With the popularization and improvement of surgical treatment technology for cervical spondylosis, surgical treatment for cervical spondylosis has been actively carried out in various regions of the country and has achieved relatively good therapeutic results. However, there are still some problems in the surgical treatment of cervical spondylosis, which directly affect the comprehensive curative effect and deserve our attention and solution.
1. Preoperative differential diagnosis of motor neuron disease (representative disease is amyotrophic lateral sclerosis) is the most common type of disease that needs to be differentiated from spinal cervical spondylosis, and the clinical manifestations of the two have certain commonality. Since they often coexist, and the prognosis of the former directly affects the long-term outcome of cervical spondylosis surgery, special attention should be paid. The possibility of combined amyotrophic lateral sclerosis must be considered if the patient presents with significant muscle atrophy (especially predominantly intrinsic hand muscle atrophy), no clear planes of sensory disturbance, and no significant cysto-rectal sphincter dysfunction, which is characterized by multiple spontaneous potentials and high action potentials on electromyography, especially in the intrinsic hand, sternocleidomastoid, sacrospinous, and rectus abdominis muscles. Several studies have shown that surgery itself can exacerbate or accelerate the progression of motor neuron disease. Therefore, patients with combined motor neuron disease should be operated cautiously; for patients who cannot exclude the possibility of combined motor neuron disease, electromyography of sternocleidomastoid muscle or paraspinal muscle of thoracic dorsum should be done for differential diagnosis.
2, the timing of surgery in the clinical work must pay attention to avoid relying solely on CT, MRI examination and ignore the clinical manifestations and comprehensive, systematic neurological examination. You cannot just look at the imaging showing compression of the spinal cord or nerve roots and perform surgery regardless of the clinical manifestations. Neurogenic cervical spondylosis is the most common type in clinical practice. Studies have proven that irritation of the nerve roots by disc degeneration and secondary trauma with inflammatory response, and physical and chemical irritation of the nerve structures by local injury due to segmental instability are the main pathological changes. Therapeutic measures such as improving blood circulation in the tissues surrounding the cervical spine, reducing nerve root edema, and eliminating inflammatory reactions are taken.
Treatment, surgery is required only when the patient presents with the following conditions.
(1) Conservative treatment is ineffective or recurrent;
(2) The symptoms are obvious and seriously affect the patient’s life and work;
(3) Severe nerve root damage is present.
3, the choice of surgical style adequate decompression is one of the key factors to ensure the efficacy of cervical spine surgery. For those who have single segment or two segments of spinal cord compression without spinal stenosis, cervical lordosis or obvious instability, anterior decompression fusion is generally used. Artificial disc replacement can also be used for those without significant degeneration of the intervertebral joints. For spinal cord-type cervical spondylolisthesis with limited spinal stenosis and limited ossification of the posterior longitudinal ligament, subtotal laminectomy can be used. Anterior decompression is a direct decompression and should remove all compressive materials, including herniated discs, posterior spurs, and hypertrophied posterior longitudinal ligaments. In cases where the disc protrudes into the spinal canal, the posterior longitudinal ligament should be incised and the free disc tissue removed. Anterior surgery can also restore the height of the intervertebral space, reconstruct the curvature of the cervical spine, and eliminate segmental instability.
Removal of the leptomeningeal joint is generally not required, although leptomeningeal joint hyperplasia is one of the causes of neurogenic stenosis, the more significant causes are loss of intervertebral space height and disc herniation. The radicular symptoms caused by radicular stenosis can be eliminated by removing the disc and rebuilding the height of the intervertebral space. The use of an intervertebral spacer can be very effective in restoring the height of the intervertebral space, but excessive spreading must be avoided, as this may lead to overloading of the small joints and excessive pressure within the adjacent segmental discs.
Considerations for making decisions about surgical treatment of cervical spondylosis
The surgical treatment of cervical spondylosis requires comprehensive consideration before a good treatment decision can be made, and the author believes that there are nine aspects to consider.
(1) First of all, is there any indication for surgery? For spinal cord type cervical spondylosis, we should choose to operate as early as possible; for neurogenic type, surgery should be considered only if the symptoms are heavy, recurrent, affecting life and work, and the efficacy of regular conservative treatment is not good for 3 months; for clearly diagnosed vertebral artery type and sympathetic type, surgery should also be performed if the symptoms are heavy, recurrent and ineffective by conservative treatment.
(2) Choose the anterior or posterior route? The choice of anterior and posterior approaches for lower cervical spinal cord cervical spondylosis has been controversial for many years. It is generally believed that anterior decompression is appropriate for 1. anterior compression of the spinal cord in one segment; posterior decompression is appropriate for multi-segment compression, especially for 2. developmental spinal stenosis (the upper and lower decompression must extend beyond one or two segments of the lesion). There are different academic views on whether to perform a one-stage anterior-posterior decompression or two-stage surgical decompression in patients with significant anterior and posterior cervical spinal cord compression, and I believe that staged surgery should be performed in cases such as poor general health, older age, and more serious concomitant diseases, and that safety should not be disregarded for the sake of fashion. In fact, most patients require only one posterior laminoplasty decompression when multiple segments of the spinal cord are severely compressed anteriorly and posteriorly at the same time.
(3) Is internal fixation required? Internal fixation should be chosen if multiple subtotal vertebral body resections are performed anteriorly to prevent large implants from prolapsing, and in other cases, the patient’s affordability should be considered. Posterior decompression surgery generally does not require internal fixation if there is no significant instability.
(4) Higher safety and relatively simple procedures (upper cervical segment and cervicothoracic segment) should be considered. In case of anterior compression of the spinal cord in the upper cervical segment (C1-C3) (especially combined with multisegmental cervical OPLL), considering the difficulty of decompression and fixation via the anterior approach, high risk and easy complications, posterior decompression may be considered first (most patients have better results). If the posterior decompression is not effective, the second stage of anterior decompression and fixation through the oral or/and lateral anterior approach to the upper cervical spine can be considered (in fact, such patients rarely agree to undergo secondary surgery). In most cases of anterior spinal cord compression at the cervicothoracic junction (C7-T1), the sternum does not need to be split open to reveal, decompress and fix the spinal cord;
(5) To analyze the number of segments and the width of compression, so as to decide the scope and width of decompression;
(6) To analyze and determine which of the lesions of multiple segments in front of the spinal cord is the cause of the symptoms or the main cause, so as to decide the site of decompression or simple bone graft fusion;
(7) Minimally invasive techniques should be chosen as much as possible if the conditions and technology permit;
(8) Consideration should be given to affordability to decide whether to choose the implant and at what price level;
(9) Choose the skilled and mature procedure as much as possible according to their technical advantages. To sum up, for individual patients, the type of onset, age, occupation, lesion site, scope, the main compressed segment among multiple compressed segments, where the anterior and posterior compression is dominant, health tolerance, the hospital setting and objective conditions, and the doctor’s own technical mastery should be taken into consideration when choosing a specific surgical method, and then the most appropriate surgical procedure should be selected. Do not ignore other factors in the pursuit of newness.