The optimal radiologic method for assessing spinal canal compromise and cord compression in patients with cervical spinal cord injury. Part II: Results of a multicenter study

Reproducible Spinal Cord Quantitative MRI Analysis with the Spinal Cord Toolbox

The spinal cord plays a pivotal role in the central nervous system, providing communication between the brain and the body and containing critical motor and sensory networks. Recent advancements in spinal cord MRI data acquisition and image analysis have shown a potential to improve the diagnostics, prognosis, and management of a variety of pathological conditions. In this review, we first discuss the significance of standardized spinal cord MRI acquisition protocol in multi-center and multi-manufacturer studies. Then, we cover open-access spinal cord MRI datasets, which are important for reproducible science and validation of new methods. Finally, we elaborate on the recent advances in spinal cord MRI data analysis techniques implemented in the open-source software package Spinal Cord Toolbox (SCT).

Three-dimensional Spinal Canal Morphometric Analysis and Relevant Spinal Cord Occupational Ratios in Congenital Cervical Spinal Stenosis: A Classification Algorithm of the Stenosis Phenotypes and Data-driven Decompression Approach

OBJECTIVES

No standardized magnetic resonance imaging (MRI) parameters have defined the 3-dimensional morphoanatomy and relevant spinal cord occupation ratios (occupation of spinal cord dimensions/similar dimensions within the spinal canal) in congenital cervical stenosis (CCS).

METHODS

A retrospective, comparative analysis was conducted on 200 patients >18 years of age with myelopathy and CCS (mean age, 52.4 years) and 200 age-matched controls with no myelopathy or radiculopathy. The variables assessed from high resolution MRI included sagittal and axial spinal canal dimensions (MRI Torg-Pavlov ratios) from C3 to C7. Morphometric dimensions from the sagittal retrodiscal and retrovertebral regions as well as axial MRI dimensions were compared. Sagittal and axial spinal cord occupation ratios were defined and correlated with spinal canal dimensions.

RESULTS

Multivariate analyses indicated reduced sagittal and axial anteroposterior (AP) spinal canal dimensions and a large reduction in transverse spinal canal dimensions at all spinal levels. There was a small significant correlation between AP sagittal spinal canal dimensions and axial transverse spinal canal dimensions at C3-C5, but not at C5-C6. Small correlations were noted between AP sagittal spinal canal dimensions and AP axial spinal cord and axial cross-sectional area occupation ratios at C3-C6, but there was no correlation with axial mediolateral spinal cord occupation ratios.

CONCLUSIONS

The stenosis effect can involve any dimension, including the transverse spinal canal dimension, independent of other dimensions. Owing to the varied observed morphoanatomies, a classification algorithm that defines CCS specific phenotypes was formulated. Objectivizing the stenosis morphoanatomy may allow for data-driven patient-focused decompression approaches in the future.

Morphological Changes of Deep Extensor Neck Muscles in Relation to the Maximum Level of Cord Compression and Canal Compromise in Patients With Degenerative Cervical Myelopathy

STUDY DESIGN

Cross-sectional study.

OBJECTIVES

To examine the relationship between morphological changes of the deep extensor neck muscles in patients with degenerative cervical myelopathy (DCM) and the level of maximum spinal cord compression (MSCC) and canal compromise (MCC). A secondary objective was to examine the relationship between muscle morphological changes with neck pain and functional scores related to neck pain and interference.

METHODS

A total of 171 patients with DCM were included. Total cross-sectional area (CSA), functional CSA (fat free area, FCSA), ratio of FCSA/CSA (fatty infiltration) and asymmetry of the multifidus (MF) and semispinalis cervicis (SCer) together, and cervical muscle as a group (eg, MF, SCer, semispinalis capitis, splenius capitis) were obtained from T2-weighted axial MR images at mid-disc, at the level of maximum cord compression and the level below. The relationship between the muscle parameters of interest, MSCC, MCC and functional scores including the Neck Disability Index (NDI) was assessed using multivariate linear regression models, adjusting for age, body mass index and sex.

RESULTS

Greater MF + Scer fatty infiltration was associated with greater MCC (P = .032) and MSCC (P = .049) at the same level. Greater asymmetry in MF + SCer CSA was also associated with greater MCC (P = .006). Similarly, greater asymmetry in FCSA and FCSA/CSA of the entire extensor muscle was associated with greater MCC (P = .011, P = .013). There was a negative association between asymmetry in FCSA MF + SCer, FCSA/CSA MF + SCer and FCSA/CSA group muscles with NDI score at the level below.

CONCLUSION

Greater MCC is associated with increased fatty infiltration and greater asymmetry of the deep cervical muscles in patients with DCM. A negative association between muscle asymmetry and NDI scores was also observed which has implications for clinical prediction around axial neck pain.

The Quality of Life of the Patients with Thoracic Ossification of the Ligamentum Flavum after Surgery Using EQ-5D-5L

OBJECTIVE

There is a lack of studies on the quality of life (QoL) after posterior laminectomy in patients with thoracic ossification of the ligamentum flavum (TOLF), and risk factors associated with poor prognosis remain controversial. Therefore, the present study was conducted to illustrate the QoL for TOLF patients after surgery and determine its relationship with their demographic, surgery-related, clinical characteristics and imaging data.

METHODS

One hundred and eighteen patients diagnosed with thoracic myelopathy because of TOLF were enrolled in this retrospective study. They all underwent posterior decompressive laminectomy from August 2010 to January 2022. The QoL was evaluated based on the EQ-5D-5L. Collecting gender, age, number of operations, compressed segments, Frankel grade, complications, body mass index (BMI), symptoms and duration, modified Japanese Orthopaedic Association (mJOA) score (preoperative), follow-up time and type of ossification, increased signal on Sagittal T2-weighted Images (ISST2I), occupancy rate and analyzing by Mann-Whitney U-test, Kruskal-Wallis test, the χ2 -test, and logistic regression tests.

RESULTS

Average follow-up 70.8 months (18-149), the mean age was 59.74 ± 9.81 years and the mean score for the QoL based on the EQ-5D-5 L and visual analogue scale (VAS) score were 0.71 ± 0.28 and 78.88 ± 10.21 at the final follow-up. Moderate and severe problems were found in the pain/discomfort in 22.0% of the patients. These mobility and usual activities numbers were slightly higher (24.6% and 30.4%, respectively). The mean scores for QoL and VAS were significantly higher in patients with mild and moderate neurological impairment, normal BMI, <60 years of age, no dural tears, symptom relief at hospital discharge, unilateral and bilateral ossification on axial CT scan, ≤ 50% spinal canal occupancy on CT and MRI, and none or fuzzy on ISST2I.

CONCLUSION

QoL after posterior laminectomy in TOLF patients is generally satisfactory compared to preoperative levels. Preoperative mJOA score, Age, comorbid diabetes, the major symptom is activity limitation, BMI, ISST2I, Intraoperative dural tears and spinal canal occupancy rate correlate significantly with the corresponding dimensions and are predictive. Age, spinal canal occupancy rate, ISST2I, preoperative mJOA score, BMI are significantly associated with and have predictive value for overall postoperative QoL.

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

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

A future blood test for acute traumatic spinal cord injury

Acute spinal cord injury (SCI) requires prompt diagnosis and intervention to minimize the risk of permanent neurologic deficit. Presently, SCI diagnosis and interventional planning rely on magnetic resonance imaging (MRI), which is not always available or feasible for severely injured patients. Detection of disease-specific biomarkers in biofluids via liquid biopsy may provide a more accessible and objective means of evaluating patients with suspected SCI. Cell-free DNA, which has been used for diagnosing and monitoring oncologic disease, may detect damage to spinal cord neurons via tissue-specific methylation patterns. Other types of biomarkers, including proteins and RNA species, have also been found to reflect neuronal injury and may be included as part of a multi-analyte assay to improve liquid biopsy performance. The feasibility of implementing liquid biopsy into current practices of SCI management is supported by the relative ease of blood sample collection as well as recent advancements in droplet digital polymerase chain reaction technology. In this review, we detail the current landscape of biofluid biomarkers for acute SCI and propose a framework for the incorporation of a putative blood test into the clinical management of SCI.

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.

The Role of Magnetic Resonance Imaging and Computed Tomography in Spinal Cord Injury

Traumatic injuries of the spine are associated with long-term morbidity and mortality. Timely diagnosis and appropriate management of mechanical instability and spinal cord injury are important to prevent further neurologic deterioration. Spine surgeons require an understanding of the essential imaging techniques concerning the diagnosis, management, and prognosis of spinal cord injury. We present a review in the role of computed tomography (CT) including advancements in multidetector CT (MDCT), dual energy CT (DECT), and photon counting CT, and how it relates to spinal trauma. We also review magnetic resonance imaging (MRI) and some of the developed MRI based classifications for prognosticating the severity and outcome of spinal cord injury, such as diffusion weighted imaging (DWI), diffusion tractography (DTI), functional MRI (fMRI), and perfusion MRI.

Utility of MRI in Quantifying Tissue Injury in Cervical Spondylotic Myelopathy

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

Prognostic value of early magnetic resonance imaging in the morbidity and mortality of traumatic spinal cord injury

OBJECTIVE

To assess in individuals with traumatic spinal cord injury (TSCI) the relationship between mortality and need for ICU and early magnetic resonance imaging (MRI), analyzing spinal parenchymal alterations, disruption of vertebral ligaments (DVL) and spinal cord compression (SCC).

DESIGN

Retrospective study.

SETTING

Third-level hospital, Spinal Cord Injury Unit and ICU.

PATIENTS

Individuals with acute TSCI between 2010 and 2019.

INTERVENTION

Analysis of MRI performed in the first 72 h.

VARIABLES OF INTEREST

Admission to ICU and mortality.

RESULTS

269 cases collected. The pattern that demonstrated higher mortality was cord hemorrhage (16.7%) for 12.5% ​​of single-level edema and 6.5% of multilevel edema (p = 0.125). The same happened with ICU admissions: 69.0% in hemorrhage, 60.2% in multilevel edema and 46.3% in short edema (p = 0.018). Analyzing CCM, mortality was 13.4% with 59.2% of ICU admissions, for 2.2% and 42.2% of individuals without cord compression (p = 0.020 and p = 0.003). The figures of death and ICU admission among cord injuries with DVL were 15.0% and 67.3%, for 6.2% and 44.4% of the individuals without DLV (p < 0.001 and p = 0.013).

CONCLUSIONS

The presence of spinal cord hemorrhage, SCC and DVL was associated with a higher admission in ICU. A significant increase in mortality was observed in cases with SCC and DVL.

Efficacy of a machine learning-based approach in predicting neurological prognosis of cervical spinal cord injury patients following urgent surgery within 24 h after injury

We aimed to develop a machine learning (ML) model for predicting the neurological outcomes of cervical spinal cord injury (CSCI). We retrospectively analyzed 135 patients with CSCI who underwent surgery within 24 h after injury. Patients were assessed with the American Spinal Injury Association Impairment Scale (AIS; grades A to E) 6 months after injury. A total of 34 features extracted from demographic variables, surgical factors, laboratory variables, neurological status, and radiological findings were analyzed. The ML model was created using Light GBM, XGBoost, and CatBoost. We evaluated Shapley Additive Explanations (SHAP) values to determine the variables that contributed most to the prediction models. We constructed multiclass prediction models for the five AIS grades and binary classification models to predict more than one-grade improvement in AIS 6 months after injury. Of the ML models used, CatBoost showed the highest accuracy (0.800) for the prediction of AIS grade and the highest AUC (0.90) for predicting improvement in AIS. AIS grade at admission, intramedullary hemorrhage, longitudinal extent of intramedullary T2 hyperintensity, and HbA1c were identified as important features for these prediction models. The ML models successfully predicted neurological outcomes 6 months after injury following urgent surgery in patients with CSCI.

Evaluation of the prognostic value of extra-parenchymal changes in traumatic spinal cord injury, assessed by magnetic resonance imaging

OBJECTIVES

To analyze the relationship between neurological progression following traumatic spinal cord injury and Spinal Cord Compression (SCC) and Spinal Ligamentous Injury (LI) by magnetic resonance imaging.

DESIGN

Retrospective observational study.

SETTING

Spinal Cord Injury Unit (A Coruña, Spain).

PARTICIPANTS

Patients were admitted for traumatic spinal cord injury between January 2010 and December 2018 with a magnetic resonance imaging examination performed during the acute phase.

INTERVENTION

Evaluation of SCC and LI by magnetic resonance imaging.

OUTCOME MEASURES

Comparisons between neurological examination at admission and discharge were made, assessing ASIA Impairment Scale (AIS) grade and motor score.

RESULTS

Data from 296 patients were collected. A relationship between SCC and LI and complete injuries were found (P < 0.001). Improvement of the AIS grade was observed in 31.6% of patients with SCC and 31.3% with LI versus 42.7% and 37.8% of subjects without these complications, respectively. Regarding motor score, patients with SCC had lower mean values at the beginning (46.9 ± 26.8 versus 61.1 ± 29.9 in the control group, P < 0.001), as well as less improvement when assessed by the percentage of change (35.1 ± 37.5% versus 49.4 ± 38.1% in the control group, P = 0.010). Similar results were obtained in cases with LI: mean motor score at admission was 45.9 ± 26.7 versus 54.9 ± 29.4 in the control group (P = 0.014) and the percentage of change was 28.5 ± 37.1% in comparison to 46.0 ± 37.5% (P = 0.001) in the controls.

CONCLUSIONS

There is a relationship between SCC and LI and complete spinal cord injury. This patient population has lower possibilities of improving their AIS grade and motor score.

Surgical Efficacy and Prognostic Factors for Acute Traumatic Central Cord Syndrome Without Fracture and Dislocation

This study was undertaken to evaluate the effectiveness of surgical treatment of acute traumatic central cord syndrome (ATCCS) without fracture and dislocation and explore surgical timing and factors influencing postoperative recovery of spinal cord function. We retrospectively collected the general and clinical data of 112 patients with ATCCS (American Spinal Injury Association impairment scale grade C or D) without fracture and dislocation who underwent surgical treatment in our hospital from January 2013 to August 2019. We used statistical methods to evaluate the safety of the operation and explore the timing of surgery and the factors influencing postoperative recovery of spinal cord function. The mean age of the 112 patients was 60.64±12.91 years. The Japanese Orthopaedic Association score and the American Spinal Injury Association motor score (AMS) of the 112 patients were significantly higher at final follow-up than at admission. No significant difference in recovery of spinal cord function was seen between the early operation group (≤4 days) and the late operation group (>4 days). Comparison of patients with a good prognosis vs a poor prognosis showed that age, intrahand muscle strength at admission, maximum spinal cord compression, maximum canal compromise, length of high-intensity signal in the spinal cord on sagittal T2-weighted magnetic resonance imaging, AMS, and American Spinal Injury Association injury grade D/C at admission had a significant effect on recovery of spinal cord function. Surgical treatment of ATCCS without fracture and dislocation is safe and effective. Age, admission AMS and American Spinal Injury Association impairment scale score, intrinsic hand muscle strength, maximum canal compromise, maximum spinal cord compression, and length of high-intensity signal in the spinal cord can be used to predict postoperative recovery of spinal cord function. [Orthopedics. 2022;45(6):325-332.].

Predicting the Role of Preoperative Intramedullary Lesion Length and Early Decompressive Surgery in ASIA Impairment Scale Grade Improvement Following Subaxial Traumatic Cervical Spinal Cord Injury

BACKGROUND

 Traumatic cervical spinal cord injury (TCSCI) is a disabling condition with uncertain neurologic recovery. Clinical and preclinical studies have suggested early surgical decompression and other measures of neuroprotection improve neurologic outcome. We investigated the role of intramedullary lesion length (IMLL) on preoperative magnetic resonance imaging (MRI) and the effect of early cervical decompressive surgery on ASIA impairment scale (AIS) grade improvement following TCSCI.

METHODS

 In this retrospective study, we investigated 34 TCSCI patients who were admitted over a 12-year period, from January 1, 2008 to January 31, 2020. We studied the patient demographics, mode of injury, IMLL and timing of surgical decompression. The IMLL is defined as the total length of edema and contusion/hemorrhage within the cord. Short tau inversion recovery (STIR) sequences or T2-weighted MR imaging with fat saturation increases the clarity of edema and depicts abnormalities in the spinal cord. All patients included had confirmed adequate spinal cord decompression with cervical fixation and a follow-up of at least 6 months.

RESULTS

 Of the 34 patients, 16 patients were operated on within 24 hours (early surgery group) and 18 patients were operated on more than 24 hours after trauma (delayed surgery group). In the early surgery group, 13 (81.3%) patients had improvement of at least one AIS grade, whereas in the delayed surgery group, AIS grade improvement was seen in only in 8 (44.5%) patients (early vs. late surgery; odds ratio [OR] = 1.828; 95% confidence interval [CI]: 1.036-3.225). In multivariate regression analysis coefficients, the timing of surgery and intramedullary edema length on MRI were the most significant factors in improving the AIS grade following cervical SCI. Timing of surgery as a unique variance predicted AIS grade improvement significantly (p < 0.001). The mean IMLL was 41.47 mm (standard deviation [SD]: 18.35; range: 20-87 mm). IMLL was a predictor of AIS grade improvement on long-term outcome in bivariate analysis (p < 0.001). This study suggests that patients who had IMLL of less than 30 mm had a better chance of grade conversion irrespective of the timing of surgery. Patients with an IMLL of 31 to 60 mm had chances of better grade conversion after early surgery. A longer IMLL predicts lack of improvement (p < 0.05). If the IMLL is greater than 61 mm, the probability of nonconversion of AIS grade is higher, even if the patient is operated on within 24 hours of trauma.

CONCLUSION

 Surgical decompression within 24 hours of trauma and shorter preoperative IMLL are significantly associated with improved neurologic outcome, reflected by better AIS grade improvement at 6 months' follow-up. The IMLL on preoperative MRI can reliably predict outcome after 6 months. The present study suggests that patients have lesser chances of AIS grade improvement when the IMLL is ≥61 mm.

The impact of surgical timing on motor level lowering in motor complete traumatic spinal cord injury patients

Patients with motor complete traumatic spinal cord injury (tSCI) have a low potential to recover ambulation. Motor level recovery, adjacent to the level of injury, could influence functional independency. This study addresses whether surgical timing influences motor level recovery in patients with sensorimotor complete (AIS A) and motor complete sensory incomplete (AIS B) tSCI. A retrospective cohort study was performed in the Netherlands in patients with motor complete tSCI (C2-L2), who consecutively underwent surgery between January 2010 and April 2020. Neurological examination was performed directly at presentation to the ER and at discharge from the rehabilitation facility. Motor level lowering, AIS grade and Upper and Lower Extremity Motor Score (UEMS and LEMS) recovery were calculated for patients who underwent early (<24h) and late (24h+) surgery. A total of 96 patients met the inclusion criteria. In the multivariate analysis late surgical decompression (24h+) was negatively associated with ≥1 motor level lowering and ≥2 AIS grade improvement (Odds Ratio (OR) 0.11 (95% CI: 0.01, 0.67) p=0.046, OR 0.06 (95% CI: 0.00, 047) p=0.030). The presence of sacral sparing (AIS B) at initial examination, and cervical level of the tSCI were associated with ≥1 motor level lowering. In addition, AOSpine C-type injuries were negatively associated with any type of neurological recovery, except motor level lowering. Although sensorimotor complete injuries as well as thoracolumbar injuries negatively influence neurological recovery, early surgical decompression (<24h) appears independently associated with enhanced neurological recovery in patients with traumatic spinal cord injury despite level and severity of injury.

Dynamic cervical flexion/extension atlantodental interval and functional outcome of the Harms technique for posterior C1/2 fixation: A retrospective analysis of 16 atlantoaxial subluxation cases in a tertiary medical center

BACKGROUND

The aim of this study was to assess the relationship between the atlantodental interval (ADI) on dynamic flexion/extension cervical radiographs and functional outcomes of posterior spinal fixation by the Harms technique for atlantoaxial subluxation (AAS). Dynamic flexion/extension on cervical radiographs is a standard assessment for evaluation of C1/2 instability in AAS patients. Most studies focused on postoperative ADI and functional outcome, including pain and fusion rate; only few studies compared dynamic ADI change pre- to post-operatively.

MATERIAL AND METHODS

Retrospectively, we reviewed the medical records of 16 patients who underwent posterior spinal fixation in our center from 2018 to 2019. We used dynamic cervical flexion/extension radiographs to assess the pre- to postoperative change at 12 months in ADI of flexion (ADI_f), ADI of extension (ADI_e), ADI between flexion/extension (ADI_Δ), C1/2 fusion rate and functional outcomes measured by the modified Japanese Orthopaedic Association scale (mJOA scale). Postoperative CT at 3∼12 months assessed screw positioning on the Gertzbein and Robbins classification.

RESULTS

In the 16 patients included in this study, ADI_f, ADI_e and ADI_Δ were significantly reduced, from respectively 8.0mm, 5.0mm and 3.0mm preoperatively to 4.6mm, 3.8mm and 0.8mm at 12 months' follow-up. The fusion rate was 81% and the mJOA score recovery rate was 34.9±14.7%. Although the screw malposition rate was higher than in other studies in C1(10%) and C2(20%), there were no new neurologic deficits or worsening of symptoms at follow-up.

CONCLUSIONS

The ADI_Δ showed significant reduction, showing that the Harms technique of posterior spinal fixation can effective in maintaining the stability of the atlantoaxial joint and improving functional outcome.

The Role of Magnetic Resonance Imaging to Inform Clinical Decision-Making in Acute Spinal Cord Injury: A Systematic Review and Meta-Analysis

The clinical indications and added value of obtaining MRI in the acute phase of spinal cord injury (SCI) remain controversial. This review aims to critically evaluate evidence regarding the role of MRI to influence decision-making and outcomes in acute SCI. A systematic review and meta-analysis were performed according to PRISMA methodology to identify studies that address six key questions (KQs) regarding diagnostic accuracy, frequency of abnormal findings, frequency of altered decision-making, optimal timing, and differences in outcomes related to obtaining an MRI in acute SCI. A total of 32 studies were identified that addressed one or more KQs. MRI showed no adverse events in 156 patients (five studies) and frequently identified cord compression (70%, 12 studies), disc herniation (43%, 16 studies), ligamentous injury (39%, 13 studies), and epidural hematoma (10%, two studies), with good diagnostic accuracy (seven comparative studies) except for fracture detection. MRI findings often altered management, including timing of surgery (78%, three studies), decision to operate (36%, 15 studies), and surgical approach (29%, nine studies). MRI may also be useful to determine the need for instrumentation (100%, one study), which levels to decompress (100%, one study), and if reoperation is needed (34%, two studies). The available literature consistently concluded that MRI was useful prior to surgical treatment (13 studies) and after surgery to assess decompression (two studies), but utility before/after closed reduction of cervical dislocations was unclear (three studies). One study showed improved outcomes with an MRI-based protocol but had a high risk of bias. Heterogeneity was high for most findings (I² > 0.75). MRI is safe and frequently identifies findings alter clinical management in acute SCI, although direct evidence of its impact on outcomes is lacking. MRI should be performed before and after surgery, when feasible, to facilitate improved clinical decision-making. However, further research is needed to determine its optimal timing, effect on outcomes, cost-effectiveness, and utility before and after closed reduction.

Subaxial spine trauma: radiological approach and practical implications

The cervical spine is part of the axial skeleton and is responsible for protecting vital structures, such as the spinal cord and the vertebral arteries and veins. Traumatic injury to the cervical spine occurs in approximately 3% of blunt trauma injuries, and approximately 80% are below the level of C2. The AO Spine society divides the spine into four segments: the upper cervical spine (C0-C2), subaxial spine (C3-C7), thoracolumbar spine, and sacral spine. Various classifications have been proposed for the subaxial segment since that of Allen and Ferguson in 1982; however, none is universally accepted, and treatment remains controversial. The complex anatomy and biomechanics of the subaxial spine and the lack of a widely accepted classification system make these injuries difficult to evaluate on imaging. The Subaxial Injury Classification System (SLIC) uses fracture morphology, the integrity of discoligamentous complex, and neurological status to score the patient and determine between operative and non-operative management; however, other factors may influence management, such as time for immobilisation, osteoporosis, surgeon's experience, and hospital circumstances. SLIC classifies fracture morphology in a crescent order of severity based on Allen and Ferguson's classification. Compression fractures are the simpler ones, while both distraction injuries and translation/rotation are severe injuries, which are always associated with some degree of discoligamentous complex (DLC) injury. This article will review the indications for imaging, the basis of the SLIC classification, the different types of fracture morphology, evaluation of the DLC, and other features important in decision making in subaxial spine trauma.

Traumatic cervical spinal cord injury: relationship of MRI findings to initial neurological impairment

PURPOSE

To quantify the degree of available space for the cord and cord swelling in patients following traumatic cervical spinal cord injury (TCSCI), and to assess the relationship among the available space for the cord, cord swelling, and the severity of neurological impairment.

METHODS

This study included 91 patients. The following indexes were measured by two blinded observers: maximum cord available area (CAA_max) and maximum cord swelling area (CSA_max). The American Spinal Injury Association (ASIA) impairment scale (AIS) grades were used to evaluate the extent of neurological injury. Relationship among CAA_max, CSA_max, and initial AIS grades was assessed via univariate and multivariate analyses.

RESULTS

Patients who were AIS grade A (complete injury) demonstrated significantly greater median CAA_max and CSA_max than AIS grade C or D (incomplete injury) (P < 0.01). Multivariate analysis identified only CAA_max (OR 20.88 [95% CI 1.50-291.21]; P = 0.024) and CSA_max (OR 17.84 [95% CI 1.15-276.56]; P = 0.039) were identified as independently influencing the likelihood of complete injury at the initial assessment. The classification accuracy was best for CAA_max and CSA_max; areas under the curve were 0.8998 (95% CI 0.7881-1.0000) and 0.9167 (95% CI 0.8293-1.0000), respectively.

CONCLUSION

The present study provides a novel radiologic method for identifying the severity of TCSCI with T2-weighted MRI findings. Greater available space for the cord (CAA_max > 38%) and cord swelling (CSA_max > 29%) can be used to identify patients at risk for TCSCI and both imaging characteristics are associated with an increased likelihood of severe neurological deficits.

LEVEL OF EVIDENCE

Diagnostic: individual cross-sectional studies with consistently applied reference standard and blinding.

Relief of Low Back Pain After Posterior Decompression for Lumbar Spinal Stenosis

STUDY DESIGN

A retrospective study.

OBJECTIVE

The aim of this study was to confirm that decompression for lumbar spinal stenosis (LSS) relieves low back pain (LBP) as adequately as it relieves leg pain and to identify predictors for inadequate LBP relief.

SUMMARY OF BACKGROUND DATA

Although decompression for LSS is generally thought to yield worse results for LBP than for leg pain, some studies have reported similar improvements in pain scores between LBP and leg pain. To treat LBP or take measures to prevent inadequate LBP relief, reliable predictors for LBP relief should be identified.

METHODS

We retrospectively reviewed 175 patients who underwent posterior element-preserving decompression and evaluated the relief of LBP and leg pain using numeric rating scales (NRSs). Associations between demographic, clinical, or imaging parameters and LBP relief at 1 and 4 years were analyzed by stepwise linear regression analyses. The imaging parameters included Modic change type 1, disc degeneration, foraminal stenosis, vertebral slipping (within Grade 1), scoliosis (<15°) and lordosis.

RESULTS

The mean improvements in LBP and leg pain NRS scores from baseline were 5.22 and 4.70 points (P = 0.064, paired t test) at 1 year and 5.12 and 4.62 points (P = 0.068) at 4 years, respectively. Poor LBP scores at 4 years were significantly associated with long-lasting LBP (beta = 0.31, P < 0.0001) and moderate or severe arm symptoms with cervical spinal cord compression or intramedullary hyperintense signal on T2-weighted MRI (beta = 0.22, P = 0.0014). The imaging parameters of the lumbar spine failed to show clear associations with poor LBP scores at 4 years, although Modic change type 1 showed a significant association with poor LBP scores at 1 year (beta = 0.28, P < 0.0001).

CONCLUSION

Posterior decompression relieves LBP as well as leg pain. Long-lasting LBP and concurrent symptomatic cervical myelopathy are important predictors for inadequate LBP relief. There were no reliable imaging parameters predictive of inadequate LBP relief.Level of Evidence: 4.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

A Prognostic Factor for Prolonged Mechanical Ventilator-Dependent Respiratory Failure after Cervical Spinal Cord Injury : Maximal Canal Compromise on Magnetic Resonance Imaging

Objective

The period of mechanical ventilator (MV)-dependent respiratory failure after cervical spinal cord injury (CSCI) varies from patient to patient. This study aimed to identify predictors of MV at hospital discharge (MVDC) due to prolonged respiratory failure among patients with MV after CSCI.

Methods

Two hundred forty-three patients with CSCI were admitted to our institution between May 2006 and April 2018. Their medical records and radiographic data were retrospectively reviewed. Level and completeness of injury were defined according to the American Spinal Injury Association (ASIA) standards. Respiratory failure was defined as the requirement for definitive airway and assistance of MV. We also evaluated magnetic resonance imaging characteristics of the cervical spine. These characteristics included : maximum canal compromise (MCC); intramedullary hematoma or cord transection; and integrity of the disco-ligamentous complex for assessment of the Subaxial Cervical Spine Injury Classification (SLIC) scoring. The inclusion criteria were patients with CSCI who underwent decompression surgery within 48 hours after trauma with respiratory failure during hospital stay. Patients with Glasgow coma scale 12 or lower, major fatal trauma of vital organs, or stroke caused by vertebral artery injury were excluded from the study.

Results

Out of 243 patients with CSCI, 30 required MV during their hospital stay, and 27 met the inclusion criteria. Among them, 48.1% (13/27) of patients had MVDC with greater than 30 days MV or death caused by aspiration pneumonia. In total, 51.9% (14/27) of patients could be weaned from MV during 30 days or less of hospital stay (MV days : MVDC 38.23±20.79 vs. MV weaning, 13.57±8.40; p<0.001). Vital signs at hospital arrival, smoking, the American Society of Anesthesiologists classification, Associated injury with Injury Severity Score, SLIC score, and length of cord edema did not differ between the MVDC and MV weaning groups. The ASIA impairment scale, level of injury within C3 to C6, and MCC significantly affected MVDC. The MCC significantly correlated with MVDC, and the optimal cutoff value was 51.40%, with 76.9% sensitivity and 78.6% specificity. In multivariate logistic regression analysis, MCC >51.4% was a significant risk factor for MVDC (odds ratio, 7.574; p=0.039).

Conclusion

As a method of predicting which patients would be able to undergo weaning from MV early, the MCC is a valid factor. If the MCC exceeds 51.4%, prognosis of respiratory function becomes poor and the probability of MVDC is increased.

Surgical Decompression for Cervical Spondylotic Myelopathy in Patients with Associated Hypertension: A Single-Center Retrospective Cohort and Systematic Review of the Literature

OBJECTIVE

To explore the relationship between spinal cord compression and hypertension through analysis of blood pressure (BP) variations in a cervical spondylotic myelopathy (CSM) cohort after surgical decompression, along with a review of the literature.

METHODS

A single-institution retrospective review of patients with CSM who underwent cervical decompression between 2016 and 2017 was conducted. Baseline clinical and imaging characteristics, preoperative and postoperative BP readings, heart rate, functional status, and pain scores were collected. In addition, a PRISMA guidelines-based systematic review was performed.

RESULTS

We identified 264 patients with CSM treated surgically; 149 (56.4%) of these had hypertension. The degree of spinal canal compromise and spinal cord compression, preoperative neurologic examination, and the presence of T2-signal hyperintensity on magnetic resonance imaging were associated with hypertension. Overall mean arterial pressure (MAP) decreased significantly at 1 and 12 months after surgery. Patients without T2-signal hyperintensity on imaging showed a MAP reduction at 12 months postoperatively, whereas those with T2-signal hyperintensity showed a transient MAP reduction at 1 month postoperatively before returning to preoperative values. At 12 months after surgery, 24 of 97 patients (24.7%) with initially uncontrolled hypertension had controlled BP values with significant reduction of MAP, systolic BP, and diastolic BP. Including the present study, 5 articles were eligible for systematic review, with all reporting a BP decrease in patients with CSM after decompression.

CONCLUSIONS

Analysis of our retrospective cohort and a systematic review suggest that cervical surgical decompression reduces BP in some patients with CSM. However, this improvement is less apparent in patients with preoperative spinal cord T2-signal hyperintensity.

Spine MRI: A Review of Commonly Encountered Emergent Conditions

Over the last 2 decades, the proliferation of magnetic resonance imaging (MRI) availability and continuous improvements in acquisition speeds have led to significantly increased MRI utilization across the health care system, and MRI studies are increasingly ordered in the emergent setting. Depending on the clinical presentation, MRI can yield vital diagnostic information not detectable with other imaging modalities. The aim of this text is to report on the up-to-date indications for MRI of the spine in the ED, and review the various MRI appearances of commonly encountered acute spine pathology, including traumatic injuries, acute non traumatic myelopathy, infection, neoplasia, degenerative disc disease, and postoperative complications. Imaging review will focus on the aspects of the disease process that are not readily resolved with other modalities.

Degenerative Cervical Myelopathy: Insights into Its Pathobiology and Molecular Mechanisms

Degenerative cervical myelopathy (DCM), earlier referred to as cervical spondylotic myelopathy (CSM), is the most common and serious neurological disorder in the elderly population caused by chronic progressive compression or irritation of the spinal cord in the neck. The clinical features of DCM include localised neck pain and functional impairment of motor function in the arms, fingers and hands. If left untreated, this can lead to significant and permanent nerve damage including paralysis and death. Despite recent advancements in understanding the DCM pathology, prognosis remains poor and little is known about the molecular mechanisms underlying its pathogenesis. Moreover, there is scant evidence for the best treatment suitable for DCM patients. Decompressive surgery remains the most effective long-term treatment for this pathology, although the decision of when to perform such a procedure remains challenging. Given the fact that the aged population in the world is continuously increasing, DCM is posing a formidable challenge that needs urgent attention. Here, in this comprehensive review, we discuss the current knowledge of DCM pathology, including epidemiology, diagnosis, natural history, pathophysiology, risk factors, molecular features and treatment options. In addition to describing different scoring and classification systems used by clinicians in diagnosing DCM, we also highlight how advanced imaging techniques are being used to study the disease process. Last but not the least, we discuss several molecular underpinnings of DCM aetiology, including the cells involved and the pathways and molecules that are hallmarks of this disease.

Outcomes and prognostic indicators in 59 paraplegic medium to large breed dogs with extensive epidural hemorrhage secondary to thoracolumbar disc extrusion

OBJECTIVE

To evaluate outcomes and prognostic factors after decompressive hemilaminectomy in paraplegic medium to large breed dogs with extensive epidural hemorrhage (DEEH) and thoracolumbar intervertebral disc extrusion (TL-IVDE).

STUDY DESIGN

Retrospective, cohort, descriptive study.

ANIMALS

Fifty-nine client-owned dogs.

METHODS

Medical records and advanced imaging were reviewed for paraplegic dogs with DEEH. Ambulatory status 6 months after surgery and postoperative complications were recorded. Multiple logistic regression models were constructed to explore prognostic factors.

RESULTS

Records of 22 dogs with and 37 dogs without pelvic limb pain perception at presentation were included. Median age of dogs was 5 years (interquartile range, 4-7), and mean weight was 26.9 kg (SD, ±9.71). Labradors and Labrador mixes were most common (17/59 [28.8%]). Recovery of ambulation occurred in 17 of 22 (77.3%) dogs with and in 14 of 37 (37.8%) dogs without pain perception prior to surgery. Progressive myelomalacia was recorded in three of 59 (5.1%) dogs, one with pain perception and two without pain perception at presentation. Postoperative complications (14/59 [23.7%]) were common. Factors independently associated with outcome included clinical severity (odds ratio [OR] 0.179, P = .005), number of vertebrae with signal interruption in half Fourier single-shot turbo spin-echo sequences (HASTEi; OR, 0.738; P = .035), and ratio of vertebral sites decompressed to HASTEi (OR, 53.79; P = .03).

CONCLUSION

Paraplegic medium to large breed dogs with DEEH have a less favorable outcome after surgical decompression than paraplegic dogs with TL-IVDE.

CLINICAL SIGNIFICANCE

Dogs with DEEH can have severe postoperative complications. Loss of pain perception and increased HASTEi are associated with a poor outcome, while more extensive decompression improves outcome.

Safety and efficacy of riluzole in patients undergoing decompressive surgery for degenerative cervical myelopathy (CSM-Protect): a multicentre, double-blind, placebo-controlled, randomised, phase 3 trial

BACKGROUND

Degenerative cervical myelopathy represents the most common form of non-traumatic spinal cord injury. This trial investigated whether riluzole enhances outcomes in patients undergoing decompression surgery for degenerative cervical myelopathy.

METHODS

This multicentre, double-blind, placebo-controlled, randomised, phase 3 trial was done at 16 university-affiliated centres in Canada and the USA. Patients with moderate-to-severe degenerative cervical myelopathy aged 18-80 years, who had a modified Japanese Orthopaedic Association (mJOA) score of 8-14, were eligible. Patients were randomly assigned (1:1) to receive either oral riluzole (50 mg twice a day for 14 days before surgery and then for 28 days after surgery) or placebo. Randomisation was done using permuted blocks stratified by study site. Patients, physicians, and outcome assessors remained masked to treatment group allocation. The primary endpoint was change in mJOA score from baseline to 6 months in the intention-to-treat (ITT) population, defined as all individuals who underwent randomisation and surgical decompression. Adverse events were analysed in the modified intention-to-treat (mITT) population, defined as all patients who underwent randomisation, including those who did not ultimately undergo surgical decompression. This study is registered with ClinicalTrials.gov, NCT01257828.

FINDINGS

From Jan 31, 2012, to May 16, 2017, 408 patients were screened. Of those screened, 300 were eligible (mITT population); 290 patients underwent decompression surgery (ITT population) and received either riluzole (n=141) or placebo (n=149). There was no difference between the riluzole and placebo groups in the primary endpoint of change in mJOA score at 6-month follow-up: 2·45 points (95% CI 2·08 to 2·82 points) versus 2·83 points (2·47 to 3·19), difference -0·38 points (-0·90 to 0·13; p=0·14). The most common adverse events were neck or arm or shoulder pain, arm paraesthesia, dysphagia, and worsening of myelopathy. There were 43 serious adverse events in 33 (22%) of 147 patients in the riluzole group and 34 serious adverse events in 29 (19%) of 153 patients in the placebo group. The most frequent severe adverse events were osteoarthrosis of non-spinal joints, worsening of myelopathy, and wound complications.

INTERPRETATION

In this trial, adjuvant treatment for 6 weeks perioperatively with riluzole did not improve functional recovery beyond decompressive surgery in patients with moderate-to-severe degenerative cervical myelopathy. Whether riluzole has other benefits in this patient population merits further study.

FUNDING

AOSpine North America.

Predictive Risk Factors of Poor Preliminary Postoperative Outcome for Thoracic Ossification of the Ligamentum Flavum

Objective

The aim of the present study was to ascertain the independent risk factors of poor preliminary outcome and to reveal the value of these factors in predicting the postoperative prognosis.

Methods

A total of 165 patients diagnosed with thoracic myelopathy because of thoracic ossification of the ligamentum flavum (TOLF) were enrolled in this retrospective study. All of them underwent posterior decompressive laminectomy surgery in our hospital from May 2016 to June 2019. The postoperative improvement of symptoms was evaluated using the modified Japanese Orthopaedic Association (mJOA) scoring system. Clinical data, such as age, sex, body mass index (BMI), duration of symptoms, history of hypertension and diabetes, tobacco use, history of drinking, symptoms of incontinence, number of compressed segments, and preoperative mJOA score, were respectively recorded. Radiologic features data included sagittal maximum spinal cord compression (MSCC), axial spinal canal occupation ratio (SCOR), grades and extension of increased signal on sagittal T2‐weighted images (ISST2I), types of increased signal on axial T2‐weighted images (ISAT2I), and the classification of ossification on axial CT scan and sagittal MRI. The t‐test, the χ²‐test, Fisher's exact test, binary logistic regression analyses, receiver operating characteristic (ROC) curves, and subgroup analyses were used to evaluate the effects of individual risk predictors on surgical outcomes.

Results

A total of 76 men and 89 women were enrolled in this study. The mean age of all patients was 58.53 years. After comparison between two groups, we found some risk factors that may be associated with postoperative outcomes, such as age, preoperative mJOA score, BMI, history of hypertension, MSCC, SCOR, grade and extension of ISST2I, type of ISAT2I, axial type of ossification, and sagittal type of ossification (P < 0.05, respectively). Binary logistic regression analysis revealed that older age (odds ratio [OR] = 1.062, 95% confidence interval [CI] = 1.006–1.121, P = 0.030), number of compressed segments (OR = 1.916, 95% CI = 1.250–2.937, P = 0.003), bilateral and bridged types of ossification (OR = 4 314, 95% CI = 1.454–8.657, P = 0.019; OR = 6.630, 95% CI = 2.580–17.530, P = 0.004), and grade 1 and 2 ISST2I (OR = 8.986, 95% CI =3.056–20.294, P < 0.001; OR = 7.552, 95% CI = 3.529–16.004, P < 0.001) were independent risk factors for a poor preliminary postoperative outcome. ROC curve analysis showed that the grade of ISST2I had an excellent discriminative power (area under the curve [AUC] = 0.817). In addition, risk factors have different values for predicting the clinical outcome in each subgroup.

Conclusion

Age, duration of symptoms, number of compressed segments, SCOR, grade, and extension of ISST2I and classification of ossification were associated with the preliminary prognosis, and the intramedullary increased signal on sagittal T2‐weighted MRI was highly predictive of poor postoperative outcome.

XGBoost, a Machine Learning Method, Predicts Neurological Recovery in Patients with Cervical Spinal Cord Injury

The accurate prediction of neurological outcomes in patients with cervical spinal cord injury (SCI) is difficult because of heterogeneity in patient characteristics, treatment strategies, and radiographic findings. Although machine learning algorithms may increase the accuracy of outcome predictions in various fields, limited information is available on their efficacy in the management of SCI. We analyzed data from 165 patients with cervical SCI, and extracted important factors for predicting prognoses. Extreme gradient boosting (XGBoost) as a machine learning model was applied to assess the reliability of a machine learning algorithm to predict neurological outcomes compared with that of conventional methodology, such as a logistic regression or decision tree. We used regularly obtainable data as predictors, such as demographics, magnetic resonance variables, and treatment strategies. Predictive tools, including XGBoost, a logistic regression, and a decision tree, were applied to predict neurological improvements in the functional motor status (ASIA [American Spinal Injury Association] Impairment Scale [AIS] D and E) 6 months after injury. We evaluated predictive performance, including accuracy and the area under the receiver operating characteristic curve (AUC). Regarding predictions of neurological improvements in patients with cervical SCI, XGBoost had the highest accuracy (81.1%), followed by the logistic regression (80.6%) and the decision tree (78.8%). Regarding AUC, the logistic regression showed 0.877, followed by XGBoost (0.867) and the decision tree (0.753). XGBoost reliably predicted neurological alterations in patients with cervical SCI. The utilization of predictive machine learning algorithms may enhance personalized management choices through pre-treatment categorization of patients.

Can MRI findings predict the outcome of cervical spinal cord Injury? a systematic review

INTRODUCTION

MRI is the established gold standard for imaging acute spinal cord injury (SCI). Our aim was to identify the prognostic value, in terms of neurological outcome, of extradural and intradural features detected on MRI performed acutely following traumatic cervical SCI.

MATERIALS AND METHODS

Several databases were systematically searched to identify potentially eligible articles until December 2019. Using a standard PRISMA template, 2606 articles were initially identified.

RESULTS

A final 6 full-text articles met the inclusion criteria and were analyzed. An extradural factor, namely the maximal spinal cord compression, was associated with poor neurological outcome and statistically significant (P = 0.02 and P = 0.001 in 2 out of 3 studies). The intradural factors of length of the cord edema (P = 0.001, P = 0.006, and P < 0.001 in 3 studies), intramedullary hemorrhage (P = 0.002, P < 0.001, P < 0.001, and P = 0.002 in 4 studies), and the length of intramedullary hemorrhage (P = 0.028, P = 0.022 in 2 studies) also significantly correlated with poor neurological recovery at follow-up.

CONCLUSION

While early MRI is established as a gold standard imaging of acute spinal trauma, it also serves to provide prognostic value on the neurological recovery. From our systematic review, there is a strong association of the extradural finding of maximal spinal cord compression, intradural MRI findings of length of cord edema, intramedullary hemorrhage, and length of intramedullary hemorrhage with neurological recovery in traumatic cervical spinal cord injuries.

LEVEL OF EVIDENCE

III.

Morphological features of thoracolumbar burst fractures associated with neurological outcome in thoracolumbar traumatic spinal cord injury

PURPOSE

To identify specific morphological characteristics in thoracolumbar burst fractures associated with neurological outcome after severe traumatic spinal cord injury (TSCI).

METHODS

We retrospectively analyzed the clinical and radiological (CT scan morphological characteristics) data of 25 consecutive patients admitted for TSCI secondary to a burst fracture at levels from T11 to L2 between 2010 and 2017 in single level-1 trauma center. We included severe TSCI, defined as American Spinal Injury Association Impairment Scale (AIS) grade A, B or C.

RESULTS

Among the 25 patients with severe TSCI, 14 were AIS A, 5 were AIS B, and 6 were AIS C upon initial preoperative neurological evaluation. The AIS grade and the burden of associated injuries (Injury Severity Score, ISS) were the only clinical factors significantly associated with poor neurological recovery. The trauma level of energy was not associated with neurological outcome. Several fractures parameters were independently related to neurological recovery: the postero-inferior corner translation, presence of retropulsed fragment comminution and complete lamina fracture. The magnitude of sagittal kyphosis angle, vertebral kyphosis index and vertebral body comminution were not associated with the neurological outcome.

CONCLUSIONS

Morphological features of the bony structures involving the spinal canal in thoracolumbar burst fractures with severe TSCI are associated with the chronic neurological outcome and could provide more insight than the AIS clinical grading. The fracture pattern may better reflect the actual level of energy transferred to the spinal cord than distinguishing between low- and high-energy trauma.

Inter-observer reliability and clinical validity of the MRI grading system for cervical central stenosis based on sagittal T2-weighted image

PURPOSE

The aim was to evaluate the inter-observer reliability of the Kang system among radiologists, residents, and clinicians and examine the correlation between radiologic and clinical findings.

METHODS

A total of 133 patients (M:F = 44:89, mean age 56 years) who underwent MRI of the cervical spine at our hospital were included. Two radiologists, two trainees, and two clinicians measured Central cervical spinal stenosis (CCSS) grade at the narrowest point according to the grading system suggested by Kang et al. A different clinician (a neurosurgeon) assessed the associated neurologic manifestations. Kappa statistics were used to analyze the inter-reader agreement among the radiologists, trainees, and clinicians. The clinical correlation (R) between grade and positive clinical manifestations (PCMs) was assessed using nonparametric correlation analysis (Spearman's correlation).

RESULTS

We found almost perfect agreement between trainees (k value = 0.890) and between radiologists (k value = 0.912) and substantial agreement between clinicians (k value = 0.691). Clinical correlations for all six readers suggested moderate correlation with R values ranging from 0.380 to 0.566. There was moderate correlation between grade and clinical manifestation within each group (R = 0.562-0.669).

CONCLUSION

The Kang MRI grading system of CCSS based on mid-sagittal MRI provides objective, reliable, and reproducible assessment regardless of field proficiency of the reader although the reproducibility of the clinician is slightly lower than radiologist and trainee of the radiology department. There was moderate correlation between image interpretation and clinical findings irrespective of the reader's main field of research.

The effect of renin-angiotensin system blockers on spinal cord dysfunction and imaging features of spinal cord compression in patients with symptomatic cervical spondylosis

BACKGROUND CONTEXT

Cervical spondylosis may lead to spinal cord compression, poor vascular perfusion, and ultimately, cervical myelopathy. Studies suggest a neuroprotective effect of renin-angiotensin system (RAS) inhibitors in the brain, but limited data exist regarding their impact on the spinal cord.

PURPOSE

To investigate whether RAS blockers and other antihypertensive drugs are correlated with preoperative functional status and imaging markers of cord compression in patients with symptomatic cervical spondylosis.

STUDY DESIGN

Retrospective observational study.

PATIENT SAMPLE

Individuals with symptomatic degenerative cervical stenosis who underwent surgery.

OUTCOME MEASURES

Imaging features of spinal cord compression and functional status (modified Japanese Orthopedic Association [mJOA] and Nurick grading scales).

METHODS

Two hundred sixty-six operative patients with symptomatic degenerative cervical stenosis were included. Demographic data, comorbidities, antihypertensive medications, and functional status (including mJOA and Nurick grading scales) were collected. We evaluated canal compromise, cord compromise, surface area of T2 signal cord change, and pixel intensity of signal cord change compared with normal cord on T2-weighted magnetic resonance imaging sequences.

RESULTS

Of 266 patients, 41.7% were women, 58.3% were men; median age was 57.2 years; 20.6% smoked tobacco; 24.7% had diabetes mellitus. One hundred forty-nine patients (55.8%) had hypertension, 142 (95.3%) of these were taking antihypertensive medications (37 angiotensin-II receptor blockers [ARBs], 44 angiotensin-converting enzyme inhibitors, and 61 other medications). Patients treated with ARBs displayed a higher signal intensity ratio (ie, less signal intensity change in the compressed cord area) compared with untreated patients without hypertension (p=.004). Patients with hypertension had worse preoperative mJOA and Nurick scores than those without (p<.001). In the multivariate analysis, ARBs remained an independent beneficial factor for lower signal intensity change (p=.04), whereas hypertension remained a risk factor for worse preoperative neurological status (p<.01).

CONCLUSIONS

In our study, patients with hypertension who were treated with RAS inhibitors had decreased T2-weighted signal intensity change than untreated patients without hypertension. Patients with hypertension also had worse preoperative functional status. Prospective case-control studies may deepen understanding of RAS modulators in the imaging and functional status of chronic spinal cord compression.

Predictors of Intraspinal Pressure and Optimal Cord Perfusion Pressure After Traumatic Spinal Cord Injury

Background/Objectives

We recently developed techniques to monitor intraspinal pressure (ISP) and spinal cord perfusion pressure (SCPP) from the injury site to compute the optimum SCPP (SCPP_opt) in patients with acute traumatic spinal cord injury (TSCI). We hypothesized that ISP and SCPP_opt can be predicted using clinical factors instead of ISP monitoring.

Methods

Sixty-four TSCI patients, grades A–C (American spinal injuries association Impairment Scale, AIS), were analyzed. For 24 h after surgery, we monitored ISP and SCPP and computed SCPP_opt (SCPP that optimizes pressure reactivity). We studied how well 28 factors correlate with mean ISP or SCPP_opt including 7 patient-related, 3 injury-related, 6 management-related, and 12 preoperative MRI-related factors.

Results

All patients underwent surgery to restore normal spinal alignment within 72 h of injury. Fifty-one percentage had U-shaped sPRx versus SCPP curves, thus allowing SCPP_opt to be computed. Thirteen percentage, all AIS grade A or B, had no U-shaped sPRx versus SCPP curves. Thirty-six percentage (22/64) had U-shaped sPRx versus SCPP curves, but the SCPP did not reach the minimum of the curve, and thus, an exact SCPP_opt could not be calculated. In total 5/28 factors were associated with lower ISP: older age, excess alcohol consumption, nonconus medullaris injury, expansion duroplasty, and less intraoperative bleeding. In a multivariate logistic regression model, these 5 factors predicted ISP as normal or high with 73% accuracy. Only 2/28 factors correlated with lower SCPP_opt: higher mean ISP and conus medullaris injury. In an ordinal multivariate logistic regression model, these 2 factors predicted SCPP_opt as low, medium–low, medium–high, or high with only 42% accuracy. No MRI factors correlated with ISP or SCPP_opt.

Conclusions

Elevated ISP can be predicted by clinical factors. Modifiable factors that may lower ISP are: reducing surgical bleeding and performing expansion duroplasty. No factors accurately predict SCPP_opt; thus, invasive monitoring remains the only way to estimate SCPP_opt.

Electronic supplementary material

The online version of this article (10.1007/s12028-018-0616-7) contains supplementary material, which is available to authorized users.

Window of opportunity for surgical decompression in patients with acute traumatic cervical spinal cord injury

OBJECTIVE

The objective of this prospective study was to determine the optimal timing for surgical decompression (SD) in patients with acute traumatic cervical spinal cord injury (tSCI) within the first 24 hours of injury.

METHODS

In successive patients with fracture and/or dislocation of the subaxial cervical spine and American Spinal Injury Association Impairment Scale (AIS) grades A-C, receiver operating characteristic curve analysis was used to determine the optimal timing for SD within the first 24 hours of cervical tSCI to obtain a neurological recovery of at least two AIS grades. Multivariate logistic regression was used to model significant neurological recovery with time to SD, degree of spinal canal compromise (SCC), and severity of injury.

RESULTS

In this cohort of 64 patients, the optimal timing for SD to obtain a significant neurological improvement was within 4 hours of injury (95% confidence interval 4-9 hours). Increasing the delay from injury to SD or the degree of SCC significantly reduced the likelihood of significant neurological improvement. Due to the strong correlation with SCC, the severity of injury was a marginally significant predictor of neurological recovery.

CONCLUSIONS

These findings indicate that in patients with acute cervical tSCI and AIS grades A-C, the optimal timing for SD is within the first 4-9 hours of injury, depending on the degree of SCC and the severity of injury. Further studies are required to better understand the interrelationships among the timing of SD, injury severity, and degree of SCC in these patients.

Cord compression defined by MRI is the driving factor behind the decision to operate in Degenerative Cervical Myelopathy despite poor correlation with disease severity

OBJECTIVES

The mainstay treatment for Degenerative Cervical Myelopathy (DCM) is surgical decompression. Not all cases, however, are suitable for surgery. Recent international guidelines advise surgery for moderate to severe disease as well as progressive mild disease. The goal of this study was to examine the factors in current practice that drive the decision to operate in DCM.

STUDY DESIGN

Retrospective cohort study.

METHODS

1 year of cervical spine MRI scans (N = 1123) were reviewed to identify patients with DCM with sufficient clinical documentation (N = 39). Variables at surgical assessment were recorded: age, sex, clinical signs and symptoms of DCM, disease severity, and quantitative MRI measures of cord compression. Bivariate correlations were used to compare each variable with the decision to offer the patient an operation. Subsequent multivariable analysis incorporated all significant bivariate correlations.

RESULTS

Of the 39 patients identified, 25 (64%) were offered an operation. The decision to operate was significantly associated with narrower non-pathological canal and cord diameters as well as cord compression ratio, explaining 50% of the variance. In a multivariable model, only cord compression ratio was significant (p = 0.017). Examination findings, symptoms, functional disability, disease severity, disease progression, and demographic factors were all non-significant.

CONCLUSIONS

Cord compression emerged as the main factor in surgical decision-making prior to the publication of recent guidelines. Newly identified predictors of post-operative outcome were not significantly associated with decision to operate.

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

Objective

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

Methods

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

Results

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

Conclusion

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

Assessment of degenerative cervical stenosis on T2-weighted MR imaging: sensitivity to change and reliability of mid-sagittal and axial plane metrics

STUDY DESIGN

A retrospective cross-sectional study.

OBJECTIVE

To assess the sensitivity to change and reliability of various mid-sagittal and axial plane metrics in the assessment of patients with single-level degenerative cervical stenosis on T2-weighted MR imaging.

SETTING

A diagnostic MR imaging facility in Sydney (Australia).

METHODS

We retrospectively reviewed T2-weighted MR images of 85 consecutive patients (48 M and 37 F) with single-level degenerative cervical stenosis. Canal compromise and cord compression were evaluated using three mid-sagittal plane metrics (M₁, M₂, and M₃) and two axial plane metrics (M₄ and M₅), at the level of stenosis and nonstenotic cephalad and caudal levels (controls). Sensitivity to change (SC) for each metric was evaluated as the percentage deviation of the measured value from the estimated normal value based on cephalad and caudal controls. Reliability for each metric was evaluated using intraclass correlation coefficients.

RESULTS

Degenerative cervical stenosis showed a bimodal distribution peaking at C5-6 (n = 32) and C3-4 (n = 29) levels. The changes in the canal and cord geometry along the rostrocaudal axis were inconsistent. Across all individual subjects (reflecting a range of stenosis severity), M₃ (-32.87% ± 10.60%) was more sensitive to change compared with M₁ (16.64% ± 16.48%) and M₂ (-23.95% ± 11.12%). Similarly, M₄ (-24.62% ± 12.17%) was more sensitive to change compared with M₅ (-6.71% ± 11.08%). The level of reliability was "moderate" to "excellent" for mid-sagittal plane measurements, and "poor" to "excellent" for axial plane measurements.

CONCLUSION

Changes in canal dimensions in the mid-sagittal plane and cord shape in the axial plane are sensitive indicators of degenerative cervical stenosis on T2-weighted MR images.

The Association between Sagittal Index, Canal Compromise, Loss of Vertebral Body Height, and Severity of Spinal Cord Injury in Thoracolumbar Burst Fractures

Aim:

Our aim was to determine whether a combination of sagittal index (SI), canal compromise (CC), and loss of vertebral body height (LVBH) is associated with the severity of neurological injury in patients with thoracolumbar burst fractures.

Materials and Methods:

Seventy-four patients with thoracolumbar burst fracture undergoing instrumentation between 2010 and 2015 were analyzed retrospectively. The degree of neurological injury was determined using the American Spinal Injury Association (ASIA) scoring system. The association between the morphology of the fracture and the severity of neurological injury was analyzed.

Results:

There was a strong association between fracture morphology and the severity of neurological injury. Of the patients, 77.5% with SI ≥20°, 81.6% with CC ≥40%, and 100% with LVBH ≥50% had lesion according to ASIA. All of 7 patients with ASIA A had SI ≥20°, CC ≥40%, and LVBH ≥50%. On the other hand, 79% of the patients with ASIA E had SI <20°, 83.7% of the patients with ASIA E had CC <40%, and all of the patients with ASIA E had LVBH <50%. SI, CC, and LVBH were lower in neurologically intact patients (ASIA E), whereas they were higher in patients with neurological deficits (ASIA A, B, C, D) (P = 0.001; P < 0.01). These measurements had 100% negative predictive values and relatively high positive predictive values.

Conclusion:

SI, CC, and LVBH are significantly associated with the severity of neurological injury in patients with thoracolumbar burst fractures. The patients with SI >25°, the patients with CC >40%, and the patients with LVBH >50% are likely to have a more severe neurological injury.

Prognostic utility of magnetic resonance imaging (MRI) in predicting neurological outcomes in patients with acute thoracolumbar spinal cord injury

PURPOSE

Utility of MRI for predicting neurological outcomes in acute cervical spinal cord injury (SCI) is well established but its value in thoracolumbar (TL) SCI needs to be evaluated.

METHODS

Seventy-six patients operated for acute TL spinal injuries between January 2014 and March 2016 were reviewed to obtain demographic details, neurology at admission and at the final follow-up. Patients were divided based on the neurology at presentation into group 1 (ASIA A), group 2 (ASIA B, C, D) and group 3 (normal neurology). Preoperative MRI and CT scans were evaluated to measure parameters like osseus canal compromise, spinal cord compression (SCC), spinal cord swelling, length of cord swelling (LOS), length of edema (LOE) and the presence of hemorrhage. The MRI parameters were compared between the groups for their predictive value of neurology on admission and at the final follow-up.

RESULTS

Of the 38 patients in group 1, six patients recovered by 1 grade, nine patients recovered by 2 grades and there was no recovery in 23 (60.5%) patients. Among group 2 patients, nine (40.9%) out of 22 recovered to ASIA E neurology. On univariate analysis, SCC (P = 0.009), LOS (P = 0.021) and length of edema (P = 0.002) were associated with complete neurological deficit at presentation. However, on multivariate regression analysis only LOE was significant (P = 0.007) in predicting neurology at admission and at follow-up.

CONCLUSION

Greater the rostrocaudal LOE, worse is the neurology at presentation, and it is associated with poor neurological recovery at follow-up. These slides can be retrieved under Electronic Supplementary Material.

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

BACKGROUND

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSION

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

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

INTRODUCTION

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

STUDY DESIGN

Retrospective chart review.

OBJECTIVES

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

AOSpine Global Survey: International Trends in Utilization of Magnetic Resonance Imaging/Computed Tomography for Spinal Trauma and Spinal Cord Injury across AO Regions

The aim of this study was to determine the current trends in magnetic resonance imaging (MRI)/computed tomography (CT) utilization for spine trauma in various clinical scenarios. We conducted a survey across six AO regions and preformed pair-wise comparisons between responses obtained from different AO regions. The survey was sent to 5813 surgeons and had a 9.6% response rate with the majority being orthopedic followed by neurosurgeons. In a neurologically intact patient, the predominant imaging modality for all AO regions was CT. For patients with spinal cord injury (SCI), the predominant choice for all AO regions was CT + MRI + x-ray except North America, which was CT + MRI; pair-wise comparisons revealed significant differences involving LATAM (Latin America) versus (Asia-Pacific [APAC], Europe [EU], and Middle East [MEA]) and APAC versus (LATAM and North America [NA]). In a patient with incomplete SCI (ISCI) who presented within 4 h and had CT, the predominant choice for all AO regions was "forgo MRI and proceed to operating room (OR)." Similar to ISCI, in a patient with complete SCI, the predominant option for all AO regions was the same as ISCI, but the range was lower. Pair-wise comparisons noted significant differences between MEA and APAC, with both exhibiting differences compare to NA, LATAM, and EU for complete and ISCI. Most AO regions obtained post-operative MRI only if there was a new deficit. In summary, decisions about the use of a particular imaging modality across AO regions appears to be influenced by the neurological status of the patient upon admission and the presence of neurological deficits post-surgery. Type of residency training and fellowship training did not have an influence on choosing the appropriate imaging modality for both intact and impaired patients. Further study is needed to determine whether accessibility to MRI would change surgeons' attitude toward obtaining MRI in patients with SCI.

Predictive Values of Magnetic Resonance Imaging Features for Tracheostomy in Traumatic Cervical Spinal Cord Injury

Objective

To evaluate the magnetic resonance (MR) imaging features that have a statistically significant association with the need for a tracheostomy in patients with cervical spinal cord injury (SCI) during the acute stage of injury.

Methods

This study retrospectively reviewed the clinical data of 130 patients with cervical SCI. We analyzed the factors believed to increase the risk of requiring a tracheostomy, including the severity of SCI, the level of injury as determined by radiological assessment, three quantitative MR imaging parameters, and eleven qualitative MR imaging parameters.

Results

Significant differences between the non-tracheostomy and tracheostomy groups were determined by the following five factors on multivariate analysis : complete SCI (p=0.007), the radiological level of C5 and above (p=0.038), maximum canal compromise (MCC) (p=0.010), lesion length (p=0.022), and osteophyte formation (p=0.015). For the MCC, the cut-off value was 46%, and the risk of requiring a tracheostomy was three times higher at an interval between 50–60% and ten times higher between 60–70%. For lesion length, the cut-off value was 20 mm, and the risk of requiring a tracheostomy was two times higher at an interval between 20–30 mm and fourteen times higher between 40–50 mm.

Conclusion

The American Spinal Injury Association grade A, a radiological injury level of C5 and above, an MCC ≥50%, a lesion length ≥20 mm, and osteophyte formation at the level of injury were considered to be predictive values for requiring tracheostomy intervention in patients with cervical SCI.