Case information
Cui xx, female, 55 years old, was admitted to the hospital with progressive numbness and weakness of the extremities for half a month; the patient had a past history of heart disease for five years, hypertension for two years, nephritis for one month, and hyperglycemia for half a month. On admission: blood pressure 160/100mmHg, pulse 62 beats/min, clear, clear speech, muscle strength grade 4 in the left upper limb and both lower limbs, mild paralysis in the right upper limb, normal muscle tone in all four limbs, symmetrical presence of tendon reflexes in all four limbs, positive Babinski’s sign in both lower limbs, positive Hoffmann’s sign on the left side, positive Rossolimo’s sign bilaterally, hyperalgesia below the level of chest 7 on gross measurement, hyperalgesia in both lower limbs The pain sensation was decreased below the level of chest 7 on gross measurement, the vibration sensation was decreased in both lower limbs and bilateral wrist and shoulder joints, and the abdominal wall reflexes were decreased bilaterally.
Preoperative imaging data
3D CT of cervical spine
MRI of cervical spine
The patient’s condition worsened progressively and he could not walk on his own. The patient was referred to our department after consultation. On examination at the time of transfer to our department: bilateral hyperalgesia below the level of the fourth cervical level, with the right side being more severe. The muscle strength of the right limb was grade 4, the left limb was grade 3, and the fine function of the left hand was lost. The finger-nose test and alternating test were bilaterally clumsy, with the left side being the most important. Bilateral proprioceptive hypoesthesia. The ventral wall reflex, knee tendon reflex and Achilles tendon reflex were absent bilaterally. Babinski’s sign was positive in the lower extremities bilaterally. The patient’s condition and his family’s financial situation were taken into account and a single-opening posterior enlargement of the spinal canal was performed.
Traditional single-opening vertebroplasty in orthopedics
Diagram of Prof. Fengzeng Kan’s surgery
Diagram of Prof. Li Lixian’s surgical approach
Improvements.
1.The traditional single-opening surgery in orthopedics was changed from suture fixation to strong titanium plate and titanium nail fixation. Compared with the surgical method of Prof. Fengzeng Sugan, the titanium nail fixation of the spinous process was changed to two, which minimized the possibility of closing the door.
2. Cutting off the spinous process has facilitated the repositioning of the neck muscles and eliminated the postoperative neck discomfort of the patient.
Frontal and lateral cervical spine film
Oblique cervical spine film
3D CT sagittal reconstruction shows a significant widening of the anterior and posterior diameter of the spinal canal
3D CT axial reconstruction showed that the anterior and posterior diameters of the spinal canal were nearly doubled after single-opening vertebroplasty
The postoperative spinal canal was significantly widened and the spinal cord was no longer compressed
Post-operative condition: The patient’s condition improved significantly after surgery, with free movement of all four limbs, muscle strength grade 5, free walking, and flexible movement of both hands. Somatic sensation returned to normal.
Discussion
I. Selection of surgical modality for multisegmental cervical spondylosis
Pathologic-anatomical factors are the main determinants in determining the surgical route. These factors include
1. Sagittal alignment of the cervical spine
The patient’s normal or straightened cervical spine arc is essential for the implementation of vertebroplasty. If there is cervical retroflexion, anterior surgery should be preferred; if there is severe cervical retroflexion, combined anterior and posterior circumferential surgery may be more effective. If the flexion deformity is good, strong internal fixation with bone graft fusion by posterior approach can also be achieved.
2.The segments involved in the lesion
A. For lesions involving only 1-2 discs, anterior surgery should be performed, and for lesions involving 3 segments, anterior surgery should be carefully selected.
B. For patients requiring long segment decompression, posterior surgery is preferable if other conditions are compatible with the indications for posterior decompression. For patients who need to perform subtotal resection of 3 or 4 segments with bone graft fusion, it is better to choose the combined anterior and posterior surgery.
3.The presence of static subluxation on X-ray plain film
If there is dynamic subluxation on the flexion-extension film, it indicates cervical instability, and laminectomy alone cannot be performed, and the unstable segment must be fused and fixed.
4. Imaging manifestations of spinal cord compression
A. Patients with developmental spinal stenosis and exhibiting extensive stenosis from C3 to C7 typically show a small anterior-posterior diameter of the spinal cord and circumferential stenosis, which is better treated with laminoplasty.
B. The spinal cord is deformed by localized compression caused by discs or bony stenosis in front of the spinal cord, and the best results can be obtained by decompression through the anterior approach.
5. Bone quality of the patient
Patients with severe osteoporosis are quite risky to perform anterior cervical bone grafting alone, and posterior or combined anterior and posterior surgery can be considered to achieve the treatment purpose.
Advantages and disadvantages of anterior and posterior surgery
Advantages of anterior surgery:
1. For patients with anterior compression caused by lesions of anterior structures, such as disc herniation, posterior median or hooked vertebral joint redundancy and ossification of the posterior longitudinal ligament, anterior surgery can directly remove the anterior compression of the spinal cord and remove the main pathogenic factors. The rate of recovery or improvement of neurological function with anterior decompression and fusion is 80% to 90%. Anterior decompression not only decompresses the central spinal canal, but also removes the bony flab of the hook vertebral joint and treats neurogenic symptoms.
2.Another advantage of anterior cervical subtotal resection decompression implantation is that effective spinal fusion can be performed, which can be used to treat cervical instability and prevent delayed kyphosis, and can also correct preoperative kyphotic deformity.
3. Another potential benefit of subtotal vertebral body resection fusion is postoperative pain relief. Studies have shown that pain can be effectively relieved after decompression and fusion, especially in patients with spinal cervical spondylosis. Patients with long segmental or continuous posterior longitudinal ligament ossification often have stiffness in the neck and almost automatic fusion without the same painful planes as in degenerative disease.
Disadvantages of anterior vertebral fusion
1. The disadvantage of anterior subtotal vertebral body resection with osteotomy is the high technical requirements of the surgical operation, especially in patients with multi-segment subtotal vertebral body resection and ossification of the posterior longitudinal ligament. Although the abnormal bone and disc tissue compressing the spinal cord can be removed from the surface of the dural sac by the floating method and contactless technique, care should be taken to avoid rough operation and compression of the already compressed spinal cord, especially in patients with severe compression of the spinal cord in the form of fascicles. Severe ossification of the posterior longitudinal ligament may be accompanied by ossification of the dural sac leading to cerebrospinal fluid leakage.
2. Complications related to bone grafting are more common. Osteotomy requires careful preparation of the bone graft area and the bone graft block itself so that complications can be reduced, but displacement of the bone graft block and non-healing of the bone graft remain potential problems. The most common cases are fractures of the lower vertebral body and forward displacement of the implant, which often require revision surgery. The skeletal quality of the vertebral body is critical in reducing complications. Patients who have undergone multi-segmental laminectomy have a higher chance of displacement of the implant block, and although anterior plate fixation alone can be performed, a combined anterior-posterior approach with circumferential fusion is preferable.
3. Other disadvantages of anterior fusion include the need for postoperative airway monitoring, the need for bracing, and limited motion. With improvements in internal fixation instrumentation, the requirement for external fixation has gradually decreased, but strict braking is still required for patients with long-segment implants. Intervertebral fusion provides stability to the spine, but there is also a risk of degeneration of adjacent segments. It is not entirely clear which of these risks is more severe than the natural degenerative process of the disc itself, but theoretically there is an increased stress on the segment above and below the strong fused segment.
Posterior surgery
1. Advantages of posterior surgery.
A. One of the main advantages of posterior surgery is the relatively low technical difficulty. Compared with multi-segment anterior subtotal vertebral body resection with bone grafting, posterior laminoplasty, laminectomy, and even laminectomy with fusion are often easier and faster to perform, especially in obese patients with short, thick necks. In patients with ossification of the posterior longitudinal ligament, posterior surgery may also reduce the incidence of cerebrospinal fluid leakage.
B. Posterior surgery is less restrictive for multisegmental lesions, and the greatest advantage of this procedure may be to avoid the complications associated with anterior decompression with bone graft blocks.
2. Disadvantages of posterior surgery
A. The greatest risk of multisegmental laminectomy is the occurrence of posterior cervical lordosis after surgery. Inone et al. found that 10% of patients with spinal cervical spondylolisthesis who underwent posterior laminectomy had progressive cervical kyphosis after an 8-year follow-up. The incidence of kyphosis reported by Baba et al. was as high as 35%, but the patients did not develop neurological symptoms.
Most spinal cord compression is anterior, and posterior surgery can only provide indirect decompression of the spinal canal. Therefore, the spinal cord must be able to drift posteriorly in order to achieve relief of compression and allow neurological recovery. Preoperative cervical kyphosis, even after laminoplasty or laminectomy, can allow for persistent spinal cord compression. Because the spinal cord is stretched and stuck behind the discs, bones and vertebral bodies, posterior laminectomy and posterior extension fusion can allow the spinal cord to drift backward and achieve a better treatment outcome if the deformity is mobile. In patients with preoperative cervical instability or subluxation, posterior laminectomy or laminoplasty decompression alone will cause increased instability, and laminectomy decompression with bone graft fusion is then the best option. Although the incidence of spinal cord injury due to posterior surgery for spinal stenosis is relatively low, the incidence of C5 nerve root palsy after laminoplasty is higher than that of anterior decompression.
The advantages and disadvantages of anterior and posterior cervical spine surgery are summarized below
Advantages and disadvantages
Anterior surgery 1. direct decompression 1. high technical requirements
2. fusion stability 2. bone graft complications
3. correction of deformity 3. postoperative external fixation brake required
4. axial lengthening of the spine 4. partial loss of range of motion
5. good axial pain relief 5. degeneration of adjacent segments
Posterior surgery 1. less loss of range of motion 1. non-direct decompression
2. Less technical requirements 2. Anterior convex deformity and/or instability limited by surgery
3. low external fixation requirements 3. poor recovery from axial pain
4. avoid bone graft complications 4. delayed instability
Combined anterior-posterior surgery
Combined anterior-posterior surgery can compensate for the deficiencies of anterior and posterior surgery applied separately, while retaining their respective advantages. Multi-segment anterior subtotal vertebral body resection decompression and implant fusion coupled with posterior fusion allows direct decompression of the spinal canal, correction of deformity, treatment of axial pain, and reduction of implant block complications by posterior internal fixation and implant fusion. The procedure also reduces the requirement for postoperative external fixation support and also greatly reduces the incidence of pseudoarthrosis. However, older patients often have difficulty tolerating this major surgery.
Summary
There are no randomized controlled trials comparing the efficacy of anterior or posterior surgery for spinal or radicular cervical spondylosis, but there are some reports of experience with anterior and posterior surgery.Herkowit compared anterior vertebral fusion, posterior laminectomy, and laminoplasty and found that the excellent rates of anterior decompressive implant fusion were similar to those of posterior laminoplasty (92% and The excellent rate of anterior decompression-implant fusion was similar to that of posterior laminoplasty (92% and 86%, respectively), while the excellent rate of laminectomy-decompression was lower (66%), with 25% of the patients developing kyphosis in the cervical spine within 2 years after surgery. During follow-up, Edwards et al. found that patients undergoing anterior fusion required more analgesic treatment than patients undergoing laminoplasty; patients undergoing anterior surgery had a higher rate of intraoperative complications than patients undergoing posterior surgery; and patients undergoing anterior surgery had a higher rate of intraoperative complications than patients undergoing posterior surgery. Patients undergoing anterior surgery had a greater rate of intraoperative complications than patients undergoing posterior surgery; and the sagittal range of motion of the cervical spine was reduced by 57% in patients undergoing anterior surgery and 38% in patients undergoing laminoplasty. The authors advocate the use of laminoplasty for the treatment of multisegmental spinal cervical spondylosis to prevent cervical kyphosis. They reported 91 patients treated with laminectomy, anterior interbody fusion, and subtotal vertebral body resection concluded that subtotal vertebral body resection was relatively effective and recommended for patients with three or fewer intervertebral space lesions, while extended laminectomy decompression was recommended for patients with four or more intervertebral space lesions.
The currently accepted indications are as follows.
1, The best indications for anterior subtotal laminectomy with bone graft fusion are patients with limited compression anterior to the spinal cord requiring single or double laminectomy; those with straightened cervical curvature or posterior convexity deformity; those with preoperative cervical subluxation; and those with severe preoperative axial pain.
2. The best indications for vertebroplasty are patients with multisegmental extensive cervical spinal stenosis with normal cervical physiological curvature and no cervical instability; patients with ossification of the posterior longitudinal ligament of the cervical spine; and patients with mild preoperative neck pain. If the patient has a flexion deformity and the normal position can be maintained by extension fixation and bone grafting, it is necessary to supplement with bone grafting fusion, or to perform additional anterior surgery under the condition of ensuring the safety of anterior surgery.
3. The indications for combined anterior and posterior surgery are patients with osteoporosis requiring anterior multisegmental decompression; patients after laminectomy; patients with partial subtotal resection of three vertebrae and patients with subtotal resection of all four vertebrae; patients with moderate to severe posterior convexity deformity preoperatively and those with postoperative braking difficulties due to obesity or restricted mobility.