Outcome of patients treated for cervical myelopathy. A prospective, multicenter study with independent clinical review

Tract-specific magnetization transfer ratio provides insights into the severity of degenerative cervical myelopathy

STUDY DESIGN

Cross-sectional study.

OBJECTIVES

This study's goal is to report whether Magnetization Transfer Ratio (MTR) can evaluate the severity of white matter (WM) injury in degenerative cervical myelopathy (DCM).

SETTING

Laureate Institute of Brain Research, USA; Department of Neurosurgery, University of Oklahoma Health Sciences Center, USA.

METHODS

27 DCM patients were aged-matched with 20 healthy controls (HC) and categorized into treatment groups based on modified Japanese Orthopedic Association (mJOA) severity (11 mild and 16 moderate/severe). Regional and tract MTRs were extracted from the two vertebral levels containing maximum compression within magnetization transfer images. MTR differences between groups were assessed using a one-way ANOVA or Kruskal-Wallis test. The association between MTR and mJOA measures was evaluated using Spearman's correlation.

RESULTS

Significant decreases in MTR were found between HC and moderate/severe groups in the overall (p = 0.0065) and ventral (p = 0.0009) WM regions; and ventral corticospinal (p = 0.0101), ventral reticulospinal (p = 0.0084), spinal lemniscus (p = 0.0079), and fasciculus cuneatus (p = 0.0219) tracts. The spinal lemniscus MTR also significantly decreased between HC and mild groups (p = 0.038). Ventral reticulospinal tract MTR correlated with upper (r = 0.439; p = 0.022) and lower (r = 0.386; p = 0.047) limb motor mJOA scores.

CONCLUSIONS

Significant tract-based MTR changes and correlations align with known DCM symptoms, are demonstrated to be lost at the regional level, and display the inhomogeneous compressive damage occurring within DCM spinal cords.

Satisfaction in surgically treated patients with degenerative cervical myelopathy: an observational study from the canadian spine outcomes and research network

BACKGROUND CONTEXT

Healthcare reimbursement is evolving towards a value-based model, entwined and emphasizing patient satisfaction. Factors associated with satisfaction after degenerative cervical myelopathy (DCM) surgery have not been previously established.

PURPOSE

Our primary objective was to ascertain satisfaction rates and satisfaction predictors at 3 and 12 months following surgical treatment for DCM.

DESIGN

This is a prospective cohort study within Canadian Spine Outcomes and Research Network (CSORN).

PATIENT SAMPLE

Patients in the study were surgically treated for DCM patients who completed 3-month and 12-month follow-ups within CSORN between 2015 and 2021.

OUTCOME MEASURES

Data analyzed included patient demographic, surgical variables, patient-reported outcomes (NDI, NRS-NP, NRS-AP, SF-12-MCS, SF-12-PCS, ED-5Q, PHQ-8), MJOA and self-reported satisfaction on a Likert scale.

METHODS

Multivariable regression analysis was conducted to identify significant factors associated with satisfaction, address multicollinearity and ensure predictive accuracy. This process was conducted separately for the 3-month and 12-month follow-ups.

RESULTS

Six hundred and sixty-three patients were included, with an average age of 60, and an even distribution across MJOA scores (mild, moderate, severe). At 3-month and 12-month follow-up, satisfaction rates were 86% and 82%, respectively. At 12 months, logistic regression showed the odds of being satisfied varied by +24%, -3%, -10%, -14%, +3%, and +12% for each 1-point change between baseline and 12 months in MJOA, NDI, NRS-NP, NRS-AP, SF-12-MCS, SF-12-PCS. Satisfaction increased 11-fold for each 0.1-point increased in ED-5Q from baseline to 12 months. At baseline, for every 1-point increase in SF-12-MCS, the odds of being satisfied increased by 7%. At 3 months, all PROs (except for NRS-AP change and baseline SF-12-MCS) predicted satisfaction. All logistic regression analyses demonstrated excellent predictive accuracy, with the highest 12-month AUC of 0.86 (95%CI = 0.81-0.90). No patient demographic or surgical factors influenced satisfaction.

CONCLUSION

Improvement in Patient Reported Outcomes and MJOA are strongly associated with patient satisfaction after surgery for DCM. The only baseline PRO associated with 12-months satisfaction was SF-12-MCS. No modifiable patient baseline characteristic or surgical variables were associated with satisfaction.

Current Status and Trends of Research on Cervical Spondylotic Myelopathy from the Perspective of Bibliometrics

This review was performed to analyze the research on cervical spondylotic myelopathy published during the past 25 years, summarize the developments in existing research, and predict future hotspots in the field. The goal is to provide a comprehensive overview and exploration of developments in this research area. A bibliometric analysis was performed using CiteSpace and VOSviewer to quantitatively and visually analyze relevant literature from Web of Science between 1998 and 2023. Co-occurrence analysis and co-citation analysis were conducted to evaluate papers, authors, journals, countries, and keywords. In total, 1886 papers were included. The overall publication output in this field increased throughout the review period. Stable author collaboration groups were formed, with the most influential author being Fehlings M.G. Japan and the United States contributed the highest number of publications. The predicted future research hotspots include risk factor analysis, outcome prediction, and machine learning. This study provides both an overview of the research trajectory in the field of cervical spondylotic myelopathy for scholars interested in this area, as well as offering insights and references for future research directions in the field.

Factors Predisposing Patients to Nonhome Discharge After Surgery for Degenerative Cervical Myelopathy: A Retrospective Analysis

OBJECTIVE

The objective of this study is to evaluate factors associated with discharge to subacute care after surgery for degenerative cervical myelopathy.

DESIGN

This is a retrospective chart review of adults who underwent cervical spine surgery for degenerative cervical myelopathy between 2014 and 2020 ( N = 135).

RESULTS

Patients discharged to a subacute setting were older (68.1 ± 8.6 vs. 64.1 yrs ± 8.8, P = 0.01), more likely to be unmarried (55.8% vs. 33.7% married, P = 0.01), and more likely to have Medicare or Medicaid (83.7% vs. 65.9% private insurance, P = 0.03) than patients discharged home. A posterior surgical approach was associated with discharge to a subacute setting (62.8% vs. 43.5% anterior approach, P = 0.04). A total of 87.8% of patients discharged to a subacute setting required moderate or maximum assistance for bed mobility versus 26.6% of patients discharged home ( P < 0.0001). Compared with patients discharged home, patients discharged to a subacute setting ambulated a shorter distance in their first physical therapy evaluation after surgery (8.9 ± 35.8 vs. 53.7 ± 61.78 m in the home discharge group, P < 0.0001).

CONCLUSIONS

Analysis of these factors may guide discussions about patient expectations for postoperative discharge placement.

T1 mapping in patients with cervical spinal canal stenosis with and without decompressive surgery: A longitudinal study

BACKGROUND AND PURPOSE

Cervical spinal canal stenosis (cSCS) is a common cause of spinal impairment in the elderly. With conventional magnetic resonance imaging (MRI) suffering from various limitations, high-resolution single-shot T1 mapping has been proposed as a novel MRI technique in cSCS diagnosis. In this study, we investigated the effect of conservative and surgical treatment on spinal cord T1 relaxation times in cSCS.

METHODS

T1-mapping was performed in 54 patients with cSCS at 3 Tesla MRI at the maximum-, above and below the stenosis. Subsequently, intraindividual T1-differences (ΔT1) intrastenosis were calculated. Twenty-four patients received follow-up scans after 6 months.

RESULTS

Surgically treated patients showed higher ΔT1 at baseline (154.9 ± 81.6 vs. 95.3 ± 60.7), while absolute T1-values within the stenosis were comparable between groups (863.7 ± 89.3 milliseconds vs. 855.1 ± 62.2 milliseconds). In surgically treated patients, ΔT1 decreased inverse to stenosis severity. After 6 months, ΔT1 significantly decreased in the surgical group (154.9 ± 81.6 milliseconds to 85.7 ± 108.9 milliseconds, p = .021) and remained unchanged in conservatively treated patients. Both groups showed clinical improvement at the 6-month follow-up.

CONCLUSIONS

Baseline difference of T1 relaxation time (ΔT1) might serve as a supporting marker for treatment decision and change of T1 relaxation time might reflect relief of spinal cord narrowing indicating regenerative processes. Quantitative T1-mapping represents a promising additional imaging method to indicate a surgical treatment plan and to validate treatment success.

Validating the preoperative Japanese Core Outcome Measures Index for the Neck and comparing quality of life in patients with cervical spondylotic myelopathy and ossification of the posterior longitudinal ligament by the patient-reported outcome measures

PURPOSE

This cross-sectional study serves two main purposes. Firstly, it aims to validate the preoperative Japanese Core Outcome Measures Index for the Neck (COMI-Neck) in patients with cervical spondylotic myelopathy (CSM) and ossification of the posterior longitudinal ligament (OPLL). Secondly, it seeks to elucidate differences in preoperative quality of life (QOL) between these two cervical pathologies using patient-reported outcome measures (PROMs).

METHODS

A total of 103 preoperative patients (86 with CSM and 17 with OPLL) scheduled for cervical spine surgery were included in the study. Validated PROMs, including the Japanese COMI-Neck, Neck Disability Index (NDI), EuroQol-5 Dimension-3 level (EQ-5D-3L), and SF-12v2, were used to assess QOL. Baseline demographic and clinical data were collected, and statistical analyses were performed to compare the PROMs between CSM and OPLL groups.

RESULTS

The Japanese COMI-Neck demonstrated good construct validity, with positive correlations with NDI and negative correlations with EQ-5D-3L and SF-12v2. Comparison of preoperative PROMs between CSM and OPLL groups revealed differences in age, body mass index, and EQ-5D-3L scores. The CSM group had higher NDI scores for concentration and lower EQ-5D-3L scores for self-care compared to the OPLL group.

CONCLUSIONS

This study validated the preoperative Japanese COMI-Neck in CSM and OPLL patients and identified specific QOL issues associated with each condition. The findings highlight the importance of considering disease-specific QOL and tailoring treatment plans accordingly. Further research should include postoperative assessments and a more diverse population to enhance generalizability.

Predictive Factors Associated with Chronic Neck Pain in Patients with Cervical Degenerative Disease: A Retrospective Cohort Study

Purpose

To explore the predictive factors of neck pain (NP) in patients with cervical degenerative disease by retrospectively analyzing their occupational and demographic characteristics and to provide a valuable reference for preventing and treating chronic NP.

Patients and Methods

We retrospectively reviewed the occupational and demographic data of patients with cervical degenerative disease who had undergone anterior cervical surgery between June 2021 and December 2022 at our center. The patients were divided into NP and no-NP groups based on whether they had chronic NP before surgery. Relevant occupational and demographic data from all patients were statistically analyzed, and all variables were made categorical. Forward stepwise logistic regression models were constructed for preoperative chronic neck pain to explore the possible risk factors associated with chronic neck pain.

Results

The differences in smoking, being an office worker, BMI, and disease types between NP and no-NP groups were statistically significant. In contrast, there were no statistically significant in age, sex, academic level, duration, and degeneration grade between the two groups. Moreover, further logistic regression analysis indicated that smoking, being an office worker, having an abnormal BMI, and cervical spondylotic radiculopathy (CSR) were related to chronic neck pain.

Conclusion

The present study indicated that smoking, being an office worker, having an abnormal BMI, and CSR were predisposing risk factors for NP associated with cervical degenerative disease. Although intervertebral disc degeneration is the pathology basis of NP, the degeneration grade was not related to the occurrence of NP in our current study. Therefore, quitting smoking, avoiding sedentariness, and maintaining a normal BMI may prevent NP to some extent.

Role of diffusion tensor imaging in stenotic and non-stenotic spinal canal

BACKGROUND AND PURPOSE

Cervical Spondylotic Myelopathy (CSM) is a gradually escalating spinal cord disturbance set in motion by the degenerative narrowing of the vertebral canal. Routine MRI may fail to detect the subtle early alterations of the cord. MRI Diffusion Tensor Imaging (DTI) possesses the potential to detect these changes. This study intends to estimate the potential of the DTI technique in non-stenotic & stenotic spinal canals in individuals affected with CSM.

METHODOLOGY

Sixty-four subjects who met the requirements of the inclusion criteria were incorporated into the investigation. All subjects underwent routine MRI sequences in addition to DTI of the cervical spine region. Scalars such as Fractional Anisotropy (FA), besides Apparent Diffusion Coefficient (ADC), were computed at each cervical intervertebral fibrocartilaginous disc level for all subjects. DTI fiber tractography was then performed to qualitatively assess the microstructural integrity of the tracts.

RESULTS

A noteworthy difference (p<0.05) was seen in the FA parameter and ADC parameter values between the stenotic and non-stenotic groups, with the non-stenotic group having a higher mean FA and a lower ADC than the stenotic group (at the level of stenosis). A significant difference in age was seen between both groups, with most of the patients in the stenotic group belonging to 40 years and above. Tractography helped in demonstrating the morphology of the fiber tracts.

CONCLUSION

DTI parameters, namely FA and ADC, are sensitive to damage to the white matter and can be used to detect microstructural changes in the cord. However, standardization of the protocol is necessary when imaging the spinal canal.

Anterior cervical corpectomy for the treatment of spondylotic myelopathy: results of a prospective double-armed study with a three-year follow-up

BACKGROUND

Since the first description in the 1950s, cervical spondylotic myelopathy (CSM) has posed many challenges to neurosurgeons and spine surgeons. Direct comparison among different operative approaches has failed to produce valuable results due to either an insufficient number of enrolled patients or a lack of standardization of baseline conditions. This prospective double-armed non-randomized study with a 3-year follow-up involved 80 patients with degenerative cervical myelopathy surgically and conservatively treated. The primary aim was to determine the efficacy of corpectomy in mild-moderate and severe CSM and to compare the outcomes of conservative and surgical treatment.

METHODS

Eighty patients were stratified into two arms, on the basis of the mJOA score: mild-moderate (mJOA ≥12) and severe myelopathy (mJOA score <12). Each arm was subdivided into two treatment groups (operative or conservative): A1, mild-moderate myelopathy treated with corpectomy; A2, mild-moderate myelopathy treated conservatively; B1, severe myelopathy treated with corpectomy; B2, severe cervical myelopathy treated conservatively. The clinical outcome was evaluated with the modified JOA score, timed 10-meter walk, Mehalic grade, motor evoked potentials, the SF-12, and further assessed by external observers blinded to the type of treatment.

RESULTS

No significant differences in the recovery rates were found between the A1 and A2 groups at 6 months, although better results were recorded in the surgical groups (A1 and B1) at 12 months and at the final follow-up, as suggested by the significantly higher recovery rates. Multivariate analysis showed an inverse correlation between the duration of symptoms and the recovery rate (P<0.0001). Moreover, the preoperative timed 10-meter walk (P<0.004), the preoperative hypointensity on T1-weighted MR images (P<0.001), a higher Mehalic grade (P<0.02), the pre-treatment MEP (P<0.002), and the preoperative spinal canal diameter (P<0.004) significantly influenced the recovery rate.

CONCLUSIONS

This prospective double-armed non-randomized study demonstrates that corpectomy is an effective and safe treatment, especially for severe forms of myelopathy. In mild-moderate conditions, a discrepancy between neurological improvement and expressed level of satisfaction was found. The present results also show that a multiparametric evaluation is crucial for proper patient selection for corpectomy.

Use of tissue sealant patch (TachoSil) in the management of cerebrospinal fluid leaks after anterior cervical spine discectomy and fusion

PURPOSE

The purpose of this study was to evaluate a fast, sutureless technique to repair anterior cervical dural tears. Anterior cervical discectomy and fusion (ACDF) is a commonly performed procedure for the treatment of cervical degenerative diseases. Although uncommon, incidental durotomy with cerebrospinal fluid (CSF) leak during ACDF is a potentially serious complication. Yet, its technical management for the prevention of CSF leak is controversial.

METHODS

Between September 2012 and June 2018 we encountered seven cases (2 female/5 male) presenting with intraoperative CSF leaks secondary to incidental dural tears during ACDF surgery. All the cases were surgically treated using a topical fibrin sealant patch (TachoSil) with high adesive strength and fibrin glue (Tisseel). Intraoperative source of leakage, time to leakage control, quantity of Sealant Sponge used and postoperative complications were evaluated.

RESULTS

Dural tears were tipically the result of dissection of adherent posterior longitudinal ligament and/or calcified disc from the cervical dural sac to allow full decompression of the spinal cord. Effective repair of dural tear defined as cessation of CSF leak after topical sealant agents application was achieved no later than one minute in all cases. Evident clinical and/or radiological postoperative CSF leak was used to determine the patient's postoperative result. Postoperative CSF leak was not evident during a minimum 6 months follow up.

CONCLUSIONS

In the present study, we have reported our experience with a new sealing technique to manage CSF leaks from iatrogenic cervical dural lacerations. Tachosil tissue sealant patch is a rapid sutureless technique that may help in repairing introperatively incidental dural tears, thus reducing the risk of postoperative CSF leaks. To our knowledge, this is the first series to report the use of Tachosil adhesive sealant patch for the treatment of incidental dural tears during anterior cervical discectomy.

The Utility of COMPASS-31 Questionnaire to Predict Autonomic Dysfunction in Patients With Cervical/Upper Thoracic Compressive Myelopathy

BACKGROUND

Patients with cervical/upper thoracic compressive myelopathy may have autonomic dysfunction. The composite autonomic severity score (CASS) is the gold standard test to detect autonomic dysfunction, and the self-rated composite autonomic system scale (COMPASS-31) questionnaire is a screening tool to diagnose autonomic dysfunction. This study compared the COMPASS-31 and modified CASS scores for the detection of autonomic dysfunction in patients with compressive myelopathy.

METHODS

Patients with cervical/upper thoracic compressive myelopathy scheduled for decompressive surgery completed a COMPASS-31 questionnaire and underwent autonomic function tests to calculate the modified CASS score before surgery.

RESULTS

Forty-two patients were included in the study; 19 (45.2%) had mild autonomic dysfunction, 5 (11.9%) had moderate autonomic dysfunction, and 18 (42.9%) had severe autonomic dysfunction. Median (interquartile range) of modified CASS and COMPASS-31 scores were 19 (6.33) and 3 (2.5), respectively. There was a positive correlation between modified CASS and COMPASS-31 scores ( r =0.43; P =0.004). Receiver operating characteristic curve analysis confirmed that COMPASS-31 had fair accuracy for prediction of moderate to severe autonomic dysfunction (area under the curve, 0.74; 95% confidence interval, 0.64-0.82; P =0.009). A cut-off of 30 for total COMPASS-31 score had a sensitivity of 52.2% and specificity of 89.5% to detect moderate to severe autonomic dysfunction, with positive and negative predictive values of 85.7% and 60.7%, respectively.

CONCLUSION

Patients with cervical/upper thoracic compressive myelopathy had varying degrees of autonomic dysfunction based on the modified CASS. There was a positive correlation between the modified CASS and COMPASS-31 questionnaire. A COMPASS-31 score of >30 30 could be utilized to predict moderate to severe autonomic dysfunction in patients with compressive myelopathy.

Quantitative evaluation of the spinal cord compression in patients with cervical spondylotic myelopathy using synthetic MRI

Objectives: This work aimed to investigate the feasibility and diagnostic value of synthetic MRI, including T1, T2 and PD values in determining the severity of cervical spondylotic myelopathy (CSM). Methods: All subjects (51 CSM patients and 9 healthy controls) underwent synthetic MRI scan on a 3.0T GE MR scanner. The cervical canal stenosis degree of subjects was graded 0-III based on the method of a MRI grading system. Regions of interest (ROIs) were manually drawn at the maximal compression level (MCL) by covering the whole spinal cord to generate T1_MCL, T2_MCL, and PD_MCL values in grade I-III groups. Besides, anteroposterior (AP) and transverse (Trans) diameters of the spinal cord at MCL were measured in grade II and grade III groups, and relative values were calculated as follows: rAP = AP_MCL/AP_normal, rTrans = Trans_MCL/Trans_normal. rMIN = rAP/rTrans. Results: T1_MCL value showed a decreasing trend with severity of grades (from grade 0 to grade II, p < 0.05), while it increased dramatically at grade III. T2_MCL value showed no significant difference among grade groups (from grade 0 to grade II), while it increased dramatically at grade III compared to grade II (p < 0.05). PD_MCL value showed no statistical difference among all grade groups. rMIN of grade III was significantly lower than that of grade II (p < 0.05). T2_MCL value was negatively correlated with rMIN, whereas positively correlated with rTrans. Conclusion: Synthetic MRI can provide not only multiple contrast images but also quantitative mapping, which is showed promisingly to be a reliable and efficient method in the quantitative diagnosis of CSM.

The Natural History of Degenerative Cervical Myelopathy

Degenerative cervical myelopathy (DCM) is the most frequent cause of spinal cord dysfunction and injury in the adult population and leads to significant loss of quality of life and economic impact from its associated medical care expenditures and loss of work. Surgical intervention is recommended for patients manifesting progressing neurological signs and symptoms of myelopathy, but the optimal management in individuals who have mild and clinically stable disease manifestations is controversial. Understanding the natural history of DCM is, thus, important in assessing patients and identifying those most appropriately indicated for surgical management. Despite the attempts to rigorously perform studies of the natural history of these patients, most published investigations suffer from methodological weaknesses or are underpowered to provide definitive answers. Investigations of particular patient subsets, however, provide some clinical guidance as to which patients stand most to benefit from surgery, and these may include those with lower baseline mJOA scores, evidence of segmental hypermobility, cord signal changes on MRI, abnormal somatosensory or motor-evoked potentials, or the presence of certain inflammatory markers. Clinicians should assess patients with mild myelopathy and those harboring asymptomatic cervical spinal cord compression individually when making treatment decisions and an understanding of the various factors that may influence natural history may aid in identifying those best indicated for surgery. Further investigations will likely identify how variables that affect natural history can be used in devising more precise treatment algorithms.

Review of Prospective Trials for Degenerative Cervical Myelopathy

Degenerative cervical myelopathy (DCM) is the leading cause of spinal cord dysfunction in adults. DCM refers to a collection of degenerative conditions that cause the narrowing of the cervical canal resulting in neurological dysfunction. A lack of high-quality studies and a recent increase in public health awareness has led to numerous prospective studies evaluating DCM. Studies evaluating the efficacy of surgical intervention for DCM can be characterized by the presence (comparative) or absence (noncomparative) of a nonoperative control group. Noncomparative studies predominate due to concerns regarding treatment equipoise. Comparative studies have been limited by methodological issues and have not produced consistent findings. More recent noncomparative studies have established the safety and efficacy of surgical intervention for DCM, including mild myelopathy. The optimal surgical intervention for DCM remains controversial. A recent randomized clinical trial comparing dorsal and ventral techniques found similar improvements in patient-reported physical function at early follow-up. Recent prospective studies have enriched our understanding of DCM and helped guide current treatment recommendations.

Classification of expert-level therapeutic decisions for degenerative cervical myelopathy using ensemble machine learning algorithms

Background

Therapeutic decisions for degenerative cervical myelopathy (DCM) are complex and should consider various factors. We aimed to develop machine learning (ML) models for classifying expert-level therapeutic decisions in patients with DCM.

Methods

This retrospective cross-sectional study included patients diagnosed with DCM, and the diagnosis of DCM was confirmed clinically and radiologically. The target outcomes were defined as conservative treatment, anterior surgical approaches (ASA), and posterior surgical approaches (PSA). We performed the following classifications using ML algorithms: multiclass, one-versus-rest, and one-versus-one. Two ensemble ML algorithms were used: random forest (RF) and extreme gradient boosting (XGB). The area under the receiver operating characteristic curve (AUC-ROC) was the primary metric. We also identified the variable importance for each classification.

Results

In total, 304 patients were included (109 conservative, 66 ASA, 125 PSA, and 4 combined surgeries). For multiclass classification, the AUC-ROC of RF and XGB models were 0.91 and 0.92, respectively. In addition, ML models showed AUC-ROC values of >0.9 for all types of binary classifications. Variable importance analysis revealed that the modified Japanese Orthopaedic Association score and central motor conduction time were the two most important variables for distinguishing between conservative and surgical treatments. When classifying ASA and PSA, the number of involved levels, age, and body mass index were important contributing factors.

Conclusion

ML-based classification of DCM therapeutic options is valid and feasible. This study can be a basis for establishing generalizable ML-based surgical decision models for DCM. Further studies are needed with a large multicenter database.

Comparing the Bridge-Type Zero-Profile Anchored Spacer (ROI-C) Interbody Fusion Cage System and Anterior Cervical Discectomy and Fusion (ACDF) with Plating and Cage System in Cervical Spondylotic Myelopathy

OBJECTIVE

To compare the clinical efficacy and radioactivity of the bridge-type zero-profile anchored spacer (ROI-C) interbody fusion cage and anterior cervical discectomy and fusion with plating and cage system (ACDF) for cervical spondylotic myelopathy (CSM).

METHODS

This is a retrospective contrastive study. We recruited 35 patients who received ROI-C (ROI-C group) and 34 patients who received ACDF (ACDF group), between January 2014 to January 2019, at our treatment center. The ROI-C group comprised of 11 males and 24 females with a mean age of 61.59 ± 8.21 years (range, 51-71 years). The ACDF group comprised of 12 males and 22 females with a mean age of 60.15 ± 7.52 years (range, 52-74 years). Neck Disability Index (NDI), Japanese Orthopaedic Association score (JOA), Odom's score, cervical Cobb angle, fusion rate, adjoining ossification, and dysphagia.

RESULTS

A total of 69 patients met the inclusion criteria, and these patients received more than two years of follow-up. There were significant differences in surgical duration (101 ± 22 min vs. 118 ± 29 min) and blood loss (102 ± 46 ml vs. 145 ± 58 ml) between two groups (P < 0.05). The JOA and NDI of these two groups of patients significantly improved, when compared with those before the operation (P < 0.05). Twenty-nine of 35 patients in the ROI-C group and 27 of 34 patients in ACDF group achieved good or excellent outcomes according to Odom's criteria. The cervical lordosis of both two groups significantly increased, when compared with those before the operation (P < 0.05). In the ROI-C group, the postoperative fusion rate was 85.7% at the 3-month follow-up and 100% at the final follow-up. In the ACDF group, the postoperative fusion rate was 82.4% at the 3-month follow-up and 100% at the final follow-up. The dysphagia incidence of the ACDF group was higher than that of the ROI-C group postoperatively and at the one month after surgery (P < 0.05), but no significant difference was found in the incidence of dysphagia at final follow-up (P > 0.05).

CONCLUSION

Both ROI-C and ACDF achieved good therapeutic effects. However, ROI-C can reduce the operation time and postoperative complications.

Automatic Localization and Brand Detection of Cervical Spine Hardware on Radiographs Using Weakly Supervised Machine Learning

Purpose

To develop an end-to-end pipeline to localize and identify cervical spine hardware brands on routine cervical spine radiographs.

Materials and Methods

In this single-center retrospective study, patients who received cervical spine implants between 2014 and 2018 were identified. Information on the implant model was retrieved from the surgical notes. The dataset was filtered for implants present in at least three patients, which yielded five anterior and five posterior hardware models for classification. Images for training were manually annotated with bounding boxes for anterior and posterior hardware. An object detection model was trained and implemented to localize hardware on the remaining images. An image classification model was then trained to differentiate between five anterior and five posterior hardware models. Model performance was evaluated on a holdout test set with 1000 iterations of bootstrapping.

Results

A total of 984 patients (mean age, 62 years ± 12 [standard deviation]; 525 women) were included for model training, validation, and testing. The hardware localization model achieved an intersection over union of 86.8% and an F1 score of 94.9%. For brand classification, an F1 score, sensitivity, and specificity of 98.7% ± 0.5, 98.7% ± 0.5, and 99.2% ± 0.3, respectively, were attained for anterior hardware, with values of 93.5% ± 2.0, 92.6% ± 2.0, and 96.1% ± 2.0, respectively, attained for posterior hardware.

Conclusion

The developed pipeline was able to accurately localize and classify brands of hardware implants using a weakly supervised learning framework.Keywords: Spine, Convolutional Neural Network, Deep Learning Algorithms, Machine Learning Algorithms, Prostheses, Semisupervised Learning Supplemental material is available for this article. © RSNA, 2022See also commentary by Huisman and Lessmann in this issue.

Degenerative Cervical Myelopathy: Development and Natural History [AO Spine RECODE-DCM Research Priority Number 2]

STUDY DESIGN

Narrative review.

OBJECTIVES

To discuss the current understanding of the natural history of degenerative cervical myelopathy (DCM).

METHODS

Literature review summarizing current evidence pertaining to the natural history and risk factors of DCM.

RESULTS

DCM is a common condition in which progressive arthritic disease of the cervical spine leads to spinal cord compression resulting in a constellation of neurological symptoms, in particular upper extremity dysfunction and gait impairment. Anatomical factors including cord-canal mismatch, congenitally fused vertebrae and genetic factors may increase individuals' risk for DCM development. Non-myelopathic spinal cord compression (NMSCC) is a common phenomenon with a prevalence of 24.2% in the healthy population, and 35.3% among individuals >60 years of age. Clinical radiculopathy and/or electrophysiological signs of cervical cord dysfunction appear to be risk factors for myelopathy development. Radiological progression of incidental Ossification of the Posterior Longitudinal Ligament (OPLL) is estimated at 18.3% over 81-months and development of myelopathy ranges between 0-61.5% (follow-up ranging from 40 to 124 months between studies) among studies. In patients with symptomatic DCM undergoing non-operative treatment, 20-62% will experience neurological deterioration within 3-6 years.

CONCLUSION

Current estimates surrounding the natural history of DCM, particularly those individuals with mild or minimal impairment, lack precision. Clear predictors of clinical deterioration for those treated with non-operative care are yet to be identified. Future studies are needed on this topic to help improve treatment counseling and clinical prognostication.

Comparison of Laminoplasty vs. Laminectomy for Cervical Spondylotic Myelopathy: A Systematic Review and Meta-Analysis

OBJECTIVES

Laminoplasty (LP) and laminectomy (LC) with or without fusion are recommended as treatment procedures for cervical spondylotic myelopathy (CSM). The purpose of this study is to conduct a meta-analysis to analyze the results of CSM patients undergoing LP or LC surgery.

METHODS

We systematically and comprehensively searched Web of Science, Cochrane Library, PubMed, EMBASE, OVID, VIP database, Google Scholar, Chinese Bio-medicine Literature database, and China Scientific Journal Full-text database to July 2021 for randomized controlled trials (RCTs) and observational case series that compared LP and LC in patients with CSM. The main endpoints were the surgical process, radiographic outcomes, clinical outcomes, and surgical complications.

RESULTS

A total of 19 were included the inclusion criteria in this meta-analysis (n = 4,348 patients). There was no significant difference in range of motion (ROM), sagittal vertical axis (SVA), Japanese Orthopedic Association (JOA), Cobb angle, visual analog scale (VAS), cervical curvature index (CCI), Nurick score, Neck Dysfunction Index (NDI), and complications. LP was found to be superior than LC in terms of complications of C5 radiculopathy and surperficial infection.

CONCLUSION

Our results indicate that LP can achieve better results in C5 radiculopathy and superficial infection in surgical treatment of CSM compared with LC. Further high-quality research is warranted to further verify our findings.

SYSTEMATIC REVIEW REGISTRATION

PRISMA: CRD42018107070.

One Hundred Top Cited Articles in Cervical Myelopathy: A Bibliographic Analysis

STUDY DESIGN

A bibliometric review of the literature.

OBJECTIVES

The aim of this study was to identify the most highly cited articles relating to cervical myelopathy and to analyze the most influential articles.

SUMMARY OF BACKGROUND DATA

Over the past several decades, a lot of research has been conducted regarding the subject of cervical myelopathy. Although there are a large number of articles on this topic, to our knowledge, this is the first bibliometric analysis.

METHODS

A selection of search terms and keywords were inputted into the "Dimensions" database and the most highly cited articles in cervical myelopathy were selected from high impact factor journals. The top 100 articles were analyzed for year of publication, authorship, publishing journals, institution and country of origin, subject matter, article type, and level of evidence.

RESULTS

The 100 most cited articles in the topic of cervical myelopathy were published from 1956 to 2015. These articles, their corresponding authors, and number of citations are shown in Table 1. The number of citations ranged from 121 times for the 100th article to 541 times for the top article in a total of 20 journals. The most common topic was operative technique, whereas the journals which contributed the most articles were the Spine journal and the Journal of Neurosurgery.

CONCLUSION

Our study provided an extensive list of the most historically significant articles regarding cervical myelopathy, acknowledging the key contributions made to the advancement of this field.Level of Evidence: 5.

SEVERE CERVICAL MYELOPATHY: APPROACHES AND POSTOPERATIVE EVALUATION

ABSTRACT Objectives: To evaluate and compare the clinical evolution of surgical approaches used in patients with severe cervical myelopathy. Methods: Retrospective observational study in which 19 patients with myelopathy who underwent surgery were evaluated. Neurological assessments using the Frankel scale were conducted both preoperatively and one year following surgery, and the modified Japanese Orthopedic Association (JOA), Nurick, and Visual Analog Scale for pain (VAS) questionnaires were applied 1 year after the surgical procedure. Results: 89% of the participants were male and the average age was 63.9 years. No patient had postoperative neurological worsening, 12 patients (63.16%) had mild pain, and seven (36.84%) had moderate pain. The group with degenerative disease showed neurological improvement after surgery and the exclusively anterior approach was used in 84% of the cases, the exclusively posterior approach in 10% of the cases, and the dual approach in 6% of the cases. Conclusion: Surgical treatment has good results for inhibiting the unfavorable natural evolution of myelopathy within 1 year following surgery and promotes neurological improvement in degenerative cases, making it possible to use the anterior access route in most cases. Level of evidence III; Retrospective Study.

Degenerative Cervical Myelopathy: Clinical Presentation, Assessment, and Natural History

Degenerative cervical myelopathy (DCM) is a leading cause of spinal cord injury and a major contributor to morbidity resulting from narrowing of the spinal canal due to osteoarthritic changes. This narrowing produces chronic spinal cord compression and neurologic disability with a variety of symptoms ranging from mild numbness in the upper extremities to quadriparesis and incontinence. Clinicians from all specialties should be familiar with the early signs and symptoms of this prevalent condition to prevent gradual neurologic compromise through surgical consultation, where appropriate. The purpose of this review is to familiarize medical practitioners with the pathophysiology, common presentations, diagnosis, and management (conservative and surgical) for DCM to develop informed discussions with patients and recognize those in need of early surgical referral to prevent severe neurologic deterioration.

Incremental Diagnostic Value of Virtual Noncalcium Dual-Energy Computed Tomography for the Depiction of Cervical Disk Herniation Compared With Standard Gray-Scale Computed Tomography

OBJECTIVES

The aim of this study was to investigative the diagnostic accuracy of colored dual-energy computed tomography (CT) virtual noncalcium (VNCa) series for analyzing cervical disk herniation compared with standard gray-scale CT images, with magnetic resonance imaging (MRI) serving as standard of reference.

MATERIALS AND METHODS

Data from 57 patients who underwent noncontrast dual-source CT and 3.0-Tesla (T) MRI within 2 weeks between January 2017 and December 2018 were retrospectively analyzed. Five radiologists analyzed standard gray-scale dual-energy CT scans for the presence and degree of cervical disk herniation and spinal nerve root impingement. Readers reassessed scans after 8 weeks using colored VNCa series. Two experienced radiologists set the reference standard in consensus MRI reading sessions. Primary indices of diagnostic accuracy for both CT approaches were sensitivity and specificity, which were compared by application of the McNemar test.

RESULTS

A total of 57 patients (mean age, 64 ± 11 years; 30 women) were evaluated (337 intervertebral disks). Magnetic resonance imaging indicated a total of 103 cervical disk herniations. The VNCa reconstructions had higher overall sensitivity compared with gray-scale CT (487/515 [95%; 95% confidence interval (CI), 91%-98%] vs 392/515 [76%; 95% CI, 70%-83%]), as well as higher specificity (1107/1170 [95%; 95% CI, 90%-99%] vs 906/1170 [77%; 95% CI, 72%-82%]) for assessing cervical disk herniation (all P < 0.001). The VNCa reconstructions had higher diagnostic accuracy for analyzing spinal nerve root impingement in comparison with gray-scale CT (sensitivity, 195/230 [85%; 95% CI, 79%-90%] vs 115/230 [50%; 95% CI, 40%-59%]; specificity, 1430/1455 [98%; 95% CI, 94%-100%] vs 1325/1455 [91%; 95% CI, 88%-98%]; accuracy, 1625/1685 [96%; 95% CI, 93%-99%] vs 1440/1685 [86%; 95% CI, 82%-90%]; all P < 0.001).

CONCLUSIONS

Color-coded VNCa series improved the diagnostic accuracy for assessing cervical disk herniation and spinal nerve root impingement compared with standard gray-scale CT.

Spondylotic and Other Structural Myelopathies

PURPOSE OF REVIEW

This article highlights both common structural causes of myelopathy, such as spondylotic disease, and infrequent but treatable causes, such as syringomyelia, spinal cord herniation, arachnoid cyst, arachnoid band and web, epidural lipomatosis, Hirayama disease, and arachnoiditis.

RECENT FINDINGS

Neuroimaging improvements and availability have uncovered many structural abnormalities in the spines and spinal cords of patients who were asymptomatic or minimally symptomatic. Recent published clinical series have improved our knowledge of the natural history of structural abnormalities and the risks of intervention versus conservative management.

SUMMARY

Myelopathy from a suspected structural cause is a common reason for neurologic consultation. Correlation between the history, examination, and imaging are especially important to determine whether intervention is necessary or conservative management is the best option.

The Advent of Spinoplastics: Easing the Growing Global Disease Burden of Spinal Injury

Epidemiologic studies have demonstrated a growing global disease burden of pathologies affecting the vertebral column. Allograft or implant-based reconstruction and fusion surgeries have been the mainstay of treatment. The efficacy of various surgical methods and the reliability of instrumentation or implants to execute these surgeries continue to be debated in the literature. Advances such as the free-tissue transfer have improved postoperative measures; however, they add high operative risk. The advent of spinoplastics introduces a practical surgical model to augment these spinal surgeries using vascularized bone grafts. As this technique becomes more widespread, it can be utilized to ease the growing disease burden that spinal injury places on both patients and the health care system. Ultimately, it will ameliorate strains on health care resources, reduce health care costs, and improve patient outcomes and quality of life.

Perioperative Outcomes in 17,947 Patients Undergoing 2-Level Anterior Cervical Discectomy and Fusion Versus 1-Level Anterior Cervical Corpectomy for Treatment of Cervical Degenerative Conditions: A Propensity Score Matched National Surgical Quality Improvement Program Analysis

Objective

To compare the perioperative morbidity of 2-level anterior cervical discectomy and fusion (ACDF) with that of 1-level anterior cervical corpectomy and fusion (ACCF) for the treatment of cervical degenerative conditions.

Methods

A retrospective study of the 2005–2016 National Surgical Quality Improvement Program database for patients undergoing 2-level ACDF and 1-level ACCF was performed. Patient data included: age, sex, body mass index (BMI), functional status, and American Society of Anesthesiologists (ASA) physical status (PS) classification. Hospital data included: operative time and length of hospital stay (LOS). Thirty-day outcome data included: any, serious, and minor adverse events, return to the operating room, readmission, and mortality. After propensity matching for age, sex, ASA PS classification, functional status, and BMI, multivariate logistic regression analysis was used to compare outcomes between the 2 propensity-matched subcohorts. Finally, multivariate logistic regression that additionally controlled for operative time was performed to compare the 2 propensity-matched subcohorts.

Results

A total of 17,497 cases were identified, with 90.20% undergoing 2-level ACDF and 9.80% undergoing 1-level ACCF. Patients undergoing 2-level ACDF were younger, more likely to be female, had higher functional status, and had shorter operative time and LOS (p < 0.001). After propensity score matching, cases undergoing 1-level ACCF had a statistically significant higher rate of serious adverse events (p = 0.005). This difference was no longer significant after controlling for operative time.

Conclusion

While there was noted to be additional morbidity in 1-level ACCF cases relative to 2-level ACDF cases, the lack of difference once controlling for the surgical time supports using the procedure that best accomplishes the surgical objectives.

Influences of functional structures on the kinematic behavior of the cervical spine

BACKGROUND CONTEXT

A few studies have already investigated the influences of functional structures of the cervical spine on its biomechanical behavior. In most studies, this has been done by measuring the range of motion. However, this parameter lacks of qualitative information about the overall kinematic behavior, such as coupled motions or translations. These data are essential for future development of cervical implants and surgical techniques.

PURPOSE

An investigation of the influences of cervical structures on the kinematic behavior of the cervical spine under in vivo conditions is almost impossible due to ethical reasons. Therefore, an in vitro study was conducted which allowed the analysis of these influences using three-dimensional helical axes.

STUDY DESIGN/SETTING

An in vitro test applying pure moments on mono-segmental specimens was designed in order to investigate the influences of a series of structures on the kinematic behavior of the cervical spine using three-dimensional helical axes.

METHODS

In this study we extracted motion segments C2-C3, C4-C5, and C6-C7 from 6 human cadaveric specimens with an average age of 48 years. The specimens were carefully selected using X-ray images. For the in vitro experiments, seven states were defined. The first state represented the intact state of each specimen. The remaining six states correspond with the subsequent resection of the following structures in the given order: interspinous ligament, ligamentum flavum, facet capsule, vertebral arch, posterior longitudinal ligament, and anterior longitudinal ligament. Each state was tested using a well-established spine tester. Each test sequence included 3.5 quasi-static motion cycles in all three bending directions using pure moments of 1 Nm. All motions were recorded using a motion tracking device and six reflective markers which were attached to the specimens. The recordings were then used to calculate the 3D helical axes, which were matched with the X-ray images. Due to the small number of specimens, qualitative results, such as the helical axes, were analyzed using descriptive statistics.

RESULTS

In general, the overall range of motion was increased in all loading directions due to the resection steps. The least change in the kinematic behavior of the cervical spine was observed during flexion/extension. For lateral bending and axial rotation the greatest change in the pattern of the helical axes was observed during the resection of the vertebral arch. For some specimens, however, typical patterns regarding the orientation of the helical axes remained until the last state. For lateral bending, it could be observed that the deviation in the axes' orientation increased whereas for axial rotation it decreased.

CONCLUSION

Resection of the cervical ligaments are much less crucial than the removal of guiding structures such as the facet joint. Furthermore, coupled motions not only result from the orientations of the articular surfaces of the facet joints but also from the overall shape of the cervical vertebrae including the uncinate processes.

CLINICAL SIGNIFICANCE

It is well-known that coupled motions play a substantial role in cervical kinematics. However, the influences of cervical structures on the overall kinematic behavior of the cervical spine are not yet fully understood. Knowledge of these influences could help to reduce or even prevent iatrogenic degeneration after surgical intervention. Furthermore, the data provided by this study can be helpful for future developments of cervical implants as well as finite element models for more advanced numerical investigations.

DEGENERATIVE CERVICAL MYELOPATHY: A REVIEW OF CURRENT CONCEPTS

ABSTRACT Herbert von Luschka, a German anatomist, was the first to describe the developmental changes in the anatomical structures of the cervical spine. Degenerative cervical myelopathy (DCM) represents a collection of pathological entities that cause compression of the cervical spinal cord, resulting in a clinical syndrome typified by spasticity, hyperreflexia, pathologic reflexes, finger/hand clumsiness, gait disturbance and sphincter dysfunction. In the cervical spine, certain patients are more likely to have myelopathy due to a congenitally narrowed cervical spine canal. Degenerative changes are more common at C5 and C6 or C6 and C7 due to the increased motion at these levels. Additional contributors to canal narrowing are infolding of the ligamentum flavum, olisthesis, osteophytes, and facet hypertrophy. Myelopathy will develop in approximately 100% of patients with canal stenosis greater than 60% (less than 6 mm sagittal disc cord space). Classically it has an insidious onset, progressing in a stepwise manner with functional decline. Without treatment, patients may progress toward significant paralysis and loss of function. Treatment requires surgery with either anterior or posterior decompression of the area of narrowing, and probable fusion. Factors of a poor prognosis include symptoms lasting for more than 18 months, increased range of motion in the cervical spine, and female gender. In this study, we give an overview of the state-of-the-art in DCM, with a focus on the pathophysiology, clinical presentation, differential diagnosis, imaging evaluation, natural history, treatment options and complications. Level of evidence III; Review article.

Development and Validation of Cervical Prediction Models for Patient-Reported Outcomes at 1 Year After Cervical Spine Surgery for Radiculopathy and Myelopathy

STUDY DESIGN

Retrospective analysis of prospectively collected registry data.

OBJECTIVE

To develop and validate prediction models for 12-month patient-reported outcomes of disability, pain, and myelopathy in patients undergoing elective cervical spine surgery.

SUMMARY OF BACKGROUND DATA

Predictive models have the potential to be utilized preoperatively to set expectations, adjust modifiable characteristics, and provide a patient-centered model of care.

METHODS

This study was conducted using data from the cervical module of the Quality Outcomes Database. The outcomes of interest were disability (Neck Disability Index:), pain (Numeric Rating Scale), and modified Japanese Orthopaedic Association score for myelopathy. Multivariable proportional odds ordinal regression models were developed for patients with cervical radiculopathy and myelopathy. Patient demographic, clinical, and surgical covariates as well as baseline patient-reported outcomes scores were included in all models. The models were internally validated using bootstrap resampling to estimate the likely performance on a new sample of patients.

RESULTS

Four thousand nine hundred eighty-eight patients underwent surgery for radiculopathy and 2641 patients for myelopathy. The most important predictor of poor postoperative outcomes at 12-months was the baseline Neck Disability Index score for patients with radiculopathy and modified Japanese Orthopaedic Association score for patients with myelopathy. In addition, symptom duration, workers' compensation, age, employment, and ambulatory and smoking status had a statistically significant impact on all outcomes (P < 0.001). Clinical and surgical variables contributed very little to predictive models, with posterior approach being associated with higher odds of having worse 12-month outcome scores in both the radiculopathy and myelopathy cohorts (P < 0.001). The full models overall discriminative performance ranged from 0.654 to 0.725.

CONCLUSIONS

These predictive models provide individualized risk-adjusted estimates of 12-month disability, pain, and myelopathy outcomes for patients undergoing spine surgery for degenerative cervical disease. Predictive models have the potential to be used as a shared decision-making tool for evidence-based preoperative counselling.

LEVEL OF EVIDENCE

2.

T1 Mapping Quantifies Spinal Cord Compression in Patients With Various Degrees of Cervical Spinal Canal Stenosis

Age-related degeneration of the cervical spinal column is the most common cause of spinal cord lesions. T1 mapping has been shown to indicate the grade and site of spinal cord compression in low grade spinal canal stenosis (SCS). Aim of our study was to further investigate the diagnostic potential of a novel T1 mapping method at 0.75 mm resolution and 4 s acquisition time in 31 patients with various grades of degenerative cervical SCS. T1 mapping was performed in axial sections of the stenosis as well as above and below. Included subjects received standard T2-weighted MRI of the cervical spine (including SCS-grading 0-III), electrophysiological, and clinical examination. We found that patients with cervical SCS showed a significant difference in T1 relaxation times within the stenosis (727 ± 66 ms, mean ± standard deviation) in comparison to non-stenotic segments above (854 ± 104 ms, p < 0.001) and below (893 ± 137 ms, p < 0.001). There was no difference in mean T1 in non-stenotic segments in patients (p = 0.232) or between segments in controls (p = 0.272). Mean difference of the T1 relaxation times was significantly higher in grade III stenosis (234 ± 45) vs. in grade II stenosis (176 ± 45, p = 0.037) vs. in grade I stenosis (90 ± 87 ms, p = 0.010). A higher difference in T1 relaxation time was associated with a central efferent conduction deficit. In conclusion, T1 mapping may be useful as a tool for SCS quantification in all grades of SCS, including high-grade stenosis with myelopathy signal in conventional T2-weighted imaging.

Cervical Decompression Surgery Normalizes Gait Ground Reaction Forces in Patients With Cervical Spondylotic Myelopathy

STUDY DESIGN

Prospective cohort study.

OBJECTIVE

Investigate the effect of surgical decompression and fusion on gait ground reaction forces (GRFs) parameters in patients with cervical spondylotic myelopathy (CSM) and to compare these values to those of healthy controls.

SUMMARY OF BACKGROUND DATA

Surgical intervention to alleviate spinal cord compression is typically recommended in cases of CSM. While the primary aim of surgery is to halt disease progression, the literature suggests that some symptomatic improvement is often observed postoperatively. Gait analysis via measurement of GRFs is a particularly sensitive means of quantifying changes in ambulatory function, but no comprehensive analysis has been published in the setting of CSM.

METHODS

Forty patients with symptomatic CSM underwent gait analysis with measurement of horizontal and vertical GRFs before and 3 months after surgery. Thirty healthy controls (H) underwent the same battery of tests. Comparisons were made between the pre- and postoperative profiles of patients with CSM as well as to that of the control group.

RESULTS

Before surgery, patients with CSM exhibited disturbances in GRF magnitudes: significantly greater maximum weight acceptance (Pre: 113.7 vs. H: 101.1% body weight [BW], P = 0.040) and push off forces (Pre: 112.2 vs. H: 101.4% BW, P = 0.044), and timing: maximum weight acceptance occurred earlier while mid-stance (Pre: 15.8 vs. H: 17.8% gait cycle [GC], P = 0.018), toe-off (Pre: 65.0 vs. H: 62.9% GC, P = 0.001), braking (Pre: 55.6 vs. H: 54.2% GC, P = 0.003), and propulsion occurred (Pre: 11.9 vs. H: 10.6% GC, P = 0.011) later compared with healthy controls. Surgery improved all GRF parameters (P < 0.039), but postoperative gait profiles did not completely normalize to levels observed in the control group.

CONCLUSION

These observations combined with published data on gait muscle activation and gait patterns in CSM patients support the idea that patients with CSM have an altered gait profile consistent with a series of poorly controlled near falls. Surgical intervention was observed to produce improvements in but not complete resolution of these gait disturbances. These data provide a more comprehensive understanding of gait in the setting of CSM.

LEVEL OF EVIDENCE

3.

Cervical Spondylotic Myelopathy: When and Why the Cervical Corpectomy?

BACKGROUND

Cervical spondylotic myelopathy (CSM) is a degenerative disease that represents the most common spinal cord disorder in adults. The best treatment option has remained controversial. We performed a prospective study to evaluate the clinical, radiographic, and neurophysiologic outcomes for anterior cervical corpectomy in the treatment of CSM.

METHODS

From January 2011 to January 2017, 60 patients with CSM were prospectively enrolled in the present study. The patients were divided according to the modified Japanese Orthopaedic Association scale (mJOA) score into 2 groups: group A, patients with mild to moderate CSM (mJOA score ≥13); and group B, patients with severe myelopathy (mJOA score <13). Data were collected for each participating subject, including demographic information, symptoms, medical history, radiologic and neurophysiologic features, and functional impairment.

RESULTS

Of the 60 patients, 35 were men (58.3%) and 25 were women (41.7%). Their average age was 57.48 ± 10.60 years. The mean symptom duration was 25.33 ± 16.00 months; range, 3-57 months). Of the 60 patients, 22 had undergone single-level corpectomy and 36 multilevel corpectomy. A significant improvement in the motor evoked potentials was observed in both groups.

CONCLUSIONS

Single- and multilevel corpectomy are valid and safe options in the treatment of CSM. In the present prospective study, a statistically significant improvement in the mJOA score and neurophysiologic parameters was observed for both moderate and severe forms of CSM.

Open-Door Laminoplasty Using Lateral Mass Anchoring Screws and Nonabsorbable Sutures in Patients with Multilevel Cervical Myelopathy

Backgroud

The purpose of this study was to evaluate the clinical usefulness of open-door laminoplasty using lateral mass anchoring screws and nonabsorbable sutures (ODLLM) for multilevel cervical myelopathy.

Methods

We retrospectively studied 30 patients who underwent ODLLM. Clinical evaluations were performed using a visual analog scale (VAS), Japanese Orthopaedic Association (JOA) score, and Neck Disability Index (NDI) preoperatively, at 1 year postoperatively, and at the last follow-up. Radiographic evaluation was done using cervical spine radiographs to measure changes in the lordotic angle and range of motion (ROM) preoperatively, at 1 year postoperatively, and at the last follow-up and computed tomography at 1 year postoperatively to measure the opening angle and anteroposterior diameter of the spinal canal.

Results

Significant improvement in VAS, JOA, and NDI was seen overall at 1 year after operation. However, there was no significant difference between 1 year after operation and the last follow-up. There were no significant changes in the lordotic angle and neck ROM. The mean opening angle of the opened lamina was measured as 39.04°. The mean anteroposterior diameter was significantly increased from 7.51 ± 1.79 mm before surgery to 13.98 ± 1.80 mm at 1 year of operation. Complications such as laminar reclosure and screw loosening were not observed in all cases.

Conclusions

The ODLLM was technically easy to perform and showed good results comparable to those of conventional techniques. It can be suggested that ODLLM is an appropriate treatment option for multilevel cervical myelopathy.

Upright Balance Control in Individuals with Cervical Myelopathy Following Cervical Decompression Surgery: A Prospective Cohort Study

Patients with cervical myelopathy may manifest impairments in functional activities and balance control caused by compression of the spinal cord. The objective of the current study was to determine long-term changes in the upright balance control of patients with cervical myelopathy who had undergone cervical decompression surgery. This is a prospective cohort study from the preoperative phase to 3 months, 6 months, and 1 year postsurgery. Fifty-three patients with cervical myelopathy were recruited for the cervical myelopathy group and 22 age-matched healthy controls were recruited for the control group. Functional assessments including Japanese Orthopedic Association Cervical Myelopathy Evaluation Questionnaire-Lower Extremity Function (JOACMEQ-LEF) and 10-second step test; as well as balance assessments including postural sway (center-of-pressure: COP) were performed for both groups. The JOACMEQ-LEF (p = 0.036) scores of the myelopathy group improved postoperatively, and a significant decrease in COP variables of postural sway was observed. The upright posture was less stable in the myelopathy group than in the control group (p < 0.05) both before and after surgery. The effect size and standard response mean of the COP variables ranged from −0.49 to 0.03 at 3 months, 6 months, and 1 year postsurgery. The upright balance control had improved significantly 6 months after decompression surgery. However, the balance control of the patients who had undergone decompression surgery remained less stable than that of the age-matched healthy controls. Balance training should be initiated before 6 months postsurgery to accelerate balance control recovery in patients with cervical myelopathy.

Perturbation-Based Balance Training in Postoperative Individuals With Degenerative Cervical Myelopathy

Degenerative cervical myelopathy (DCM) is a common aging condition caused by spinal cord compression. Individuals with DCM often presented with residual balance and functional impairments postoperatively. Perturbation-based balance training (PBT) has been shown to have positive effects on populations with neurological disorders but has yet to be investigated in DCM. The objective of this study was therefore to evaluate the effects of PBT on balance and functional performance in postoperative individuals with DCM. Fifteen postoperative individuals with DCM (DCM group) and 14 healthy adults (healthy control group) were recruited. The DCM group received a 4-weeks PBT using a perturbation treadmill. The outcome measures included mean velocity of center of pressure (COP) during quiet standing; center of mass (COM) variance and reaction time to balance perturbation during standing with forward and backward perturbation; gait speed during level ground walking; Timed Up and Go Test (TUG) and disability questionnaire scores including Visual Analog Scale, Neck Disability Index, and Lower Extremity Function of Japanese Orthopaedic Association Cervical Myelopathy Evaluation Questionnaire. The assessments were conducted pre- and post-training postoperatively for the DCM group but only once for the healthy control group. Significant improvements were observed in the mean velocity of COP, COM variance, reaction time, gait speed, and TUG in the DCM group. Disability questionnaire scores were not significantly different after training in DCM group. For between-group comparisons, significant differences that were observed pre-training were not observed post-training. The 4-weeks PBT is a potential rehabilitation strategy for addressing balance and functional impairment in postoperative individuals with DCM. In addition, the post-training performance in the DCM group exhibited trends comparable to those of age-matched healthy controls. Furthermore, the training regimens offer a practical reference for future studies on populations with balance disorders. Future studies complemented with neurophysiological assessments could reveal more information of the underlying mechanisms of PBT.

Degenerative cervical myelopathy - update and future directions

Degenerative cervical myelopathy (DCM) is the leading cause of spinal cord dysfunction in adults worldwide. DCM encompasses various acquired (age-related) and congenital pathologies related to degeneration of the cervical spinal column, including hypertrophy and/or calcification of the ligaments, intervertebral discs and osseous tissues. These pathologies narrow the spinal canal, leading to chronic spinal cord compression and disability. Owing to the ageing population, rates of DCM are increasing. Expeditious diagnosis and treatment of DCM are needed to avoid permanent disability. Over the past 10 years, advances in basic science and in translational and clinical research have improved our understanding of the pathophysiology of DCM and helped delineate evidence-based practices for diagnosis and treatment. Surgical decompression is recommended for moderate and severe DCM; the best strategy for mild myelopathy remains unclear. Next-generation quantitative microstructural MRI and neurophysiological recordings promise to enable quantification of spinal cord tissue damage and help predict clinical outcomes. Here, we provide a comprehensive, evidence-based review of DCM, including its definition, epidemiology, pathophysiology, clinical presentation, diagnosis and differential diagnosis, and non-operative and operative management. With this Review, we aim to equip physicians across broad disciplines with the knowledge necessary to make a timely diagnosis of DCM, recognize the clinical features that influence management and identify when urgent surgical intervention is warranted.

Serum oxidative stress influences neurological recovery after surgery to treat acutely worsening symptoms of compression myelopathy: a cross-sectional human study

Background

Recent reports indicate that oxidative stress induced by reactive oxygen species is associated with the pathobiology of neurodegenerative disorders that involve neuronal cell apoptosis. Here we conducted a cross-sectional study to evaluate serum levels of oxidative stress in cervical compression myelopathy.

Methods

Thirty-six serum samples were collected preoperatively from patients treated for acutely worsening compression myelopathy (AM) and chronic compression myelopathy (CM). Serum levels of oxidative stress markers were evaluated by measuring derivatives of reactive oxygen metabolites (ROM), which reflect concentrations of hydroperoxides. ROM in healthy individuals range from 250 to 300 (U. CARR), whereas ROM >340–400 and > 400 define moderate and severe levels of oxidative stress, respectively. Difference of ROM by the cause of disorders whether cervical spondylotic myelopathy (CSM) or cervical ossification of longitudinal ligament (OPLL), correlations between ROM and patient age, body mass index (BMI), history of smoking, existence of diabetes were examined. Neurological evaluations according to Japanese Orthopaedic Association (JOA) scores were performed and correlated with ROM.

Results

ROM increased to 349.5 ± 54.8, representing a moderate oxidative stress, in CM samples. ROM increased to 409.2 ± 77.9 in AM samples, reflecting severe oxidative stress which were significantly higher than for CM samples (p < 0.05). There was no significant difference by the cause of disorders (CSM or OPLL). ROM were significantly increased in AM serum samples from female patients versus AM male and CM patients (p < 0.05). There were no correlations between ROM and age, BMI, history of smoking, and existence of diabetes. A negative correlation between ROM and recovery rate of JOA score (R² = 0.454, p = 0.047) was observed in the AM group.

Conclusions

Although moderate oxidative stress was present in patients with CM, levels of oxidative stress increased in severity in patients with AM. These results suggest that postsurgical neurological recovery is influenced by severe oxidative stress in AM.

Treatment of Mild Cervical Myelopathy: Factors Associated With Decision for Surgical Intervention

STUDY DESIGN

Prospective Cohort OBJECTIVE.: The aim of this study was to evaluate which demographic, clinical, or radiographic factors are associated with selection for surgical intervention in patients with mild cervical spondylotic myelopathy (CSM).

SUMMARY OF BACKGROUND DATA

Surgery has not been shown superior to best conservative management in mild CSM comparative studies; trials of conservative management represent an acceptable alternative to surgical decompression. It is unknown what patients benefit from surgery.

METHODS

This is a prospective study of patients with mild CSM, defined as modified Japanese Orthopaedic Association Score (mJOA) ≥15. Patients were recruited from seven sites contributing to the Canadian Spine Outcomes Research Network. Demographic, clinical, radiographic and health related quality of life data were collected on all patients at baseline. Multivariate logistic regression modeling was used to identify factors associated with surgical intervention.

RESULTS

There were 122 patients enrolled, 105 (86.0%) were treated surgically, and 17 (14.0%) were treated nonoperatively. Overall mean age was 54.8 years (SD 12.6) with 80 (65.5%) males. Bivariate analysis revealed no statistically significant differences between surgical and nonoperative groups with respect to age, sex, BMI, smoking status, number of comorbidities and duration of symptoms; mJOA scores were significantly higher in the nonoperative group (16.8 [SD 0.99] vs. 15.9 [SD 0.89], P < 0.001). There was a statistically significant difference in Neck Disability Index, SF12 Physical Component, SF12 Mental Component Score, EQ5D, and PHQ-9 scores between groups; those treated surgically had worse baseline questionnaire scores (P < 0.05). There was no difference in radiographic parameters between groups. Multivariable analysis revealed that lower quality of life scores on EQ5D were associated with selection for surgical management (P < 0.018).

CONCLUSION

Patients treated surgically for mild cervical myelopathy did not differ from those treated nonoperatively with respect to baseline demographic or radiographic parameters. Patients with worse EQ5D scores had higher odds of surgical intervention.

LEVEL OF EVIDENCE

3.

Recovery Process After Anterior Cervical Decompression in Patients With Cervical Spondylotic Myelopathy With Different Natural History

STUDY DESIGN

An observational prospective cohort study.

OBJECTIVE

To investigate the influence of natural history on the recovery of patients with cervical spondylotic myelopathy (CSM) after anterior cervical decompression.

SUMMARY OF BACKGROUND DATA

The natural history of CSM has not been clearly elucidated, it remains unclear whether the natural history of CSM is associated with the recovery process after surgical treatment.

MATERIALS AND METHODS

Patients with CSM (n=117) after anterior cervical decompression were stratified variously on the basis of natural history features. Baseline and postoperative neurological functions were rated using the Japanese Orthopaedic Association (JOA) and patient-based self-evaluation (PBSE) scores. The minimum and maximum recovery times for sensory function, and motor functions of the upper and lower extremities were analyzed separately at time points 1-60 months after surgery.

RESULTS

In all patients, the postoperative JOA and PBSE scores were significantly improved relative to baseline, in which sensory function recovered most quickly, followed by upper-extremity and lower-extremity motor functions. However, when compared with patients whose first symptom onset at the lower extremity, patients with the first onset at the upper extremity required less time to recover lower-extremity motor function, but more time to recover upper-extremity motor function. Patients with rapid progression had significantly lower preoperative and final JOA and PBSE scores compared with patients whose progression was steady or stepwise. Patients with preoperative symptoms ≥1 year had longer recovery time and poorer functional outcomes compared with those symptoms <1 year.

CONCLUSIONS

In patients with CSM, the location of first symptom onset, progressive velocity of symptom, and duration of preoperative symptoms significantly influenced the recovery process after anterior cervical decompression.

LEVEL OF EVIDENCE

Level 2-observational prospective study.

Anterior Surgical Techniques for Cervical Spondylotic Myelopathy: WFNS Spine Committee Recommendations

Objective

This study was performed to review the literature and to present the most up-to-date information and recommendations on the indications, complications, and success rate of anterior surgical techniques for cervical spondylotic myelopathy (CSM). The commonly performed anterior surgical procedures are multiple-level anterior cervical discectomy and fusion, anterior cervical corpectomy and fusion and its variants (skip corpectomy and hybrid surgery), and oblique corpectomy without fusion.

Methods

A comprehensive literature search and analysis were performed using MEDLINE (PubMed), the Cochrane Register of Controlled Trials, and the Web of Science for peer-reviewed articles published in English during the last 10 years.

Results

Corpectomy is mandated for ventral compression of fewer than 3 vertebral segments where single-level disc and osteophyte excision is inadequate to decompress the cord. Endoscopic or oblique partial corpectomy improves the sagittal canal diameter by 67% and obviates the need for an additional bone graft procedure.

Conclusion

The indications of anterior surgery in patients with CSM include a straightened or kyphotic spine with a compression level lower than 3. With an appropriate choice of implants and meticulous surgical technique, surgical complications can be seen only rarely. Improvements after anterior surgery for CSM have been reported in 70% to 80% of patients.

Cervical Myelopathy without Symptoms in the Upper Extremities: Incidence and Presenting Characteristics

BACKGROUND

Common signs and symptoms of cervical myelopathy (CM) predominantly manifest in the upper extremities and include hand numbness, hand clumsiness, and distal upper extremity weakness. CM manifesting without symptoms in the upper extremities is rare. This study aimed to better understand the incidence and character of such cases.

METHODS

A retrospective review of surgeries for CM from disc herniation, spondylosis, or ossification of posterior longitudinal ligament over a 12-year period was performed to identify patients presenting without symptoms in the upper extremities.

RESULTS

Of 982 surgically treated patients with CM, 12 (1.2%) had no upper extremity symptoms. All had difficulty ambulating, and 7 of 12 (58%) patients had objective lower extremity weakness. Ten (83%) patients had a history of lumbar degenerative disease. On sensory examination, 4 (33%) patients had a discernible midthoracic pin level, 3 (25%) had loss of sensation from the upper leg and genital area down, and 2 (17%) had only genital/upper thigh area sensory loss. All patients demonstrated neurologic improvement after decompressive surgery.

CONCLUSIONS

Patients with CM may rarely present without symptoms in the upper extremities, presenting with numbness perceived from the upper trunk, waist area, or perineum and legs in addition to leg weakness and gait difficulty. All patients had cervical cord compression at either C5-6 or C6-7 level, accounting for 1% of all patients undergoing cervical surgery. Awareness of this atypical pattern of presentation may aid in clinical assessment of a subset of patients with cervical cord compression.

The DOWN Questionnaire: A Novel Screening Tool for Cervical Spondylotic Myelopathy

STUDY DESIGN

Case-control study.

OBJECTIVES

Cervical spondylotic myelopathy (CSM) is the most common cause of spinal cord injury in adults aged over 55 years. However, since the onset is typically insidious, accurately diagnosing CSM can be challenging, often requiring referral to a subspecialist and advanced imaging. To help identify patients at risk for CSM, this case-control study compared responses to a series of 4 questions (DOWN questionnaire) in myelopathic and non-myelopathic patients.

METHODS

Ninety-two patients, 46 with and 46 without myelopathy, were recruited for the study. Each patient answered 4 questions encompassing common symptoms associated with CSM. Responses between patient groups were compared, and Cohen's κ was used to assess for agreement between responses and the diagnosis of myelopathy.

RESULTS

We found a sensitivity of 91% and a κ of 0.54 to 3 positive responses and a sensitivity of 72% and a κ of 0.61 to 4 positive responses.

CONCLUSIONS

Positive responses to 3 or more DOWN questions has high sensitivity and moderate agreement with the diagnosis of myelopathy based on history, physical exam, and review of advanced imaging by an orthopedic or neurological surgeon. The DOWN questionnaire is a potentially useful screening tool to identify patients at risk for CSM.

Consultation and Surgical Wait Times in Cervical Spondylotic Myelopathy

BACKGROUND

Cervical spondylotic myelopathy (CSM) is the leading cause of spinal cord impairment. In a public healthcare system, wait times to see spine specialists and eventually access surgical treatment for CSM can be substantial. The goals of this study were to determine consultation wait times (CWT) and surgical wait times (SWT), and identify predictors of wait time length.

METHODS

Consecutive patients enrolled in the Canadian Spine Outcomes and Research Network (CSORN) prospective and observational CSM study from March 2015 to July 2017 were included. A data-splitting technique was used to develop and internally validate multivariable models of potential predictors.

RESULTS

A CSORN query returned 264 CSM patients for CWT. The median was 46 days. There were 31% mild, 35% moderate, and 33% severe CSM. There was a statistically significant difference in median CWT between moderate and severe groups; 207 patients underwent surgical treatment. Median SWT was 42 days. There was a statistically significant difference in SWT between mild/moderate and severe groups. Short symptom duration, less pain, lower BMI, and lower physical component score of SF-12 were predictive of shorter CWT. Only baseline pain and medication duration were predictive of SWT. Both CWT and SWT were shorter compared to a concurrent cohort of lumbar stenosis patients (p &lt;0.001).

CONCLUSIONS

Patients with shorter duration (either symptoms or medication) and less neck pain waited less to see a spine specialist in Canada and to undergo surgical treatment. This study highlights some of the obstacles to overcome in expedited care for this patient population.

Surgical treatment of cervical spondylosis in patients 80 years of age and older-A retrospective observational study

The older adult population in developed countries is rapidly increasing, as is the number of older adults with cervical spondylosis. Previous studies on the surgical outcomes of older adults with cervical spondylosis have reported contradictory results. This study aimed to compare the surgical outcomes in adults with cervical spondylosis who were <80 and ≥80 years old. We retrospectively investigated data from adults who underwent surgical treatment for cervical spondylosis between 2006 and 2016. The clinical outcomes and postoperative complications of patients who were <80 years old were compared to those of patients who were ≥80 years old. Of the 108 patients included in the study, 14 (13.0%) were ≥80 years old. The preoperative neurosurgical cervical spine score was significantly different between patients who were <80 (9.1 ± 2.4) and ≥80 (6.1 ± 2.1) years old (p < .001). The recovery rate was 58.2 ± 30.0% and 41.3 ± 24.7% in patients who were <80 and ≥80 years old, respectively (p = .05). However, the number of recovery points scored was 2.8 ± 2.0 and 3.4 ± 2.3 in patients who were <80 and ≥80 years old, respectively, which was not significantly different. Although 12 patients had medical comorbidities, they had no surgical complications. This study clarifies the benefits of surgical treatment for older adults with cervical spondylosis. Generally, older adults have lower recovery rates and are unlikely to experience full recovery; however, surgery for cervical spondylosis appears to improve patients’ quality of life.

A Two-Year Cost Analysis of Maximum Nonoperative Treatments in Patients with Cervical Stenosis that Ultimately Required Surgery

OBJECTIVE

The aim of this study is to characterize the use and associated costs of maximal nonoperative therapy (MNT) received within 2-years before anterior cervical discectomy and fusion (ACDF) surgery in patients with symptomatic cervical stenosis.

METHODS

An insurance database, including private/commercially insured and Medicare Advantage beneficiaries, was queried for patients undergoing 1-level, 2-level, or 3-level ACDF procedures between 2007 and 2016. Research records were searchable by International Classification of Diseases diagnosis and procedure, Current Procedural Terminology, and generic drug codes. The use of MNTs within 2 years before index ACDF surgery was assessed by cost billed to patients, prescriptions written, and number of units billed.

RESULTS

Of 220,902 (7.16%) eligible patients, 15,825 underwent index surgery. Patient breakdown of the use of MNT modalities was as follows: 5731 (36.2%) used nonsteroidal antiinflammatory drugs; 9827 (62.1%) used opioids; 7383 (46.7%) used muscle relaxants; 3609 (22.8%) received cervical epidural steroid injection; 5504 (34.8%) attended physical therapy/occupational therapy; 1663 (10.5%) received chiropractor treatments; and 200 (1.3%) presented to the emergency department. During the 2-year preoperative period, there were 51,675 prescriptions for diagnostic cervical imaging. The total direct cost associated with all MNTs before ACDF was $16,056,556. Cervical spine imaging comprised the largest portion of the total MNT cost ($8,677,110; 54.0%), followed by cervical epidural steroid injection ($3,315,913; 20.7%) and opioids ($2,228,221; 13.9%). Opiates were the most frequently prescribed therapy (71,602 prescriptions).

DISCUSSION

Opioids are the most frequently prescribed and most used therapy in the preoperative period for cervical stenosis. Further studies and improved guidelines are necessary to determine which patients may benefit from ACDF earlier in the course of nonoperative therapies.

Cardiac Complications Related to Spine Surgery: Timing, Risk Factors, and Clinical Effect

INTRODUCTION

Large cohort studies evaluating cardiac complications in patients undergoing spine surgery are lacking. The purpose of this study was to determine the incidence, timing, risk factors, and effect of cardiac complications in spine surgery by using a national database, the American College of Surgeons National Surgical Quality Improvement Program.

METHODS

Patients who underwent spine surgery in the 2005 to 2012 National Surgical Quality Improvement Program database were identified. The primary outcome was an occurrence of cardiac arrest or myocardial infarction during the operation or the 30-day postoperative period. Risk factors for development of cardiac complications were identified using multivariate regression. The postoperative length of stay, 30-day readmission, and mortality were compared between patients who did and did not experience a cardiac complication.

RESULTS

A total of 30,339 patients who underwent spine surgery were identified. The incidence of cardiac complications was 0.34% (95% confidence interval [CI], 0.27% to 0.40%). Of the cases in which a cardiac complication developed, 30% were diagnosed after discharge. Risk factors for the development of cardiac complications were greater age (most notably ≥80 years, relative risk [RR] = 5.53; 95% CI = 2.28 to 13.43; P < 0.001), insulin-dependent diabetes (RR = 2.58; 95% CI = 1.51 to 4.41; P = 0.002), preoperative anemia (RR = 2.46; 95% CI = 1.62 to 3.76; P < 0.001), and history of cardiac disorders and treatments (RR = 1.88; 95% CI = 1.16 to 3.07; P = 0.011). Development of a cardiac complication before discharge was associated with a greater length of stay (7.9 versus 2.6 days; P < 0.001), and a cardiac complication after discharge was associated with increased 30-day readmission (RR = 12.32; 95% CI = 8.17 to 18.59; P < 0.001). Development of a cardiac complication any time during the operation or 30-day postoperative period was associated with increased mortality (RR = 113.83; 95% CI = 58.72 to 220.68; P < 0.001).

DISCUSSION

Perioperative cardiac complications were diagnosed in approximately 1 in 300 patients undergoing spine surgery. High-risk patients should be medically optimized and closely monitored through the perioperative period.

LEVEL OF EVIDENCE

Level III.