Role of magnetic resonance imaging in predicting surgical outcome in patients with cervical spondylotic myelopathy

Magnetic Resonance Imaging-CCCFLS Scoring System: Toward Predicting Clinical Symptoms and C5 Paralysis

STUDY DESIGN

A retrospective study.

OBJECTIVE

To develop a new MRI scoring system to assess patients' clinical characteristics, outcomes and complications.

METHODS

A retrospective 1-year follow-up study of 366 patients with cervical spondylosis from 2017 to 2021. The CCCFLS scores (cervical curvature and balance (CC), spinal cord curvature (SC), spinal cord compression ratio (CR), cerebrospinal fluid space (CFS). Spinal cord and lesion location (SL). Increased Signal Intensity (ISI) were divided into Mild group (0-6), Moderate group (6-12), and Severe group (12-18) for comparison, and the Japanese Orthopaedic Association (JOA) scores, visual analog scale (VAS), numerical rating scale (NRS), Neck Disability Index (NDI) and Nurick scores were evaluated. Correlation and regression analyses were performed between each variable and the total model in relation to clinical symptoms and C5 palsy.

RESULTS

The CCCFLS scoring system was linearly correlated with JOA, NRS, Nurick and NDI scores, with significant differences in JOA scores among patients with different CC, CR, CFS, ISI scores, with a predictive model (R2 = 69.3%), and significant differences in preoperative and final follow-up clinical scores among the 3 groups, with a higher rate of improvement in JOA in the severe group (P < .05), while patients with and without C5 paralysis had significant differences in preoperative SC and SL (P < .05).

CONCLUSION

CCCFLS scoring system can be divided into mild (0-6). moderate (6-12), severe (12-18) groups. It can effectively reflect the severity of clinical symptoms, and the improvement rate of JOA is better in the severe group, while the preoperative SC and SL scores are closely related to C5 palsy.

LEVEL OF EVIDENCE

III.

Identifying and exploring the favorable factors that help to slow the progression of disease in patients with mild cervical spondylotic myelopathy

To explore the favorable factors that help slow the progression of disease in patients with mild Cervical Spondylotic Myelopathy (CSM). A retrospective analysis was conducted, involving the enrollment of 115 CSM patients. The categorization of patients into two groups was based on the duration of symptoms, assessments using the mJOA scale and Health Transition (HT) scores: mild-slow group and severe-rapid group. We found that the patients in both groups had similar degrees of spinal cord compression, but mild-slow group were older and had smaller C2-C7 cobb angle (Flexion) (CL(F)), C2-C7 cobb angle (Range of motion) (CL(ROM)), Transverse area (TA), Normal-TA, Compressive spinal canal area (CSCA), Normal-Spinal canal area (Normal-SCA) and lower Spinal cord increased signal intensity (ISI) Grade than the severe-rapid group. A binary logistic regression analysis showed that CL(ROM) and Normal-TA are favorable factors to help slow the progression of disease patients with mild CSM. Through ROC curves, we found that when CL(ROM) < 39.1° and Normal-TA < 80.5mm2, the progression of disease in CSM patients may be slower. Meanwhile, we obtained a prediction formula by introducing joint prediction factor: L = CL(ROM) + 2.175 * Normal-TA. And found that when L < 213.0, the disease progression of patients may be slower which was superior to calculate CL(ROM) and Normal-TA separately.

Contemporary Practice Patterns in the Treatment of Cervical Stenosis and Central Cord Syndrome: A Survey of the Cervical Spine Research Society

STUDY DESIGN

Cross-sectional study.

OBJECTIVE

To evaluate for areas of consensus and divergence of opinion within the spine community regarding the management of cervical spondylotic conditions and acute traumatic central cord syndrome (ATCCS) and the influence of the patient's age, disease severity, and myelomalacia.

SUMMARY OF BACKGROUND DATA

There is ongoing disagreement regarding the indications for, and urgency of, operative intervention in patients with mild degenerative myelopathy, moderate to severe radiculopathy, isolated axial symptomatology with evidence of spinal cord compression, and ATCCS without myelomalacia.

METHODS

A survey request was sent to 330 attendees of the Cervical Spine Research Society (CSRS) 2021 Annual Meeting to assess practice patterns regarding the treatment of cervical stenosis, myelopathy, radiculopathy, and ATCCS in 16 unique clinical vignettes with associated MRIs. Operative versus nonoperative treatment consensus was defined by a management option selected by >80% of survey participants.

RESULTS

Overall, 116 meeting attendees completed the survey. Consensus supported nonoperative management for elderly patients with axial neck pain and adults with axial neck pain without myelomalacia. Operative management was indicated for adult patients with mild myelopathy and myelomalacia, adult patients with severe radiculopathy, elderly patients with severe radiculopathy and myelomalacia, and elderly ATCCS patients with pre-existing myelopathic symptoms. Treatment discrepancy in favor of nonoperative management was found for adult patients with isolated axial symptomatology and myelomalacia. Treatment discrepancy favored operative management for elderly patients with mild myelopathy, adult patients with mild myelopathy without myelomalacia, elderly patients with severe radiculopathy without myelomalacia, and elderly ATCCS patients without preceding symptoms.

CONCLUSIONS

Although there is uncertainty regarding the treatment of mild myelopathy, operative intervention was favored for nonelderly patients with evidence of myelomalacia or radiculopathy and for elderly patients with ATCCS, especially if pre-injury myelopathic symptoms were present.

LEVEL OF EVIDENCE

Level V.

Potential thresholds of critically increased cardiac-related spinal cord motion in degenerative cervical myelopathy

Introduction

New diagnostic techniques are a substantial research focus in degenerative cervical myelopathy (DCM). This cross-sectional study determined the significance of cardiac-related spinal cord motion and the extent of spinal stenosis as indicators of mechanical strain on the cord.

Methods

Eighty-four DCM patients underwent MRI/clinical assessments and were classified as MRI+ [T2-weighted (T2w) hyperintense lesion in MRI] or MRI- (no T2w-hyperintense lesion). Cord motion (displacement assessed by phase-contrast MRI) and spinal stenosis [adapted spinal canal occupation ratio (aSCOR)] were related to neurological (sensory/motor) and neurophysiological readouts [contact heat evoked potentials (CHEPs)] by receiver operating characteristic (ROC) analysis.

Results

MRI+ patients (N = 31; 36.9%) were more impaired compared to MRI- patients (N = 53; 63.1%) based on the modified Japanese Orthopedic Association (mJOA) subscores for upper {MRI+ [median (Interquartile range)]: 4 (4-5); MRI-: 5 (5-5); p < 0.01} and lower extremity [MRI+: 6 (6-7); MRI-: 7 (6-7); p = 0.03] motor dysfunction and the monofilament score [MRI+: 21 (18-23); MRI-: 24 (22-24); p < 0.01]. Both patient groups showed similar extent of cord motion and stenosis. Only in the MRI- group displacement identified patients with pathologic assessments [trunk/lower extremity pin prick score (T/LEPP): AUC = 0.67, p = 0.03; CHEPs: AUC = 0.73, p = 0.01]. Cord motion thresholds: T/LEPP: 1.67 mm (sensitivity 84.6%, specificity 52.5%); CHEPs: 1.96 mm (sensitivity 83.3%, specificity 65.6%). The aSCOR failed to show any relation to the clinical assessments.

Discussion

These findings affirm cord motion measurements as a promising additional biomarker to improve the clinical workup and to enable timely surgical treatment particularly in MRI- DCM patients.

Clinical trial registration

www.clinicaltrials.gov, NCT02170155.

Associating T1-Weighted and T2-Weighted Magnetic Resonance Imaging Radiomic Signatures With Preoperative Symptom Severity in Patients With Cervical Spondylotic Myelopathy

BACKGROUND

Preoperative symptom severity in cervical spondylotic myelopathy (CSM) can be variable. Radiomic signatures could provide an imaging biomarker for symptom severity in CSM. This study utilizes radiomic signatures of T1-weighted and T2-weighted magnetic resonance imaging images to correlate with preoperative symptom severity based on modified Japanese Orthopaedic Association (mJOA) scores for patients with CSM.

METHODS

Sixty-two patients with CSM were identified. Preoperative T1-weighted and T2-weighted magnetic resonance imaging images for each patient were segmented from C2-C7. A total of 205 texture features were extracted from each volume of interest. After feature normalization, each second-order feature was further subdivided to yield a total of 400 features from each volume of interest for analysis. Supervised machine learning was used to build radiomic models.

RESULTS

The patient cohort had a median mJOA preoperative score of 13; of which, 30 patients had a score of >13 (low severity) and 32 patients had a score of ≤13 (high severity). Radiomic analysis of T2-weighted imaging resulted in 4 radiomic signatures that correlated with preoperative mJOA with a sensitivity, specificity, and accuracy of 78%, 89%, and 83%, respectively (P < 0.004). The area under the curve value for the ROC curves were 0.69, 0.70, and 0.77 for models generated by independent T1 texture features, T1 and T2 texture features in combination, and independent T2 texture features, respectively.

CONCLUSIONS

Radiomic models correlate with preoperative mJOA scores using T2 texture features in patients with CSM. This may serve as a surrogate, objective imaging biomarker to measure the preoperative functional status of patients.

Time course of symptomatic improvement after open-door laminoplasty for cervical spondylotic myelopathy

BACKGROUND

Postoperative outcomes following cervical spondylotic myelopathy (CSM) are excellent overall, but there are few prospective studies using patient-reported outcome measures that have explored how long improvement can be expected after surgery. The aim of this prospective study was to investigate from when and until when symptoms improve after open-door laminoplasty in patients with CSM and the factors that affect surgical outcomes.

METHODS

The subjects were 115 CSM patients who underwent laminoplasty. The Japanese Orthopaedic Association Cervical Myelopathy Evaluation Questionnaire (JOACMEQ) was used for longitudinal evaluation, and surveys on cervical spine function, upper extremity function, lower extremity function, bladder function, and quality of life were conducted before surgery and at 3, 6, 12, 18, and 24 months after surgery. The patients were classified into 'effective' and 'ineffective' groups based on the points obtained for each domain, and the factors affecting the outcome of surgery were examined by multivariate analysis.

RESULTS

JOACMEQ scores improved significantly at 3 months postoperatively compared to preoperatively for all four domains except cervical spine function, but there was no significant improvement after 3 months postoperatively. Multivariate analysis showed that the preoperative score (cervical spine function and upper extremity function) and the points obtained at 3 months postoperatively (upper and lower extremity function, bladder function, and quality of life) were the factors associated with membership of the effective group at 24 months postoperatively.

CONCLUSIONS

Although upper and lower extremity function, bladder function, and quality of life domains improved in the relatively early postoperative period, improvement after 3 months postoperatively was limited. The results suggest that the preoperative score and the superiority of the improvement obtained up to 3 months after surgery may be indicators of postoperative outcomes, and this may provide new insights into the selection of surgical indications and patient explanations.

Investigation of perfusion impairment in degenerative cervical myelopathy beyond the site of cord compression

The aim of this study was to determine tissue-specific blood perfusion impairment of the cervical cord above the compression site in patients with degenerative cervical myelopathy (DCM) using intravoxel incoherent motion (IVIM) imaging. A quantitative MRI protocol, including structural and IVIM imaging, was conducted in healthy controls and patients. In patients, T2-weighted scans were acquired to quantify intramedullary signal changes, the maximal canal compromise, and the maximal cord compression. T2*-weighted MRI and IVIM were applied in all participants in the cervical cord (covering C1-C3 levels) to determine white matter (WM) and grey matter (GM) cross-sectional areas (as a marker of atrophy), and tissue-specific perfusion indices, respectively. IVIM imaging resulted in microvascular volume fraction ([Formula: see text]), blood velocity ([Formula: see text]), and blood flow ([Formula: see text]) indices. DCM patients additionally underwent a standard neurological clinical assessment. Regression analysis assessed associations between perfusion parameters, clinical outcome measures, and remote spinal cord atrophy. Twenty-nine DCM patients and 30 healthy controls were enrolled in the study. At the level of stenosis, 11 patients showed focal radiological evidence of cervical myelopathy. Above the stenosis level, cord atrophy was observed in the WM (- 9.3%; p = 0.005) and GM (- 6.3%; p = 0.008) in patients compared to healthy controls. Blood velocity (BV) and blood flow (BF) indices were decreased in the ventral horns of the GM (BV: - 20.1%, p = 0.0009; BF: - 28.2%, p = 0.0008), in the ventral funiculi (BV: - 18.2%, p = 0.01; BF: - 21.5%, p = 0.04) and lateral funiculi (BV: - 8.5%, p = 0.03; BF: - 16.5%, p = 0.03) of the WM, across C1-C3 levels. A decrease in microvascular volume fraction was associated with GM atrophy (R = 0.46, p = 0.02). This study demonstrates tissue-specific cervical perfusion impairment rostral to the compression site in DCM patients. IVIM indices are sensitive to remote perfusion changes in the cervical cord in DCM and may serve as neuroimaging biomarkers of hemodynamic impairment in future studies. The association between perfusion impairment and cervical cord atrophy indicates that changes in hemodynamics caused by compression may contribute to the neurodegenerative processes in DCM.

Automated signal intensity analysis of the spinal cord for detection of degenerative cervical myelopathy - a matched-pair MRI study

PURPOSE

Detection of T2 hyperintensities in suspected degenerative cervical myelopathy (DCM) is done subjectively in clinical practice. To gain objective quantification for dedicated treatment, signal intensity analysis of the spinal cord is purposeful. We investigated fully automated quantification of the T2 signal intensity (T2-SI) of the spinal cord using a high-resolution MRI segmentation.

METHODS

Matched-pair analysis of prospective acquired cervical 3D T2-weighted sequences of 114 symptomatic patients and 88 healthy volunteers. Cervical spinal cord was segmented automatically through a trained convolutional neuronal network with subsequent T2-SI registration slice-by-slice. Received T2-SI curves were subdivided for each cervical level from C2 to C7. Additionally, all levels were subjectively classified concerning a present T2 hyperintensity. For T2-positive levels, corresponding T2-SI curves were compared to curves of age-matched volunteers at the identical level.

RESULTS

Forty-nine patients showed subjective T2 hyperintensities at any level. The corresponding T2-SI curves showed higher signal variabilities reflected by standard deviation (18.51 vs. 7.47 a.u.; p < 0.001) and range (56.09 vs. 24.34 a.u.; p < 0.001) compared to matched controls. Percentage of the range from the mean absolute T2-SI per cervical level, introduced as "T2 myelopathy index" (T2-MI), was correspondingly significantly higher in T2-positive segments (23.99% vs. 10.85%; p < 0.001). ROC analysis indicated excellent differentiation for all three parameters (AUC 0.865-0.920).

CONCLUSION

This fully automated T2-SI quantification of the spinal cord revealed significantly increased signal variability for DCM patients compared to healthy volunteers. This innovative procedure and the applied parameters showed sufficient diagnostic accuracy, potentially diagnosing radiological DCM more objective to optimize treatment recommendation.

TRIAL REGISTRATION

DRKS00012962 (17.01.2018) and DRKS00017351 (28.05.2019).

Cervical muscle morphometry and composition demonstrate prognostic value in degenerative cervical myelopathy outcomes

Objectives

This study aimed to examine whether preoperative cervical muscle size, composition, and asymmetry from magnetic resonance imaging (MRI) can predict post-operative outcomes in patients with degenerative cervical myelopathy (DCM).

Methods

A total of 171 patients with DCM were included. Relative total cross-sectional area (RCSA), functional CSA (fat-free area, FCSA), ratio of FCSA/CSA (fatty infiltration) and asymmetry of the multifidus (MF) and semispinalis cervicis (SCer) together (MF + SCer), and cervical muscle as a group (MF, SCer, semispinalis capitis, and splenius capitis) were obtained from T2-weighted axial MR images at the mid-disk, at the level of maximum cord compression and the level below. Univariate and multivariate linear regression analyses were used to assess the relationship between baseline cervical muscle measurements of interest with the modified Japanese Orthopedic Association (mJOA), Nurick Classification, Neck Disability Index (NDI), and SF-36 health survey at 6-month and 12-month post-surgery.

Results

Lower RCSA of MF + SCer, less CSA MF + SCer asymmetry and greater FCSA/CSA for the cervical muscle group (e.g., less fatty infiltration), and younger age were significant predictors of higher mJOA scores (e.g., less disability) at 6-month and 12-month post-surgery (all p < 0.05). Greater CSA asymmetry in MF + SCer and lower FCSA/CSA (e.g., more fatty infiltration) for the cervical muscle group were significant predictors of higher Nurick scores (e.g., more disability) at 6-month and 12-month post-surgery (all p < 0.05). Lower FCSA MF + Scer asymmetry, lower FCSA/CSA asymmetry of the muscle group, and greater RCSA MF + SCer were significant predictors of higher NDI scores at 6-month and 12-month post-surgery. Finally, greater FCSA/CSA asymmetry of the MF + SCer, greater FCSA asymmetry of the muscle group, greater RCSA of the muscle group, and greater CSA asymmetry of MF + SCer were significant predictors of lower post-operative SF-36 scores at 6- and 12-month post-surgery.

Conclusion

Our result suggested that cervical paraspinal muscle morphology, specifically greater asymmetry, and fatty infiltration may be important predictors of functional recovery and post-surgical outcomes in patients with DCM.

Utility of MRI in Quantifying Tissue Injury in Cervical Spondylotic Myelopathy

Cervical spondylotic myelopathy (CSM) is a progressive disease that worsens over time if untreated. However, the rate of progression can vary among individuals and may be influenced by various factors, such as the age of the patients, underlying conditions, and the severity and location of the spinal cord compression. Early diagnosis and prompt treatment can help slow the progression of CSM and improve symptoms. There has been an increased use of magnetic resonance imaging (MRI) methods in diagnosing and managing CSM. MRI methods provide detailed images and quantitative structural and functional data of the cervical spinal cord and brain, allowing for an accurate evaluation of the extent and location of tissue injury. This review aims to provide an understanding of the use of MRI methods in interrogating functional and structural changes in the central nervous system in CSM. Further, we identified several challenges hindering the clinical utility of these neuroimaging methods.

Degenerative cervical myelopathy: Where have we been? Where are we now? Where are we going?

Degenerative cervical myelopathy (DCM), a recently coined term, encompasses a group of age-related and genetically associated pathologies that affect the cervical spine, including cervical spondylotic myelopathy and ossification of the posterior longitudinal ligament (OPLL). Given the significant contribution of DCM to global disease and disability, there are worldwide efforts to promote research and innovation in this area. An AO Spine effort termed 'RECODE-DCM' was initiated to create an international multistakeholder consensus group, involving patients, caregivers, physicians and researchers, to focus on launching actionable discourse on DCM. In order to improve the management, treatment and results for DCM, the RECODE-DCM consensus group recently identified ten priority areas for translational research. The current article summarizes recent advancements in the field of DCM. We first discuss the comprehensive definition recently refined by the RECODE-DCM group, including steps taken to arrive at this definition and the supporting rationale. We then provide an overview of the recent advancements in our understanding of the pathophysiology of DCM and modalities to clinically assess and diagnose DCM. A focus will be set on advanced imaging techniques that may offer the opportunity to improve characterization and diagnosis of DCM. A summary of treatment modalities, including surgical and nonoperative options, is then provided along with future neuroprotective and neuroregenerative strategies. This review concludes with final remarks pertaining to the genetics involved in DCM and the opportunity to leverage this knowledge toward a personalized medicine approach.

Predictors of poor clinical outcome in patients with cervical spondylotic myelopathy undergoing cervical laminectomy and fusion

BACKGROUND

Cervical spondylotic myelopathy (CSM) is a common degenerative disease that arises from spinal cord compression and injury. Laminectomy with posterior spinal fusion (LPSF) is one of the most common approaches used to treat patients with CSM. The present study aimed to evaluate predictors of poor clinical outcome in patients with CSM undergoing LPSF.

METHODS

We retrospectively evaluated 157 patients with CSM who underwent LPSF at our center between April 2014 and June 2019. The neurological outcome was assessed using the modified Japanese Orthopaedic Association (mJOA) scale before the surgery and at the last follow-up visit. Based on the clinical outcomes, all patients were divided into two groups [the good group (recovery rates ≥ 75%) and the poor group (recovery rates < 75%)]. The following suggested variables as potential predictors for the poor clinical outcome were compared between the two groups:age, gender, body mass index (BMI), smoking, diabetes, number of laminectomy levels, presence of signal changes in Magnetic Resonance Imaging (MRI), duration of symptoms, preoperative JOA scale, preoperative Pavlov ratio, preoperative cervical curvature, and preoperative cervical range of motion (ROM).

RESULTS

There were 86 males (54.8%) and 71 females (45.2%) with the mean follow-up time of 24.96 ± 1.67 months. Overall, 114 patients (72.6%) had a good clinical outcome. However, 43 subjects (27.4%) failed to achieve a good outcome. According to the binary logistic regression analysis, age (odds ratio [OR], 2.14; 95% confidence interval [95% CI], 1.87-2.63; P = 0.014) and preoperative JOA scale (OR, 3.73; 95% CI 2.96-4.87; p < 0.001) were independent predictors of poor clinical outcome.

CONCLUSIONS

The results of the present study showed that age and preoperative JOA scale were predictors of poor clinical outcome in patients with CSM undergoing LPSF. These findings will be of great value in preoperative counseling and management of postoperative expectations.

Simple and Reliable Magnetic Resonance Imaging Parameter to Predict Postoperative Ambulatory Function in Patients With Metastatic Epidural Spinal Cord Compression

STUDY DESIGN

Retrospective case-control study.

OBJECTIVES

The aim of this study was to develop a simple and reliable imaging parameter to predict postoperative ambulatory status in patients with metastatic epidural spinal cord compression (MESCC).

METHODS

Sixty-three patients with MESCC underwent spine surgery because of neurologic deficits were included. On preoperative axial MRI, the cord compression ratio was analyzed for postoperative ambulatory status. The relationship between other imaging features, such as fracture of the affected vertebra and increased T2 signal intensity of the spinal cord at the compression level, and the postoperative ambulatory status were also analyzed.

RESULTS

Cord compression ratio and increased T2 signal change of the spinal cord were significantly different between the postoperative ambulatory group and the non-ambulatory group. Receiver operating characteristic analysis showed that the optimal cut-off value was 0.84. In the multivariate regression analysis, only a cord compression ratio of more than 0.84 was significantly associated with postoperative ambulatory status (odds ratio = 10.80; 95% confidence interval = 2.79-41.86; P = .001). Interobserver/intraobserver agreements were strong for the cord compression ratio, however those agreements were weak for increased T2 signal intensity.

CONCLUSIONS

On preoperative MRI, the cord compression ratio may predict postoperative ambulatory status in patients with MESCC. The measurement of this imaging parameter was simple and reliable. This imaging predictor may be helpful for both clinicians and patients.

The Role of Magnetic Transcranial Stimulation in the Diagnosis and Post-Surgical Follow-Up of Cervical Spondylotic Myelopathy

Degenerative cervical myelopathy (DCM) consists of spinal cord damage due to its compression through the cervical spine. The leading cause is degenerative. The diagnosis is clinical, and the therapeutic approach is usually surgical. Confirmation of the diagnostic suspicion is done by magnetic resonance imaging (MRI); however, this test lacks functional information of the spinal cord, the abnormality of which may precede involvement in neuroimaging. Neurophysiological examination using somatosensory evoked potentials (SSEPs) and transcranial magnetic stimulation (TMS) allows for an evaluation of spinal cord function, and provides information in the diagnostic process. Its role in the post-surgical follow-up of patients undergoing decompressive surgery is being studied. We present a retrospective study of 24 patients with DCM and surgical decompression who underwent neurophysiological tests (TMS and SSEP) before, 6, and 12 months after surgery. The result of the TMS and the SSEP in the post-operative follow-up did not correlate with the clinical outcome, either subjective or measured by clinical scales at six months. We only found post-surgical improvement of central conduction times (CMCTs) in patients with severe pre-surgical motor impairment on TMS. In patients with normal pre-surgical CMCT, we found a transient worsening with return to baseline at the one-year follow-up. Most patients presented pre-surgical increased P40 latency at diagnosis. CMCT and SSEP were more related to clinical outcomes one year after the surgical procedure and were very useful in diagnosing.

Influence of clinical and radiological parameters on the likelihood of neurological improvement after surgery for degenerative cervical myelopathy

OBJECTIVE

Degenerative cervical myelopathy (DCM) is routinely treated with surgical decompression, but disparate postoperative outcomes are frequently observed, ranging from complete neurological recovery to persistent decline. Although numerous clinical and radiological factors have been independently associated with failure to improve, the relative impact of these proposed risk factors remains obscure. In this study, the authors assess the combined role of clinical and radiographic parameters in contributing to failure to attain neurological improvement after surgery.

METHODS

A consecutive series of patients who underwent surgery for DCM between July 2013 and August 2018 at a single institution was identified from a prospectively maintained database. Retrospective chart review was undertaken to record perioperative clinical and radiographic parameters. Failure to improve on the last follow-up evaluation after surgery, defined as a change in modified Japanese Orthopaedic Association (mJOA) score less than 2, was the primary outcome in univariate and multivariate analyses.

RESULTS

The authors included 183 patients in the final cohort. In total, 109 (59.6%) patients improved (i.e., responders with ΔmJOA score ≥ 2) after surgery and 74 (40.4%) were nonresponders with ΔmJOA score < 2. Baseline demographic variables and comorbidity rates were similar, whereas baseline Nurick score was the only clinical variable that differed between responders and nonresponders (2.7 vs 3.0, p = 0.02). In contrast, several preoperative radiographic variables differed between the groups, including presence and degree of cervical kyphosis, number of levels with bidirectional cord compression, presence and number of levels with T2-weighted signal change, intramedullary lesion (IML) length, Torg ratio, and both narrowest spinal canal and cord diameter. On multivariate analysis, preoperative degree of kyphosis at C2-7 (OR 1.19, p = 0.004), number of levels with bidirectional compression (OR 1.83, p = 0.003), and IML length (OR 1.14, p < 0.001) demonstrated the highest predictive power for nonresponse (area under the receiver operating characteristic curve 0.818). A risk factor point system that predicted failure of improvement was derived by incorporating these 3 variables.

CONCLUSIONS

When a large spectrum of both clinical and radiographic variables is considered, the degree of cervical kyphosis, number of levels with bidirectional compression, and IML length are the most predictive of nonresponse after surgery for DCM. Assessment of these radiographic factors can help guide surgical decision-making and more appropriately stratify patients in clinical trials.

New Imaging Modalities for Degenerative Cervical Myelopathy

INTRODUCTION

Degenerative cervical myelopathy (DCM) is defined as dysfunction of the spinal cord as a result of compression from degenerative changes to surrounding joints, intervertebral disks, or ligaments. Symptoms can include upper extremity numbness and diminished dexterity, difficulty with fine manipulation of objects, gait imbalance, and incoordination, and compromised bowel and bladder function. Accurate diagnosis and evaluation of the degree of impairment due to degenerative cervical myelopathy remain a challenging clinical endeavor requiring a thorough and accurate history, physical examination, and assessment of imaging findings.

METHODS

A narrative review is presented summarizing the current landscape of imaging modalities utilized in DCM diagnostics and the future direction of research for spinal cord imaging.

RESULTS AND DISCUSSION

Current imaging modalities, particularly magnetic resonance imaging and, to a lesser extent, radiographs/CT, offer important information to aid in decision making but are not ideal as stand-alone tools. Newer imaging modalities currently being studied in the literature include diffusion tensor imaging, MR spectroscopy, functional magnetic resonance imaging, perfusion imaging, and positron emission tomography. These newer imaging modalities attempt to more accurately evaluate the physical structure, intrinsic connectivity, biochemical and metabolic function, and perfusion of the spinal cord in DCM. Although there are still substantial limitations to implementation, future clinical practice will likely be revolutionized by these new imaging modalities to diagnose, localize, surgically plan and manage, and follow patients with DCM.

Are surgical outcomes for one level anterior decompression and fusion associated with MRI parameters for degenerative cervical myelopathy?

Background

Our study is to determine the correlation between preoperative MRI parameters of spinal cord compression and the effects of anterior surgery in patients with degenerative cervical myelopathy (DCM).

Methods

24 normal subjects with no evident abnormalities were selected as group A. 79 patients with DCM underwent single-segment (C4–5/C5–6) ACDF surgery formed the operation group, and separated into group B (without high signal) and group C (with high signal) according to the absence or presence of high signal in the spinal cord on preoperative T2-weighted MRI respectively. MRI parameters (MCC, maximum canal compromise; MSCC, maximum spinal cord compression; CR, spinal cord compression rate; RCSCDS, ratio of cervical spinal cord to dura sac) were measured. The JOA score was used to evaluate cervical spinal cord function and recovery rate (RR) was used to evaluate postoperative efficacy. The relationship between preoperative MRI parameters and postoperative efficacy was analyzed.

Results

The preoperative JOA score and RR of group B were higher than that of group C. MCC and MSCC in group B were significantly lower than those in groups C. The multiple linear regression equation was the fitted postoperative JOA score = 13.371–2.940 * MCC −5.660 * RCSCDS +0.471 * preoperative JOA score. The fitted RR = 1.451–0.472 * MCC −1.313 * RCSCDS.

Conclusion

The occurrence of high signal on T2-weighted images could reflect more serious spinal cord injury. The postoperative JOA score was significantly correlated with MCC, RCSCDS, and preoperative JOA score, while RR was significantly associated with MCC and RCSCDS.

Imaging and Electrophysiology for Degenerative Cervical Myelopathy [AO Spine RECODE-DCM Research Priority Number 9]

STUDY DESIGN

Narrative review.

OBJECTIVE

The current review aimed to describe the role of existing techniques and emerging methods of imaging and electrophysiology for the management of degenerative cervical myelopathy (DCM), a common and often progressive condition that causes spinal cord dysfunction and significant morbidity globally.

METHODS

A narrative review was conducted to summarize the existing literature and highlight future directions.

RESULTS

Anatomical magnetic resonance imaging (MRI) is well established in the literature as the key imaging tool to identify spinal cord compression, disc herniation/bulging, and inbuckling of the ligamentum flavum, thus facilitating surgical planning, while radiographs and computed tomography (CT) provide complimentary information. Electrophysiology techniques are primarily used to rule out competing diagnoses. However, signal change and measures of cord compression on conventional MRI have limited utility to characterize the degree of tissue injury, which may be helpful for diagnosis, prognostication, and repeated assessments to identify deterioration. Early translational studies of quantitative imaging and electrophysiology techniques show potential of these methods to more accurately reflect changes in spinal cord microstructure and function.

CONCLUSION

Currently, clinical management of DCM relies heavily on anatomical MRI, with additional contributions from radiographs, CT, and electrophysiology. Novel quantitative assessments of microstructure, perfusion, and function have the potential to transform clinical practice, but require robust validation, automation, and standardization prior to uptake.

Predictive model for achieving good clinical and radiographic outcomes at one-year following surgical correction of adult cervical deformity

Background

For cervical deformity (CD) surgery, goals include realignment, improved patient quality of life, and improved clinical outcomes. There is limited research identifying patients most likely to achieve all three.

Objective

The objective is to create a model predicting good 1-year postoperative realignment, quality of life, and clinical outcomes following CD surgery using baseline demographic, clinical, and radiographic factors.

Methods

Retrospective review of a multicenter CD database. CD patients were defined as having one of the following radiographic criteria: Cervical sagittal vertical axis (cSVA) >4 cm, cervical kyphosis/scoliosis >10°° or chin-brow vertical angle >25°. The outcome assessed was whether a patient achieved both a good radiographic and clinical outcome. The primary analysis was stepwise regression models which generated a dataset-specific prediction model for achieving a good radiographic and clinical outcome. Model internal validation was achieved by bootstrapping and calculating the area under the curve (AUC) of the final model with 95% confidence intervals.

Results

Seventy-three CD patients were included (61.8 years, 58.9% F). The final model predicting the achievement of a good overall outcome (radiographic and clinical) yielded an AUC of 73.5% and included the following baseline demographic, clinical, and radiographic factors: mild-moderate myelopathy (Modified Japanese Orthopedic Association >12), no pedicle subtraction osteotomy, no prior cervical spine surgery, posterior lowest instrumented vertebra (LIV) at T1 or above, thoracic kyphosis >33°°, T1 slope <16 and cSVA <20 mm.

Conclusions

Achievement of a positive outcome in radiographic and clinical outcomes following surgical correction of CD can be predicted with high accuracy using a combination of demographic, clinical, radiographic, and surgical factors, with the top factors being baseline cSVA <20 mm, no prior cervical surgery, and posterior LIV at T1 or above.

Correlation Analysis for Selection of Microtitanium Plates with Different Specifications for Use in a Cervical Vertebral Dome Expansion Laminoplasty

Objective

To analyze correlations between the selection of microtitanium plates with different specifications for use in a cervical vertebral dome expansion laminoplasty.

Methods

Sixteen patients that underwent the cervical vertebral dome expansion laminoplasty with a cervical spinal stenosis angioplasty procedure for treatment of their cervical spinal cords were recruited at our hospital. From February 2017 to September 2018, medical records confirmed that all patients underwent cervical CT and MRI tests pre‐ and postsurgery. The anteroposterior diameter of the spinal canal, changes in the cross‐sectional area of the spinal canal, and the pre‐ and postsurgery distance of the cervical spinal cord after applying microtitanium plates with different lengths were measured by Mimics version 17.0 software (Materialise NV, Leuven, Belgium). A statistical regression and correlation analysis of relevant specification parameters of the microtitanium plate was then studied.

Results

As the size of the microtitanium plate increased, we found that the cross‐sectional area of cervical spinal canal and distance between the descendants of the lamina and the distance of cervical spinal cord concordantly increased, and these data changes linearly. The regression equation associated with sagittal diameter, cross‐sectional area, and posterior movement distance of the cervical spinal cord was obtained.

Conclusion

According to the correlation analysis of imaging data changes, the regression equation was obtained to guide the selection of microtitanium plates with appropriate specifications in a cervical vertebral dome expansion laminoplasty.

Epidemiological study of cervical cord compression and its clinical symptoms in community-dwelling residents

BACKGROUND

Degenerative compressive myelopathy (DCM) is caused by cervical cord compression. The relationship between the magnitude and clinical findings of cervical cord compression has been described in the literature, but the details remain unclear. This study aimed to clarify the relationship between the magnitude and clinical symptoms of cervical cord compression in community-dwelling residents.

METHODS

The present study included 532 subjects. The subjective symptoms and the objective findings of one board-certified spine surgeon were assessed. The subjective symptoms were upper extremity pain and numbness, clumsy hand, fall in the past 1 year, and subjective gait disturbance. The objective findings were: Hoffmann, Trömner, and Wartenberg signs; Babinski's and Chaddock's signs; hyperreflexia of the patellar tendon and Achilles tendon reflexes; ankle clonus; Romberg and modified Romberg tests; grip and release test; finger escape sign; and grip strength. Using midsagittal T2-weighted magnetic resonance imaging, the anterior-posterior (AP) diameters (mm) of the spinal cord at the C2 midvertebral body level (DC2) and at each intervertebral disc level from C2/3 to C7/T1 (DC2/3-C7/T1) were measured. The spinal cord compression ratio (R) for each intervertebral disc level was defined and calculated as DC2/3-C7/T1 divided by DC2. The lowest R (LR) along C2/3 to C7/T1 of each individual was divided into 3 grades by the tertile method. The relationship between LR and clinical symptoms was investigated by trend analysis.

RESULTS

The prevalence of subjective gait disturbance increased significantly with the severity of spinal cord compression (p = 0.002812), whereas the other clinical symptoms were not significantly related with the severity of spinal cord compression.

CONCLUSIONS

The magnitude of cervical cord compression had no relationship with any of the neurologic findings. However, subjective gait disturbance might be a better indicator of the possibility of early stage cervical cord compression.

Tracking White and Gray Matter Degeneration along the Spinal Cord Axis in Degenerative Cervical Myelopathy

This study aims to determine tissue-specific neurodegeneration across the spinal cord in patients with mild-moderate degenerative cervical myelopathy (DCM). Twenty-four mild-moderate DCM and 24 healthy subjects were recruited. In patients, a T2-weighted scan was acquired at the compression site, whereas in all participants a T2*-weighted and diffusion-weighted scan was acquired at the cervical level (C2-C3) and in the lumbar enlargement (i.e., rostral and caudal to the site of compression). We quantified intramedullary signal changes, maximal canal and cord compression, white (WM) and gray matter (GM) atrophy, and microstructural indices from diffusion-weighted scans. All patients underwent clinical (modified Japanese Orthopaedic Association; mJOA) and electrophysiological assessments. Regression analysis assessed associations between magnetic resonance imaging (MRI) readouts and electrophysiological and clinical outcomes. Twenty patients were classified with mild and 4 with moderate DCM using the mJOA scale. The most frequent site of compression was at the C5-C6 level, with maximum cord compression of 38.73% ± 11.57%. Ten patients showed imaging evidence of cervical myelopathy. In the cervical cord, WM and GM atrophy and WM microstructural changes were evident, whereas in the lumbar cord only WM showed atrophy and microstructural changes. Remote cervical cord WM microstructural changes were pronounced in patients with radiological myelopathy and associated with impaired electrophysiology. Lumbar cord WM atrophy was associated with lower limb sensory impairments. In conclusion, tissue-specific neurodegeneration revealed by quantitative MRI is already apparent across the spinal cord in mild-moderate DCM before the onset of severe clinical impairments. WM microstructural changes are particularly sensitive to remote pathologically and clinically eloquent changes in DCM.

Can Morphometric Analysis of Cervical Spondylotic Myelopathy Be a Tool for Surgical Outcome Prediction?

BACKGROUND

Cervical spondylotic myelopathy (CSM) is one of the leading causes of degenerative cervical myelopathy and the most common cause of spinal cord dysfunction in the elderly worldwide. Although there is emerging evidence that most patients improve after surgery, the key clinical and imaging factors predicting outcome remain uncertain. Our purpose is to evaluate preoperative and postoperative morphometric parameters on magnetic resonance imaging and their relation with neurological outcome at discharge and at 12-month follow-up.

METHODS

Morphometric features (volume, area, and antero-posterior diameter of the major stenotic section) were acquired by manual segmentation of the spinal canal using OsiriX open-source software and confronted with neurological outcome (at discharge and 12 months after surgery) using Nurick's scale.

RESULTS

Fifty-five patients (21 females and 34 males) with a mean age of 64.89 ± 11.95 years were analyzed. Recovery ratio was 2.44% ± 2.40% at discharge and 11.74% ± 2.50% at follow-up. Statistical analysis revealed a significant difference (P < .001) between Nurick's scale at admission versus discharge, at discharge versus follow-up at 1 year, and between admission and follow-up at 1 year. Morphometric changes (difference and ratio) between preoperative and postoperative measurements were also statistically significant (P < .001, paired samples t test). When linear regression was applied, volume difference was shown to have an influence on clinical improvement (P < .05; R = 0.519). Linear regression was also applied using recovery ratio at discharge and follow-up as dependent variables, with the same conclusion: volume difference between preoperative and postoperative measurements correlates with outcome improvement at 1 year after surgery.

CONCLUSIONS

Acquisition of morphometric features might be useful in predicting surgical outcome in patients with CSM. This information can be used to inform patients of their long-term postoperative prognosis in the future with more accurate and standardized measurements.

Impact of various MRI signal intensity changes on radiological parameters, the neurological status, and surgical outcomes in degenerative cervical myelopathy

STUDY DESIGN

A retrospective study of prospectively collected date.

PURPOSE

The present study aimed to identify patient characteristics, radiological factors, the neurological status, and postoperative outcomes associated with MRI signal intensity changes in degenerative cervical myelopathy (DCM).

MATERIAL AND METHOD

One hundred and fourteen DCM patients who underwent posterior decompression surgeries were enrolled. Pre- and postoperative (12 months) Japanese Orthopedic Association (JOA) scores, cervical alignment and balance on X rays, the cross-sectional area of the spinal cord (CSA) in kinematic CT myelography (CTM). The recovery rate (RR) of the total JOA score and those specific for the upper and lower limb items were evaluated. MRI included T1-weighted imaging (WI) and T2WI. Patients were classified into two groups for a univariate analysis according to the presence or absence of a high signal intensity (HIS) in the sagittal view on T2WI, a low signal intensity (LSI) in the sagittal view on T1WI, the distribution of HSI at a single or multiple levels, and the presence or absence of the snake eye appearance. A multiple logistic regression analysis (MLRA) was performed to identify factors associated with signal intensity changes on MRI.

RESULTS

Ninety-six patients (84.3%) were classified into HIS changes in the sagittal view on T2WI. The group with multilevel HSI showed significantly lower RR specific for the lower extremity JOA score (30.8% vs 47.7%; P = 0.016). The snake eye-positive group showed a significantly inferior RR specific for the upper extremity JOA score (40.1% vs 53.2%; P = 0.04). In MLRA, LSI changes on T1WI revealed small CSAF (P = 0.02, Odds ratio; 0.77, 95%CI:0.61-0.97), while HSI changes on T2WI revealed a small CSAF (P = 0.008, Odds ratio;1.36, 95%CI:1.08-1.72) and large C2-7 angle during extension (P = 0.009, Odds ratio;0.73, 95%CI:0.58-0.92). CSAF correlated with multilevel HSI changes (P = 0.006, Odds ratio;0.78, 95%CI:0.66-0.93). The snake eye appearance correlated with CSAF (P = 0.006, Odds ratio;0.78, 95%CI:0.66-0.93) and the duration of disease (P = 0.05, Odds ratio;1.01, 95%CI:1.0-1.03).

CONCLUSION

Severe and poorly compensated spinal cord compression during neck flexion may cause signal intensity changes. The snake eye appearance may be useful as a sign of the inferior postoperative recovery of upper limb function, and multilevel HSI as a sign of the inferior postoperative recovery of lower limb function.

Predictive effect of cervical spinal cord compression and corresponding segmental paravertebral muscle degeneration on the severity of symptoms in patients with cervical spondylotic myelopathy

BACKGROUND CONTEXT

Previous studies have found that cervical sagittal parameters and spinal cord compression are important risk factors for cervical spondylotic myelopathy (CSM). An increasing number of scholars believe that cervical muscle condition is also one of the factors affecting the severity of symptoms in affected patients.

PURPOSE

To determine whether: the degree of corresponding segmental paravertebral muscle degeneration is related to the severity of symptoms in patients with CSM; the degree of cervical spinal cord compression can predict the severity of symptoms in patients with CSM.

STUDY DESIGN

A retrospective study.

PATIENT SAMPLE

From January 2015 to January 2019, 121 patients with CSM were enrolled.

OUTCOME MEASURES

The visual analog scale (VAS), neck disability index (NDI) and modified Japanese Orthopedic Association (mJOA) were used to assess cervical spinal function and quality of life.

METHODS

From January 2015 to January 2019, 121 patients with CSM were enrolled. The inclusion criterion was the presence of complete cervical lateral radiography and magnetic resonance imaging (MRI) data. The following radiographic parameters were measured: (1) C0-C2 Cobb angle; (2) C2-C7 Cobb angle (CL); (3) T1 slope (T1S); (4) neck tilt (NT); (5) C2-C7 sagittal vertical axis (SVA); and (6) T1S-CL. The following MRI parameters were measured: (1) up(low)-fat/muscle; (2) up(low)-fat/centrum; (3) up(low)-muscle/centrum; (4) cervical cord compression index (CCI); (5) S-index; and (6) cervical spinal cord compression area ratio (S0/S1). The VAS, NDI and mJOA were used to assess cervical spinal function and quality of life. The patients were divided into 2 groups according to the mJOA score: group A (mild-moderate symptom group, mJOA score≥12 points) and group B (severe symptom group, mJOA score<12 points). The Pearson correlation coefficient was used to assess the correlations between cervical sagittal parameters, MRI parameters and functional scores. Logistic regression analysis and ROC curve analysis were performed to identify independent risk factors and critical values.

RESULTS

In patients with CSM, the VAS score is positively correlated with NT, up-fat/centrum, S-index and S0/S1. The NDI is positively correlated with NT, up-fat/muscle, up-fat/centrum, S-index, and S0/S1 and negatively correlated with C0-2N and CL. The mJOA score is positively correlated with CL and negatively correlated with C2-7 SVA, CCI, S-index, and S0/S1. Thus, corresponding segmental paravertebral muscle degeneration has relevance to neck pain, but it is not related to limb weakness, neurological dysfunction, gait impairment, sensation or bladder/bowel function dysfunction. Through mJOA score grouping and binary logistic regression analysis, we found that S0/S1 is the only independent risk factor for severe symptoms in patients with CSM. When S0/S1>0.295, the clinical symptoms of patients are more severe. Thus, in clinical practice, when the degree of spinal cord compression exceeds 30%, the clinical symptoms are more severe.

CONCLUSIONS

In patients with CSM, corresponding segmental paravertebral muscle degeneration has relevance to neck pain, but it does not relate to limb weakness, neurological dysfunction, gait impairment, sensation or bladder/bowel function dysfunction. Cervical spinal cord compression is the only independent risk factor;when the degree of spinal cord compression exceeds 30%, the clinical symptoms are more severe.

Increased signal intensity on postoperative T2-weighted axial images in cervical spondylotic myelopathy: Patterns of changes and associated impact on outcomes

Although T2-weighted axial magnetic resonance imaging (MRI) has strength in demonstrating morphologic characteristics of the spinal cord in cervical spondylotic myelopathy (CSM), no study has investigated postoperative changes. We aimed to assess postoperative changes on T2-weighted axial MRI using the classification system based on axial imaging in cervical compressive myelopathy (Ax-CCM) and associated impact on outcome in CSM. In total, 250 patients with CSM who underwent decompressive surgery with preoperative and postoperative MRI were included. At first, we investigated the presence of increased signal intensity (SI) in cervical spinal cord on T2-weighted sagittal images. Next, the increased SI was assessed using Ax-CCM on T2weighted axial images. The classifications were type 0, no-signal abnormality; single-level type 1, diffuse; single-level type 2, fuzzy focal; single-level type 3, discrete focal; and two-level. The recovery rates (RRs) of modified Japanese Orthopaedic Association (mJOA) score were evaluated from 5 to 10 months postoperatively. Eighty-seven patients (34.8%) exhibited postoperative changes. Most of postoperative changes were in single-level type 1 and 2. Patterns of changes were resolution, reduced extent, or transition to discrete margin. The most common pattern was resolution in type 1 (23.9%) and transition to discrete margin in type 2 (46.5%). In each group, resolution showed the best RR, but insignificantly (p > 0.05).

Surgery for Degenerative Cervical Myelopathy: What Really Counts?

STUDY DESIGN

Retrospective study (data analysis).

OBJECTIVE

The purpose of this study was to assess the role of different factors on postoperative outcome of patients with degenerative cervical myelopathy (DCM).

SUMMARY OF BACKGROUND DATA

Ongoing degenerative changes of DCM lead to progressive neurological deficits. The optimal timing of surgical treatment is still unclear, especially in patients with mild DCM.

METHODS

Patients with DCM treated in our clinic between 2007 and 2016 were retrospectively analyzed. Pre- and postoperative neurological function was assessed by the modified Japanese Orthopaedic Association Score (mJOA Score) at different stages. The minimum clinically important difference (MCID) was used to evaluate the improvement after surgery. The comorbidities were recorded using the Charlson Comorbidity Index (CCI). Possible associations between age, sex, CCI, preoperative symptoms duration, high signal intensity (SI) on T2-weighted magnetic resonance imaging (MRI) with mJOA Score and MCID were analyzed using univariate analysis and multivariate regression models. Additionally, subgroup analysis was performed according to the severity of DCM (mild: mJOA Score ≥15 points; moderate: mJOA Score of 12-14 points; and severe: mJOA Score <12 points).

RESULTS

The mean age of the final cohort (n = 411) was 62.6 years (range: 31-96 years), 36.0% were females. High SI on T2-weighted MRI was detected in 60.3% of the cases. In the multivariate analysis, patients' age (P = 0.005), higher CCI (P = 0.001), and presence of high SI on T2-weighted MRI (P = 0.0005) were associated independently with lower pre- and postoperative mJOA Score and postoperative MCID. Subgroup analysis revealed age and high SI on T2-weighted MRI as predictors of pre- and postoperative mJOA. However, symptom duration did not influence neurological outcome according to the severity of DCM.

CONCLUSION

Surgery for DCM leads to significant functional improvement. However, better outcome was observed in younger individuals with lower CCI and absence of radiographic myelopathy signs. Therefore, DCM surgery, particularly before occurrence of high SI on MRI, seems to be essential for postoperative functional improvement regardless the above-mentioned confounders.Level of Evidence: 3.

Risk Factors for Poor Outcome of Cervical Laminoplasty: Multivariate Analysis in 505 Patients with Cervical Spondylotic Myelopathy

The risk factors for poor outcome after cervical laminoplasty in patients with cervical spondylotic myelopathy (CSM) were demonstrated. These findings suggest that advanced age, long-term CSM symptoms, and lower score of preoperative 10-second step test are risk factors for poor cervical laminoplasty outcomes in patients with CSM.

Study Design..

A prospective study.

Objective..

The aim of this study was to characterize the risk factors for poor outcome following cervical laminoplasty in patients with cervical spondylotic myelopathy (CSM).

Summary of Background Data..

Previous research has identified a variety of potential predictive factors that might affect outcomes after cervical laminoplasty. However, no study till date has assessed the effects of such risk factors, including internal medicine comorbidity and quantitative performance tests, on the outcome of laminoplasty in a large series of patients with CSM.

Methods..

A total of 505 consecutive patients with CSM (311 males; 194 females; mean age, 66.6 years; age range, 41–91 years) who underwent double-door laminoplasty were prospectively included. The average postoperative follow-up period was 26.5 months (range, 12–66 months). We evaluated the recovery rate (RR) on the basis of the Japanese Orthopaedic Association score. Logistic regression analysis was performed to identify the risk factors for poor outcome, which was defined as a postoperative RR of <50%. Relationship between outcome and various clinical and imaging predictors was examined.

Results..

Two hundred ninety-five patients had good outcomes with RR >50%, whereas 210 patients had poor outcomes with RR <50%. Compared with the good-outcome group, the poor-outcome group had a significantly higher prevalence of diabetes and hypertension and use of anticoagulant/antiplatelet agent and smoking history (P < 0.05). Multivariate logistic regression analysis showed independent risks associated with increased age (odds ratio [ORs]  = 1.029, 95% confidence interval [CI] = 1.004–1054, P = 0.023). Logistic regression analysis determined that symptom duration of CSM (OR = 1.017, 95% CI = 1.008–1.026, P < 0.001) and preoperative 10-second step test (OR = 0.922, 95% CI = 0.865–0.983, P = 0.013) were significant risk factors for poor outcome.

Conclusion..

These findings suggest that advanced age, long-term CSM symptoms, and lower score of preoperative 10-second step test are risk factors for poor outcome in patients with CSM.

Level of Evidence: 2

The association between cervical focal kyphosis and myelopathy severity in patients with cervical spondylotic myelopathy before surgery

PURPOSE

Cervical focal kyphosis could often be observed in patients with cervical spondylotic myelopathy (CSM). However, the association between it and myelopathy severity remains unclear. This study aims to elucidate the association between cervical focal kyphosis and myelopathy severity before surgery.

METHODS

A retrospective review of 191 consecutive patients treated for CSM from 2017 to 2019 was surveyed. Seven MRI and five radiographic parameters were measured, clinical parameters were included. Patients were divided into two sagittal focal angle groups (lordosis/kyphosis) and two disc herniation severity groups (severe/non-severe). The potential risk factors of myelopathy symptoms were analysed.

RESULTS

Significant correlations between cervical sagittal focal angles, several other imaging findings and myelopathy severity were found in both total patients (R² = 0.51, P < 0.001) and non-severe disc herniation patients (R² = 0.73, P < 0.001) in multivariate regression models. Compression ratio of spinal cord exhibited the strongest correlation with JOA scores (r = - 0.567, P < 0.001). Cervical focal angles on MRI exhibited a stronger negative correlation with JOA scores (r = - 0.429, P < 0.001) than did angles on the other three postures on radiographs. Dramatic differences in JOA scores could be found in patients with non-severe cervical disc herniation, when a subgroup analysis was performed between cervical lordosis group and more than 4° kyphosis group (14.2 ± 1.7 vs. 11.1 ± 1.7, P < 0.001).

CONCLUSION

Cervical focal kyphosis associates with severe myelopathy symptoms in patients with CSM, especially without severe disc herniation. This association may indicate an optimal cervical focal angle in surgical plan. It appeared feasible to assess both the cervical focal angles and spinal cord compression on supine MRI.

Risk factors for rapid progressive neurological deterioration in patients with cervical spondylotic myelopathy

Background

The rapid progressive cervical spondylotic myelopathy (rp-CSM) which had a course of CSM less than 1 month and suffered rapidly progressive neurological deterioration had few reports. Therefore, it is important for us to recognize the pathophysiology of CSM especially the rp-CSM. The study aimed to investigate the risk factors for rapidly progressive (rp) neurological deterioration in patients with cervical spondylotic myelopathy (CSM).

Methods

A total of 159 patients were reviewed and divided into an rp-CSM group and a chronic-CSM (c-CSM) group. Various clinical indexes, including age, sex, Japanese Orthopaedic Association (JOA) score, intramedullary MR T2-hyperintensity, congenital/degenerative spinal stenosis, and local type of ossification of the posterior longitudinal ligament (OPLL), were analyzed, and independent risk factors were investigated.

Results

Thirty-four of 159 patients (21.4%) were diagnosed with rp-CSM. All patients were followed up for a mean of 68.56 ± 14.00 months in the rp-CSM group and 62.66 ± 19.95 months in the c-CSM group. No significant difference was found in sex, mean age, smoking and drinking status, diabetes mellitus (DM), hypertension, surgery time, blood loss, JOA score, degenerative spinal stenosis, or OPLL (local). Univariate analyses demonstrated that rp-CSM patients tended to have MR T2-hyperintensity, longer hospital stay, shorter waiting time for surgery, more congenital spinal stenosis, and worse neurological function and to prefer more posterior surgeries than c-CSM patients. A multiple logistic regression analysis showed that congenital spinal stenosis and MR T2-hyperintensity were independently related to the presence of rp-CSM.

Conclusions

MR T2-hyperintensity and congenital spinal stenosis were risk factors for rp-CSM. Although neurological function deteriorates rapidly, early surgical decompression is recommended and can achieve good neurological recovery after surgery, indicating that rp-CSM could be a reversible condition.

Prediction of outcome following laminoplasty of cervical spondylotic myelopathy: Focus on the minimum clinically important difference

The minimum clinically important difference (MCID) of the Japanese Orthopaedic Association (JOA) score has been reported to be around 2.5 points in cervical myelopathy. This study sought to define significant predictive factors on achieving the MCID following laminoplasty in a large series of patients with cervical spondylotic myelopathy (CSM). A total of 485 consecutive patients with CSM (295 males and 190 females; mean age: 67.0 years; age range: 42-91 years) who underwent laminoplasty were prospectively enrolled. The average postoperative follow-up period was 26.6 months (range: 12-66 months). We calculated the achieved JOA score. The relationships between outcomes and various clinical and imaging predictors including comorbidity and quantitative performance tests were examined. Logistic regression analysis was conducted to identify the predictors correlated with a JOA score of 2.5 points or more. Clinically meaningful gains were exhibited in 299 patients (61.6%) with a JOA score of ≥2.5 points, whereas 186 patients (38.4%) achieved a JOA score of <2.5 points. Univariate logistic regression analysis showed the predictive factors with a shorter duration of CSM symptoms, lower preoperative JOA scores, absence of hypertension, no use of anticoagulant/antiplatelet agents, and nonsmoking status. Multivariate logistic regression analysis determined that the duration of CSM symptoms (odds ratio: 0.771, 95% confidence interval: 0.705-0.844; p < 0.01) was the only significant predictive factor for achieving JOA scores of ≥2.5 points. An important predictor of MCID achievement following laminoplasty was shorter duration of CSM symptoms.

Long-term Outcome Following Three-Level Stand-Alone Anterior Cervical Discectomy and Fusion: Is Plating Necessary?

Background:

Anterior cervical discectomy with fusion (ACDF) is a proven method for the treatment of selected patients. The necessity of use of an anterior plate is controversial. The article aims to assess the fusion rates (FRs) and long-term outcomes following three-level ACDF.

Materials and Methods:

Data were collected from the medical records of patients operated on due to degenerative cervical disease. All patients were treated with three-level ACDF employing polyether ether-ketone cages without anterior plating. Visual analog scale (VAS), neck disability index (NDI), and plain radiographs were used in the clinical and radiological postsurgery assessment. Fusion evaluation was performed according to the <1 mm motion between spinous processes rule. Subsidence was defined as a more than 2 mm decrease in the interbody height.

Results:

A total of 234 treated levels on 78 patients were assessed. The mean presurgery NDI score was 23.07 ± 4.86, with a mean disability of 46.03% ± 9.64. The mean presurgery VAS score of the neck was 7.58 ± 0.85, while VAS score of the arm was 7.75 ± 1.008. Post surgery, NDI stated no disability, while VAS score of the neck and arm showed no presence of pain. The mean FR was 19.50 ± 21.71 levels per month, with a peak from 3^rd to 6^th month. Presurgery evaluation showed 12 (15.38%) patients with a high T2 sequence signal. Magnetic resonance imaging screening detected 31 (39.24%) patients with coexisting cervical and lumbar findings. Post surgery, transient dysphagia was reported by 1 patient (1.28%), while subsidence was registered in 15 (6.41%) levels, situated in 12 patients (15.38%), most often at C_6-7 (66.6%). Clinical and radiological follow-up extended to 69.47 ± 11.45 months.

Conclusion:

Multilevel stand-alone ACDF is a safe, cost-effective procedure providing favorable clinical and radiological results with minimal complications. The incidence of subsidence is usually clinically insignificant and can be decreased with a careful surgical technique.

Magnetic resonance imaging and dynamic X-ray's correlations with dynamic electrophysiological findings in cervical spondylotic myelopathy: a retrospective cohort study

Background

Dynamic somatosensory evoked potentials (DSSEP) can be used to disclose abnormalities of ascending sensory pathways at dynamic positions and diagnose cervical spondylotic myelopathy (CSM). However, radiographic tests including magnetic resonance imaging (MRI) and dynamic X-ray are used much more widely in the management of CSM. Our study aims to clarify the correlations between several radiographic parameters and the DSSEP results, and further determine their reliability with clinical data.

Methods

We retrospectively enrolled 38 CSM patients with surgical intervention. DSSEP tests were performed before surgery. Amplitude ratios of DSSEP N13 and N20 waves at extension and flexion were calculated and recorded as N13_E, N20_E, N13_F, N20_F, respectively. Baseline severity was evaluated with the modified Japanese Orthopedic Association (mJOA) score and the Nurick grades. Prognosis was evaluated based on the 2-year recovery rate. Sagittal diameter and transverse areas of the cord and canal were measured and the the compressive ratios at the compressed site (Compression_Ratio), central (Central_Ratio), and 1/4-lateral points (1/4-Lateral_Compression_Ratio), and spinal cord/Canal Area Ratio were calculated. The intramedullary T2 hyperintensity patterns (Ax-CCM types) were also collected from MRI axial images. Dynamic X-rays were used to test for segmental instability of the cervical spine. The correlations between radiologic findings, DSSEP data, and clinical assessments were investigated.

Results

We found that DSSEP N13_E and N13_F correlated with the Compression_Ratio, Central_Ratio, 1/4-Lateral_Compression_Ratio (Pearson, p < 0.05) and Ax-CCM types (ANOVA, p < 0.05) in MRI axial images and cervical segmental instability in dynamic X-ray (t-test, p < 0.05). Apart from the 1/4-Lateral_Compression_Ratio, these radiographic parameters above also correlated with the baseline clinical assessments (Spearman or ANOVA or t-test, p < 0.05) and postoperative recovery rate (Pearson or ANOVA or t-test, p < 0.05).

Conclusions

We found that the preoperative Compression_Ratio, Central_Ratio and 1/4-Lateral_Compression_Ratio in MRI and cervical segmental instability in dynamic X-ray could reflect the dynamic neural dysfunction of the spinal cord. Different Ax-CCM types corresponded to different DSSEP results at extension and flexion, suggesting divergent pathophysiology. These radiographic parameters could help evaluate disease severity and predict postoperative prognosis.

Magnetization Transfer Ratio and Morphometrics of the Spinal Cord Associates with Surgical Recovery in Patients with Degenerative Cervical Myelopathy

OBJECTIVES

We assessed the prognostic value of the preoperative magnetization transfer ratio (MTR) and morphometrics of the spinal cord in patients with degenerative cervical myelopathy (DCM) in a longitudinal cohort study.

METHODS

Thirteen subjects with DCM underwent 3T magnetization transfer imaging. The MTR was calculated for the spinal cord regions and specific white matter tracts. Morphometric measures were extracted. Clinical (modified Japanese Orthopaedics Association [mJOA] and Nurick scale scores) and health-related quality of life scores were assessed before and after cervical decompression surgery. The association between the magnetic resonance imaging (MRI) metrics and postoperative recovery was assessed (Spearman's correlation). Receiver operating characteristics were used to assess the accuracy of MRI metrics in identifying ≥50% recovery in function.

RESULTS

Preoperative anterior cord MTRs were associated with recovery in mJOA scores (ρ = 0.608; P = 0.036; area under the curve [AUC], 0.66). Preoperative lateral cord MTR correlated with the neck disability index (ρ = 0.699; P = 0.011) and pain interference scale (ρ = 0.732; P = 0.007). Preoperative rubrospinal tract MTR was associated with mJOA score recovery (ρ = 0.573; P = 0.041; AUC, 0.86). Preoperative corticospinal tract and reticulospinal MTRs were related to recovery in pain interference scores (ρ = 0.591; P = 0.033; and ρ = 0.583; P = 0.035, respectively). Eccentricity of the cord was associated with Nurick scores (ρ = 0.606; P = 0.028) and mJOA scores (ρ = 0.651; P = 0.025; AUC, 0.92).

CONCLUSIONS

Preoperative MTR and eccentricity measurements of the spinal cord have prognostic value in assessing the response to surgery and recovery in patients with DCM. Advanced MRI and atlas-based postprocessing techniques can inform interventions and advance the healthcare received by patients with DCM.

Multidimensional assessment of cervical spondylotic myelopathy patients. Usefulness of a comprehensive score system

OBJECTIVE

Cervical spondylotic myelopathy (CSM) is caused by cervical spine degeneration and surgery may be beneficial, but selection for surgery might be challenging. We performed a multimodal analysis to assess predicting factors that may be useful to help surgeons in this choice.

PATIENTS AND METHODS

We retrospectively evaluated clinical, motor evoked potentials (MEP), and MRI data of patients who undergone surgery for CSM. Seventy-six consecutive patients (46 males) were enrolled. The median age was 65.5 [IQR: 57-71] years, and the duration of symptoms was 11 [8-13] months. A multivariate analysis in order to assess predictors of outcome and ROC curve analysis were performed.

RESULTS

Thirty patients (M:18, 39.5%) gained 6 or more points on mJOA and they were collected in good recovery group, whereas 46 patients (60.5%, M:28) showed a fair recovery. We developed a comprehensive score system (CSS) taking into account clinical, neurophysiological, and neuroradiological data. ROC curve analysis was performed to determine the discriminative power of four models derived from the multivariate logistic regression analysis for predictors of good outcome considering only clinical variables, MRI variables, and MEP variables or considering the comprehensive model, demonstrating a good accuracy of CSS model to predict outcome.

CONCLUSION

This study demonstrates that CSS model taking into consideration functional assessment by mJOA score, neurologic evaluation, cervical MRI, and MEP may be a feasible method to predict outcome in patients candidate to surgery, supporting surgeon's decisions both for those patients candidate to surgery and for patients in whom a "wait and see" approach could be proposed.

Short-term predictive potential of quantitative assessment of spinal cord impairment in patients undergoing French-door Laminoplasty for degenerative cervical myelopathy: preliminary results of an exploratory study exploiting intraoperative ultrasound data

BACKGROUND

To study the correlation of neurological function in degenerative cervical myelopathy (DCM) patients with quantitative assessment of spinal cord compression and impairment by intraoperative ultrasound imaging (IOUSI).

METHODS

Twenty-three patients who underwent French-Door laminoplasty for multilevel DCM were followed for 6 months. Modified Japanese Orthopaedic Association (mJOA) score and cervical MRI were assessed before surgery and at postoperative 6 months. IOUS, used to guide decompression, were recorded. The anteroposterior diameter (APD) and the gray values of the IOUSI hyperechogenicity of the midsagittal IOUSI at the narrowest level and at the lesion-free level, and the APD and traverse diameter at the traverse maximum compression level of IOUSI were measured. Maximum spinal cord compression (MSCC), compression rate (CR), and IOUSI gray value ratio (R_gray) were calculated. The appearance of preoperative T2W MRI increased signal intensity (ISI), and the signal change rate (SCR) on postoperative T2W MRI of 9 patients were also measured and calculated, and compared with that of IOUSI hyperechogenicity.

RESULTS

Average mJOA score increased significantly from 11.57 ± 2.67 before surgery to 15.39 ± 1.50 at 6 months after surgery, with an average recovery rate (RR) of 71.11 ± 22.81%. The difference between the appearance of preoperative T2W MRI ISI and IOUSI hyperechogenicity was not significant. Spearman correlation analysis found that the IOUSI R_gray were negatively correlated with the RR of mJOA score with a coefficient of - 0.77, and the IOUSI R_gray was not correlated with the postoperative MRI SCR.

CONCLUSIONS

In DCM patients, the gray values of IOUSI can be measured accurately. The IOUSI R_gray correlated with postoperative neurological recovery significantly.

The prediction of intraoperative cervical cord function changes by different motor evoked potentials phenotypes in cervical myelopathy patients

Background

Surgery is usually the treatment of choice for patients with cervical compressive myelopathy (CCM). Motor evoked potential (MEP) has proved to be helpful tool in evaluating intraoperative cervical spinal cord function change of those patients. This study aims to describe and evaluate different MEP baseline phenotypes for predicting MEP changes during CCM surgery.

Methods

A total of 105 consecutive CCM patients underwent posterior cervical spine decompression were prospectively collected between December 2012 and November 2016. All intraoperative MEP baselines recorded before spinal cord decompression were classified into 5 types (I to V) that were carefully designed according to the different MEP parameters. The postoperative neurologic status of each patient was assessed immediately after surgery.

Results

The mean intraoperative MEP changes range were 10.2% ± 5.8, 14.7% ± 9.2, 54.8% ± 31.9, 74.1% ± 24.3, and 110% ± 40 in Type I, II, III, IV, and V, respectively. There was a significant correlation of the intraoperative MEP change rate with different MEP baseline phenotypes (r = 0.84, P < 0.01). Postoperative transient new spinal deficits were found 0/31 case in Type I, 0/21 in Type II, 1/14 in Type III, 2/24 in Type IV, and 4/15 in Type V. No permanent neurological injury was found in our cases series.

Conclusions

The MEP baselines categories for predicting intraoperative cervical cord function change is proposed through this work. The more serious the MEP baseline abnormality, the higher the probability of intraoperative MEP changes, which is beneficial to early warning for the cervical cord injury.

Degenerative Cervical Myelopathy: Review of Surgical Outcome Predictors and Need for Multimodal Approach

Degenerative cervical myelopathy is the most common cause of spinal cord injury in the elderly population in the developed world, and it significantly affects the quality of life of patients and their caregivers. Surgery remains the only treatment option able to halt disease progression and provide neurological recovery for most patients. Although it has remained challenging to predict exactly who will experience improvement after surgery, increasingly it has been shown that clinical, imaging, and electrophysiological factors can predict, with relatively good capacity, those more likely to benefit. Clinically, the baseline neurological impairment appears to be strongly related to the outcome, and the magnetic resonance imaging findings of T1-weighted hypointensity and the length of T2-weighted hyperintensity appear to be the most prognostic. In this context, electrophysiology findings (both motor and sensory evoked potentials) have shown some predictive capacity. However, large studies are lacking. Although multivariate models have been conducted using clinical and magnetic resonance imaging data, no multimodal prediction models are available that encompass the predictive capacity of clinical, imaging, and electrophysiological data. In the present review, we examined the rationale for clinical, imaging, and electrophysiological usage in clinical practice and discussed a model of multimodal assessment for the management of degenerative cervical myelopathy.

Postoperative Resolution of MR T2 Increased Signal Intensity in Cervical Spondylotic Myelopathy: The Impact of Signal Change Resolution on the Outcomes

STUDY DESIGN

A prospective comparative imaging study.

OBJECTIVE

This study investigated whether postoperative resolution of spinal cord increased signal intensity (ISI) reflected symptom improvement and surgical outcomes in cervical spondylotic myelopathy (CSM) patients.

SUMMARY OF BACKGROUND DATA

Although some CSM patients exhibit magnetic resonance imaging (MRI) ISI, its alteration and resolution have not been investigated. The association between postoperative ISI resolution and surgical outcomes in CSM patients remains controversial.

METHODS

A total of 505 consecutive CSM patients (311 males; 194 females) aged a mean of 66.6 years (range, 41-91) were enrolled. All were treated with laminoplasty and underwent MRI scans preoperatively and after an average of 26.5 months postoperatively (range 12-66 months). ISI was classified pre- and postoperatively based on sagittal T2-weighted magnetic resonance images into Grade 0, none; Grade 1, light (obscure); and Grade 2, intense (bright). The patients' pre- and postoperative neurological statuses were evaluated using the Japanese Orthopedic Association scoring system for cervical myelopathy [Japanese Orthopedic Association (JOA) score] and other quantifiable tests, including the 10-s grip and release (10-s G&R) test and 10-s step test.

RESULTS

A total of 337 patients showed preoperative ISI. Among these, 42 (12.5%) showed postoperative ISI resolution, associated with better postoperative JOA score and recovery rate, 10-s G&R and 10-s step test scores than those who retained it. Patients with preoperative Grade 2 ISI had no postoperative ISI resolution. Patients with ISI improvement from Grade 1 to Grade 0 had better outcomes than those with ISI worsening from Grade 1 to Grade 2.

CONCLUSION

Postoperative ISI resolution in CSM patients reflects postoperative symptoms and surgical outcomes. Patients who exhibit ISI resolution have better clinical outcomes.

LEVEL OF EVIDENCE

3.

Cervical Spondylotic Myelopathy: Natural Course and the Value of Diagnostic Techniques -WFNS Spine Committee Recommendations

Objective

This study presents the results of a systematic literature review conducted to determine most up-to-date information on the natural outcome of cervical spondylotic myelopathy (CSM) and the most reliable diagnostic techniques.

Methods

A literature search was performed for articles published during the last 10 years.

Results

The natural course of patients with cervical stenosis and signs of myelopathy is quite variable. In patients with no symptoms, but significant stenosis, the risk of developing myelopathy with cervical stenosis is approximately 3% per year. Myelopathic signs are useful for the clinical diagnosis of CSM. However, they are not highly sensitive and may be absent in approximately one-fifth of patients with myelopathy. The electrophysiological tests to be used in CSM patients are motor evoked potential (MEP), spinal cord evoked potential, somatosensory evoked potential, and electromyography (EMG). The differential diagnosis of CSM from other neurological conditions can be accomplished by those tests. MEP and EMG monitoring are useful to reduce C5 root palsy during CSM surgery. Notable spinal cord T2 hyperintensity on cervical magnetic resonance imaging (MRI) is correlated with a worse outcome, whereas lighter signal changes may predict better outcomes. T1 hypointensity should be considered a sign of more advanced disease.

Conclusion

The natural course of CSM is quite variable. Signal changes on MRI and some electrophysiological tests are valuable adjuncts to diagnosis.

Congenital Cervical Spine Stenosis in a Multicenter Global Cohort of Patients With Degenerative Cervical Myelopathy: An Ambispective Report Based on a Magnetic Resonance Imaging Diagnostic Criterion

BACKGROUND

Congenital spinal stenosis (CSS) of the cervical spine is a risk factor for acute spinal cord injury and development of degenerative cervical myelopathy (DCM).

OBJECTIVE

To develop magnetic resonance imaging (MRI)-based criteria to diagnose preexisting CSS and evaluate differences between patients with and without CSS.

METHODS

A secondary analysis of international prospectively collected data between 2005 and 2011 was conducted. We examined the data of 349 surgical DCM patients and 27 controls. Spinal canal and cord anteroposterior diameters were measured at noncompressed sites to calculate spinal cord occupation ratio (SCOR). Torg-Pavlov ratios and spinal canal diameters from radiographs were correlated with SCOR. Clinical and MRI factors were compared between patients with and without CSS. Surgical outcomes were also assessed.

RESULTS

Calculation of SCOR was feasible in 311/349 patients. Twenty-six patients with CSS were identified (8.4%). Patients with CSS were younger than patients without CSS (P = .03) and had worse baseline severity as measured by the modified Japanese Orthopedic Association score (P = .04), Nurick scale (P = .05), and Neck Disability Index (P < .01). CSS patients more commonly had T2 cord hyperintensity changes (P = .09, ns) and worse SF-36 Physical Component scores (P = .06, ns). SCOR correlated better with Torg-Pavlov ratio and spinal canal diameter at C3 than C5. Patients with SCOR ≥ 65% were also younger but did not differ in baseline severity.

CONCLUSION

SCOR ≥ 70% is an effective criterion to diagnose CSS. CSS patients develop myelopathy at a younger age and have greater impairment and disability than other patients with DCM. Despite this, CSS patients have comparable duration of symptoms, MRI presentations, and surgical outcomes to DCM patients without CSS.

Recent advances in the management of cervical spondylotic myelopathy: bibliometric analysis and surgical perspectives

OBJECTIVE

Cervical spondylotic myelopathy (CSM) has become a prevalent cause of spinal cord dysfunction among the aging population worldwide. Although great strides have been made in spine surgery in past decades, the optimal timing and surgical strategy to treat CSM have remained controversial. In this article the authors aimed to analyze the current trends in studies of CSM and to summarize the recent advances of surgical techniques in its treatment.

METHODS

The PubMed database was searched using the keywords pertaining to CSM in human studies that were published between 1975 and 2018. Analyses of both the bibliometrics and contents, including the types of papers, authors, affiliations and countries, number of patients, and the surgical approaches were conducted. A systematic review of the literature was also performed with emphasis on the diagnosis and treatment of mild CSM.

RESULTS

A total of 1008 papers published during the span of 44 years were analyzed. These CSM studies mainly focused on the natural history, diagnosis, and treatment, and only a few prospective randomized trials were reported. For the authors and affiliations, there was a shift of clustering of papers toward Asian countries in the past decades. Regarding the treatment for CSM, there was an exponential growth of surgical series published, and there was a trend toward slightly more anterior than posterior approaches through the past decade. Patients with CSM had increased risks of neurological deterioration or spinal cord injury with nonoperative management. Because surgery might reduce the risks, and early surgery was likely to be correlated with better outcomes, there was a trend toward attention to mildly symptomatic CSM.

CONCLUSIONS

There is emerging enthusiasm for research on CSM worldwide, with more publications originating in Asian countries over the past few decades. The surgical management of CSM is evolving continuously toward early and anterior approaches. More prospective investigations on the optimal timing and choices of surgery are therefore needed.

A comparison of radiological descriptions of spinal cord compression with quantitative measures, and their role in non-specialist clinical management

INTRODUCTION

Magnetic resonance imaging (MRI) is gold-standard for investigating Degenerative Cervical Myelopathy (DCM), a disabling disease triggered by compression of the spinal cord following degenerative changes of adjacent structures. Quantifiable compression correlates poorly with disease and language describing compression in radiological reports is un-standardised.

STUDY DESIGN

Retrospective chart review.

OBJECTIVES

1) Identify terminology in radiological reporting of cord compression and elucidate relationships between language and quantitative measures 2) Evaluate language's ability to distinguish myelopathic from asymptomatic compression 3) Explore correlations between quantitative or qualitative features and symptom severity 4) Investigate the influence of quantitative and qualitative measures on surgical referrals.

METHODS

From all cervical spine MRIs conducted during one year at a tertiary centre (N = 1123), 166 patients had reported cord compression. For each spinal level deemed compressed by radiologists (N = 218), four quantitative measurements were calculated: 'Maximum Canal Compromise (MCC); 'Maximum Spinal Cord Compression' (MSCC); 'Spinal Canal Occupation Ratio' (SCOR) and 'Compression Ratio' (CR). These were compared to associated radiological reporting terminology.

RESULTS

1) Terminology in radiological reports was varied. Objective measures of compromise correlated poorly with language. "Compressed" was used for more severe cord compromise as measured by MCC (p<0.001), MSCC (p<0.001), and CR (p = 0.002). 2) Greater compromise was seen in cords with a myelopathy diagnosis across MCC (p<0.001); MSCC (p = 0.002) and CR (p<0.001). "Compress" (p<0.001) and "Flatten" (p<0.001) were used more commonly for myelopathy-diagnosis levels. 3) Measurements of cord compromise (MCC: p = 0.304; MSCC: p = 0.217; SCOR: p = 0.503; CR: p = 0.256) and descriptive terms (p = 0.591) did not correlate with i-mJOA score. 4) The only variables affecting spinal surgery referral were increased MSCC (p = 0.001) and use of 'Compressed' (p = 0.045).

CONCLUSIONS

Radiological reporting in DCM is variable and language is not fully predictive of the degree of quantitative cord compression. Additionally, terminology may influence surgical referrals.

Risk Factors for Rapidly Progressive Neurological Deterioration in Cervical Spondylotic Myelopathy

STUDY DESIGN

A retrospective single-center study.

OBJECTIVE

This study sought to clarify the risk factors and to evaluate the surgical outcome in patients with rapidly progressive cervical spondylotic myelopathy (rp-CSM).

SUMMARY OF BACKGROUND DATA

CSM is a degenerative spine disease presenting a slow development of myelopathy. Some patients, however, show rapidly progressive neurological deterioration (especially gait disturbances) without any trauma. At present, there is little information about this condition.

METHODS

We studied 71 consecutive CSM patients (52 men, 19 women) with a mean age of 67.1 years, and the follow-up period was 1 year. Patients were divided into two groups: rp-CSM and chronic-CSM (c-CSM) groups. The Japanese Orthopaedic Association score and various clinical differences, including age, sex, comorbidity, the waiting period from symptomatic onset to surgery, cervical range of motion, and intramedullary MR T2-hyperintensity were analyzed, and independent risk factors were determined using a logistic regression analysis.

RESULTS

Eighteen of 71 patients (25.4%) were diagnosed with rp-CSM. There were no significant differences between the two groups with regard to age, sex, or cervical range of motion. In the rp-CSM group, the preoperative upper/lower extremities and bladder functions were worse, and the waiting period for surgery was shorter (rp-CSM 1.2 mo, c-CSM 25.7 mo). Patients with rp-CSM had a history of cardiovascular event (CVE) (rp-CSM 44.4%, c-CSM 15.1%) and presented with MR T2-hyperintensity (rp-CSM 94.4%, c-CSM 58.5%), especially at the C4/5 disc level. Independent risk factors were a history of CVE (odds ratio = 4.7) and MR T2-hyperintensity (odds ratio  = 12.5). The rp-CSM group showed a better neurological recovery after decompression surgery (the Japanese Orthopaedic Association recovery rate: rp-CSM 64.5%, c-CSM 40.7%).

CONCLUSION

A history of CVE and MR T2-hyperintensity were risk factors for rp-CSM. Despite rapid neurological deterioration, rp-CSM patients showed a good neurological recovery after surgery, and thus indicating that rp-CSM is a reversible condition.

LEVEL OF EVIDENCE

4.

Spinal cord swelling in patients with cervical compression myelopathy

Background

Intramedullary hyperintense lesions associated with spinal cord edema on T2-weighted MR images (T2WI) are rare findings in patients with cervical spondylosis and are poorly characterized. We investigated the clinical characteristics of spinal cord edema due to cervical spondylosis (SCECS).

Methods

In total, 214 patients with cervical spondylotic myelopathy who underwent surgery between April 2007 and March 2017 were divided into SCECS and non-SCECS groups with SCECS defined as follows: (1) intramedullary signal intensity (ISI) of the cervical spinal cord in sagittal T2WI extending to more than one vertebral body height; (2) “fuzzy” ISI, recognized as a faint intramedullary change with a largely indistinct and hazy border; and (3) a larger sagittal diameter of the spinal cord segment with ISI just above or below the cord compression area compared with areas of the cervical spine without ISI. Radiographic parameters, demographic characteristics, and the Japanese Orthopedic Association (JOA) surgical outcomes score were compared between the groups.

Results

Seventeen patients (7.9%) were diagnosed with SCECS. These patients were younger than those in the non-SCECS group [median (interquartile range), 64 (20) vs. 69 (15) years, respectively, p = 0.016], and the disease duration from onset to surgery was significantly shorter in the SCECS group than in the non-SCECS group [6 (7) vs. 20 (48) months, respectively]. No significant difference was observed between groups with respect to sex, radiologic findings, or surgical outcomes.

Conclusion

The disease showed an earlier onset and more rapid progression in the patients with SCECS than in those without SCECS.

Does three-grade classification of T2-weighted increased signal intensity reflect the severity of myelopathy and surgical outcomes in patients with cervical compressive myelopathy? A systematic review and meta-analysis

The three-grade classification of increased signal intensity (ISI) on T2-weighted magnetic resonance imaging (MRI) is used extensively in patients with cervical compressive myelopathy (CCM). However, the efficacy and value in the prediction of this classification are still unclear and no systematic review and meta-analysis have been conducted on this topic. The objective of this study is to investigate the efficacy and value in prediction of the three-grade classification of ISI on the severity of myelopathy and surgical outcomes. Randomized or non-randomized controlled studies using three-grade classification of ISI (grade 0, none; grade 1, light or obscure; and grade 2, intense or bright) in patients with CCM were sought in the following databases: PubMed, Embase, and Cochrane Library. The pooled Japanese Orthopedic Association (JOA)/modified JOA (mJOA) score, neuro-functional recovery rate, C2-C7 lordotic angle, and range of motion (ROM) were calculated. A total of 8 studies containing 1101 patients were included in this review. Patients in grade 0 had the highest preoperative and postoperative JOA/mJOA score and recovery rate, while those parameters for patients in grade 2 were the lowest. Nevertheless, no statistically significant difference was found regarding the preoperative C2-C7 lordotic angle and ROM among three grades. Our meta-analysis suggests that the three-grade classification of ISI on T2-weighted MRI can reflect the severity of myelopathy and surgical outcomes in patients with CCM. The higher ISI grade indicates more severe myelopathy and surgical outcomes. Overall, the three-grade classification of ISI is instructive and should be used universally.

Cervical spondylosis in patients presenting with "severe" myelopathy: Analysis of treatment by multisegmental spinal fixation - A case series

Background:

Surgical strategy of multisegmental spinal fixation that includes atlantoaxial joint for patients having cervical spondylosis-related symptoms of severe myelopathy is analyzed.

Objective:

Surgical outcome of patients presenting with “severe” symptoms of cervical myelopathy having multisegmental degenerative cervical spondylosis and treated by multisegmental spinal fixation is analyzed. Atlantoaxial joint was included in the fixation construct in majority of patients. No bone, soft tissue, osteophyte, or disc resection for decompression was done.

Materials and Methods:

Sixty-four patients having multisegmental cervical spondylosis who presented with symptoms of severe myelopathy were surgically treated during the period from March 2013 to December 2018. On the basis of the concept that instability is the primary cause of spinal degeneration, multisegmental spinal fixation was done in all patients. Atlantoaxial joint was included in the fixation construct in 48 patients. The levels of spinal fixation were determined on the basis of direct observation of facet joints and by manual manipulation and were guided by the presenting clinical features and radiological information. Clinical monitoring was done using Goel clinical grading, modified Japanese Orthopedic Association Score, and visual analog score parameters. Patient satisfaction index assessed the functional and symptomatic improvement.

Results:

During the follow-up that ranged from 6 to 75 months, all patients improved in their clinical status. Fifty-five (85.9%) patients could walk independently or with mild support.

Conclusions:

Multisegmental spinal fixation that includes atlantoaxial joint in most patients forms a rational treatment strategy for patients of cervical spondylosis presenting with severe symptoms of myelopathy.

The Relation between Cord Signal and Clinical Outcome after Anterior Cervical Discectomy in Patients with Degenerative Cervical Disc Herniation

Introduction

Cervical spondylotic myelopathy is a cervical cord compressive lesion that occurs as a result of the normal degenerative process which may cause magnetic resonance imaging (MRI) cord intensity changes that may worsen the clinical outcome even after successful anterior cervical decompression.

Objective

To assess the relation between MRI T2 Weighted images (T2 WI) hyperintense cord signal and clinical outcome after anterior cervical discectomy in patients with degenerative cervical disc herniation.

Materials and Methods

This is a retrospective observational study that was conducted on twenty-five patients with degenerative cervical disc prolapse associated with MRI T2WI hyperintense cord signal, at the Department of Neurosurgery, Qena University Hospital, South Valley University from August 2014 to December 2016. A complete clinical and radiological evaluation of the patients was done. Anterior cervical discectomy and fusion was done for all patients. Patients were clinically assessed preoperatively and postoperatively at 3, 6, and 12 months using Modified Japanese Orthopedic Association (MJOA) score. Radiographic assessment was done by preoperative and postoperative T2WI MRI. The statistical analysis was done using Statistical Package for the Social Sciences (SPSS) software (version 22.0).

Results

There were 25 patients included in the study; 16 (64%) females and 9 (36%) males. The mean age was 46.89 ± 7.52 standard deviation (SD) years with range from 26 to 64 years, 3 (12%) patients had worsened in the form of postoperative motor power deterioration, and 14 (56%) patients has no improvement and remain as preoperative condition. The remaining 8 (32%) patients had a reported postoperative improvement of symptoms and signs according to MJOA score. The mean follow-up period (in months) was 11 ± 2.34 (SD).

Conclusion

The presence of T2W hyperintense signal on preoperative MRI predicts a poor surgical outcome in patients with cervical disc prolapse. The regression of T2W ISI postoperatively correlates with better functional outcomes.

Is Preoperative Duration of Symptoms a Significant Predictor of Functional Outcomes in Patients Undergoing Surgery for the Treatment of Degenerative Cervical Myelopathy?

BACKGROUND

Preoperative duration of symptoms may significantly impact outcomes in patients treated surgically for degenerative cervical myelopathy (DCM).

OBJECTIVE

To (i) analyze whether duration of symptoms is associated with preoperative functional impairment, disability, and quality of life and (ii) determine the optimal timing for decompressive surgery.

METHODS

Patients with DCM were prospectively enrolled in either the AOSpine North American or International study at 26 global sites (n = 757). Postoperative functional impairment was evaluated at 1-yr using the modified Japanese Orthopaedic Association (mJOA) score. Change scores between baseline and 1-yr were computed for the mJOA. Duration of symptoms was dichotomized into a “short” and “long” group at several cut-offs. Analysis of covariance was used to evaluate differences in change scores on the mJOA between duration of symptoms groups in 4-mo increments.

RESULTS

Our cohort consisted of 424 men and 255 women, with a mean duration of symptoms of 26.1 ± 36.4 mo (0.25-252 mo). Duration of symptoms was not correlated with preoperative mJOA, Nurick, Neck Disability Index, or Short-Form (SF)-36 Physical and Mental Component Scores. Patients with a duration of symptoms shorter than 4 mo had significantly better functional outcomes on the mJOA than patients with a longer duration of symptoms (>4 mo). Thirty-two months was also a significant cut-off.

CONCLUSION

Patients who are operated on within 4 mo of symptom presentation have better mJOA outcomes than those treated after 4 mo. It is recommended that patients with DCM are diagnosed in a timely fashion and managed appropriately.

Alterations in Intramedullary T2-weighted Increased Signal Intensity following Laminoplasty in Cervical Spondylotic Myelopathy Patients: Comparison Between Pre- and Postoperative Magnetic Resonance Images

STUDY DESIGN

A prospective comparative imaging study.

OBJECTIVE

This study investigated whether the postoperative classification of and alterations in increased signal intensity (ISI) of the spinal cord reflected the postoperative severity of symptoms and surgical outcomes in cervical spondylotic myelopathy (CSM) patients.

SUMMARY OF BACKGROUND DATA

Although ISI on performing magnetic resonance imaging (MRI) is observed in CSM patients, alterations in ISI have not been investigated. The association of postoperative ISI with surgical outcomes in CSM patients remains controversial.

METHODS

Totally, 505 consecutive CSM patients (311 males) with a mean age of 66.6 (range, 41-91) years were enrolled. All were treated with laminoplasty and underwent MRI scans: preoperatively and after an average of 26.5 months postoperatively (range 12-66 months). ISI was classified pre- and postoperatively into three groups based on sagittal T2-weighted magnetic resonance images: Grade 0, none; Grade 1, light (obscure); and Grade 2, intense (bright). The patients' pre- and postoperative neurological statuses were evaluated using the Japanese Orthopaedic Association scoring system for cervical myelopathy (JOA score) and other quantifiable tests, including the 10-s grip and release (10-s G&R) test and 10-s step test.

RESULTS

Preoperatively, 168 patients had Grade 0 ISI, 169 had Grade 1, and 168 had Grade 2; postoperatively, 210 patients had Grade 0 ISI, 94 had Grade 1, and 201 had Grade 2. Patients with postoperative Grade 0 ISI had a better postoperative JOA score, recovery rate, and 10-s G&R and 10-s step test scores than those with other grades. The postoperative ISI grade improved in 66 patients (13.1%), worsened in 57 (11.3%), and remained unchanged in 382 (75.6%).

CONCLUSION

Postoperative ISI partially reflects postoperative symptoms and surgical outcomes. Alterations in ISI were observed postoperatively in 123 patients (24.4%) and were not correlated with surgical outcomes.

LEVEL OF EVIDENCE

2.