A systematic review of clinical and surgical predictors of complications following surgery for degenerative cervical myelopathy

Outcomes Following Two-Level Cervical Disc Arthroplasty Relative to Two-Level Anterior Cervical Discectomy

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

To evaluate postoperative adverse events, readmissions, and 5-year survival to reoperation for 2-level cervical disc arthroplasty (CDA) relative to 2-level anterior cervical discectomy and fusion (ACDF).

BACKGROUND

CDA and ACDF are both treatment options for degenerative cervical spine pathology. Relative to ACDF, CDA is a relatively novel treatment option, and limited research exists comparing outcomes between 2-level CDA and 2-level ACDF.

PATIENTS AND METHODS

Patients undergoing 2-level CDA or 2-level ACDF were isolated from the PearlDiver M165Ortho database. These 2 cohorts were matched 1:1 based on patient age, sex, and Elixhauser Comorbidity Index scores. The odds of 90-day postoperative adverse events were compared between the two groups by multivariable analysis. Overall cost-of-care for the first 90 days postoperatively and 5-year survival to cervical spine reoperation were then assessed.

RESULTS

Of the 2-level cases identified, only 3.9% had CDA, and the rest had ACDF. After matching, there were 4224 patients in each of the study groups. With controlling for patient age, sex, and Elixhauser Comorbidity Index on multivariable analysis, patients undergoing 2-level CDA had significantly lower odds of experiencing 90-day dysphagia [odds ratio (OR): 0.60, P < 0.0001 driving aggregated any adverse event (OR: 0.65, P < 0.0001)] and readmission (OR: 0.69, P = 0.0002). The median 90-day cost of care was greater for patients undergoing 2-level ACDF ($4776.00 vs . $3191.00, P < 0.0001). No significant difference in 5-year survival to cervical spine reoperation was identified ( P = 0.7).

CONCLUSIONS

Relative to patients undergoing 2-level ACDF, patients undergoing 2-level CDA were found to have significantly lower odds of 90-day readmissions and minor adverse events (dysphagia), while rates of major adverse events (pulmonary embolism, deep vein thrombosis, sepsis, etc .) were comparable between the groups. Further, patients undergoing CDA had lower cost of overall care, but no difference in 5-year survival to cervical spine reoperation. Thus, it may be appropriate to further consider CDA when 2-level surgery is pursued.

Mapping the Degenerative Cervical Myelopathy Research Landscape: Topic Modeling of the Literature

Study DesignTopic modeling of literature.ObjectivesOur study has 2 goals: (i) to clarify key themes in degenerative cervical myelopathy (DCM) research, and (ii) to evaluate the current trends in the popularity or decline of these topics. Additionally, we aim to highlight the potential of natural language processing (NLP) in facilitating research syntheses.MethodsDocuments were retrieved from Scopus, preprocessed, and modeled using BERTopic, an NLP-based topic modeling method. We specified a minimum topic size of 25 documents and 50 words per topic. After the models were trained, they generated a list of topics and corresponding representative documents. We utilized linear regression models to examine trends within the identified topics. In this context, topics exhibiting increasing linear slopes were categorized as "hot topics," while those with decreasing slopes were categorized as "cold topics".ResultsOur analysis retrieved 3510 documents that were classified into 21 different topics. The 3 most frequently occurring topics were "OPLL" (ossification of the posterior longitudinal ligament), "Anterior Fusion," and "Surgical Outcomes." Trend analysis revealed the hottest topics of the decade to be "Animal Models," "DCM in the Elderly," and "Posterior Decompression" while "Morphometric Analyses," "Questionnaires," and "MEP and SSEP" were identified as being the coldest topics.ConclusionsOur NLP methodology conducted a thorough and detailed analysis of DCM research, uncovering valuable insights into research trends that were otherwise difficult to discern using traditional techniques. The results provide valuable guidance for future research directions, policy considerations, and identification of emerging trends.

Pterional vs. mini-pterional craniotomy for intracranial aneurysms: a systematic review and meta-analysis

The mini-pterional craniotomy (mPT) was designed to be a minimally invasive alternative to the standard pterional (PT) approach. However, it remains unclear which technique produces better results. Thus, we aimed to perform a meta-analysis comparing functional, surgical, and aesthetic outcomes between mPT and PT in intracranial aneurysms. We searched PubMed, EMBASE, Web of Science, and Cochrane Library for studies comparing mPT to PT in patients who underwent clipping of brain aneurysms until June 2024. Outcomes were modified Rankin Scale (mRS) or Glasgow Outcome Scale (GOS), surgical complications, operation time, length of stay, and patients' aesthetic satisfaction. Statistical analysis was performed using the R software (version 4.4.0). Heterogeneity was assessed with I2 statistics. We included 6 studies with a total of 1011 patients, of whom 696 (63.1%) underwent mPT. The mean age was 59.0 ± 2.8 years, 67.6% were female, and 68.2% of all aneurysms were located in the middle cerebral artery. Unfavorable functional outcome (mRS ≥ 3 or GOS ≤ 3) at discharge (OR 0.21, 95% CI: 0.07-0.59; I2 = 0%), overall surgical complications (OR 0.45, 95% CI: 0.21-0.99; I2 = 72%), and operation time (MD - 54.42 min, 95% CI: -60.78 to - 48.06; I2 = 0%) were significantly lower in mPT compared to PT. Moreover, patients' aesthetic satisfaction was statistically higher in mPT (OR 2.91, 95% CI: 1.06-8.00; I2 = 0%). However, there was no significant difference in length of stay between groups (MD - 1.52 days, 95% CI: -3.75 to 0.72; I2 = 72%). Mini-pterional craniotomy is associated with better functional outcomes at discharge, fewer surgical complications, and a shorter operation time. Therefore, our results might suggest that mPT is a promising and preferable alternative to standard PT.

Imaging Characteristics of Nonrheumatoid Arthritis Patients With Retro-odontoid Pseudotumor: A Multicenter Case-control Study

STUDY DESIGN

Multicenter case-control study.

OBJECTIVE

To identify imaging characteristics of the cervical spine in patients with retro-odontoid pseudotumor (ROP) without rheumatoid arthritis (RA) and determine the pathogenesis of ROP.

BACKGROUND

ROP results from proliferative changes in the soft tissue of the atlantoaxial junction surrounding the region of the transverse ligament, and is commonly seen in RA patients. However, the pathogenesis of ROP caused by mechanical instability of the upper cervical spine in patients without RA is yet to be explained.

MATERIALS AND METHODS

We collected imaging data [preoperative radiographs, magnetic resonance imaging (MRI), and computed tomography (CT)] of patients who underwent surgery between April 2011 and March 2022 at the three university hospitals for ROP (cases) and cervical spondylotic myelopathy (as age, sex, and institution matched controls). The two groups were compared for different parameters on cervical dynamic radiographs, MRI, and CT.

RESULTS

The ROP group consisted of 42 patients, and the control group comprised 168 patients. C2-C7 range of motion was significantly smaller in the ROP group (25.8 ± 2.6°) compared with the control group (33.0 ± 1.0°). C2-C7 sagittal vertical axis was significantly larger in the ROP group than the control group (39.3 ± 3.6 vs. 32.2 ± 1.3 mm). MRI and CT assessment showed progressive degeneration at all intervertebral levels in the ROP group. A significant positive correlation was observed between the thickness of the soft tissue posterior to the dental process and the atlantodental interval in the flexion position ( r = 0.501).

CONCLUSIONS

The development of ROP was associated with degeneration of facet joints and intervertebral disks in the middle and lower cervical spine. Our findings suggest that decreased mobility of the middle and lower cervical spine may cause instability in the upper cervical spine, leading to the formation of ROP.

Complications and Reoperation Following Surgery for Concurrent Carpal Tunnel and Cervical Spine Compression

BACKGROUND

Patients with carpal tunnel syndrome (CTS) may also have cervical radiculopathy (CR) or vice versa, potentially requiring carpal tunnel release (CTR) and anterior cervical discectomy and fusion (ACDF). This study evaluates whether there is an increased risk of complications following CTR or ACDF in patients with concurrent CTS and CR (CTS-CR) compared with those with only CTS or CR.

METHODS

A multipayer database was used to identify patients with CTS-CR. From this cohort, patients who underwent CTR and/or ACDF were identified. Patients with CTS-CR undergoing surgery were compared with those undergoing surgery with only CTS or CR. Multivariable logistic regression was used to compare matched populations to assess postoperative complications and risk of undergoing both procedures.

RESULTS

A total of 110 379 patients with CTS-CR were identified. Carpal tunnel release was performed in 21 152 patients (19.2%) with CTS-CR, from which 835 (0.76%) underwent ACDF. Anterior cervical discectomy and fusion was performed in 6960 patients (6.31%) with CTS-CR followed by CTR in 1098 patients (0.99%). Patients with CTS-CR were at greater risk of reoperation and complex regional pain syndrome following CTR. In ACDF, patients with CTS-CR were at greater risk of reoperation. Obesity and tobacco use were significant risk factors in patients with CTS-CR who underwent both CTR and ACDF rather than a single surgery.

CONCLUSIONS

Examination of more than 100 000 patients with CTS-CR found a greater likelihood of reoperation and perioperative complications following surgery than those without concurrent diagnoses. Obesity and smoking increased the risk for patients undergoing both procedures. Patients presenting with CTS-CR are high risk and should be counseled on risk of complication and reoperation and optimized to reduce risk of undergoing both CTR and ACDF.

Advanced MRI metrics improve the prediction of baseline disease severity for individuals with degenerative cervical myelopathy

BACKGROUND CONTEXT

Degenerative cervical myelopathy (DCM) is the most common form of atraumatic spinal cord injury globally. Degeneration of spinal discs, bony osteophyte growth and ligament pathology results in physical compression of the spinal cord contributing to damage of white matter tracts and grey matter cellular populations. This results in an insidious neurological and functional decline in patients which can lead to paralysis. Magnetic resonance imaging (MRI) confirms the diagnosis of DCM and is a prerequisite to surgical intervention, the only known treatment for this disorder. Unfortunately, there is a weak correlation between features of current commonly acquired MRI scans ("community MRI, cMRI") and the degree of disability experienced by a patient.

PURPOSE

This study examines the predictive ability of current MRI sequences relative to "advanced MRI" (aMRI) metrics designed to detect evidence of spinal cord injury secondary to degenerative myelopathy. We hypothesize that the utilization of higher fidelity aMRI scans will increase the effectiveness of machine learning models predicting DCM severity and may ultimately lead to a more efficient protocol for identifying patients in need of surgical intervention.

STUDY DESIGN/SETTING

Single institution analysis of imaging registry of patients with DCM.

PATIENT SAMPLE

A total of 296 patients in the cMRI group and 228 patients in the aMRI group.

OUTCOME MEASURES

Physiologic measures: accuracy of machine learning algorithms to detect severity of DCM assessed clinically based on the modified Japanese Orthopedic Association (mJOA) scale.

METHODS

Patients enrolled in the Canadian Spine Outcomes Research Network registry with DCM were screened and 296 cervical spine MRIs acquired in cMRI were compared with 228 aMRI acquisitions. aMRI acquisitions consisted of diffusion tensor imaging, magnetization transfer, T2-weighted, and T2*-weighted images. The cMRI group consisted of only T2-weighted MRI scans. Various machine learning models were applied to both MRI groups to assess accuracy of prediction of baseline disease severity assessed clinically using the mJOA scale for cervical myelopathy.

RESULTS

Through the utilization of Random Forest Classifiers, disease severity was predicted with 41.8% accuracy in cMRI scans and 73.3% in the aMRI scans. Across different predictive model variations tested, the aMRI scans consistently produced higher prediction accuracies compared to the cMRI counterparts.

CONCLUSIONS

aMRI metrics perform better in machine learning models at predicting disease severity of patients with DCM. Continued work is needed to refine these models and address DCM severity class imbalance concerns, ultimately improving model confidence for clinical implementation.

Untwining the intertwined: a comprehensive review on differentiating pathologies of the shoulder and spine

Background

The anatomic interplay and overlap between the cervical spine and the shoulder constitutes a challenge for shoulder and spine surgeons, as symptoms of spine and shoulder pathologies are often similar and may lead to entity misdiagnosis.

Methods

PubMed, Cochrane, and Google Scholar (page 1-20) searches were updated to October 2023 in search of the qualified papers. Boolean Operators were used with a combination of the keywords "spine" OR "neck" And "Shoulder". Furthermore, reference lists from papers were also searched to find literature.

Results

It is of pivotal importance to conduct comprehensive preoperative clinical investigation to appropriately evaluate and assess the source of the pathology and the leading causes behind it. Certain markers can help guide surgeons towards etiologies, and these include areas of pain and physical exam findings with the arm squeeze test having the highest sensitivity and specificity for diagnosing cervical radiculopathy. As for the shoulder, despite its low sensitivity, the Yergason test had the highest specificity for diagnosing subacromial impingement. Local anesthetic injection can help as well in the diagnostic approach. Moreover, the interplay between these anatomic locations is not solely related to preoperative diagnosis. Studies have shown that previous surgery for cervical spine pathology may negatively affect the outcomes of shoulder procedures like arthroplasties.

Conclusion

Shoulder and spine surgeons should be wary and vigilant of accurately diagnosing the etiology of the presenting symptoms to ensure proper management and optimize prognosis.

A Comparison of Short-Term Outcomes after Surgical Treatment of Multilevel Degenerative Cervical Myelopathy in the Geriatric Patient Population: An Analysis of the National Surgical Quality Improvement Program Database 2010-2020

STUDY DESIGN

Retrospective review of the American College of Surgeons-National Surgical Quality Improvement Program database from 2010 to 2020.

PURPOSE

To compare the short-term complication rates of anterior cervical decompression and fusion (ACDF), posterior cervical laminoplasty (LP), and posterior cervical laminectomy and fusion (PCF) in a geriatric population.

OVERVIEW OF LITERATURE

The geriatric population in the United States has increased significantly. Degenerative cervical myelopathy (DCM) is caused by cervical spinal stenosis, and its prevalence increases with age. Therefore, the incidence of multilevel DCM requiring surgical intervention is likely to increase. ACDF, LP, and PCF are the most commonly used surgical techniques for treating multilevel DCM. However, there is uncertainty regarding the optimal surgical technique for the decompression of DCM in geriatric patients.

METHODS

Patients aged 65 years who had undergone either multilevel ACDF, LP, or PCF for the treatment of DCM were analyzed. Additional analysis was performed by standardizing the data for the American Society of Anesthesiologists classification scores and preoperative functional status.

RESULTS

A total of 23,129 patients were identified. Patients with ACDF were younger, more often female, and preoperatively healthier than those in the other two groups. The estimated postoperative mortality and morbidity, mean operation time, and length of hospital stay were the lowest for ACDF, second lowest for LP, and highest for PCF. The readmission and reoperation rates were comparable between ACDF and LP; however, both were significantly lower than PCF.

CONCLUSIONS

PCF is associated with the highest risk of mortality, morbidity, unplanned reoperation, and unplanned readmission in the short-term postoperative period in patients aged 65 years. In contrast, ACDF carries the lowest risk. However, some disease-specific factors may require posterior treatment. For these cases, LP should be included in the preoperative discussion when determining the ideal surgical approach for geriatric patients.

Elderly Patients Show Substantial Improvement in Health-Related Quality of Life After Surgery for Degenerative Cervical Myelopathy Despite Medical Frailty: An Ambispective Analysis of a Multicenter, International Data Set

BACKGROUND AND OBJECTIVES

We assessed the relationship between Modified Frailty Index-5 (mFI-5) and neurological outcomes, as well as health-related quality of life (HRQoL) measures, in elderly patients with degenerative cervical myelopathy (DCM) after surgery.

METHODS

Data from 3 major DCM trials (the Arbeitsgemeinschaft für Osteosynthesefragen Spine Cervical Spondylotic Myelopathy-North America, Cervical Spondylotic Myelopathy-International, and CSM-PROTECT studies) were combined, involving 1047 subjects with moderate to severe myelopathy. Patients older than 60 years with 6-month and 1-year postoperative data were analyzed. Neurological outcome was assessed using the modified Japanese Orthopaedic Association score, while HRQoL was measured using the 36-Item Short Form Health Survey (SF-36) (both Physical Component Summary [SF-36 PCS] and Mental Component Summary [SF-36 MCS] scores) and the Neck Disability Index. Frail (mFI ≥2) and nonfrail (mFI = 0-1) cohorts were compared using univariate paired statistics.

RESULTS

The final analysis included 261 patients (62.5% male), with a mean age of 71 years (95% CI 70.7-72). Frail patients (mFI ≥2) had lower baseline modified Japanese Orthopaedic Association scores (10.45 vs 11.96, P < .001), SF-36 PCS scores (32.01 vs 36.51, P < .001), and SF-36 MCS scores (39.32 vs 45.24, P < .001). At 6-month follow-up, SF-36 MCS improved by a mean (SD) of 7.19 (12.89) points in frail vs 2.91 (11.11) points in the nonfrail group (P = .016). At 1 year after surgery, frail patients showed greater improvement in both SF-36 PCS and SF-36 MCS composite scores compared with nonfrail patients (7.81 vs 4.49, P = .038, and 7.93 vs 3.01, P = .007, respectively). Bivariate regression analysis revealed that higher mFI-5 scores correlated with more substantial improvement in overall mental status at 6 months and 1 year (P = .024 and P = .009, respectively).

CONCLUSION

mFI-5 is a clinically helpful signature to reflect the HRQoL status among elderly patients with DCM. Despite preoperative medical frailty, elderly patients with DCM experience significant HRQoL improvement after surgery. These findings enable clinicians to identify elderly patients with modifiable comorbidities and provide informed counseling on anticipated outcomes.

LEVEL OF EVIDENCE

II.

Diagnostic and prognostic significance of preoperative evoked potential tests in degenerative cervical myelopathy

BACKGROUND CONTEXT

Decompression surgery is a treatment option for patients with degenerative cervical myelopathy (DCM). Surgical decisions primarily depend on clinical symptoms and radiological examinations. The diagnostic and prognostic significance of evoked potential tests for surgical outcomes in patients with DCM has not been thoroughly examined.

PURPOSE

To identify the diagnostic and prognostic significance of preoperative evoked potential tests in patients with DCM who underwent decompression surgery.

STUDY DESIGN

This was a retrospective observational study.

PATIENT SAMPLE

One hundred two consecutive patients who underwent evoked potential tests and surgical treatment between January 2016 and December 2020 in a single spine center and had a minimum follow-up of 6 months.

OUTCOME MEASURES

Japanese Orthopedic Association (JOA) scores obtained preoperatively and 6 months after surgery.

METHODS

This study evaluated the preoperative central motor conduction time (CMCT), somatosensory evoked potentials, and Japanese Orthopedic Association (JOA) scores obtained preoperatively and 6 months after surgery.

RESULTS

Abnormal CMCT findings were observed in 94 patients (92.2%). Abnormal somatosensory evoked potentials were observed in 77 patients (75.5%). There was a statistically significant correlation between preoperative JOA score and abductor pollicis brevis (APB)-CMCT (r=-0.546, p=.001), tibialis anterior (TA)-CMCT (r=-0.517, p<.001), median nerve (MN)-SSEP (r=-0.353, p=.001), and tibial nerve (TN)-SSEP (r=-0.349, p=.003). There were significant differences in recovery rates associated with diabetes mellitus (DM), preoperative severity of myelopathy, TA-CMCT, MN-SSEP, and TN-SSEP. Stepwise multiple regression analysis showed that the major factors affecting the clinical outcomes were TN-SSEP (β=0.327, p=.004), preoperative JOA score (β=0.278, p=.012), and DM (β=0.241, p=.025).

CONCLUSIONS

Evoked potential testing is a functional diagnostic tool that can indicate the severity of myelopathic symptoms in patients with DCM. Additionally, preoperative TN-SSEP may have significant prognostic value in predicting postoperative clinical outcomes. Thus, preoperative evoked potential tests could be helpful for determining suitable surgical treatment candidates and forecasting postoperative prognosis.

Degenerative Cervical Myelopathy: An Overview

Degenerative cervical myelopathy (DCM) is a spinal condition of growing importance due to its increasing prevalence within the ageing population. DCM involves the degeneration of the cervical spine due to various processes such as disc ageing, osteophyte formation, ligament hypertrophy or ossification, as well as coexisting congenital anomalies. This article provides an overview of the literature on DCM and considers areas of focus for future research. A patient with DCM can present with a variety of symptoms ranging from mild hand paraesthesia and loss of dexterity to a more severe presentation of gait disturbance and loss of bowel/bladder control. Hoffman's sign and the inverted brachioradialis reflex are also important signs of this disease. The gold standard imaging modality is MRI which can identify signs of degeneration of the cervical spine. Other modalities include dynamic MRI, myelography, and diffusion tensor imaging. One important scoring system to aid with the diagnosis and categorisation of the severity of DCM is the modified Japanese Orthopaedic Association score. This considers motor, sensory, and bowel/bladder dysfunction, and categorises patients into mild, moderate, or severe DCM. DCM is primarily treated with surgery as this can halt disease progression and may even allow for neurological recovery. The surgical approach will depend on the location of degeneration, the number of cervical levels involved and the pathophysiological process. Surgical approach options include anterior cervical discectomy and fusion, corpectomy, or posterior approach (laminectomy ± fusion). Conservative management is also considered for some patients with mild or non-progressive DCM or for patients where surgery is not an option. Conservative treatment may include physical therapy, traction, or neck immobilisation. Future recommendations include research into the prevalence rate of DCM and if there is a difference between populations. Further research on the benefit of conservative management for patients with mild or non-progressive DCM would be recommended.

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.

Effect of vitamin D deficiency on surgical outcomes of degenerative cervical myelopathy

Background

Due to its association with bone metabolic status and muscle strength/mass, vitamin D deficiency has the potential to affect neurological symptom recovery after surgery for degenerative cervical myelopathy (DCM). However, few studies have investigated the effects of vitamin D deficiency (serum 25(OH)D <20 ng/mL) on surgical outcomes in DCM patients. Herein, we investigated the prevalence of vitamin D deficiency in patients with DCM, and determined whether vitamin D deficiency affects surgical outcomes for DCM.

Methods

In this retrospective observational study we assessed the recovery rate 1 year after surgery in 91 patients diagnosed with DCM who underwent surgery. First, we analyzed the correlation between vitamin D levels and various background factors. Then, patients were divided into 2 groups according to vitamin D sufficiency, and univariate analysis was performed on vitamin D and surgical outcomes. Finally, Spearman correlation analyses were performed to identify factors correlated with recovery rate after surgery for DCM.

Results

The average Japanese Orthopedic Association score for the assessment of cervical myelopathy (C-JOA score) improved postoperatively. Age was positively correlated with vitamin D levels, and parathyroid hormone levels were negatively correlated with vitamin D levels. Among the 91 patients, 79.1% of patients were diagnosed with vitamin D deficiency. No significant differences in recovery rate were found between the vitamin D-deficient and vitamin D-sufficient groups. Finally, the Spearman correlation analysis showed a positive correlation between the preoperative C-JOA motor dysfunction score in the lower extremities and the recovery rate, while age demonstrated a negative correlation with recovery rate.

Conclusions

No association was found between vitamin D deficiency and clinical outcomes after surgery for DCM. The results of this study do not support the need to normalize vitamin D levels for achieving neurological improvements in patients with DCM.

Development of a validated search filter for Ovid Embase for degenerative cervical myelopathy

BACKGROUND

Degenerative cervical myelopathy (DCM) is a recently proposed umbrella term for symptomatic cervical spinal cord compression secondary to degeneration of the spine. Currently literature searching for DCM is challenged by the inconsistent uptake of the term 'DCM' with many overlapping keywords and numerous synonyms.

OBJECTIVES

Here, we adapt our previous Ovid medline search filter for the Ovid embase database, to support comprehensive literature searching. Both embase and medline are recommended as a minimum for systematic reviews.

METHODS

References contained within embase identified in our prior study formed a 'development gold standard' reference database (N = 220). The search filter was adapted for embase and checked against the reference database. The filter was then validated against the 'validation gold standard'.

RESULTS

A direct translation was not possible, as medline indexing for DCM and the keywords search field were not available in embase. We also used the 'focus' function to improve precision. The resulting search filter has 100% sensitivity in testing.

DISCUSSION AND CONCLUSION

We have developed a validated search filter capable of retrieving DCM references in embase with high sensitivity. In the absence of consistent terminology and indexing, this will support more efficient and robust evidence synthesis in the field.

Nationwide sample data analysis of additional surgery rate after anterior or posterior cervical spinal surgery

Surgical outcomes of degenerative cervical spinal disease are dependent on the selection of surgical techniques. Although a standardized decision cannot be made in an actual clinical setting, continued education is provided to standardize the medical practice among surgeons. Therefore, it is necessary to supervise and regularly update overall surgical outcomes. This study aimed to compare the rate of additional surgery between anterior and posterior surgeries for degenerative cervical spinal disease using the National Health Insurance Service-National Sample Cohort (NHIS-NSC) nationwide patient database. The NHIS-NSC is a population-based cohort with about a million participants. This retrospective cohort study included 741 adult patients (> 18 years) who underwent their first cervical spinal surgery for degenerative cervical spinal disease. The median follow-up period was 7.3 years. An event was defined as the registration of any type of cervical spinal surgery during the follow-up period. Event-free survival analysis was used for outcome analysis, and the following factors were used as covariates for adjustment: location of disease, sex, age, type of insurance, disability, type of hospital, Charles comorbidity Index, and osteoporosis. Anterior cervical surgery was selected for 75.0% of the patients, and posterior cervical surgery for the remaining 25.0%. Cervical radiculopathy due to foraminal stenosis, hard disc, or soft disc was the primary diagnosis in 78.0% of the patients, and central spinal stenosis was the primary diagnosis in 22.0% of them. Additional surgery was performed for 5.0% of the patients after anterior cervical surgery and 6.5% of the patients after posterior cervical surgery (adjusted subhazard ratio, 0.83; 95% confidence interval, 0.40-1.74). The rates of additional surgery were not different between anterior and posterior cervical surgeries. The results would be helpful in evaluating current practice as a whole and adjusting the health insurance policy.

Zonisamide improves Fas/FasL-mediated apoptosis and inflammation in a degenerative cervical myelopathy rat model

Degenerative cervical myelopathy (DCM) is a severe condition of the spinal cord caused by chronic compression. However, no studies to date have examined the effects of zonisamide (ZNS) on DCM via the Fas/FasL-mediated pathway. The aim of this study was to investigate the effects of ZNS on a DCM rat model and to explore the potential mechanisms. First, 40 adult Sprague-Dawley rats were used to establish the DCM rat model and were individually divided into four groups: the Sham group, DCM model group (DCM), ZNS group (DCM model rats treated with ZNS, 30 mg/kg/day), and ZNS + CD95 group (DCM model rats treated with ZNS and CD95). Histopathology injury and cell apoptosis, Fas and Fas ligand (FasL) expression and Fas/FasL relative protein levels were detected by hematoxylin and eosin staining, TUNEL assay, and immunofluorescence and western blotting, respectively. The results of our study demonstrated that ZNS could promote motor recovery while reversing histopathological injury and cell apoptosis in DCM rats. Moreover, Iba-1, Fas and FasL expression in DCM rats was decreased, accompanied by a decrease in cleaved caspase-3/caspase-3, cleaved caspase-8/caspase-8, cleaved caspase-9/caspase-9, cleaved caspase-10/caspase-10 and B-cell lymphoma-2 (Bcl-2)/Bcl-2 associated X (Bax) levels. All these results revealed that ZNS attenuates DCM injury in a rat model via the regulation of Fas and FasL signaling. Our study indicated that ZNS had beneficial effects on DCM and thus provided a novel theoretical approach for subsequent academic and clinical research on DCM injury.

Life expectancy in patients with degenerative cervical myelopathy is currently reduced but can be restored with timely treatment

PURPOSE

Degenerative cervical myelopathy is a progressive slow-motion spinal cord injury. Surgery is the mainstay of treatment. Baseline disability predicts surgical recovery; therefore, timely treatment is critical to restoring function. However, current challenges mean most patients present with advanced disease and are instead left with life changing disabilities. While short-term mortality is rarely reported, the long-term effects of this on life expectancy are unknown, including whether function could be modifiable with timely treatment. This article investigates the effect of DCM on life expectancy.

METHODS

The survival of patients from an observational study of patients undergoing surgery from 1994 to 2007 was compared to their expected survival using a gender- and aged -matched cohort. Comparisons were made by one sample log-rank test and standardised mortality ratios. Factors associated with survival were explored using a Cox regression analysis, including disease severity.

RESULTS

A total of 357 patients were included in the analysis. After a median follow-up of 15.3 years, 135 of 349 patients had died; 114.7 deaths would have been expected. The DCM cohort had an increased risk of death compared to the non-DCM cohort (standardised mortality ratio 1.18 [95% CI: 1.02-1.34]. Age at operation 1.08 (95% CI: 1.07 to 1.1, p < 0.001) and severe DCM 1.6 (95% CI: 1.06 to 2.3, p = 0.02) were associated with worse survival (N = 287). In those surviving at least 2 years after surgery, only severe DCM was associated with conditional survival (HR 1.6, 95% CI 1.04 2.4, p = 0.03).

CONCLUSION

Life expectancy is reduced in those undergoing surgery for DCM. This is driven by premature mortality among those left with severe disability. As disability can be reduced with timely treatment, these findings reinforce the need for collective and global action to raise awareness of DCM and enable early diagnosis.

Comparative Analysis of 30-Day Readmission, Reoperation, and Morbidity between Posterior Cervical Decompression and Fusion Performed in Inpatient and Outpatient Settings

STUDY DESIGN

A retrospective cohort study.

PURPOSE

To compare 30-day readmission, reoperation, and morbidity for patients undergoing posterior cervical decompression and fusion (PCDF) in inpatient vs. outpatient settings.

OVERVIEW OF LITERATURE

PCDF has recently been increasingly performed in outpatient settings, often utilizing minimally invasive techniques. However, literature evaluating short-term outcomes for PCDF is scarce. Moreover, no currently large-scale database studies have compared short-term outcomes between PCDF performed in the inpatient and outpatient settings.

METHODS

Patients who underwent PCDF from 2005 to 2018 were identified using the National Surgical Quality Improvement Program database. Regression analysis was utilized to compare primary outcomes between surgical settings and evaluate for predictors thereof.

RESULTS

We identified 8,912 patients. Unadjusted analysis revealed that outpatients had lower readmission (4.7% vs. 8.8%, p =0.020), reoperation (1.7% vs. 3.8%, p =0.038), and morbidity (4.5% vs. 11.2%, p <0.001) rates. After adjusting for baseline differences, readmission, reoperation, and morbidity no longer statistically differed between surgical settings. Outpatients had lower operative time (126 minutes vs. 179 minutes) and levels fused (1.8 vs. 2.2) (p <0.001). Multivariate analysis revealed that age (p =0.008; odds ratio [OR], 1.012), weight loss (p =0.045; OR, 2.444), and increased creatinine (p <0.001; OR, 2.233) independently predicted readmission. The American Society of Anesthesiologists (ASA) classification of ≥3 predicted reoperation (p =0.028; OR, 1.406). Rehabilitation discharge (p <0.001; OR, 1.412), ASA-class of ≥3 (p =0.008; OR, 1.296), decreased hematocrit (p <0.001; OR, 1.700), and operative time (p <0.001; OR, 1.005) predicted morbidity.

CONCLUSIONS

The 30-day outcomes were statistically similar between surgical settings, indicating that PCDF can be safely performed as an outpatient procedure. Surrogates for poor health predicted negative outcomes. These results are particularly important as we continue to shift spinal surgery to outpatient centers. This importance has been highlighted by the need to unburden inpatient sites, particularly during public health emergencies, such as the coronavirus disease 2019 pandemic.

Clinically meaningful improvement in disabilities of arm, shoulder, and hand (DASH) following cervical spine surgery

BACKGROUND CONTEXT

Patients with cervical spine disease suffer from upper limb disability. At present, no clinical benchmarks exist for clinically meaningful change in the upper limb function following cervical spine surgery.

PURPOSE

Primary: to establish clinically meaningful metrics; the minimal clinically important difference (MCID) and substantial clinical benefit (SCB) of upper limb functional improvement in patients following cervical spine surgery. Secondary: to identify the prognostic factors of MCID and SCB of upper limb function following cervical spine surgery.

STUDY DESIGN

Retrospective cohort study.

PATIENT SAMPLE

Adult patients ≥18 years of age who underwent cervical spine surgery from 2012 to 2016.

OUTCOME MEASURES

Patient-reported outcomes: Neck disability index (NDI) and Disabilities of Arm, Shoulder, and Hand (DASH).

METHODS

MCID was defined as minimal improvement and SCB as substantial improvement in the DASH score at last follow-up. The anchor-based methods (ROC analyses) defined optimal MCID and SCB thresholds with area under curve (AUC) in discriminating improved vs. non-improved patients. The MCID was also calculated by distribution-based methods: half standard-deviation (0.5-SD) and standard error of the mean (SEM) method. A multivariable logistic regression evaluated the impact of baseline factors in achieving the MCID and SCB in DASH following cervical spine surgery.

RESULTS

Between 2012 and 2016, 1,046 patients with average age of 57±11.3 years, 53% males, underwent cervical spine surgery. Using the ROC analysis, the threshold for MCID was -8 points with AUC of 0.73 (95% CI: 0.67-0.79) and the SCB was -18 points with AUC of 0.88 (95% confidence interval [CI]: 0.85-0.91). The MCID was -11 points by 0.5-SD and -12 points by SEM-method. On multivariable analysis, patients with myelopathy had lower odds of achieving MCID and SCB, whereas older patients and those with ≥6 months duration of symptoms had lower odds of achieving DASH MCID and SCB respectively.

CONCLUSIONS

In patients undergoing cervical spine surgery, MCID of -8 points and SCB of -18 points in DASH improvement may be considered clinically significant. These metrics may enable evaluation of minimal and substantial improvement in the upper extremity function following cervical spine surgery.

The application of three-dimensional printed patient-specific drilling templates for expansive open-door laminoplasty: A single-center, prospective randomized controlled study

Background

The choice of trough position in Expansive open-door laminoplasty (EOLP) mostly relied on bony landmarks and surgeons' experience. The present study was to validate the efficacy of the three-dimensional (3D) printed patient-specific drilling templates with the function of locating and depth control for EOLP.

Materials and Methods

A single-center, prospective randomized controlled study was conducted on the patients who underwent unilateral EOLP from August 2019 to December 2020. The 3D printed patient-specific drilling template was fabricated and used in the template group. All the EOLP were performed by a senior surgeon and a junior surgeon. The clinical outcomes and radiographic results were evaluated.

Results

A total of 37 patients who completed the 12-month follow-up were analyzed. The clinical outcomes were significantly improved after surgery in both groups (P < 0.05). The visual analogue scale (VAS) scores were significantly lower in the template group at 12 months postoperatively (P < 0.05). The anteroposterior diameter, Pavlov's ratio and Open angle were all higher in the template group than those in the control group at 3 days and 12 months postoperatively (P < 0.05). The satisfaction of the trough position on both sides and incomplete fracture rate on the hinge side were higher in the template group based on the CT scans taken 3 days after surgery (P < 0.05). To the junior surgeon, the satisfaction and the incomplete fracture rate were significantly higher in the template group compared with those in the control group (P < 0.05).

Conclusion

The application of 3D printed patient-specific drilling templates with the function of locating and depth control for EOLP could improve the outcome of neck pain relief and expand the decompression. It can also improve the satisfaction of the trough position on the open-door side and the hinge side and decrease the complete fracture rate on the hinge side, especially for the junior surgeon.

Comparison of clinical efficacy between retention and removal of the vertebral bony endplate in anterior cervical discectomy and fusion for the treatment of cervical spondylotic myelopathy

BACKGROUND

Anterior cervical discectomy and fusion (ACDF) have a history of more than 60 years to treat cervical spondylotic myelopathy. This study is based on the original classic surgical procedure to remove the bony endplate to expand the range of vertical decompression to analyze and compare the clinical efficacy of two different ACDF in treating cervical spondylotic myelopathy.

METHODS

The inpatients in hospital were randomly divided into two groups A and B. Patients in Group A received ACDF surgery with bony endplates preserved, and patients in group B received ACDF surgery with bony endplates removed. All patients were followed-up for three years, and then compared the clinical efficacy from the following aspects, blood loss statistics during and after the operation, Japanese Orthopedic Association's scoring (JOA) standard for cervical spondylotic myelopathy, Cervical curvature index, cervical flexion and extension range, intervertebral bone graft fusion time and fusion rate.

RESULTS

1. The operative time and intraoperative (postoperative) blood loss in group A were significantly better than that in group B, with statistical significance (P < 0.05)0.2. There was no significant difference in postoperative neurological function recovery, cervical curvature index, cervical flexion and extension activity, and Intervertebral fusion time between two groups (P > 0.05), while group A was superior to group B in terms of bone graft fusion rate (P < 0.05). 3. Four patients (6.7%) in group B suffered from dyspnea due to neck hematoma caused by drainage tube blockage, but all of them were cured immediately and no death occurred.

CONCLUSIONS

During the 3-year follow-up period after the operation, six patients in group B have subsidence and loosening of the internal fixator due to bone subsidence around the implant. Although immediate surgical treatment is not required, renovation surgery is inevitable in the long term.

Quantitative physical performance tests can effectively detect Degenerative Cervical Myelopathy: A systematic review and meta-analysis

PURPOSE

This review aimed to identify effective physical performance tests (PPT) as clinical outcome indicators for detecting and monitoring degenerative cervical myelopathy (DCM).

METHODS

A comprehensive literature search was performed on seven electronic databases on the effectiveness in detection and monitoring of DCM by PPT. All included studies were reviewed and undergone quality assessments on the risk-of-bias by Newcastle-Ottawa Scale and were pooled by random-effect analysis with level of significance at 0.05. Homogeneity among studies was assessed by I²-statistics and effect of PPT was confirmed by Cohen's d effect size and confidence intervals.

RESULTS

Totally, 3111 articles were retrieved, and 19 studies were included for review and meta-analysis. There were 13 studies investigating PPT regarding the upper limbs and 12 studies regarding the lower limbs. Performance in 10-second-Grip-and-Release Test (G&R) and 9-Hole-Peg Test (9HPT) was studied in 10 and 3 articles, respectively, while 10-second-Stepping Test (SST), 30-meter-Walking Test (30MWT) and Foot-Tapping Test (FTT) for lower limbs were studied in 5, 4, and 3 articles correspondingly. Only 1 study utilized the Triangle-Stepping Test. High-quality study with fair risk-of-bias was revealed from Newcastle-Ottawa scale. Large effect size facilitated detection and monitoring in DCM was unveiling for G&R, 9HPT, SST, and 30MWT. FTT, while also effective, was hindered by a high-degree heterogeneity in the meta-analysis.

CONCLUSION

Effective PPT including G&R, 9HPT, SST, 30MWT, and FTT was identified for disease detection and monitoring in DCM.

Is diabetes the risk factor for poor neurological recovery after cervical spine surgery? A review of the literature

The poor prognosis of cervical spine surgery is mainly manifested as poor neurological recovery and the presence of new upper extremity dysfunction that promotes significant psychological and physiological burdens on patients. Many factors influence the prognosis of cervical spine surgery, including the age of patients, the time and mode of surgery, and the surgical technique used. However, in clinical studies, it has been observed that patients with diabetes have a higher probability of poor prognosis after surgery. Therefore, we review the pathophysiology of diabetic neuropathies and discuss its impact on cervical nerve system function, especially in cervical nerve roots and upper limb peripheral nerve conduction.

New anterior controllable antedisplacement and fusion surgery for cervical ossification of the posterior longitudinal ligament: a biomechanical study

OBJECTIVE

The traditional anterior approach for multilevel severe cervical ossification of the posterior longitudinal ligament (OPLL) is demanding and risky. Recently, a novel surgical procedure-anterior controllable antedisplacement and fusion (ACAF)-was introduced by the authors to deal with these problems and achieve better clinical outcomes. However, to the authors' knowledge, the immediate and long-term biomechanical stability obtained after this procedure has never been evaluated. Therefore, the authors compared the postoperative biomechanical stability of ACAF with those of more traditional approaches: anterior cervical discectomy and fusion (ACDF) and anterior cervical corpectomy and fusion (ACCF).

METHODS

To determine and assess pre- and postsurgical range of motion (ROM) (2 Nm torque) in flexion-extension, lateral bending, and axial rotation in the cervical spine, the authors collected cervical areas (C1-T1) from 18 cadaveric spines. The cyclic fatigue loading test was set up with a 3-Nm cycled load (2 Hz, 3000 cycles). All samples used in this study were randomly divided into three groups according to surgical procedures: ACDF, ACAF, and ACCF. The spines were tested under the following conditions: 1) intact state flexibility test; 2) postoperative model (ACDF, ACAF, ACCF) flexibility test; 3) cyclic loading (n = 3000); and 4) fatigue model flexibility test.

RESULTS

After operations were performed on the cadaveric spines, the segmental and total postoperative ROM values in all directions showed significant reductions for all groups. Then, the ROMs tended to increase during the fatigue test. No significant crossover effect was detected between evaluation time and operation method. Therefore, segmental and total ROM change trends were parallel among the three groups. However, the postoperative and fatigue ROMs in the ACCF group tended to be larger in all directions. No significant differences between these ROMs were detected in the ACDF and ACAF groups.

CONCLUSIONS

This in vitro biomechanical study demonstrated that the biomechanical stability levels for ACAF and ACDF were similar and were both significantly greater than that of ACCF. The clinical superiority of ACAF combined with our current results showed that this procedure is likely to be an acceptable alternative method for multilevel cervical OPLL treatment.

A Tapered Cuff Tracheal Tube Decreases the Need for Cuff Pressure Adjustment After Surgical Retraction During Anterior Cervical Spine Surgery: A Randomized Controlled, Double-Blind Trial

Background

Surgical retraction to expose the vertebrae during anterior cervical spine surgery increases tracheal tube cuff pressure and may worsen postoperative sore throat and dysphonia. This randomized double-blind study investigated the effect of cuff shape on intraoperative cuff pressure and postoperative sore throat and dysphonia.

Methods

Eighty patients were randomized to tracheal intubation with a tapered cuff or a conventional cylindrical high-volume low-pressure cuff (control) during anesthesia. Intraoperative cuff pressures were compared. The primary outcome was the incidence of pressure adjustment needed when the cuff pressure increased to &gt; 25 mm Hg after surgical retraction. The secondary outcome was the incidence of postoperative sore throat and dysphonia.

Results

The incidence of pressure adjustment after surgical retraction was significantly lower in the tapered group than in the control group (13% vs. 48%; P = 0.001; relative risk reduction, 74%). The median [interquartile range (IQR)] cuff pressure (mm Hg) was significantly lower for the tapered cuff than for the control cuff before surgical retraction [9 (7–12) vs. 12 (10–15); P &lt; 0.001] and after retraction [18 (15–23) vs. 25 (18–31); P = 0.007]. The median (IQR) postoperative dysphonia score assessed by a single speech-language pathologist was lower in the tapered group than in the control group [4 (3–6) vs. 5.5 (5–7); P = 0.008].

Conclusion

A tapered cuff tracheal tube decreased the need for the adjustment of cuff pressure after surgical retraction during anterior cervical spine surgery, thereby avoiding intraoperative pressure increase. It also has a better outcome in terms of dysphonia.

Clinical Trial Registration

[www.clinicaltrials.gov], identifier [NCT04591769].

Degenerative cervical myelopathy: Neuroradiological, neurophysiological and clinical correlations in 27 consecutive cases

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New insight into prognostic factors for recovery of clinical function following posterior decompression for degenerative cervical myelopathy.

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An increase of IOM amplitude of at least 50% coupled with preoperative T2-only and diffuse T2 signal changes on MRI is a positive prognostic factors for clinical improvement 6 months after surgery.

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Clinical improvement at 6 months follow-up can be expected in patients with T1 hypo intensity if a diffuse border of the lesion on T2 images is present.

Efficacy of Intraoperative Neuromonitoring Using Transcranial Motor-Evoked Potentials for Degenerative Cervical Myelopathy: A Prospective Multicenter Study by the Monitoring Committee of the Japanese Society for Spine Surgery and Related Research

STUDY DESIGN

A prospective multicenter observational study.

OBJECTIVE

To elucidate the efficacy of transcranial motor-evoked potentials (Tc(E)-MEPs) in degenerative cervical myelopathy (DCM) surgery by comparing cervical spondylotic myelopathy (CSM) to cervical ossification of the posterior longitudinal ligament (OPLL) and investigate the timing of Tc(E)-MEPs alerts and types of interventions affecting surgical outcomes.

SUMMARY OF BACKGROUND DATA

Although CSM and OPLL are the most commonly encountered diseases of DCM, the benefits of Tc(E)-MEPs for DCM remain unclear and comparisons of these two diseases have not yet been conducted.

METHODS

We examined the results of Tc(E)-MEPs from 1176 DCM cases (840 CSM /336 OPLL) and compared patients background by disease, preoperative motor deficits, and the type of surgical procedure. We also assessed the efficacy of interventions based on Tc(E)-MEPs alerts. Tc(E)-MEPs alerts were defined as an amplitude reduction of more than 70% below the control waveform. Rescue cases were defined as those in which waveform recovery was achieved after interventions in response to alerts and no postoperative paralysis.

RESULTS

Overall sensitivity was 57.1%, and sensitivity was higher with OPLL (71.4%) than with CSM (42.9%). The sensitivity of acute onset segmental palsy including C5 palsy was 40% (OPLL/CSM: 66.7%/0%) whereas that of lower limb palsy was 100%. The most common timing of Tc(E)-MEPs alerts was during decompression (63.16%), followed by screw insertion (15.79%). The overall rescue rate was 57.9% (OPLL/CSM: 58.3%/57.1%).

CONCLUSION

Since Tc(E)-MEPs are excellent for detecting long tract injuries, surgeons need to consider appropriate interventions in response to alerts. The detection of acute onset segmental palsy by Tc(E)-MEPs was partially possible with OPLL, but may still be difficult with CSM. The rescue rate was higher than 50% and appropriate interventions may have prevented postoperative neurological complications.Level of Evidence: 3.

Smoking and degenerative spinal disease: A systematic review

Smoking is a major cause of morbidity and mortality worldwide and is responsible for the death of more than 8 million people per year globally. Through a systematic literature review, we aim to review the harmful effects of tobacco smoking on degenerative spinal diseases (DSD). DSD is a debilitating disease and there is a need to identify if smoking can be an attributable contender for the occurrence of this disease, as it can open up avenues for therapeutic options. Sources such as PubMed and Embase were used to review literature, maintaining tobacco smoking and spinal diseases as inclusion factors, excluding any article that did not explore this relationship. Risk of bias was assessed using analysis of results, sample size and methods and limitations. Upon review of the literature, tobacco smoking was found to be a major risk factor for the occurrence of DSDs, particularly lumbar spinal diseases. Smokers also experienced a greater need for surgery and greater postoperative wound healing complications, increased pain perception, delay in recovery and decreased satisfaction after receiving surgery. These effects were noted along the entire spine. Many mechanisms of action have been identified in the literature that provide plausible pictures of how smoking leads to spinal degeneration, exploring possible primary targets which can open up opportunities to develop potential therapeutic agents. More studies on cervical and thoracic spinal degeneration would be beneficial in identifying the effect of nicotine on these spinal levels. Some limitations included insufficient sample size, inconclusive evidence and lack of sufficient repeat studies. However, there appears to be a sufficient amount of research on smoking directly contributing to lumbar spinal pathology.

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Smoking is a risk factor for the occurence of degenerative spinal disease (DSD).

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There are numerous pathological mechanisms attributed to spinal pathology by smoking.

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Smoking appears to be a significant risk factor for lumbar DSDs, with smoke studies also suggesting its role in cervical DSDs.

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There is insufficient research on the effect of smoking on the thoracic spine.

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Smoking leads to worse outcomes and potential complications post-surgery, as well as increased pain perception and poorer subjective response post-surgery.

Factors Significantly Associated with Postoperative Neck Pain Deterioration after Surgery for Cervical Ossification of the Posterior Longitudinal Ligament: Study of a Cohort Using a Prospective Registry

Postoperative neck pain has been reported as an unsolved postoperative complication of surgery for cervical ossification of the posterior longitudinal ligament (OPLL). The aim of the present study was to elucidate factors having a significant association with postoperative deterioration of neck pain in cervical OPLL patients. We studied a cohort of patients in a prospective registry of 478 patients who had undergone cervical spine surgery for cervical OPLL. We excluded those without evaluation of preoperative neck pain. Therefore, 438 patients were included in the present study. Neck pain was evaluated with the visual analogue scale (VAS, 0-100 mm). Postoperative neck pain deterioration was defined as a ≥20 mm increase of VAS neck pain. Patient factors, neurological status, imaging factors and surgical factors were assessed. Univariate analyses followed by multivariate analysis using stepwise logistic regression was performed. Six months after surgery, 50 (11.6%) patients showed postoperative neck pain deterioration and 76 (17.4%) patients showed postoperative neck pain deterioration 2 years after surgery. Six months after surgery, the rate of neck pain deterioration was significantly higher in patients who had undergone posterior surgery. Two years after surgery, the number of levels fused was significantly correlated with neck pain deterioration.

[Effect of prophylactic C 4, 5 foraminal dilatation in posterior cervical open-door surgery on postoperative C 5 nerve root palsy syndrome]

Objective

To investigate the effect of prophylactic C _{4, 5} foraminal dilatation in posterior cervical open-door surgery on postoperative C ₅ nerve root palsy syndrome.

Methods

The clinical data of patients with cervical spondylotic myelopathy (cervical spinal cord compression segments were more than 3) who met the selection criteria between March 2016 and March 2019 were retrospectively analyzed. Among them, 40 patients underwent prophylactic C _{4, 5} foraminal dilatation in posterior cervical open-door surgery (observation group) and 40 patients underwent simple posterior cervical open-door surgery (control group). There was no significant difference between the two groups ( P>0.05) in gender, age, disease duration, Nurick grade of spinal cord symptoms, and preoperative diameter of C _{4, 5} intervertebral foramen, Japanese Orthopaedic Association (JOA) score, and visual analogue scale (VAS) score. The occurrence of C ₅ nerve root paralysis syndrome was recorded and compared between the two groups, including incidence, paralysis time, recovery time, and spinal cord drift. VAS and JOA scores were used to evaluate the improvement of pain and function before operation and at 12 months after operation.

Results

The incisions of the two groups healed by first intention, and there was no early postoperative complications such as cerebrospinal fluid leakage. Patients of both groups were followed up 12-23 months, with an average of 17.97 months. C ₅ nerve root paralysis syndrome occurred in 8 cases in the observation group (3 cases on the right and 5 cases on the left) and 2 cases in the control group (both on the right). There was significant difference of the incidence (20% vs. 5%) between the two groups ( χ ²=4.114, P=0.043). Except for 1 case in the observation group who developed C ₅ nerve root palsy syndrome at 5 days after operation, the rest patients all developed at 1 day after operation; the recovery time of the observation group and the control group were (3.87±2.85) months and (2.50±0.70) months respectively, showing no significant difference between the two groups ( t=-0.649, P=0.104). At 12 months after operation, the JOA score and VAS score of cervical spine in the two groups significantly improved when compared with those before operation ( P<0.05); there was no significant difference in the difference of the cervical spine JOA score and VAS score between at 12 months after operation and before operation and the degree of spinal cord drift between the two groups ( P>0.05).

Conclusion

Prophylactic C _{4, 5} foraminal dilatation can not effectively prevent and reduce the occurrence of postoperative C ₅ root palsy, on the contrary, it may increase its incidence, so the clinical application of this procedure requires caution.

Machine learning algorithms for prediction of health-related quality-of-life after surgery for mild degenerative cervical myelopathy

BACKGROUND

Degenerative cervical myelopathy (DCM) is the most common cause of spinal cord dysfunction worldwide. Current guidelines recommend management based on the severity of myelopathy, measured by the modified Japanese Orthopedic Association (mJOA) score. Patients with moderate to severe myelopathy, defined by an mJOA below 15, are recommended to undergo surgery. However, the management for mild myelopathy (mJOA between 15 and 17) is controversial since the response to surgery is more heterogeneous.

PURPOSE

To develop machine learning algorithms predicting phenotypes of mild myelopathy patients that would benefit most from surgery.

STUDY DESIGN

Retrospective subgroup analysis of prospectively collected data.

PATIENT SAMPLES

Data were obtained from 193 mild DCM patients who underwent surgical decompression and were enrolled in the multicenter AOSpine CSM clinical trials.

OUTCOME MEASURES

The mJOA score, an assessment of functional status, was used to isolate patients with mild DCM. The primary outcome measures were change from baseline for the Short Form-36 (SF-36) mental component summary (MCS) and physical component summary (PCS) at 1-year postsurgery. These changes were dichotomized according to whether they exceeded the minimal clinically important difference.

METHODS

The data were split into training (75%) and testing (25%) sets. Model predictors included baseline demographic variables and clinical presentation. Seven machine learning algorithms and a logistic regression model were trained and optimized using the training set, and their performances were evaluated using the testing set. For each outcome (improvement in MCS or PCS), the machine learning algorithm with the greatest area under the curve (AUC) on the training set was selected for further analysis.

RESULTS

The generalized boosted model (GBM) and earth models performed well in the prediction of significant improvement in MCS and PCS respectively, with AUCs of 0.72 to 0.78 on the training set. This performance was replicated on the testing set, in which the GBM and earth models showed AUCs of 0.77 and 0.78, respectively, as well as fair to good calibration across the predicted range of probabilities. Female patients with a low initial MCS were less likely to experience significant improvement in MCS than males. The presence of certain signs and symptoms (eg, lower limb spasticity, clumsy hands) were also predictive of worse outcome.

CONCLUSIONS

Machine learning models showed good predictive power and provided information about the phenotypes of mild DCM patients most likely to benefit from surgical intervention. Overall, machine learning may be a useful tool for management of mild DCM, though external validation and prospective analysis should be performed to better solidify its role.

Early Major Complications After Radical Resection of Primary C2-Involved Upper Cervical Chordoma Through the Combined Anterior Retropharyngeal-Posterior Approach: Incidence and Risk Factors

BACKGROUND

We investigated the frequency of postoperative major complications, length of stay (LOS), and associated risk factors for primary C2-involved upper cervical chordoma through the combined anterior retropharyngeal-posterior approach.

METHODS

Clinical data were collected from 102 patients with primary C2-involved upper cervical chordoma treated at our institute from January 2016 to January 2021. Additionally, the Changzheng Hospital (CZH) surgical classification system was designed to describe the different anatomic types of C2 chordomas. A multivariate logistic regression analysis was performed and a multivariate Cox proportional hazards model was used to identify the risk factors associated with the occurrence of major complications and prolonged length of stay (LOS), respectively.

RESULTS

The incidence of major complication was 29.41% (30 of 102) in our cohort. A long surgical duration (P = 0.001), increased age (P = 0.001), more preoperative comorbidities (P = 0.008) and CZH types indicating extensive tumor involvement (P < 0.001) were identified as significant predictors of the occurrence of a major complication postoperatively. The mean LOS for the entire study population was 21.50 ± 0.64 days. The patients who experienced complications required a significant longer LOS (25.50 ± 1.26 days) than those without complications (19.83 ± 0.65; P < 0.001). The independent factors affecting LOS included age (P = 0.001), Frankel grade (P = 0.001), CZH classification (P < 0.001), and surgical duration (P = 0.001).

CONCLUSIONS

Patients who are older, experience longer operative duration, or have larger tumor extension have a greater risk of postoperative major complication. The LOS can be predicted by age, preoperative neurological deficit, CZH classification, surgical approach, and surgical duration. Accordingly, patients with these risk factors should be monitored and targeted with preventative measures.

Risk factors for surgical complications in the management of ossification of the posterior longitudinal ligament

BACKGROUND CONTEXT

Ossification of the posterior longitudinal ligament (OPLL) is a progressive, debilitating disease most commonly affecting the cervical spine. When compared to other degenerative pathologies, OPLL procedures carry a significantly higher risk of complications owing to increased case complexity and technical difficulties. Most previous studies have focused on functional outcomes and few have reported on risk factors for postoperative complications in OPLL patients.

PURPOSE

To identify clinical and radiological risk factors of surgical complications following treatment for cervical OPLL STUDY DESIGN: Retrospective review PATIENT SAMPLE: One hundred thirty-one patients with cervical myelopathy secondary to OPLL who underwent surgical decompression with complete 2-year follow-up.

OUTCOME MEASURES

Surgical and medical postoperative complications were analyzed. Revision surgery rates and mortality rates were recorded.

METHODS

Clinical, surgical, and radiological characteristics were collected for each patient. Complications within 30 days were identified. Univariate and multivariate analysis were performed to identify risk factors for surgical complications.

RESULTS

There were 39 (29.8%) surgical complications in the cohort, which included C5 palsy (7.6%), dural tear (3.1%), surgical site infection (3.1%), and epidural hematoma (1.5%). 2-year revision and mortality rates were 4.6% and 2.3%, respectively. Univariate analysis revealed that blood loss ≥750mL (OR 3.42, p=0.028), operative duration ≥5.5 hours (OR 3.16, p=0.008), hill-type OPLL (OR 3.08, p=0.011), K-line (-) OPLL (OR 5.39, p<0.001), and presence of a double-layer sign (OR 3.79, p=0.002) were significant risk factors. In multivariate analysis, only hill-type OPLL (OR 2.61, p=0.048) and K-line (-) OPLL (OR 2.98, p=0.031) were found to be significant. Patients with both hill-type and K-line (-) OPLL had a 3.5 times risk of developing surgical complications (p=0.009).

CONCLUSIONS

Patients with OPLL have a higher risk of perioperative surgical complications if they had a hill-shaped OPLL and K-line (-) OPLL on preoperative imaging studies. To the best of the authors' knowledge, this study is the first to link hill-type and K-line (-) OPLL morphology as risk factors for perioperative surgical complications.

Surgical outcomes in rigid versus flexible cervical deformities

OBJECTIVE

Cervical deformity (CD) patients have severe disability and poor health status. However, little is known about how patients with rigid CD compare with those with flexible CD. The main objectives of this study were to 1) assess whether patients with rigid CD have worse baseline alignment and therefore require more aggressive surgical corrections and 2) determine whether patients with rigid CD have similar postoperative outcomes as those with flexible CD.

METHODS

This is a retrospective review of a prospective, multicenter CD database. Rigid CD was defined as cervical lordosis (CL) change < 10° between flexion and extension radiographs, and flexible CD was defined as a CL change ≥ 10°. Patients with rigid CD were compared with those with flexible CD in terms of cervical alignment and health-related quality of life (HRQOL) at baseline and at multiple postoperative time points. The patients were also compared in terms of surgical and intraoperative factors such as operative time, blood loss, and number of levels fused.

RESULTS

A total of 127 patients met inclusion criteria (32 with rigid and 95 with flexible CD, 63.4% of whom were females; mean age 60.8 years; mean BMI 27.4); 47.2% of cases were revisions. Rigid CD was associated with worse preoperative alignment in terms of T1 slope minus CL, T1 slope, C2-7 sagittal vertical axis (cSVA), and C2 slope (C2S; all p < 0.05). Postoperatively, patients with rigid CD had an increased mean C2S (29.1° vs 22.2°) at 3 months and increased cSVA (47.1 mm vs 37.5 mm) at 1 year (p < 0.05) compared with those with flexible CD. Patients with rigid CD had more posterior levels fused (9.5 vs 6.3), fewer anterior levels fused (1 vs 2.0), greater blood loss (1036.7 mL vs 698.5 mL), more 3-column osteotomies (40.6% vs 12.6%), greater total osteotomy grade (6.5 vs 4.5), and mean osteotomy grade per level (3.3 vs 2.1) (p < 0.05 for all). There were no significant differences in baseline HRQOL scores, the rate of distal junctional kyphosis, or major/minor complications between patients with rigid and flexible CD. Both rigid and flexible CD patients reported significant improvements from baseline to 1 year according to the numeric rating scale for the neck (-2.4 and -2.7, respectively), Neck Disability Index (-8.4 and -13.3, respectively), modified Japanese Orthopaedic Association score (0.1 and 0.6), and EQ-5D (0.01 and 0.05) (p < 0.05). However, HRQOL changes from baseline to 1 year did not differ between rigid and flexible CD patients.

CONCLUSIONS

Patients with rigid CD have worse baseline cervical malalignment compared with those with flexible CD but do not significantly differ in terms of baseline disability. Rigid CD was associated with more invasive surgery and more aggressive corrections, resulting in increased operative time and blood loss. Despite more extensive surgeries, rigid CD patients had equivalent improvements in HRQOL compared with flexible CD patients. This study quantifies the importance of analyzing flexion-extension images, creating a prognostic tool for surgeons planning CD correction, and counseling patients who are considering CD surgery.

Efficacy and safety of Shi-style cervical manipulation therapy for treating acute and subacute neck pain: study protocol for a randomized controlled trial

Background

Neck pain is a common clinical disease, which seriously affects people’s mental health and quality of life and results in loss of social productivity. Improving neck pain’s curative effect and reducing its recurrence rate are major medical problems. Shi’s manipulation therapy has unique advantages and technical features that aid in the diagnosis and treatment of neck pain. Compared with first-line non-steroidal anti-inflammatory drug (NSAID) treatment of neck pain, Shi’s cervical manipulation lacks the relevant research basis of therapeutic advantage, safety, and satisfaction for treating acute and subacute neck pain. Herein, we aim to confirm our hypothesis in a clinical trial that the safety and efficacy of Shi’s cervical manipulation will be more effective, safer, and more satisfactory than NSAIDs to treat acute and subacute neck pain.

Methods

In this multicenter, positive-controlled, randomized clinical trial, traditional analgesic drug (NSAID) is used to evaluate and show that Shi’s manipulation is more effective, safe, and satisfactory for treating acute and subacute neck pain. Overall, 240 subjects are randomly divided into the trial and control groups, with both groups treated by the corresponding main intervention method for up to 12 weeks. Clinical data will be collected before the intervention and immediately after the first treatment; at 3 days and 1, 2, 4, 8, and 12 weeks after the intervention; and at 26 and 52 weeks after treatment follow-up of clinical observation index data collection. The clinical observation indices are as follows: (1) cervical pain is the primary observation index, measured by Numerical Rating Scale. The secondary indices include the following: (2) cervical dysfunction index, measured by patient self-evaluation using cervical Neck Disability Index; (3) cervical activity measurement, measured by the cervical vertebra mobility measurement program of Android mobile phone system; (4) overall improvement, measured by patient self-evaluation with SF-36; and (5) satisfactory treatment, determined by patient self-evaluation.

Discussion

We will discuss whether Shi’s cervical manipulation has greater advantages in efficacy, safety, and satisfaction of acute and subacute neck pain than traditional NSAIDs, to provide a scientific basis for the dissemination and application of Shi’s cervical manipulation.

Trial registration

China Registered Clinical Trial Registration Center ChiCTR1900021371. Registered on 17 February 2019

Morbidity and mortality following degenerative spine surgery in a prospective cohort of 1687 consecutive surgical procedures

STUDY DESIGN

Prospective, observational cohort study.

OBJECTIVE

To determine the true incidence of adverse events (AEs) in European adults undergoing surgery for degenerative spine diseases. The majority of surgeries performed for degenerative spinal diseases are elective, and the need for adequate estimation of risk-benefit of the intended surgery is imperative. A cumbersome obstacle for adequate estimation of surgery-related risks is that the true incidence of complications or adverse events (AEs) remains unclear.

METHODS

All adult patients (≥ 18 years) undergoing spine surgery at a single center from February 1, 2016, to January 31, 2017, were prospectively and consecutively included. Morbidity and mortality were determined using the Spine AdVerse Events Severity (SAVES) system. Additionally, the correlation between the AEs and length of stay (LOS) and mortality was assessed.

RESULTS

A total of 1687 procedures were performed in the study period, and all were included for analysis. Of these, 1399 (83%) were lumbar procedures and 288 (17%) were cervical. The overall incidence of AEs was 47.4%, with a minor AE incidence of 43.2% and a major of 14.5%. Female sex (OR 1.5 [95% CI 1.2-1.9), p < 0.001) and age > 65 years (OR 1.5 [95% CI 1.1-1.7], p = 0.012) were significantly associated with increased odds of having an AE.

CONCLUSION

Based on prospectively registered AEs in this single-center study, we validated the use of the SAVES system in a European population undergoing spine surgery due to degenerative spine disease. We found a higher incidence of AEs than previously reported in retrospective studies. The major AEs registered occurred significantly more often perioperatively and in patients > 65 years.

Effects of Preservation of the Semispinalis Cervicis Inserted into C2 on Craniocervical Alignment After Laminoplasty

OBJECTIVE

The preservation of nuchal musculature is essential for preventing axial pain and cervical malalignment after laminoplasty. A few studies have examined the effect of preservation of nuchal musculature on the degenerative progression after laminoplasty. We aimed to clarify the influence of preservation of the semispinalis cervicis inserted into C2 on cervical degenerative change and alignment after laminoplasty.

METHODS

We retrospectively reviewed 106 consecutive patients who underwent C3-7 laminoplasty for cervical spondylotic myelopathy during 2006-2017. Patients were classified into 2 groups according to the preservation (P-group; n = 33) or detachment (D-group; n = 73) of the Semispinalis cervicis muscles inserted into the C2 spinous process. Parameters of cervical sagittal alignment, range of motion, and progressive degenerative changes next to or within the range of laminoplasty were evaluated in cervical spine radiographs, and magnetic resonance images obtained during follow-up period.

RESULTS

In the D-group, the postoperative C2-7 Cobb angle significantly decreased (-0.06°/month), while the O-C2 Cobb angle significantly increased (0.07°/month). In addition, the C2-7 range of motion significantly decreased in the D-group (-0.12°/month). Degenerative changes in the laminoplasty range were found in 5 patients per group. Three patients from the D-group developed retroodontoid pseudotumors (P < 0.001).

CONCLUSIONS

To maintain horizontal gaze, the craniocervical segment can compensate for the loss of lordosis by increasing the Cobb angle. Excessive compensation may exert mechanical stress on the atlantoaxial junction, contributing to the development of a retroodontoid pseudotumor. Preservation of the semispinalis cervicis inserted into C2 is critical for the prevention of malalignment after laminoplasty.

Comparative Five-Year Surgical Outcomes of Open-Door versus French-Door Laminoplasty in Multilevel Cervical Spondylotic Myelopathy

Objective

To compare the five-year surgical outcomes between Open-Door laminoplasty (ODL) and French-Door laminoplasty (FDL) in the management of multilevel cervical spondylotic myelopathy (MCSM).

Methods

Sixty patients with MCSM, who were operated by ODL or FDL, were included in this study and followed up for at least 5 years. The average follow-up period was 69.2 ± 3.2 months. The modified Japanese Orthopaedic Association (mJOA) score and radiological assessments including the Cobb angle and cervical range of motion (ROM) were evaluated and compared before surgery and at the final follow-up. The incidence of postoperative complications and medical costs were also compared.

Results

Both ODL and FDL groups achieved significant improvements of the mJOA score in postoperative 5 years; the average recovery rate (RR) of the mJOA score in the ODL and FDL groups was 72.14 ± 6.97% and 69.53 ± 7.51%, respectively. No statistically significant differences regarding the pre- and postoperative mJOA score, the RR of the mJOA score, the loss and the loss rate of the Cobb angle, and the incidence of postoperative complications existed between ODL and FDL. The mean loss and the loss rate of cervical ROM in the FDL group (18.70 ± 8.91°, 41.08 ± 11.17%) were significantly higher than those of the ODL group (13.81 ± 8.62°, 31.47 ± 12.43%) (P < 0.05). FDL reduced medical costs more greatly than ODL (33014.37 ± 3424.12 China Yuan versus 82096.62 ± 7093.07 China Yuan, P < 0.001).

Conclusions

Both ODL and FDL are effective for MCSM. The 5-year neurological results are similar between the two groups. ODL trends to be superior to FDL in postoperative preservation of cervical ROM while FDL reduced medical costs more greatly.

Frailty Is a Better Predictor than Age of Mortality and Perioperative Complications after Surgery for Degenerative Cervical Myelopathy: An Analysis of 41,369 Patients from the NSQIP Database 2010-2018

Background: The ability of frailty compared to age alone to predict adverse events in the surgical management of Degenerative Cervical Myelopathy (DCM) has not been defined in the literature. Methods: 41,369 patients with a diagnosis of DCM undergoing surgery were collected from the National Surgical Quality Improvement Program (NSQIP) Database 2010–2018. Univariate analysis for each measure of frailty (modified frailty index 11- and 5-point; MFI-11, MFI-5), modified Charlson Co-morbidity index and ASA grade) were calculated for the following outcomes: mortality, major complication, unplanned reoperation, unplanned readmission, length of hospital stay, and discharge to a non-home destination. Multivariable modeling of age and frailty with a base model was performed to define the discriminative ability of each measure. Results: Age and frailty have a significant effect on all outcomes, but the MFI-5 has the largest effect size. Increasing frailty correlated significantly with the risk of perioperative adverse events, longer hospital stay, and risk of a non-home discharge destination. Multivariable modeling incorporating MFI-5 with age and the base model had a robust predictive value (0.85). MFI-5 had a high categorical assessment correlation with a MFI-11 of 0.988 (p < 0.001). Conclusions and Relevance: Measures of frailty have a greater effect size and a higher discriminative value to predict adverse events than age alone. MFI-5 categorical assessment is essentially equivalent to the MFI-11 score for DCM patients. A multivariable model using MFI-5 provides an accurate predictive tool that has important clinical applications.

Study protocol for an observational study of cerebrospinal fluid pressure in patients with degenerative cervical myelopathy undergoing surgical deCOMPression of the spinal CORD: the COMP-CORD study

INTRODUCTION

Degenerative cervical myelopathy (DCM) is a disabling spinal disorder characterised by sensorimotor deficits of upper and lower limbs, neurogenic bladder dysfunction and neuropathic pain. When suspected, cervical MRI helps to reveal spinal cord compression and rules out alternative diagnoses. However, the correlation between radiological findings and symptoms is weak. Cerebrospinal fluid pressure (CSFP) analysis may complement the appreciation of cord compression and be used for intraoperative and postoperative monitorings in patients undergoing surgical decompression.

METHODS AND ANALYSIS

Twenty patients diagnosed with DCM undergoing surgical decompression will receive standardised lumbar CSFP monitoring immediately before, during and 24 hours after operation. Rest (ie, opening pressure, CSF pulsation) and stimulated (ie, Valsalva, Queckenstedt's) CSFP-findings in DCM will be compared with 20 controls and results from CSFP monitoring will be related to clinical and neurophysiological findings. Arterial blood pressure will be recorded perioperatively and postoperatively to calculate spinal cord perfusion pressure and spinal vascular reactivity index. Furthermore, measures of CSFP will be compared with markers of spinal cord compression by means of MR imaging.

ETHICS AND DISSEMINATION

The study protocol conformed to the latest revision of the Declaration of Helsinki and was approved by the local Ethics Committee of the University Hospital of Zurich (KEK-ZH number PB-2016-00623). The main publications from this study will cover the CSFP fluid dynamics and pressure analysis preoperative, perioperative and postoperative correlated with imaging, clinical scores and neurophysiology. Other publications will deal with preoperative and postoperative spinal perfusion. Furthermore, we will disseminate an analysis on waveform morphology and the correlation with blood pressure and ECG. Parts of the data will be used for computational modelling of cervical stenosis.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov Registry (NCT02170155).

Multidisciplinary approach to degenerative cervical myelopathy

INTRODUCTION

Degenerative cervical myelopathy (DCM) is a prevalent condition causing significant impairment spanning several domains of health. A multidisciplinary approach to the care of DCM would be ideal in utilizing complex treatments from different disciplines to address broad patient needs.

AREAS COVERED

In this article the authors will discuss the importance of multidisciplinary care and establish a general framework for its use. The authors will then highlight the potential role of a multidisciplinary team in each aspect of DCM care including assessment, diagnosis, decision-making, surgical intervention, non-operative therapy, monitoring, and postoperative care.

EXPERT OPINION

In order to provide comprehensive personalized care to DCM patients, it is necessary to have a multidisciplinary team composed by a combination of the patient, surgeon, primary care practitioner, neurologist, anesthesiologist, radiologist, physiatrist, nurses, physiotherapist, occupational therapist, pain specialist, and social workers all functioning independently and communicating to achieve a common goal.

Snake-Eye Myelopathy and Surgical Prognosis: Case Series and Systematic Literature Review

The prognostic value of "snake-eyes" sign in spinal cord magnetic resonance imaging (MRI) is unclear and the correlation with different pathological conditions has not been completely elucidated. In addition, its influence on surgical outcome has not been investigated in depth. A literature review according to PRISMA (Preferred reporting items for systematic review and meta-analysis protocols) guidelines on the prognostic significance of "snake-eyes" sign in operated patients was performed. Clinical, neuroradiological, and surgical data of three institutional patients, were also retrospectively collected. The three patients, with radiological evidence of "snake-eyes" myelopathy, underwent appropriate surgical treatment for their condition, with no new post-operative neurological deficits and good outcome at follow-up. The literature review, however, reported conflicting results: the presence of "snake-eyes" sign seems a poor prognostic factor in degenerative cervical myelopathy, even if some cases can improve after surgery. "Snake-eyes" myelopathy represents a rare form of myelopathy; pathophysiology is still unclear. The frequency of this myelopathy may be greater than previously thought and according to our literature review it is mostly a negative prognostic factor. However, from our experience, prognosis might not be so dire, especially when tailored surgical intervention is performed; therefore, surgery should always be considered and based on the complete clinical, neurophysiological, and radiological data.

Tackling Research Inefficiency in Degenerative Cervical Myelopathy: Illustrative Review

Background

Degenerative cervical myelopathy (DCM) is widely accepted as the most common cause of adult myelopathy worldwide. Despite this, there is no specific term or diagnostic criteria in the International Classification of Diseases 11th Revision and no Medical Subject Headings (MeSH) or an equivalent in common literature databases. This makes searching the literature and thus conducting systematic reviews or meta-analyses imprecise and inefficient. Efficient research synthesis is integral to delivering evidence-based medicine and improving research efficiency.

Objective

This study aimed to illustrate the difficulties encountered when attempting to carry out a comprehensive and accurate evidence search in the field of DCM by identifying the key sources of imprecision and quantifying their impact.

Methods

To identify the key sources of imprecision and quantify their impact, an illustrative search strategy was developed using a validated DCM hedge combined with contemporary strategies used by authors in previous systematic reviews and meta-analyses. This strategy was applied to Medical Literature Analysis and Retrieval System Online (MEDLINE) and Excerpta Medica dataBASE (EMBASE) databases looking for relevant DCM systematic reviews and meta-analyses published within the last 5 years.

Results

The MEDLINE via PubMed search strategy returned 24,166 results, refined to 534 papers after the application of inclusion and exclusion criteria. Of these, 32.96% (176/534) results were about DCM, and 18.16% (97/534) of these were DCM systematic reviews or meta-analyses. Non-DCM results were organized into imprecision categories (spinal: 268/534, 50.2%; nonspinal: 84/534, 15.5%; and nonhuman: 8/534, 1.5%). The largest categories were spinal cord injury (75/534, 13.67%), spinal neoplasms (44/534, 8.24%), infectious diseases of the spine and central nervous system (18/534, 3.37%), and other spinal levels (ie, thoracic, lumbar, and sacral; 18/534, 3.37%). Counterintuitively, the use of human and adult PubMed filters was found to exclude a large number of relevant articles. Searching a second database (EMBASE) added an extra 12 DCM systematic reviews or meta-analyses.

Conclusions

DCM search strategies face significant imprecision, principally because of overlapping and heterogenous search terms, and inaccurate article indexing. Notably, commonly employed MEDLINE filters, human and adult, reduced search sensitivity, whereas the related articles function and the use of a second database (EMBASE) improved it. Development of a MeSH labeling and a standardized DCM definition would allow comprehensive and specific indexing of DCM literature. This is required to support a more efficient research synthesis.

Progression Prediction of Mild Cervical Spondylotic Myelopathy by Somatosensory-evoked Potentials

STUDY DESIGN

Retrospective study to correlate classification of somatosensory-evoked potentials (SEPs) with symptomatic progress of patients with mild cervical spondylotic myelopathy (CSM).

OBJECTIVE

The aim of this study was to evaluate the usefulness of SEPs for predicting symptomatic progress of mild CSM.

SUMMARY OF BACKGROUND DATA

SEPs have been used for clinical diagnosis and intraoperative neuromonitoring in patients with CSM. However, the prognostic value of SEPs in predicting the progression of CSM remains unclear.

METHODS

A total of 200 patients with a clinical diagnosis of mild CSM were enrolled between September 2014 and February 2018. All patients received clinical assessment with the modified Japanese Orthopedic Association scale (mJOA), magnetic resonance imaging, and SEP tests in the first clinical visit and at 1-year follow-up. A classification of upper and lower limbs SEP was developed. At 1-year follow-up, patients with symptom decline >2 points in mJOA were considered progressive myelopathy cases. The relationship of progressive myelopathy and classifications of SEP was investigated.

RESULTS

Fifty-four of 200 cases presented with progressive myelopathy. The incidence of progressive myelopathy was 2.6%, 27.7%, 23.8%, 86.7%, and 100% in Class I, II, III, IV, and V of upper SEPs, respectively, and 18.8%, 39.4%, 42.3%, and 62.5% in Class I, II, III, and IV of lower SEPs, respectively. For the combination classification of upper and lower SEPs, the incidence of progressive myelopathy was 0%, 13.7%, 24.3%, 91.1%, and 100% in Class I, II, III, IV, and V, respectively. There was a significant correlation of the incidence of progressive myelopathy with SEP classification for the upper SEPs (r = 0.94, P < 0.01) and the combination SEPs (r = 0.95, P < 0.01).

CONCLUSION

The incidence of progressive degenerative myelopathy increased with the upper and combination SEP classifications. Thus, classification of SEPs could predict the clinical decline in mJOA in CSM, reflecting the probability of worsening of myelopathy.

LEVEL OF EVIDENCE

4.

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.

Ten-Year Surgical Outcomes and Prognostic Factors for French-Door Laminoplasty in the Treatment of Multilevel Cervical Spondylotic Myelopathy

Objective

To analyze the ten-year surgical outcomes and postoperative complications of French-Door laminoplasty (FDL) in the management of multilevel cervical spondylotic myelopathy (MCSM) and analyze the prognostic factors for FDL in treating MCSM.

Methods

64 patients with MCSM, who were operated by FDL, were included in this study and followed up for at least 10 years. Clinical assessments including modified Japanese Orthopaedic Association (mJOA) score, age at surgery, preoperative symptom duration, operative time, blood loss and postoperative complications, radiological assessments including Cobb angle, cervical range of motion (ROM), intramedullary signal intensity on T2W MRI, canal narrowing ratio (CNR), and maximum spinal cord compression (MSCC). mJOA score, Cobb angle, cervical ROM, intramedullary signal intensity on T2W MRI, and CNR were assessed before surgery and at the final follow-up.

Results

The average mJOA score was significantly improved from preoperative 10.32 ± 1.63 points to 15.10 ± 0.62 points at the final follow-up (p < 0.05). The average RR of the mJOA score at the final follow-up was 69.10 ± 7.32%. The cervical Cobb angle and ROM decreased significantly at the final follow-up. Patients with high intramedullary signal intensity of T2W MRI or CNR more than 50% showed a lower RR of the mJOA score. Correlation analysis revealed that preoperative symptom duration and intramedullary signal intensity of T2W MRI, CNR, MSCC, and blood loss were significantly correlated with the RR of the mJOA score. Gender, operative method, and age at surgery were significantly correlated with the preservation rate of ROM. Operative time was significantly correlated with the incidence of axial symptoms.

Conclusions

The ten-year clinical outcomes of FDL were satisfactory. Higher intramedullary signal intensity of T2W MRI and a greater CNR predicted poorer prognoses.

How common is repeat surgery and multi-level treatment in Degenerative Cervical Myelopathy? Findings from a patient perspective survey

Degenerative Cervical Myelopathy (DCM) is a common condition which causes significant disability and reduces health-related quality of life. The only evidence-based treatment and current management guidance is surgery to decompress the spinal cord and stop further damage in moderate to severe cases. However, this guidance is mainly informed by studies that only include first time surgery and/or single level disease, but DCM can reoccur after primary surgery and affect multiple levels of the spine. It is unclear whether patients in these subgroups; repeat surgery and multi-level DCM, differ significantly in their baseline and disease characteristics from those with single-level, single-operation disease. To investigate this, we conducted an online survey of people with DCM looking at key demographic, disease (e.g. mJOA) and treatment characteristics. We received a total of 778 respondents, of which 159 (20%) had undergone surgery for DCM. Around 75% of these respondents had a single operation and 65% at a single level. We found no statistically significant difference in key participant and disease characteristics between respondents with single-level or single-operation and those with multi-level DCM or multiple operations. These data support generalisability of research to these subgroups but also warrants further investigations as these subgroups are underrepresented in current research.

Risk Factors for Medical and Surgical Complications After Single-Level Minimally Invasive Transforaminal Lumbar Interbody Fusion

Background

The prevention of perioperative and postoperative complications is necessary to avoid poor postoperative outcomes and increased costs. Previous investigations have identified risk factors for complications after various spine procedures, but no such study exists in a population solely undergoing minimally invasive transforaminal lumbar interbody fusion (MIS TLIF). The purpose of this study is to determine risk factors for the development of complications up to 2 years after MIS TLIF procedures.

Methods

Patients who underwent primary, single-level MIS TLIF from 2007 to 2016 were retrospectively reviewed. The incidence of medical and surgical complications up to 2 years postoperatively was determined. Patients were categorized according to demographic, comorbidity, and procedural characteristics. Bivariate Poisson regression with robust error variance was used to determine if an association existed between patient characteristics and complication incidence. A final multivariate model including all patient characteristics as controls was created using backwards, stepwise regression until only those variables with P < .05 remained.

Results

390 patients were analyzed. Upon bivariate analysis, age >50 years (P = .025), diabetes mellitus (P = .001), and operative duration >105 minutes (P = .016) were associated with increased medical complication rates. Regarding surgical complications, age ≤50 years (P < .001), obesity (P = .012), and diabetes mellitus (P = .042) were identified as risk factors on bivariate analysis. Upon final multivariate analysis, operative time >105 minutes (P = .009) and diabetes mellitus (P = .001) were independent risk factors for medical complications. Independent risk factors for surgical complications on multivariate analysis included age ≤50 years (P < .001), diabetes mellitus (P = .002), and obesity (P = .030).

Conclusions

Diabetic patients and those who underwent longer operations were at increased risk of medical complications, while younger patients, obese patients and those also with diabetes mellitus were at increased risk of surgical complications up to 2 years after MIS TLIF. Practitioners can use this information to identify patients who require preventative care before their procedure or increased postoperative vigilance and monitoring after single-level MIS TLIF.

Level of Evidence

3.

Risk factors associated with reoperation in posterior cervical fusions: A large-scale retrospective analysis

OBJECTIVES

To identify risk factors for reoperation in patients who have undergone posterior cervical fusion (PCF).

PATIENTS AND METHODS

A retrospective cohort analysis was performed of patients undergoing PCF during a 12-year period at a single institution. Demographic and surgical characteristics were collected from electronic medical records. This study addressed reoperations, from all causes, of PCF. Different strategies, including the addition of anterior fusion, were also compared.

RESULTS

Of the 370 patients meeting inclusion criteria there were 44 patients (11.9 %) that required a revision and of those 5 required a second revision. The most common reasons for revision were adjacent segment disease and infection, 13 (3.5 %) and 11 patients (3.0 %), respectively. There was not a higher revision rate (for any cause) for patients who had a subaxial fusion and compared with those that included C2 or those that failed to cross the cervicothoracic junction. Of patients who required reoperation, there was a statistically significant higher fraction of smokers (p =  0.023).

CONCLUSION

The risks and benefits of posterior cervical instrumentation and fusion should be thoroughly discussed with patients. This report implicates smoking as a risk factor for all-cause reoperation in patients who have had this PCF and provides surgeons with additional data regarding this complication. When possible, preoperative optimization should include smoking cessation therapy.