• Users Online: 133
  • Print this page
  • Email this page


 
 Table of Contents  
SYMPOSIUM - CERVICAL SPONDYLOMYELOPATHY
Year : 2019  |  Volume : 2  |  Issue : 1  |  Page : 42-51

Posterior surgical options for spondylotic cervical myelopathy


Department of Orthospine, Sir Ganga Ram Hospital, New Delhi, India

Date of Web Publication11-Jan-2019

Correspondence Address:
Dr. Shankar Acharya
Department of Spine Surgery, Room No: 1218 A, Sir Ganga Ram Hospital, New Delhi
India
Login to access the Email id

Source of Support: None, Conflict of Interest: None


DOI: 10.4103/isj.isj_57_18

Get Permissions

  Abstract 


Cervical spondylotic myelopathy (CSM) is a common presentation in the middle-aged to elderly population. The cause of myelopathy is multifactorial, and cervical spondylosis is the most common cause. This review looks into the treatment options, timing of the surgery, and the advantages and disadvantages of the various posterior approaches for multilevel spondylotic myelopathy. CSM is a disabling disorder that should be addressed in its early phases. There are limited surgical options available, and each procedure has its advantages and disadvantages. Since the neurological and functional outcomes are the same for all well-performed decompressions, the choice of surgical approach depends on various other factors. Posterior approaches are good for multilevel disease as they make the surgery simpler, shorter and with reduced complications in comparison to multilevel anterior surgeries.

Keywords: Cervical, management, myelopathy, posterior, surgery


How to cite this article:
Acharya S, Jain N. Posterior surgical options for spondylotic cervical myelopathy. Indian Spine J 2019;2:42-51

How to cite this URL:
Acharya S, Jain N. Posterior surgical options for spondylotic cervical myelopathy. Indian Spine J [serial online] 2019 [cited 2019 Jan 15];2:42-51. Available from: http://www.isjonline.com/text.asp?2019/2/1/42/249900




  Introduction Top


Cervical spondylotic myelopathy (CSM) is a fairly common presentation in the middle-aged to the elderly population. With the life expectancy in the Indian population increasing in the past two decades, more and more people are presenting with symptoms of myelopathy. Furthermore, Indians are at a higher risk of diabetes due to lifestyle and genetic predisposition. In such a scenario, it becomes important to be able to understand the nuances of the disease with its presentation because it is not uncommon to have diabetes and concomitant myelopathy. These patients present with numbness and tingling in the limbs, clumsiness of hands, difficulty walking, and instability of gait along with frequents falls. At this age hearing difficulty, visual impairment, osteoarthritis of hip and knee joints may add to the cause of instabilities and gait disturbances, sometimes masking or mimicking the symptoms of myelopathy. Hence, in our country, recognizing the problem and selecting the correct patient for surgery is of utmost importance.

The cause of myelopathy is multifactorial and cervical spondylosis is the most common cause. Aging discs with concomitant facet osteoarthropathy, ligamentum flavum hypertrophy and buckling, lead to focal stenosis and cord compression.[1] Chronic cervical cord compression and subsequent cord ischemia lead to neural tract degeneration and causes myelopathy.[2] Ossification of the posterior longitudinal ligament (OPLL) in genetically predisposed patients and fluorosis in endemic areas also leads to compressive myelopathy.

Noncompressive myelopathy due to nutritional deficiency (Vitamin B12), inflammatory, toxic, vascular, hereditary, postradiation, paraneoplastic syndromes, and motor neuron diseases must be ruled out because such patients will not benefit from surgery. On the contrary surgery in these patients could make the condition worse.[3]


  History and Physical Examination Top


A detailed history of a patient of cervical myelopathy should be taken, and problems such as bad knees, poor vision, hearing loss, cerebrovascular accident, diabetes, or brain disorders should be ruled out. A combination of multiple comorbidities can be a diagnostic challenge. Patients with lumbar spinal stenosis present with heaviness, numbness, and paresthesia in the lower limbs and difficulty in walking after a certain distance. Such patients should be cautiously examined for any symptoms of upper limb or neck pain, as cervical stenosis coexists in 30% of the cases.[3],[4],[5]

A detailed physical examination should include examination of all the large and small joints to rule out osteoarthritis and inflammatory arthritis. Peripheral neuropathies and peripheral vascular diseases should be ruled out. Clinical findings in myelopathy patients include a variety of signs, and they should be properly assessed.[5],[6],[7],[8]

All the clinical findings should be radiologically and electrophysiologically confirmed. Investigations include X-ray, magnetic resonance imaging (MRI), computed tomography (CT) scan and peripheral Doppler studies. These tests are crucial in patients with multiple comorbidities such as diabetes, neuropathy, arthritis, and stroke.[9],[10],[11],[12]

Electrophysiological testing is helpful in very early cases where the signs and symptoms are minimal and confusing, and the MRI findings are also not clear. These tests include motor and somatosensory evoked potentials, electromyography, and nerve conduction studies. They help differentiating between cervical cord, nerve root, brachial plexus, and more peripheral lesions.[13]


  Patient Selection Top


The patient selection for surgery from this diverse group of patients is of the utmost importance, necessitating a systemic approach. Once sure that the history, clinical examination, electrophysiological tests, and radiological findings correlate with the clinical picture, it is important to know when to intervene. Not all patients require surgery and not all surgically treated patients benefit from it. Nurick grading and modified Japanese Orthopedic Association Score (mJOA) are the two clinical scales that classify these patients as per the symptoms and are followed worldwide.[14],[15]

In the Nurick system, high grade means increased disability, and in mJOA a low score means increased disability. The mJOA is divided into three types: mild, moderate, and severe and they are as follows: mild: 17–12; moderate: 12–9; and severe: <9.[16]

Clinical scales only judge the patient as per their present condition. Since myelopathy is a chronic disorder, how the patients have behaved in the recent past is also important. About 70% of the patients have a slow, steady deterioration with intervening periods of stability/minimal progression, 20% of the patients deteriorate steadily with no stable intervals, and 5% deteriorate rapidly in a very short time. So along with the present clinical score, the progression of the disease is also very important for selecting the right treatment option for the patient.[17],[18]


  Ideal Patients For Surgery Top


Undergoing surgery is a major step and has its inherent risk and morbidity. Ideal patients for the surgery would be the ones who are likely to get significant benefit from it. The patients who have Nurick grades <2 or mJOA scores >12 are minimally disabled and do not have significant MRI changes. For such patients, the risk and morbidity of the surgery might be more than the disorder morbidity itself. Such patients may be put under observation and conservative management. The patients with Nurick grade >3 and a mJOA score <9 are in the advanced stage of the disease, the cord is severely atrophied, MRI shows cystic changes, neural tissue has ischemic changes, and the chances of recovery are slim. Such patients should be cautiously managed as they might deteriorate from surgical insult. The ideal patients for surgery are the ones with moderate and progressive symptoms, with minimal changes of the cord in the MRI. A mJOA score of ≤12 and Nurick Grade 2 and 3 are good indicators for surgery. The success of surgery depends on the duration of onset of symptoms, and generally better results are obtained when operated within 6 months of onset of symptoms [Table 1].[19],[20],[21],[22],[23],[24]
Table 1: Ideal patient for surgery

Click here to view


Patients with mild or moderate mJOA scores but nonprogressive disability can be managed with observation and supportive treatment. However, these patients have a very high risk of spinal cord injury leading to hospitalization and disability if there is a sudden forceful movement of the neck like in a whiplash injury. Hence, conservatively managed patients should be explained all the precautions in detail.[25],[26],[27],[28]

Hirabayashi et al., as per their experience and observation of 53 patients operated for OPLL over 16 years, gave a formula to help us assess the expected rate of recovery for the patients using mJOA scores.[29],[30]

Postoperative score − preoperative score

17 maximum score − p

This formula can be used to calculate the expected recovery rate of these patients as per their mJOA scores. Low mJOA scores have poor recovery rates, and high mJOA scores indicate better recovery rates. 17 is the score of a normal individual and is the maximum score on mJOA.

The statistically significant factors that affect the outcome of a surgery are a follows:[10],[31],[32]

  1. Preoperative transverse area of the spinal cord at the level of maximum compression (<30 mm2 had unsatisfactory surgical results. The cord is not able to survive below 30 mm2 transverse area)
  2. Chronicity of the myelopathy symptoms (longer the duration, poorer the surgical outcome)
  3. High signal changes on T2-weighted imaging sequences of the spinal cord before surgery (multisegmental areas of high intensity have a poor prognosis, indicating more severe pathologic changes in the spinal cord)
  4. Low-signal intensity changes in the spinal cord in T1 weighted imaging sequences indicate poor prognosis
  5. The multiplicity of the involvement (single level involvement has the best postoperative outcome)
  6. Age at the time of surgery (with increasing age, surgical results worsen).



  Choice of Approach and Type of Surgery Top


Once the decision to operate on a patient with CSM is taken, then the question remains as to which approach and what method should be used. The optimal surgical approach is not yet clear, and the debate still goes on. The main factors are:

  1. Cervical curvature – lordotic, neutral or kyphotic spine
  2. C2–C7 Sagittal Vertical Axis (SVA)
  3. K-line
  4. Number of levels involved 1, 2, 3, or more
  5. Location of compression: anterior or posterior
  6. The pattern of compression soft to hard disc, OPLL (continuous vs. intermittent)
  7. Surgeon preference and other facilities
  8. Patients risk factor such as diabetes mellitus, smoking, and any other illness.


If well performed, the neurologic recovery and functional outcomes have been found similar in both anterior and posterior approaches. The posterior approaches rely on the ability of the cord to “drift away” from the anterior pathology. Here, the role of cervical curvature becomes very important. Significant kyphosis prevents the cord from drifting back and away from the pathology. Earlier C2–C7 Cobbs' angle was used to measure cervical lordosis. Now, we use the C2–C7 sagittal vertical axis to assess the cervical sagittal alignment. It is calculated as anterior deviation of C2 plumb line from posterior superior endplate of C7 [Figure 1].
Figure 1: C2–C7 Sagittal Vertical Axis calculated as anterior deviation of C2 plumb line from posterior superior corner of C7

Click here to view


Posterior approaches remove the posterior tension band of the cervical spine. Kyphosis will progress if a noninstrumented nonfusion posterior surgery is performed in an already kyphotic cervical spine. The cord is not able to drift away in such a scenario, and decompression fails. More than 40 mm SVA deviation is associated with poor outcome with posterior nonfusion approaches.[33]

The K-line helps assess the extent of the encroachment of the cervical canal by the anterior pathology. It is measured on lateral neutral radiographs of the cervical spine where a line is drawn from the center of the canal at C2 to center of the canal at C7 vertebra. K-Line can also be reproduced on the mid-sagittal sections of the MRI cervical spine films. The anterior pathologies extending beyond the K line are termed K (−) and the pathologies falling short of the K line are termed K (+). The K (−) pathologies are unsuitable for posterior-only approach [Figure 2]a and [Figure 2]b.[34],[35]
Figure 2: (a and b) Diagram showing cervical cord alignment (black solid line) over a kyphotic versus a lordotic cervical vertebrae

Click here to view


Anterior surgical approach

This approach directly removes the pathology compressing the cervical cord from the anterior and is useful in lordotic, straight, and kyphotic cervical spine.[36] The details with the advantages and disadvantages of the anterior approach have been discussed in another article.

Posterior surgical approach

The earliest surgeries of the cervical spine employed the posterior approach because posterior elements are superficial and easy to palpate.[37] Laminectomy is the oldest of all procedures in this approach. Around the time of World War II, the posterior surgeries fell into disfavor, but now, they have become the procedures of choice in multilevel spondylotic myelopathy. The posterior approach does not remove the pathology present anteriorly, but it allows the spinal cord to be able to float/drift away from the anterior discogenic or retrovertebral compression. This is possible only in neutral or lordotic cervical curvatures, as a kyphotic spine will stay draped with the cord due to its weight and alignment, even if the posterior elements have been removed completely.[38],[39] Posterior approaches involve removal of posterior muscles and midline bony structures, making the spine unstable. Such procedures are useful only where anterior procedures are not feasible. In cases where the pathology extends to 3 or more levels, it is prudent to decompress posteriorly because the risk of complications from an anterior approach might outweigh the benefits. Because the posterior approach makes cervical spine unstable, postoperative neck pain and postoperative kyphosis are common complications. One noteworthy point is that the C5 nerve root is short, thin and hence prone to traction injury. When the cord is decompressed, and it drifts away, the C5 nerve root gets pulled, leading to deltoid and biceps weakness along with numbness along the outer aspect of the arm.[40]

Laminectomy, laminectomy with instrumented fusion and laminoplasty

Laminectomy was the original procedure described for posterior surgeries. The first successful laminectomy was performed by Alban G Smith in 1828 who performed a 3 level laminectomy in a paraplegic patient and the patient improved. The first laminectomy to remove a herniated disc was performed by Scaglietti in 1949. French window laminectomy was introduced by Kirita et al. in 1975. In this, the lamina was thinned using an air drill and then the lamina and flavum was cut from the midline. The two flaps created to look like a French window would then be excised. The present surgical technique involves using a high-speed burr drill. The supraspinous and interspinous ligaments above and below the level of laminectomy are cut. Then using the burr at the lamina-lateral mass junction on both sides, the outer cortex and the cancellous bone is drilled away, and the inner cortical bone is thinned. The thinned out lamina and the underlying ligamentum flavum is cut using a Kerrisons rongeur and using a Kocher's forceps the whole of the posterior element is lifted off the dorsal surface of the cord. During the surgery it is important to be gentle and not to put any instrument blindly under the lamina else it may compress the cord and cause a neural deficit. Decompression up to the lateral border of the dural sac is considered as sufficient. Undercutting of the C2 and C7 can be done to prevent kinking of the cord. Laminectomy of the C2 and C7 laminas is not advisable as it makes the head unstable and the neck rapidly progresses to kyphosis. It is imperative not to remove more than 25% of the facet joints. 50% or more of facets, if resected lead to instability and posterior instrumentation will be necessary.[41] Although laminectomy provides good posterior decompression, many complications have been noted. Laminectomy increases the flexibility and makes the cervical spine unstable at the lower ends, leading to kyphosis.[42] A kyphotic, hypermobile, and unstable spine causes neck pain and spinal cord trauma. After laminectomy cases have been reported where a membrane gets formed over the dura, called as the “postlaminectomy membrane” which can lead to restenosis and late neurological symptoms.[43],[44],[45] It is also important to preserve the muscle attachment to C2 and C7 to preserve the cervical lordosis. Laminectomy alone is contraindicated for kyphotic cervical spines, especially if the kyphosis is >13° [Figure 3]a,[Figure 3]b,[Figure 3]c.[39]
Figure 3: (a-c) Preoperative X-ray cervical spine lateral view, magnetic resonance imaging cervical spine sagittal section and computed tomography cervical spine sagittal section showing maintained cervical lordosis, degenerative cervical spondylosis, multilevel cervical stenosis and cord oedema. C3–C6 laminectomy was performed

Click here to view


Postlaminectomy instability and preoperative deficient posterior elements in the cervical spine were the reason why posterior instrumentation and fusion with laminectomy were introduced. In 1989 Roy Camille introduced the lateral mass plates and screws which were further refined by Magerl et al.[46] Abumi et al. in 1994 introduced subaxial cervical spine pedicle screws instrumentation following the idea of 3 column fixation by pedicle screws in thoracic and lumbar spine.[47] Modern equipment includes cervical lateral mass, pedicle, and translaminar screws along with local or iliac crest bone graft for fusion after central laminectomy. With instrumented fusion, the incidence of postoperative neck pain and kyphosis was minimized. However, there was the problem of decreased postoperative range of motion in the neck, graft site pain, nonunion at fusion site, implant failure, increased costs of surgery, adjacent segment disease and infection. The risk of C5 nerve root palsy remained the same.[48] It is important that while operating on a postlaminectomy kyphotic cervical spine, correction of more than 9° at each segment can lead to excessive translation of cord posteriorly, and this can lead to neurological deterioration sooner or later.[49] Vertebral artery injuries can happen during the cervical spine surgery at any time, and it is very important to know how to handle it. It is a life-threatening situation for the patient and a frightening emergency for the surgeon. The surgeon needs to control the hemorrhage, prevent central neural ischemia, and prevent air embolism. The best option is to have a competent vascular surgeon available and let him handle the situation. If the injury is due to the screw perforating the vertebral artery, do not remove the screw as it provides the tamponade effect and prevents frank hemorrhage. If the injury has happened at another site, the site of bleeding should be digitally pressed on and packed with Gelfoam and cottonoids. Then expose the vertebral artery in the foramen transversarium one level above and one level below the injury site and clip both the ends with aneurysm clips. Injury site can then be repaired. In case the vessel is irreparable, and the contralateral vertebral artery is patent, the decision to ligate the injured vertebral artery or bypass the artery can be taken which should be done by a competent vascular surgeon. It is important to keep the neck neutral during the whole procedure to prevent kinking of the contralateral vertebral artery and prevent any embolism [Figure 4]a, [Figure 4]b and [Figure 5].[50]
Figure 4: (a and b) Preoperative X-ray and magnetic resonance imaging sagittal sections, of degenerative cervical spondylotic myelopathy with multilevel cervical stenosis

Click here to view
Figure 5: Postoperative X-ray cervical spine, lateral view, following C3–C6 central laminectomy and posterior instrumented fusion with C3–C6 lateral mass screws

Click here to view


While the world was focusing on instrumentation, the Japanese were working on motion preserving posterior surgery called “Laminoplasty.” In 1981, Hukuda et al. introduced French window laminoplasty by suturing the two flaps created by Kirita, to the paraspinal muscles.[51] Oyama and Hattori from Japan modified this technique by cutting the thinned lamina into a Z shape and then lifting them and fixing them with sutures; “Z laminoplasty” [Figure 6].
Figure 6: “Z-laminoplasty” technique

Click here to view


Tsuji would cut the lamina bilaterally at the lamina and lateral mass junction and let them float freely over the cord [Figure 7].[52]
Figure 7: Tsuji technique

Click here to view


Hirabayashi et al. used the Tsuji technique and developed the expansive “open door” laminoplasty, and this is a popular technique. The author also uses this technique.[53] At present, we have three types of commonly used laminoplasty; open door technique, French door/double door technique, and the T-saw technique. “Open door” technique involves cutting the lamina-lateral mass junction on one side and opening the posterior elements, like a single door hinged over the contralateral lamina-lateral mass junction. “French door/double door” technique involves splitting the spinous process from the midline and holding both the laminas wide apart.[54] “T-saw” technique is the same as the French door technique but uses a T-saw instead of a high-speed burr.[55] Fixation is done using metal plates and bone grafts [Figure 8]a and [Figure 8]b.
Figure 8: Open door (a) versus French door (b) technique

Click here to view


Laminoplasty preserves the lamina, and the risk of postlaminectomy membrane formation over dura is minimal. Although the posterior elements are preserved in laminoplasty, the patients still have been found to develop axial neck pain and deformity after the surgery.[56] To prevent this, muscles from C2 and C7 spinous process should not be detached. If injured, they should be repaired properly.[57],[58]

Furthermore, “muscle sparing laminoplasty” techniques can be used. First technique involves subperiosteal dissection of the muscles of the spinous process on one side, then cutting the spinous process at the base, separating it from the lamina and then retracting the spinous process away, with the contralateral muscles still attached to it.[59] The Shiraishi technique involves severing the interspinalis attachments and preserving the semispinalis.[60] Kim performs myoarchitectonic spinolaminoplasty where he splits the spinous process in the midline, cuts the spinous processes from the base and retracts them with their muscles attached to their respective sides, away from the midline, to expose the lamina [Figure 9].[61]
Figure 9: Kim's myoarchitectonic spinolaminoplasty technique

Click here to view


Laminoplasty is indicated for patients with a stable spine, maintained cervical lordosis, minimal neck pain, local kyphosis <13° and in patients with OPLL not crossing the K line (K +) [Figure 10]a, [Figure 10]b and [Figure 11]a,[Figure 11]b,[Figure 11]c,[Figure 11]d, [Table 2] and [Table 3].[34]
Figure 10: (a and b) Preoperative magnetic resonance imaging sagittal and axial images of stenotic cervical canal with cord compression and cord oedema

Click here to view
Figure 11: (a-d) Postoperative X-ray cervical spine lateral view, sagittal magnetic resonance imaging, sagittal computed tomography scan and axial computed tomography scan cervical spine postlaminoplasty, with miniplates in situ, showing widened cervical canal area and cervical cord floating away from the anterior pathology

Click here to view
Table 2: Comparison of laminectomy, laminectomy with lateral mass fusion and laminoplasty

Click here to view
Table 3: Complications and corrective measures/precautions

Click here to view



  Clinical Outcomes Following Posterior Surgery in Cervical Spondylotic Myelopathy Top


Laminoplasty versus laminectomy with instrumented fusion

The patients with well-performed cervical laminectomy, cervical laminoplasty, and laminectomy with instrumented fusion have a similar functional and neurological recovery. Comparing the other complications of each procedure, the operative time and blood loss is more in the patients who undergo laminectomy and instrumented fusion. The incidence of dysphagia and wound infection is also higher in the instrumented fusion group. The possible reasons are increased duration of surgery, more extensive dissection and muscle trauma and more hardware implanted compared to the laminoplasty group. Although the incidence of these complications is higher in the instrumentation group, it is not statistically significantly different from the laminoplasty group. The risk of C5 palsy also stays the same in both techniques.[44],[48],[64] The muscle preserving techniques in laminoplasty have demonstrated a significant decrease in postoperative neck pain, shoulder pain, adjacent segment degeneration and instability compared to older laminoplasty techniques, and laminectomy with instrumented fusion. These techniques claim to preserve the muscle attachments, cervical extensor musculature, and cervical curvature compared to the older laminoplasty techniques. The old laminoplasty techniques focused more on lamina but missed out on musculature reconstruction. Laminectomy with instrumented fusion involves stripping off all the posterior cervical musculature and wide dissection that makes cervical spine prone to postoperative neck pain and instability.[61] But still more studies are required to establish these results.

Anterior versus posterior approach

The neurological and functional outcomes are similar for a well-performed surgery through an anterior or posterior approach. If we compare the complication rates, the posterior approaches have a higher incidence of infection and blood loss, even though the operative time remains similar in both the approaches. The factors can be more extensive muscle dissection, more hardware implanted, rich blood supply of the face and anterior neck, and a very important fact that posterior approaches are being employed mainly for multilevel (3 or more) disease. The incidence of dysphagia and C5 nerve palsy remains the same in both the approaches [Table 4].[48]
Table 4: Treatment algorithm in cervical spondylotic myelopathy

Click here to view



  Conclusion Top


CSM is a disabling disorder that should be addressed in its early phases. Any suspicious finding should be thoroughly evaluated. The treatment depends on the stage of the disease, progression of the disease and the MRI changes in the cervical cord. The choice of surgical approach depends on various other factors, as the neurological and functional outcomes are the same for both anterior and posterior approaches. At our center, we perform both laminoplasty and laminectomy with fusion in cases of multiple level spondylotic myelopathy in the indicated patients. We have found the functional and neurological results to be satisfactory with minimal complications and none of the cases needing revision surgery. Posterior approaches are good for multilevel disease as they make the surgery simpler and shorter compared to multilevel anterior surgeries. This also decreases the risk of complication rates postoperatively and aids in a faster rehabilitation of the patient. The patients should also be given total rehabilitative care, and they should be followed up closely to watch for late complications.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
  References Top

1.
Cusick JF. Pathophysiology and treatment of cervical spondylotic myelopathy. Clin Neurosurg 1991;37:661-81.  Back to cited text no. 1
    
2.
Bohlman HH, Emery SE. The pathophysiology of cervical spondylosis and myelopathy. Spine (Phila Pa 1976) 1988;13:843-6.  Back to cited text no. 2
    
3.
Salvi FJ, Jones JC, Weigert BJ. The assessment of cervical myelopathy. Spine J 2006;6:182S-9S.  Back to cited text no. 3
    
4.
de Oliveira Vilaça C, Orsini M, Leite MA, de Freitas MR, Davidovich E, Fiorelli R, et al. Cervical spondylotic myelopathy: What the neurologist should know. Neurol Int 2016;8:6330.  Back to cited text no. 4
    
5.
Wang L, Hee HT, Wong HK. (IV) Cervical spondylotic myelopathy: A brief review of its pathophysiology, presentation, assessment, natural history and management. Orthop Trauma 2011;25:181-9.  Back to cited text no. 5
    
6.
Lavelle WF, Bell GR. Cervical myelopathy: History and physical examination. Semin Spine Surg 2007;19:6-11.  Back to cited text no. 6
    
7.
Heller JG. The syndromes of degenerative cervical disease. Orthop Clin North Am 1992;23:381-94.  Back to cited text no. 7
    
8.
Karadimas SK, Gatzounis G, Fehlings MG. Pathobiology of cervical spondylotic myelopathy. Eur Spine J 2015;24 Suppl 2:132-8.  Back to cited text no. 8
    
9.
Emery SE. Cervical spondylotic myelopathy: Diagnosis and treatment. J Am Acad Orthop Surg 2001;9:376-88.  Back to cited text no. 9
    
10.
Wada E, Yonenobu K, Suzuki S, Kanazawa A, Ochi T. Can intramedullary signal change on magnetic resonance imaging predict surgical outcome in cervical spondylotic myelopathy? Spine (Phila Pa 1976) 1999;24:455-61.  Back to cited text no. 10
    
11.
Epstein N. Ossification of the cervical posterior longitudinal ligament: A review. Neurosurg Focus 2002;13:ECP1.  Back to cited text no. 11
    
12.
Guan X, Fan G, Wu X, Gu G, Gu X, Zhang H, et al. Diffusion tensor imaging studies of cervical spondylotic myelopathy: A systemic review and meta-analysis. PLoS One 2015;10:e0117707.  Back to cited text no. 12
    
13.
Khan MR, McInnes A, Hughes SP. Electrophysiological studies in cervical spondylosis. J Spinal Disord 1989;2:163-9.  Back to cited text no. 13
    
14.
Benzel EC, Lancon J, Kesterson L, Hadden T. Cervical laminectomy and dentate ligament section for cervical spondylotic myelopathy. J Spinal Disord 1991;4:286-95.  Back to cited text no. 14
    
15.
Nurick S. The pathogenesis of the spinal cord disorder associated with cervical spondylosis. Brain 1972;95:87-100.  Back to cited text no. 15
    
16.
Revanappa KK, Rajshekhar V. Comparison of nurick grading system and modified Japanese orthopaedic association scoring system in evaluation of patients with cervical spondylotic myelopathy. Eur Spine J 2011;20:1545-51.  Back to cited text no. 16
    
17.
St. Clair S, Bell GR. Natural history of cervical spondylotic myelopathy. Semin Spine Surg 2007;19:2-5.  Back to cited text no. 17
    
18.
Clarke E, Robinson PK. Cervical myelopathy: A complication of cervical spondylosis. Brain 1956;79:483-510.  Back to cited text no. 18
    
19.
Ghogawala Z, Whitmore RG. Asymptomatic cervical canal stenosis: Is there a risk of spinal cord injury? Spine J 2013;13:613-4.  Back to cited text no. 19
    
20.
Bednarik J, Kadanka Z, Dusek L, Kerkovsky M, Vohanka S, Novotny O, et al. Presymptomatic spondylotic cervical myelopathy: An updated predictive model. Eur Spine J 2008;17:421-31.  Back to cited text no. 20
    
21.
Kadanka Z, Mares M, Bednaník J, Smrcka V, Krbec M, Stejskal L, et al. Approaches to spondylotic cervical myelopathy: Conservative versus surgical results in a 3-year follow-up study. Spine (Phila Pa 1976) 2002;27:2205-10.  Back to cited text no. 21
    
22.
Sampath P, Bendebba M, Davis JD, Ducker TB. Outcome of patients treated for cervical myelopathy. A prospective, multicenter study with independent clinical review. Spine (Phila Pa 1976) 2000;25:670-6.  Back to cited text no. 22
    
23.
Yoshimatsu H, Nagata K, Goto H, Sonoda K, Ando N, Imoto H, et al. Conservative treatment for cervical spondylotic myelopathy. Prediction of treatment effects by multivariate analysis. Spine J 2001;1:269-73.  Back to cited text no. 23
    
24.
Rhee JM, Shamji MF, Erwin WM, Bransford RJ, Yoon ST, Smith JS, et al. Nonoperative management of cervical myelopathy: A systematic review. Spine (Phila Pa 1976) 2013;38:S55-67.  Back to cited text no. 24
    
25.
Chen LF, Tu TH, Chen YC, Wu JC, Chang PY, Liu L, et al. Risk of spinal cord injury in patients with cervical spondylotic myelopathy and ossification of posterior longitudinal ligament: A national cohort study. Neurosurg Focus 2016;40:E4.  Back to cited text no. 25
    
26.
Wu JC, Chen YC, Liu L, Huang WC, Chen TJ, Lo SS, et al. Conservatively treated ossification of the posterior longitudinal ligament increases the risk of spinal cord injury: A nationwide cohort study. J Neurotrauma 2012;29:462-8.  Back to cited text no. 26
    
27.
Tetreault LA, Karadimas S, Wilson JR, Arnold PM, Kurpad S, Dettori JR, et al. The natural history of degenerative cervical myelopathy and the rate of hospitalization following spinal cord injury: An updated systematic review. Global Spine J 2017;7:28S-34S.  Back to cited text no. 27
    
28.
Wu JC, Ko CC, Yen YS, Huang WC, Chen YC, Liu L, et al. Epidemiology of cervical spondylotic myelopathy and its risk of causing spinal cord injury: A national cohort study. Neurosurg Focus 2013;35:E10.  Back to cited text no. 28
    
29.
Hirabayashi K, Miyakawa J, Satomi K, Maruyama T, Wakano K. Operative results and postoperative progression of ossification among patients with ossification of cervical posterior longitudinal ligament. Spine (Phila Pa 1976) 1981;6:354-64.  Back to cited text no. 29
    
30.
Fujiwara K, Yonenobu K, Ebara S, Yamashita K, Ono K. The prognosis of surgery for cervical compression myelopathy. An analysis of the factors involved. J Bone Joint Surg Br 1989;71:393-8.  Back to cited text no. 30
    
31.
Okada Y, Ikata T, Yamada H, Sakamoto R, Katoh S. Magnetic resonance imaging study on the results of surgery for cervical compression myelopathy. Spine (Phila Pa 1976) 1993;18:2024-9.  Back to cited text no. 31
    
32.
Bakhsheshian J, Mehta VA, Liu JC. Current diagnosis and management of cervical spondylotic myelopathy. Global Spine J 2017;7:572-86.  Back to cited text no. 32
    
33.
Roguski M, Benzel EC, Curran JN, Magge SN, Bisson EF, Krishnaney AA, et al. Postoperative cervical sagittal imbalance negatively affects outcomes after surgery for cervical spondylotic myelopathy. Spine (Phila Pa 1976) 2014;39:2070-7.  Back to cited text no. 33
    
34.
Fujiyoshi T, Yamazaki M, Kawabe J, Endo T, Furuya T, Koda M, et al. Anew concept for making decisions regarding the surgical approach for cervical ossification of the posterior longitudinal ligament: The K-line. Spine (Phila Pa 1976) 2008;33:E990-3.  Back to cited text no. 34
    
35.
Koda M, Mochizuki M, Konishi H, Aiba A, Kadota R, Inada T, et al. Comparison of clinical outcomes between laminoplasty, posterior decompression with instrumented fusion, and anterior decompression with fusion for K-line (-) cervical ossification of the posterior longitudinal ligament. Eur Spine J 2016;25:2294-301.  Back to cited text no. 35
    
36.
Daniels AH, Riew KD, Yoo JU, Ching A, Birchard KR, Kranenburg AJ, et al. Adverse events associated with anterior cervical spine surgery. J Am Acad Orthop Surg 2008;16:729-38.  Back to cited text no. 36
    
37.
Denaro V, Di Martino A. Cervical spine surgery: An historical perspective. Clin Orthop Relat Res 2011;469:639-48.  Back to cited text no. 37
    
38.
Sodeyama T, Goto S, Mochizuki M, Takahashi J, Moriya H. Effect of decompression enlargement laminoplasty for posterior shifting of the spinal cord. Spine (Phila Pa 1976) 1999;24:1527-31.  Back to cited text no. 38
    
39.
Suda K, Abumi K, Ito M, Shono Y, Kaneda K, Fujiya M, et al. Local kyphosis reduces surgical outcomes of expansive open-door laminoplasty for cervical spondylotic myelopathy. Spine (Phila Pa 1976) 2003;28:1258-62.  Back to cited text no. 39
    
40.
Yalamanchili PK, Vives MJ, Chaudhary SB. Cervical spondylotic myelopathy: Factors in choosing the surgical approach. Adv Orthop 2012;2012:783762.  Back to cited text no. 40
    
41.
Laminectomy in the Cervical Spine: Indications, Surgical Tec. : Contemporary Spine Surgery. Available from: https://www.journals.lww.com/cssnewsletter/Abstract/2000/11000/Laminectomy_in_the_Cervical_Spine__Indications.,1.aspx. [Last accessed on 2018 Nov 25].  Back to cited text no. 41
    
42.
Ryken TC, Heary RF, Matz PG, Anderson PA, Groff MW, Holly LT, et al. Cervical laminectomy for the treatment of cervical degenerative myelopathy. J Neurosurg Spine 2009;11:142-9.  Back to cited text no. 42
    
43.
Kitahara T, Hanakita J, Takahashi T. Postlaminectomy membrane with dynamic spinal cord compression disclosed with computed tomographic myelography: A case report and literature review. Spinal Cord Ser Cases 2017;3:17056.  Back to cited text no. 43
    
44.
Ratliff JK, Cooper PR. Cervical laminoplasty: A critical review. J Neurosurg 2003;98:230-8.  Back to cited text no. 44
    
45.
Morimoto T, Okuno S, Nakase H, Kawaguchi S, Sakaki T. Cervical myelopathy due to dynamic compression by the laminectomy membrane: Dynamic MR imaging study. J Spinal Disord 1999;12:172-3.  Back to cited text no. 45
    
46.
Roy-Camille R, Saillant G, Mazel C. Internal fixation of the unstable cervical spine by a posterior osteosynthesis with plates and screws. In: Cervical Spine Research Society. The cervical Spine. 2nd ed. Philadelphia: JB Lippicott; 1989. p. 390-403.  Back to cited text no. 46
    
47.
Abumi K, Itoh H, Taneichi H, Kaneda K. Transpedicular screw fixation for traumatic lesions of the middle and lower cervical spine: Description of the techniques and preliminary report. J Spinal Disord 1994;7:19-28.  Back to cited text no. 47
    
48.
Fehlings MG, Smith JS, Kopjar B, Arnold PM, Yoon ST, Vaccaro AR, et al. Perioperative and delayed complications associated with the surgical treatment of cervical spondylotic myelopathy based on 302 patients from the AOSpine north America cervical spondylotic myelopathy study. J Neurosurg Spine 2012;16:425-32.  Back to cited text no. 48
    
49.
Hojo Y, Ito M, Abumi K, Kotani Y, Sudo H, Takahata M, et al. Alate neurological complication following posterior correction surgery of severe cervical kyphosis. Eur Spine J 2011;20:890-8.  Back to cited text no. 49
    
50.
Schroeder GD, Hsu WK. Vertebral artery injuries in cervical spine surgery. Surg Neurol Int 2013;4:S362-7.  Back to cited text no. 50
[PUBMED]  [Full text]  
51.
Hukuda S, Mochizuki T, Ogata M, Shichikawa K, Shimomura Y. Operations for cervical spondylotic myelopathy. A comparison of the results of anterior and posterior procedures. J Bone Joint Surg Br 1985;67:609-15.  Back to cited text no. 51
    
52.
Tsuji H. Laminoplasty for patients with compressive myelopathy due to so-called spinal canal stenosis in cervical and thoracic regions. Spine (Phila Pa 1976) 1982;7:28-34.  Back to cited text no. 52
    
53.
Hirabayashi K, Watanabe K, Wakano K, Suzuki N, Satomi K, Ishii Y, et al. Expansive open-door laminoplasty for cervical spinal stenotic myelopathy. Spine (Phila Pa 1976) 1983;8:693-9.  Back to cited text no. 53
    
54.
Hoshi K, Kurokawa T, Nakamura K, Hoshino Y, Saita K, Miyoshi K, et al. Expansive cervical laminoplasties – Observations on comparative changes in spinous process lengths following longitudinal laminal divisions using autogenous bone or hydroxyapatite spacers. Spinal Cord 1996;34:725-8.  Back to cited text no. 54
    
55.
Kiely PD, Quinn JC, Du JY, Lebl DR. Posterior surgical treatment of cervical spondylotic myelopathy: Review article. HSS J 2015;11:36-42.  Back to cited text no. 55
    
56.
Hosono N, Yonenobu K, Ono K. Neck and shoulder pain after laminoplasty. A noticeable complication. Spine (Phila Pa 1976) 1996;21:1969-73.  Back to cited text no. 56
    
57.
Takeuchi T, Shono Y. Importance of preserving the C7 spinous process and attached nuchal ligament in French-door laminoplasty to reduce postoperative axial symptoms. Eur Spine J 2007;16:1417-22.  Back to cited text no. 57
    
58.
Iizuka H, Shimizu T, Tateno K, Toda N, Edakuni H, Shimada H, et al. Extensor musculature of the cervical spine after laminoplasty: Morphologic evaluation by coronal view of the magnetic resonance image. Spine (Phila Pa 1976) 2001;26:2220-6.  Back to cited text no. 58
    
59.
Okada M, Minamide A, Endo T, Yoshida M, Kawakami M, Ando M, et al. Aprospective randomized study of clinical outcomes in patients with cervical compressive myelopathy treated with open-door or French-door laminoplasty. Spine (Phila Pa 1976) 2009;34:1119-26.  Back to cited text no. 59
    
60.
Shiraishi T. A new technique for exposure of the cervical spine laminae. Technical note. J Neurosurg 2002;96:122-6.  Back to cited text no. 60
    
61.
Kim P, Murata H, Kurokawa R, Takaishi Y, Asakuno K, Kawamoto T, et al. Myoarchitectonic spinolaminoplasty: Efficacy in reconstituting the cervical musculature and preserving biomechanical function. J Neurosurg Spine 2007;7:293-304.  Back to cited text no. 61
    
62.
Satomi K, Ogawa J, Ishii Y, Hirabayashi K. Short-term complications and long-term results of expansive open-door laminoplasty for cervical stenotic myelopathy. Spine J 2001;1:26-30.  Back to cited text no. 62
    
63.
Mochida J, Nomura T, Chiba M, Nishimura K, Toh E. Modified expansive open-door laminoplasty in cervical myelopathy. J Spinal Disord 1999;12:386-91.  Back to cited text no. 63
    
64.
Matsunaga S, Sakou T, Nakanisi K. Analysis of the cervical spine alignment following laminoplasty and laminectomy. Spinal Cord 1999;37:20-4.  Back to cited text no. 64
    


    Figures

  [Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6], [Figure 7], [Figure 8], [Figure 9], [Figure 10], [Figure 11]
 
 
    Tables

  [Table 1], [Table 2], [Table 3], [Table 4]



 

Top
 
 
  Search
 
Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
Access Statistics
Email Alert *
Add to My List *
* Registration required (free)

 
  In this article
Abstract
Introduction
History and Phys...
Patient Selection
Ideal Patients F...
Choice of Approa...
Clinical Outcome...
Conclusion
References
Article Figures
Article Tables

 Article Access Statistics
    Viewed48    
    Printed0    
    Emailed0    
    PDF Downloaded12    
    Comments [Add]    

Recommend this journal


[TAG2]
[TAG3]
[TAG4]