fecal incontinence appear.
(5) Imaging examinations may show various imaging findings such as sagittal narrowing of the spinal canal, vertebral segment instability (trapezoidal changes), osteophytes (bone spur formation), dural sac compression signs and spinal cord signal abnormalities.
(6) Other disorders should be excluded, including amyotrophic lateral sclerosis, spinal cord cavitation, spinal cord consumption, skull base depression, polyneuritis, spinal cord tumor, secondary adhesive spinal arachnoiditis, ataxia, and multiple sclerosis. Note that cases of coexistence of two or more disorders are often found clinically.
(7) Other tests such as cerebrospinal fluid aspiration, electromyography and evoked potentials can be used to assist in the diagnosis and differential diagnosis.
3.Treatment principles
(1) Non-surgical treatment
It is still the basic treatment for this type (the specific method is the same as before), especially the early central type (upper limb type) and the anterior central vascular type (limb type), about nearly half of the cases can obtain more obvious results. However, the disease should be closely observed during the procedure, and any rough manipulation and maneuvers should be avoided. Once the condition worsens, surgery should be performed early to prevent degeneration of the spinal cord.
(2) Surgical treatment
(1), surgical case selection If.
(1) acute progressive cervical spinal cord compression symptoms are obvious and confirmed by clinical examination or other special examinations (MRI, CT scan, etc.), surgery should be performed as soon as possible.
(ii) those with a long duration of disease, with symptoms that continue to worsen and with a clear diagnosis
③ Although the spinal cord compression symptoms are moderate or mild, but no improvement by non-surgical treatment for more than 1-2 courses and affect workers.
2) Surgical approach and procedure Depending on the condition of the patient, the patient’s general condition, the operator’s technical condition and surgical operation habit, the most effective surgical approach and procedure will be selected.
①Surgical approach: for those with cone bundle compression symptoms, the anterior approach should be adopted in principle. For those with sensory disorders and cervical spinal stenosis, the posterior cervical approach is the main approach. For those with both symptoms, depending on the operator’s habit, the anterior or posterior approach should be chosen first, and the need for another approach for decompression should be decided after l to 3 months according to the recovery situation.
②Surgical procedure: for herniated or prolapsed nucleus pulposus, nucleus pulposus removal is performed first, followed by internal fixation, bone graft fusion, or artificial disc implantation as appropriate. For those with spinal cord compression due to bone spurs, accidents may occur by dropping the spinal cord as appropriate.
4.Prognosis
The prognosis is better if the disc is herniated or prolapsed, and there are few recurrences after healing if protection can be paid attention to; the central type responds faster to various treatments and the prognosis is more satisfactory; the sagittal diameter of the spinal canal is obviously narrow with large
The prognosis is worse for those with a significantly narrow sagittal diameter of the spinal canal with large bone spurs or calcification of the posterior longitudinal ligament; the prognosis is worst for those with a disease duration of more than one year and severe disease, especially those with degeneration of the spinal cord; the prognosis is also worse for the elderly, especially those with serious systemic disorders or poor function of major organs (heart, liver, kidney, etc.); the first two should be treated with caution when choosing surgical treatment, and special care is needed when operating.
(D) Vertebral artery type cervical spondylosis
1.Overview
Its incidence is similar to the former, because most of them are caused by vertebral joint instability and are easily cured or improved by non-surgical treatment, so fewer people are hospitalized and operated on. This type is easily confused with a variety of disorders, and the diagnosis is often difficult to confirm before imaging of the vertebral artery. The diagnosis is often a controversial issue among the departments concerned.
2.Pathogenesis
The disease is a syndrome in which the vertebral-basilar artery supply is inadequately supplied with blood due to various mechanical and dynamic factors causing irritation or compression of the vertebral artery, resulting in narrowing and folding of the vessel.
3.Diagnostic criteria
Mainly based on the following points.
(1) Those who have signs of vertebrobasilar ischemia (mainly vertigo) and/or a history of sudden collapse.
(2) Positive rotational cervical provocation test.
(3) Radiographs showing intervertebral joint instability or osteophytes of the hook vertebral joint.
(4) generally have more pronounced sympathetic symptoms.
(5) Excluding ophthalmogenic and otogenic vertigo.
(6) Insufficient blood supply to the basilar artery due to compression of the first segment of the vertebral artery (the vertebral artery before entering the transverse foramen of the 6th cervical vertebra) is excluded.
(7) Excluding neurosis and intracranial tumors.
(8) The diagnosis of this disease, especially the preoperative localization, should be based on MR, DSA or vertebral arteriography; transcranial Doppler, vertebral arteriogram and cerebral hemogram may have reference value.
4.Treatment principles
(1) Non-surgical treatment is the basic treatment for this type, and more than 90% of cases can be treated, especially those caused by cervical instability, and most of them can be cured without leaving sequelae.
(2) Surgical treatment Surgery should be considered only in the following three cases.
(1) Obvious cervical vertigo or sudden collapse with at least 2 episodes.
(2) The non-surgical treatment is ineffective and it affects normal life and workers.
(3) Those who are confirmed by vascular digital subtraction, vertebral artery angiography or MRA.
5.Prognosis
The prognosis of this disease is mostly good, especially if it is caused by vertebral joint instability. The prognosis of cases with severe symptoms treated by surgery
The prognosis is also satisfactory.