Acute cervical cord injury without fracture or dislocation of the spinal column

The biomechanical effect of different types of ossification of the ligamentum flavum on the spinal cord during cervical dynamic activities

Ossification of the ligamentum flavum (OLF) is thought to be an influential etiology of myelopathy, as thickened ligamentum flavum causes the stenosis of the vertebral canal, which could subsequently compress the spinal cord. Unfortunately, there was little information available on the effects of cervical OLF on spinal cord compression, such as the relationship between the progression of cervical OLF and nervous system symptoms during dynamic cervical spine activities. In this research, a finite element model of C1-C7 including the spinal cord featured by dynamic fluid-structure interaction was reconstructed and utilized to analyze how different types of cervical OLF affect principal strain and stress distribution in spinal cord during spinal activities towards six directions. For patients with cervical OLF, cervical extension induces higher stress within the spinal cord among all directions. From the perspective of biomechanics, extension leads to stress concentration in the lateral corticospinal tracts or the posterior of gray matter. Low energy damage to the spinal cord would be caused by the high and fluctuating stresses during cervical movements to the affected side for patients with unilateral OLF at lower grades.

Prevalence of pre-existing factors causing spinal cord compression: Is there a difference between patients suffering from cervical spinal cord injury with and without bone injury?

BACKGROUND

Recently, the prevalence of elderly patients suffering from cervical spinal cord injury (CSCI) without bone injury has been increasing in various countries. Pre-existing factors causing spinal cord compression, such as ossification of the posterior longitudinal ligament (OPLL), can increase the risk of CSCI without bone injury. However, no study has compared the prevalence of pre-existing factors between CSCI with and without bone injury. This study aimed to compare the prevalence of pre-existing factors between CSCI with and without bone injury.

METHODS

In 168 consecutive patients with CSCI, pre-existing factors including OPLL, posterior spur of the vertebral body, developmental stenosis, disc bulge and calcification of yellow ligament (CYL) were evaluated on imaging studies. The prevalence of each type of pre-existing factors was compared between patients with and without bone injury.

RESULTS

The prevalence of pre-existing factors in patients without bone injury (86%) was significantly higher than in those with bone injury (20%) (P < 0.001; odds ratio, 23.9). The most common pre-existing factor was OPLL followed by developmental stenosis, posterior spur, disc bulge and CYL in both groups. OPLL, development stenosis and posterior spur were significantly more common in patients without bone injury compared to those with bone injury (P < 0.01).

CONCLUSIONS

Prevalence of pre-existing factors, such as OPLL, development stenosis and posterior spur was significantly higher in patients without bone injury than in those with bone injury. Thus, these pre-existing factors might be a potential risk of CSCI without bone injury.

The pathophysiology of cervical spinal cord injury: what are the differences between traumatic injury and degenerative disorder

STUDY DESIGN

Retrospective comparative clinical study.

OBJECTIVE

To establish eligible diagnostic criteria for traumatic cervical spinal cord injury (TCSCI) without major fracture or dislocation and create a definitive clinical protocol by comparing the pathophysiology of CSCI in both traumatic and degenerative disorders.

SETTING

Fukuoka, Japan.

METHODS

A total of 21 TCSCI patients and 16 rapid progressive clinical deterioration of cervical spondylotic myelopathy (rp-CSM: additional cervical spinal cord injury with an existing cervical myelopathy) patients with impairment graded as C or D on the American Spinal Injury Association (ASIA) Impairment Scale were included in the study. Magnetic resonance (MR) images and ASIA motor scores were evaluated for all of the patients at the time of admission and 12 months postoperatively.

RESULTS

The T2-weighted MR images for all patients showed an abnormally high intramedullary signal in the area of the injured segment at the first examination. At 12 months post-surgery, 47.62% of patients with TCSCI and none with rp-CSM had an abnormally low intramedullary signal change on T1-weighted MR images. The neurological improvement with rp-CSM was significantly greater than that with TCSCI at 12 months postoperatively.

CONCLUSIONS

Our results suggest that the pathophysiology of CSCI between traumatic injury and degenerative disorder are similar, but not identical. The most important factor in the early pathophysiological differential diagnosis between these two pathologies is the presence of an existing cervical myelopathy. We believe that early prognosis with eligible diagnosis for CSCI may lead to early preparations for social rehabilitation in each case.

Risk Factors for Poor Prognosis of Spinal Cord Injury without Radiographic Abnormality Associated with Cervical Ossification of the Posterior Longitudinal Ligament

Purpose

To investigate the factors associated with the prognosis of spinal cord injury without radiographic abnormality (SCIWORA) accompanied by cervical ossification of the posterior longitudinal ligament (C-OPLL).

Methods

We retrospectively investigated 287 patients with SCIWORA associated with C-OPLL, who were admitted within 30 days after trauma to our facility between August 2014 and August 2018. All patients were divided into the good or poor prognosis group. Patient demographics were analyzed. Besides, occupying ratio on CT and spinal cord high signal changes in MRI T2WI were measured and recorded. Multivariate linear regression was applied to analyze the correlation of prognosis with spinal cord high signal changes in MRI T2WI, cause of injury, and occupying ratio.

Results

Occupying ratio of ossification mass was 43.5 ± 10.7% in the poor prognosis group and 27.3 ± 7.7% in the good prognosis group. The occurrence rate of high signal changes in MRI T2WI was 84.2% in the poor prognosis group and 41.3% in the good prognosis group. Poor prognosis was correlated with high occupying ratio and spinal cord high signal changes in MRI T2WI. In the patient with SCIWORA associated with C-OPLL, ROC curve of occupying ratio showed 30% as a predictor for the poor prognosis. Among the 92 patients with occupying ratio ≤ 30%, poor prognosis was observed in 5 cases (5.4%), whereas in the 72 cases with occupying ratio > 30%, poor prognosis was seen in 33 cases (45.8%). Postoperative AIS grade at final follow-up in occupying ratio > 30% group was significantly worse.

Conclusions

Patients suffering from SCIWORA with C-OPLL have poor prognosis when they have higher occupying ratio of ossification mass and spinal cord high signal changes in MRI T2WI. The cut-off value of occupying ratio for predicting the poor prognosis was 30% in patients with SCIWORA associated with C-OPLL.

Spinal Cord Signal Change on Magnetic Resonance Imaging May Predict Worse Clinical In- and Outpatient Outcomes in Patients with Spinal Cord Injury: A Prospective Multicenter Study in 459 Patients

Prognostic factors for clinical outcome after spinal cord (SC) injury (SCI) are limited but important in patient management and education. There is a lack of evidence regarding magnetic resonance imaging (MRI) and clinical outcomes in SCI patients. Therefore, we aimed to investigate whether baseline MRI features predicted the clinical course of the disease. This study is an ancillary to the prospective North American Clinical Trials Network (NACTN) registry. Patients were enrolled from 2005–2017. MRI within 72 h of injury and a minimum follow-up of one year were available for 459 patients. Patients with American Spinal Injury Association impairment scale (AIS) E were excluded. Patients were grouped into those with (n = 354) versus without (n = 105) SC signal change on MRI T2-weighted images. Logistic regression analysis adjusted for commonly known a priori confounders (age and baseline AIS). Main outcomes and measures: The primary outcome was any adverse event. Secondary outcomes were AIS at the baseline and final follow-up, length of hospital stay (LOS), and mortality. A regression model adjusted for age and baseline AIS. Patients with intrinsic SC signal change were younger (46.0 (interquartile range (IQR) 29.0 vs. 50.0 (IQR 20.5) years, p = 0.039). There were no significant differences in the other baseline variables, gender, body mass index, comorbidities, and injury location. There were more adverse events in patients with SC signal change (230 (65.0%) vs. 47 (44.8%), p < 0.001; odds ratio (OR) = 2.09 (95% confidence interval (CI) 1.31–3.35), p = 0.002). The most common adverse event was cardiopulmonary (186 (40.5%)). Patients were less likely to be in the AIS D category with SC signal change at baseline (OR = 0.45 (95% CI 0.28–0.72), p = 0.001) and in the AIS D or E category at the final follow-up (OR = 0.36 (95% CI 0.16–0.82), p = 0.015). The length of stay was longer in patients with SC signal change (13.0 (IQR 17.0) vs. 11.0 (IQR 14.0), p = 0.049). There was no difference between the groups in mortality (11 (3.2%) vs. 4 (3.9%)). MRI SC signal change may predict adverse events and overall LOS in the SCI population. If present, patients are more likely to have a worse baseline clinical presentation (i.e., AIS) and in- or outpatient clinical outcome after one year. Patients with SC signal change may benefit from earlier, more aggressive treatment strategies and need to be educated about an unfavorable prognosis.

Acute paraplegia due to thoracolumbar schwannoma following trauma: A case report and literature review

Spinal schwannomas account for one third of primary spinal neoplasms. Clinical presentation is related to the tumor location. An atypical case of acute paraplegia following a fall, on the ground of a thoracolumbar schwannoma, without intratumoral hemorrhage, in a previously asymptomatic patient is reported. A 58-year-old male patient presented with acute paraplegia, and urinary and bowel incontinence, following a fall. The patient had no previous history of back and/or leg pain or neurological symptoms. Magnetic resonance imaging revealed a subdural mass, as well as a fracture of the right T12-L1 facet joint and the right transverse process. The patient underwent emergency T11-L1 wide laminectomy, exploration of the subdural space and T10-L2 posterolateral transpedicular stabilization and fusion. An intradural, extramedullary mass, causing severe cord compression, was found and excised. Pathology revealed schwannoma, without intratumoral hemorrhage. The patient recovered completely 6 months postoperatively. To the best of our knowledge, this is the first report of spinal intradural schwannoma causing sudden paraplegia in a previously asymptomatic patient in the setting of trauma, without intratumoral hemorrhage. Emergency canal decompression and complete excision of the tumor represent the optimal management of such cases.

The biomechanical effect of preexisting different types of disc herniation in cervical hyperextension injury

OBJECTIVE

Preexisting severe cervical spinal cord compression is a significant risk factor in cervical hyperextension injury, and the neurological function may deteriorate after a slight force to the forehead. There are few biomechanical studies regarding the influence of pathological factors in hyperextension loading condition. The aim of this study is to analyze the effects of preexisting different types of cervical disc herniation and different degrees of compression on the spinal cord in cervical hyperextension.

METHOD

A 3D finite element (FE) model of cervical spinal cord was modeled. Local type with median herniation, local type with lateral herniation, diffuse type with median herniation, and diffuse type with lateral herniation were simulated in neutral and extention positions. The compressions which were equivalent to 10%, 20%, 30%, and 40% of the sagittal diameter of the spinal cord were modeled.

RESULTS

The results of normal FE model were consistent with those of previous studies. The maximum von Mises stresses appeared in the pia mater for all 32 loading conditions. The maximum von Mises stresses in extension position were much higher than in neutral position. In most cases, the maximum von Mises stresses in diffuse type were higher than in local type.

CONCLUSION

Cervical spinal cord with preexisting disc herniation is more likely to be compressed in hyperextension situation than in neutral position. Diffuse type with median herniation may cause more severe compression with higher von Mises stresses concentrated at the anterior horn and the peripheral white matter, resulting in acute central cord syndrome from biomechanical point of view.

Retro-odontoid pseudotumor with uncommon presentation of cervical spine injury

Background

We report the first case of retro‐odontoid pseudotumor with an isolated symptom of C2–C3 dysesthesia triggered by a traumatic event.

Case Presentation

An 86‐year‐old man, who was a wood craftsman for more than 50 years, presented to the emergency room with sudden‐onset severe posterior head and neck dysesthesia after accidentally falling backward. No neurological impairment of the extremities was noted. Computed tomography revealed a C2–C7 osteophyte formation, mainly in front of the vertebral bodies. Moreover, magnetic resonance imaging showed cervical spinal cord compression by a soft tissue mass posterior to the odontoid process of the axis. Therefore, we diagnosed a cervical spine injury with an isolated symptom of C2–C3 dysesthesia due to a retro‐odontoid pseudotumor. He did not undergo surgical intervention and was transferred to a rehabilitation hospital on day 11 for pain control.

Conclusion

Our report could be useful to emergency physicians dealing with similar cases of cervical symptoms following trauma.

Automated detection of cervical ossification of the posterior longitudinal ligament in plain lateral radiographs of the cervical spine using a convolutional neural network

Cervical ossification of the posterior longitudinal ligament (OPLL) is a contributing factor to spinal cord injury or trauma-induced myelopathy in the elderly. To reduce the incidence of these traumas, it is essential to diagnose OPLL at an early stage and to educate patients how to prevent falls. We thus evaluated the ability of our convolutional neural network (CNN) to differentially diagnose cervical spondylosis and cervical OPLL. We enrolled 250 patients with cervical spondylosis, 250 patients with cervical OPLL, and 180 radiographically normal controls. We evaluated the ability of our CNN model to distinguish cervical spondylosis, cervical OPLL, and controls, and the diagnostic accuracy was compared to that of 5 board-certified spine surgeons. The accuracy, average recall, precision, and F1 score of the CNN for classification of lateral cervical spine radiographs were 0.86, 0.86, 0.87, and 0.87, respectively. The accuracy was higher for CNN compared to any expert spine surgeon, and was statistically equal to 4 of the 5 experts and significantly higher than that of 1 expert. We demonstrated that the performance of the CNN was equal or superior to that of spine surgeons.

Central Cord Syndrome Redefined

This article reviews the historical origins of central cord syndrome (CCS), the mechanism of injury, pathophysiology, and clinical implications. CCS is the most common form of incomplete spinal cord injury. CCS involves a spectrum of neurologic deficits preferentially affecting the hands and arms. Evidence suggests that in the twenty-first century CCS has become the most common form of spinal cord injury overall. In an era of big data and the need to standardize this particular diagnosis to unite outcome data, we propose redefining CCS as any adult cervical spinal cord injury in the absence of fracture/dislocation.

New Grading System for Cervical Paraspinal Soft Tissue Damage After Traumatic Cervical Spinal Cord Injury Without Major Fracture Based on the Short-T1 Inversion Recovery Mid-Sagittal MRI for Prediction of Neurological Improvements: The STIR-MRI Grade

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

To develop a grading method for cervical paraspinal soft tissue damage after cervical spinal cord injury (CSCI) without major fracture based on the short T1 inversion recovery (STIR) mid-sagittal magnetic resonance image (MRI) for prediction of neurological improvements.

METHODS

This study included 34 patients with CSCI without major fracture, treated conservatively for at least 1 year and graded using the STIR-MRI Grade. This system consists of anterior grades; A0: no high-intensity area (HIA), A1: linear HIA, and A2: fusiform HIA, and posterior grades; P0: no HIA, P1: HIA not exceeding the nuchal ligament, and P2: HIA exceeding the nuchal ligament, within 24 hours postinjury. The American Spinal Injury Association impairment scale (AIS) and the Japanese Orthopedic Association (JOA) scores were examined.

RESULTS

Anterior grades were not significantly correlated with the AIS and JOA score. At both injury and final follow-up, the AIS in P2 patients was significantly more severe (P = 0.007, P = 0.015, respectively) than that in P0 patients. At the injury, the AIS in P2 patients was significantly more severe (P = 0.008) than that in P1 patients. Among P2 patients only, the JOA score at the injury (1.4 points) did not improve by the final follow-up (3.9 points). The final follow-up JOA score (3.9 points) in P2 patients was significantly lower than that (13.6 points) in P0 patients (P = 0.016).

CONCLUSIONS

Grade P2 led to poor neurological outcomes. The STIR-MRI Grade is a prognostic indicator for neurological improvements past-CSCI.

Evaluation of cervical ossification of the posterior longitudinal ligament with 3D broadband IR-prepared ultrashort echo-time imaging: a pilot study

PURPOSE

We aimed to evaluate the feasibility of 3D broadband inversion-recovery-prepared ultrashort echo-time (3D IRP UTE) imaging for assessing ossification of the posterior longitudinal ligament (OPLL).

MATERIALS AND METHODS

The study consisted of 25 consecutive patients with cervical OPLL [13 women, 12 men; mean age 66.3 (47-84) years] who underwent CT, 3T conventional MR, and 3D IRP UTE imaging studies. Two readers independently assessed the 3D IRP UTE images for the type (mixed, continuous, circumscribed, segmental) and distribution of OPLL. All readers consensually assessed the diagnostic certainty of OPLL on conventional MR and 3D IRP UTE images by using a 3-point scale system. Interobserver and intermodality agreement was assessed by κ statistics. A Wilcoxon signed-rank test was used to evaluate the difference of diagnostic certainty between conventional MR and 3D IRP UTE imaging.

RESULTS

Interobserver and intermodality agreements were good (κ = 0.73) and excellent (κ = 0.81) for the OPLL type, and excellent (κ = 0.85) and good (κ = 0.76) for the assessment of the distribution of OPLL, respectively. The mean level of the diagnostic certainty of OPLL was significantly higher for 3D IRP UTE than conventional MR imaging (p = 0.002).

CONCLUSION

3D IRP UTE imaging may be useful for assessing OPLL.

Spinal Cord Transection in a Type II Odontoid Fracture From a Ground-Level Fall

Odontoid fractures typically occur as a result of trauma: high-velocity injuries like motor vehicle accidents in young people and falls for the elderly. Odontoid fractures are the most common cervical spine fractures in patients over 65, with type II being the most common. However, spinal cord transections are rare with these types of injuries, especially without significant fracture displacement, translation or evidence of ligamentous disruption on post-injury imaging. We report a case of a patient who sustained a spinal cord transection secondary to an acute type II odontoid fracture from a ground-level fall, without computed tomography radiographic evidence of cord disruption or impingement.

Feasibility and Safety of Cervical Kinematic Magnetic Resonance Imaging in Patients with Cervical Spinal Cord Injury without Fracture and Dislocation

Objective

To evaluate the feasibility and safety of cervical kinematic MRI (KMRI) in patients with cervical spinal cord injury without fracture and dislocation (CSCIWFD).

Methods

This was a single‐institution case‐only study. Patients with CSCIWFD were enrolled in our institution from February 2015 to July 2019. Cervical radiography and CT were performed first to exclude cervical tumors, and major fracture or dislocation. Then neutral static and kinematic (flexion and extension) MRI was performed for patients who met the inclusion criteria under the supervision of a spinal surgeon. Any adverse events during the KMRI examination were recorded. Patients received surgical or conservative treatment based on the imaging results and patients’ own wishes. The American Spinal Injury Association impairment scale (AIS) grade and the Japanese Orthopedic Association (JOA) score were evaluated on admission, before KMRI examination, and after KMRI examination. For the surgical patients, AIS grade and JOA score were evaluated again 1 week after the operation. The JOA scores were compared among different time points using the paired t‐test.

Results

A total of 16 patients (12 men and 4 women, mean age: 51.1 [30–73] years) with CSCIWFD were included in the present study. Clinical symptoms included facial trauma, neck pain, paraplegia, paresthesia, hyperalgesia, sensory loss or weakness below the injury level, and dyskinesia. On admission, AIS grades were B for 2 cases, C for 5, and D for 9. A total of 14 patients underwent neutral, flexion, and extension cervical MRI examination; 2 patients underwent neutral and flexion examination because they could not maintain the position for a prolonged duration. No patient experienced deterioration of neurological function after the examinations. The AIS grades and JOA scores evaluated post‐examination were similar to those evaluated pre‐examination (P > 0.05) and significantly higher than those on admission (P < 0.05). A total of 12 patients received surgical treatment, 11 of whom underwent anterior cervical discectomy and interbody fusion and 1 underwent posterior C3/4 fusion with lateral mass screws. The remaining 4 patients were offered conservative therapy. None of the patients experienced any complications during the perioperative period. The AIS grade did not change in most surgical patients, except that 1 patient changed from grade C to D 1 week after the operation. The JOA score 1 week after surgery was significantly higher than those on admission and around examination for the surgical patients (P < 0.05).

Conclusion

Cervical KMRI is a safe and useful technique for diagnosis of CSCIWFD, which is superior to static cervical MRI for therapeutic decision‐making in patients with CSCIWFD.

Influence of Preoperative Magnetic Resonance Imaging on Surgical Decision Making for Patients with Acute Traumatic Cervical Spinal Cord Injury: A Survey Among Experienced Spine Surgeons

OBJECTIVE

Early decompression after acute spinal cord injury (SCI) is recommended. Acute care is crucial, but optimal management is unclear. The aim of this study was to investigate the role of preoperative magnetic resonance imaging (MRI) in addition to computed tomography (CT) in surgical decision making for acute cervical SCI.

METHODS

All patients with cervical SCI between 2008 and 2016 who had preoperative CT and MRI (n = 63) at the Trauma Center Murnau, Germany, were included. We administered a survey to 10 experienced spine surgeons (5 neurosurgeons, 5 trauma surgeons) regarding the surgical management. First, the surgeons were shown clinical information and CT scans. Two months later, the survey was repeated with additional MRI. Corresponding percentages of change and agreement were obtained for each rater and survey item. Finally, results from both parts of the survey were compared with the definitive treatment option (i.e., real-world decision).

RESULTS

MRI modified surgical timing in a median of 41% of patients (interquartile range 38%-56%). In almost every fifth patient (17%), no surgery would have been indicated with CT alone. The advocated surgical approach was changed in almost half of patients (median 48%, interquartile range 33%-49%). Surgically addressed levels were changed in a median of 57% of patients (interquartile range 56%-60%). MRI led to higher agreement with the real-world decision concerning addressed levels (median 35% vs. 73%), timing (median 51% vs. 57%), and approach (median 44% vs. 65%).

CONCLUSIONS

Preoperative MRI influenced surgical decision making substantially in our cohort and has become a new standard for patients with cervical SCI in our institution if medically possible.

Establishment and verification of a surgical prognostic model for cervical spinal cord injury without radiological abnormality

Some studies have suggested that early surgical treatment can effectively improve the prognosis of cervical spinal cord injury without radiological abnormality, but no research has focused on the development of a prognostic model of cervical spinal cord injury without radiological abnormality. This retrospective analysis included 43 patients with cervical spinal cord injury without radiological abnormality. Seven potential factors were assessed: age, sex, external force strength causing damage, duration of disease, degree of cervical spinal stenosis, Japanese Orthopaedic Association score, and physiological cervical curvature. A model was established using multiple binary logistic regression analysis. The model was evaluated by concordant profiling and the area under the receiver operating characteristic curve. Bootstrapping was used for internal validation. The prognostic model was as follows: logit(P) = -25.4545 + 21.2576VALUE + 1.2160SCORE - 3.4224TIME, where VALUE refers to the Pavlov ratio indicating the extent of cervical spinal stenosis, SCORE refers to the Japanese Orthopaedic Association score (0-17) after the operation, and TIME refers to the disease duration (from injury to operation). The area under the receiver operating characteristic curve for all patients was 0.8941 (95% confidence interval, 0.7930-0.9952). Three factors assessed in the predictive model were associated with patient outcomes: a great extent of cervical stenosis, a poor preoperative neurological status, and a long disease duration. These three factors could worsen patient outcomes. Moreover, the disease prognosis was considered good when logit(P) ≥ -2.5105. Overall, the model displayed a certain clinical value. This study was approved by the Biomedical Ethics Committee of the Second Affiliated Hospital of Xi'an Jiaotong University, China (approval number: 2018063) on May 8, 2018.

Imaging investigations in Spine Trauma: The value of commonly used imaging modalities and emerging imaging modalities

Traumatic spine injuries can be devastating for patients affected and for health care professionals if preventable neurological deterioration occurs. This review discusses the imaging options for the diagnosis of spinal trauma. It lays out when imaging is appropriate and when it is not. It discusses strength and weakness of available imaging modalities. Advanced techniques for spinal injury imaging will be explored. The review concludes with a review of imaging protocols adjusted to clinical circumstances.

Triple trouble: A case of traumatic cervical spinal cord injury in a patient with ossification of posterior longitudinal ligament and disc prolapse

We describe the case of a trauma patient who presented to our emergency department with signs and symptoms suggestive of cervical cord injury. The patient had an underlying ossification of the posterior longitudinal ligament with multiple cervical disc prolapses from C3 to C7. The presence of these two factors increased the impact of the traumatic cervical cord injury. The patient underwent spinal decompression via laminectomy. Unfortunately, his neurological status did not show any significant improvement after the surgery.

Our aim is to highlight the association between ossification of the posterior longitudinal ligament and spinal cord injury in trauma patients.

Clinical Influence of Cervical Spinal Canal Stenosis on Neurological Outcome after Traumatic Cervical Spinal Cord Injury without Major Fracture or Dislocation

Study Design

Retrospective case series.

Purpose

To clarify the influence of cervical spinal canal stenosis (CSCS) on neurological functional recovery after traumatic cervical spinal cord injury (CSCI) without major fracture or dislocation.

Overview of Literature

The biomechanical etiology of traumatic CSCI remains under discussion and its relationship with CSCS is one of the most controversial issues in the clinical management of traumatic CSCI.

Methods

To obtain a relatively uniform background, patients non-surgically treated for an acute C3–4 level CSCI without major fracture or dislocation were selected. We analyzed 58 subjects with traumatic CSCI using T2-weighted mid-sagittal magnetic resonance imaging. The sagittal diameter of the cerebrospinal fluid (CSF) column, degree of canal stenosis, and neurologic outcomes in motor function, including improvement rate, were assessed.

Results

There were no significant relationships between sagittal diameter of the CSF column at the C3–4 segment and their American Spinal Injury Association motor scores at both admission and discharge. Moreover, no significant relationships were observed between the sagittal diameter of the CSF column at the C3–4 segment and their neurological recovery during the following period.

Conclusions

No relationships between pre-existing CSCS and neurological outcomes were evident after traumatic CSCI. These results suggest that decompression surgery might not be recommended for traumatic CSCI without major fracture or dislocation despite pre-existing CSCS.

A model of acute central cervical spinal cord injury syndrome combined with chronic injury in goats

PURPOSE

To develop a large animal model for acute central cervical spinal cord injury syndrome (ACCSCIS.

METHODS

Twenty-four adult male goats were randomized into four groups including group A with acute compression injury, group B with anterior chronic compression, group C as the test group that received anterior chronic compression by screw and acute compression by posterior balloon insertion, and group D as normal controls that received sham surgery. Neurological function (modified Tarlov motor function), CT, MRI, cortical somatosensory evoked potentials (CSEP), and pathological analysis were evaluated. The data were analyzed statistically.

RESULTS

The motor function of the goats in group C was significantly lower than other groups. CSEP before spinal cord compression showed a stable pattern. Spinal cord compression resulted in a gradual decrement in the peak latency and significant increment in the peak amplitude. Cervical spinal canal occupying ratio was significantly lower in group C than the other groups. MRI revealed focal low signal in T1 weighted images and focal high signal in T2 weighted images in group C. Pathological analysis showed more severe lesions in the gray matter than that in the white matter in group C.

CONCLUSIONS

The model well simulated the pathogenesis and resembled the clinical characteristics of ACCSCIS. This model seems to have the potential to contribute to the development of effective therapies for ACCSCIS.

Cervical spinal cord injuries associated with resuscitation from fatal circulatory collapse

Introduction

Fatal cervical spinal cord injury (SCI) associated with collapse of the circulatory and/or respiratory system usually consists of high cervical SCI caused by high-energy trauma. As the elderly population grows, however, the etiology of fatal SCI may be changing. The aim of the present study was to understand the current clinical features of fatal SCI.

Methods

Retrospective analysis was performed on 73 consecutive patients with acute cervical SCI between 2007 and 2013. Fourteen (19%) of them presented in a state of coma due to severe circulatory collapse after cardiac arrest (CA, n = 11) or respiratory arrest (RA, n = 3), and were resuscitated at the scene or hospital. The clinical features and radiological findings of these 14 patients were compared with those of the other 59.

Results

Eleven of the 14 fatal SCI patients were injured by minor traumas. Computed tomography revealed C1-2 fractures or dislocations in 11 patients and subaxial injuries in three patients. Eleven patients showed some kind of ossification of the spinal column ligaments. In a univariate analysis, the predictive factors associated with fatal circulatory collapse were age (P = 0.02), estimated C1/2 injury (P < 0.0001), and complete tetraplegia (P < 0.0001). In a multiple regression model for fatality, the odds ratios (OR) for C1/2 injury and ASIA impairment score (AIS) A were 20.58 (P = 0.006) and 151.97 (P = 0.002).

Conclusions

A state of unconsciousness with fatal circulatory collapse was significantly associated with C1/2 injury and AIS A. Moreover, our data show that fatal SCI can occur due to minor trauma in elderly people.

Subacute T1-low intensity area reflects neurological prognosis for patients with cervical spinal cord injury without major bone injury

STUDY DESIGN

A retrospective imaging and clinical study.

OBJECTIVES

To evaluate the relationship between magnetic resonance imaging (MRI) features and neurological prognosis in patients with traumatic cervical spinal cord injury (CSCI) without major bone injury.

METHODS

A total of 72 patients with CSCI without major bone injury were treated conservatively in our hospital. MRI was performed for all patients at admission and 1 month following injury. We measured the antero-posterior and cranio-caudal diameter of intramedullary intensity changed area with T1-weighted images at the injured segment. Neurological evaluations were performed using the American Spinal Injury Association (ASIA) motor score and the modified Frankel grade at the time of admission and discharge.

RESULTS

There was a significant relationship between the antero-posterior diameter ratio of the T1-weighted low-intensity area on MRI at the subacute stage and the ASIA motor score. The optimal threshold of the T1-weighted low-intensity diameter ratio for predicting the patient's ability to walk with or without assistance at discharge was determined to be 46%. Moreover, 96.8% of the patients with <50% T1-weighted low-intensity area recovered to walk with or without a cane at discharge.

CONCLUSION

The T1-low intensity area may be an important predictive factor for the neurological recovery of CSCI without major bone injury.

Prognostic factors for surgical outcome in spinal cord injury associated with ossification of the posterior longitudinal ligament (OPLL)

BACKGROUND

Ossification of the posterior longitudinal ligament (OPLL) may increase the risk of spinal cord injury (SCI) with various neurological deficits after minor trauma. However, few studies have investigated the influence of OPLL on neurological outcome after acute cord injury. We examined whether severe spinal canal stenosis caused by OPLL affects neurological outcome after SCI based on intramedullary signal intensity (SI) changes on magnetic resonance imaging (MRI).

METHODS

From June 2006 to July 2013, we treated 246 patients with cervical cord injury. Fifty-one (20.7%) patients had ventral cord compression due to OPLL without any bony fractures. Among them, 38 patients (34 men, mean age 62.7 years) underwent cervical laminoplasty (8) and cervical decompression and fixation (30). The neurologic assessments were performed in patients who had 1-year follow-up, and the mean follow-up period was 42.2 months. OPLL type, cause of injury, cervical sagittal angle, cervical spine stenosis, cord compression ratio (space available for the spinal cord (SAC)), and grade of intramedullary SI (grade 0, none; grade 1, light; grade 2, intense T2WI) were assessed.

RESULTS

Mean American Spinal Injury Association (ASIA) motor score at admission was 38.4 ± 21.9 (range, 2-70) and improved to 67.7 ± 19.1 (range, 8-94) at last follow-up (p < 0.05). Mean recovery rate of the motor score was 55.8 ± 19.9%. Five patients had SI grade 0, 20 patients had SI grade 1, and 13 patients had SI grade 2. Among the variables tested, age, initial ASIA motor grade, intramedullary SI grade, and SAC were significantly related to neurological outcome. However, initial cervical alignment, canal diameter, length of SI, time interval between injury and operation, and OPLL type had no significant effect on neurological outcome.

CONCLUSIONS

Preoperative neurological status, cord compression ratio, and SI grade are related to neurological outcome in patients with SCI associated with OPLL. The better the preoperative neurological status, the more favorable the neurological outcome after surgery. A higher SI grade on preoperative T2WI was negatively related to neurological outcome. Therefore, the severity of SI change, cord compression ratio, and preoperative neurological status can be regarded as significant prognostic factors in patients with SCI associated with OPLL.

Does intramedullary signal intensity on MRI affect the surgical outcomes of patients with ossification of posterior longitudinal ligament?

Objectives

Patients with cervical ossification of posterior longitudinal ligament (OPLL) are susceptible to cord injury, which often develops into myelopathic symptoms. However, little is known regarding the prognostic factors that are involved in minor trauma. We evaluated the relationship between minor trauma and neurological outcome of OPLL and investigated the prognostic factors with a focus on compressive factors and intramedullary signal intensity (SI).

Methods

A total of 74 patients with cervical myelopathy caused by OPLL at more than three-levels were treated with posterior decompression surgeries. We surveyed the space available for spinal cord (SAC), the severity of SI change on T2-weighted image, and diabetes mellitus (DM). The neurological outcome using Japanese Orthopedic Association (JOA) scale was assessed at admission and at 12-month follow-up.

Results

Among the variables tested, preoperative JOA score, severity of intramedullary SI, SAC, and DM were significantly related to neurological outcome. The mean preoperative JOA were 11.3±1.9 for the 41 patients who did not have histories of trauma and 8.0±3.1 for the 33 patients who had suffered minor traumas (p<0.05). However, there were no significant differences in the recovery ratios between those two groups.

Conclusions

Initial neurological status and high intramedullary SI in the preoperative phase were related to poorer postoperative outcomes. Moreover, the patients with no histories of DM and larger SACs exhibited better improvement than did the patients with DM and smaller SACs. Although the initial JOA scores were worse for the minor trauma patients than did those who had no trauma prior to surgery, minor trauma exerted no direct effects on the surgical outcomes.

Clinical relationship between cervical spinal canal stenosis and traumatic cervical spinal cord injury without major fracture or dislocation

PURPOSE

The purpose of the study was to evaluate the clinical relationship between cervical spinal canal stenosis (CSCS) and incidence of traumatic cervical spinal cord injury (CSCI) without major fracture or dislocation, and to discuss the clinical management of traumatic CSCI.

METHODS

Forty-seven patients with traumatic CSCI without major fracture or dislocation (30 out of 47 subjects; 63.83 %, had an injury at the C3-4 segment) and 607 healthy volunteers were measured the sagittal cerebrospinal fluid (CSF) column diameter at five pedicle and five intervertebral disc levels using T2-weighted midsagittal magnetic resonance imaging. We defined the sagittal CSF column diameter of less than 8 mm as CSCS based on the previous paper. We evaluated the relative and absolute risks for the incidence of traumatic CSCI related with CSCS.

RESULTS

Using data from the Spinal Injury Network of Fukuoka, Japan, the relative risk for the incidence of traumatic CSCI at the C3-4 segment with CSCS was calculated as 124.5:1. Moreover, the absolute risk for the incidence of traumatic CSCI at the C3-4 segment with CSCS was calculated as 0.00017.

CONCLUSIONS

In our results, the relative risk for the incidence of traumatic CSCI with CSCS was 124.5 times higher than that for the incidence without CSCS. However, only 0.017 % of subjects with CSCS may be able to avoid developing traumatic CSCI if they undergo decompression surgery before trauma. Our results suggest that prophylactic surgical management for CSCS might not significantly affect the incidence of traumatic CSCI.

Soft-tissue damage and segmental instability in adult patients with cervical spinal cord injury without major bone injury

STUDY DESIGN

A retrospective imaging and clinical study.

OBJECTIVE

To evaluate the extraneural soft-tissue damage and its clinical relevance in patients with traumatic cervical spinal cord injury (SCI) without major bone injury.

SUMMARY OF BACKGROUND DATA

To date, various kinds of cervical discoligamentous injuries have been demonstrated on magnetic resonance images in patients with SCI without bony injury. However, it has not been clear whether these magnetic resonance imaging abnormalities are actually related to spinal segmental instability and the patients' neurological status.

METHODS

Eighty-eight adult patients with acute traumatic cervical SCI without major bone injury were examined by flexion-extension lateral radiographs and magnetic resonance images within 2 days after trauma. We excluded patients with flexion recoil injury; therefore, most of the patients included were considered to have sustained a hyperextension injury. Instability of the injured cervical segment was defined when there was more than 3.5-mm posterior translation and/or more than a 11° difference in the intervertebral angle between the site of interest and adjacent segments. The neurological status was evaluated according to the American Spinal Injury Association motor score.

RESULTS

On magnetic resonance images, the damage to the anterior longitudinal ligament and intervertebral disc were apparent in 44 and 37 patients, respectively. Various degrees of prevertebral fluid collection (prevertebral hyperintensity) were demonstrated in 76 patients. These magnetic resonance imaging abnormalities were significantly associated with initial cervical segmental instability as judged by flexion-extension radiographs. Interestingly, the American Spinal Injury Association motor score had a significant association with either magnetic resonance imaging abnormalities or segmental instability but not with the cervical canal diameter.

CONCLUSION

A considerable proportion of the patients with traumatic cervical SCI without major bone injury were shown to have various types of soft-tissue damage associated with cervical segmental instability at the early stages of the injury. The severity of paralysis greatly depended on these discoligamentous injuries.

Alterations in mouse hypothalamic adipokine gene expression and leptin signaling following chronic spinal cord injury and with advanced age

Chronic spinal cord injury (SCI) results in an accelerated trajectory of several cardiovascular disease (CVD) risk factors and related aging characteristics, however the molecular mechanisms that are activated have not been explored. Adipokines and leptin signaling are known to play a critical role in neuro-endocrine regulation of energy metabolism, and are now implicated in central inflammatory processes associated with CVD. Here, we examine hypothalamic adipokine gene expression and leptin signaling in response to chronic spinal cord injury and with advanced age. We demonstrate significant changes in fasting-induced adipose factor (FIAF), resistin (Rstn), long-form leptin receptor (LepRb) and suppressor of cytokine-3 (SOCS3) gene expression following chronic SCI and with advanced age. LepRb and Jak2/stat3 signaling is significantly decreased and the leptin signaling inhibitor SOCS3 is significantly elevated with chronic SCI and advanced age. In addition, we investigate endoplasmic reticulum (ER) stress and activation of the uncoupled protein response (UPR) as a biological hallmark of leptin resistance. We observe the activation of the ER stress/UPR proteins IRE1, PERK, and eIF2alpha, demonstrating leptin resistance in chronic SCI and with advanced age. These findings provide evidence for adipokine-mediated inflammatory responses and leptin resistance as contributing to neuro-endocrine dysfunction and CVD risk following SCI and with advanced age. Understanding the underlying mechanisms contributing to SCI and age related CVD may provide insight that will help direct specific therapeutic interventions.

Surgical management of cervical cord injury with ossification of the cervical posterior longitudinal ligament

OBJECTIVE

To identify an appropriate surgical approach for the management of cervical cord injury with ossification of the posterior longitudinal ligament.

METHODS

A retrospective study of 25 cases of cervical cord injury with ossification of the posterior longitudinal ligament was performed. Two cases were classified as Frankel grade A, three as grade B, fourteen as grade C, and six as grade D. Treatment procedures consisted of anterior decompression with instrumentation (twelve patients), posterior decompression (eight patients), and combined anterior and posterior decompression (five patients).

RESULTS

There were no iatrogenic injuries of great vessels, trachea, esophagus or spinal cord. All patients were followed up for 15-86 months (average, 38.3 months). All segment with anterior fixation attained solid fusion, without implants loosening or breakage. No reclosed open-door was found after posterior laminoplasty. Twenty-one patients improved by one to two Frankel grades. The patients with complete spinal cord injury achieved no neurologic recovery, but did experience relief of upper limb pain or numbness.

CONCLUSION

The surgical outcomes of cervical cord injury with ossification of the posterior longitudinal ligament were satisfactory. It is important to select a suitable surgical approach according to the findings on radiological imaging and the clinical characteristics and general condition of the patients.

Clinical analysis of spinal cord injury with or without cervical ossification of the posterior longitudinal ligament, spondylosis, and canal stenosis in elderly head injury patients

Patients with degenerative diseases of the cervical spine, such as ossification of the posterior longitudinal ligament, spondylosis, and canal stenosis, sometimes present with acute spinal cord injury caused by minor trauma. However, the relative risk of cervical cord injury with these diseases is unknown. The clinical and radiological features of 94 elderly patients with head injury, 57 men and 37 women aged from 65 to 98 years (mean 76.6 years), were retrospectively analyzed to assess the association of spinal cord injury with degenerative cervical diseases. Degenerative cervical diseases were present in 25 patients, and spinal cord injury was more common in the patients with degenerative diseases (11/25 patients) than in the patients without such diseases (3/69 patients; relative risk = 10.2). The incidence of degenerative cervical diseases seems to be increasing in Japan because life expectancy has increased and the elderly are a rapidly growing part of the population. A fall while walking or cycling is a common mechanism of head injury and/or cervical cord injury in the elderly. To decrease the occurrence of cervical myelopathy, prevention by increasing social awareness and avoiding traffic accidents and falls is important.

Advances in imaging of vertebral and spinal cord injury

BACKGROUND/OBJECTIVES

Imaging technology is an important part of the diagnosis and management of spinal trauma. Indications and findings in post-traumatic imaging of the vertebral column and spinal cord are reviewed.

METHODS

An extensive literature review was performed on the imaging of vertebral and spinal cord injury. Relevant images from a Level I trauma center were included as examples.

RESULTS

Imaging plays an important role in the evaluation of acute and chronic spinal injury. Spinal cord and soft-tissue injuries are best evaluated by magnetic resonance imaging (MRI), whereas spinal fractures are better characterized by computed tomography (CT). Vascular injuries can be evaluated using CT or MR angiography.

CONCLUSIONS

Imaging using CT and MRI is essential in the management of spinal cord injuries, both in the acute and in the chronic settings. MRI shows the status of ligamentous integrity and visualizes internal derangement of the spinal cord. Vascular compromise can be diagnosed by MR and CT angiography. Plain radiography now has a more limited, adjunctive role, and the need for higher risk myelography has been minimized.

[The value of dynamic cervical MRI in management of selected patients presenting traumatic cervical cord injury]

OBJECTIVE

The purpose of this report is to describe our experience with dynamic cervical MRI for detection of cervical spinal cord instability in patients presenting spinal cord trauma without fracture or dislocation of the spinal column.

MATERIAL AND METHODS

Since January 2000 a total of 95 patients presenting spinal cord trauma have been treated in our department. All patients underwent MRI for diagnostic work-up. Dynamic MRI was performed if spinal cord instability was suspected. Whenever possible, high-quality plain radiography dynamic views were obtained (coma, severe deficit, study of the cervicothoracic junction).

RESULTS

Dynamic MRI allowed diagnosis of spinal cord instability in 6 patients with a mean age of 65 years (range, 45 to 75). Instability occurred during extension in 4 patients and during flexion and extension in one case. In the remaining case instability was associated with herniation of a cervical disc due to a severe cervical sprain. All 6 patients underwent early surgical stabilization that allowed improvement in-hospital patient care and quick transfer to rehabilitation centers.

CONCLUSION

Dynamic MRI can be a useful tool to detect unstable spinal cord instability in some patients presenting noncompressive spinal cord injuries.

Epidemiology of traumatic spinal cord injury in Canada

STUDY DESIGN

Retrospective review.

OBJECTIVE

To describe the incidence, clinical features, and treatment of traumatic spinal cord injury (SCI) treated at a Canadian tertiary care center.

SUMMARY OF BACKGROUND DATA

Understanding the current epidemiology of acute traumatic SCI is essential for public resource allocation and primary prevention. Recent reports suggest that the mean age of patients with SCI may be increasing.

METHODS

We retrospectively reviewed hospital records on all patients with traumatic SCI between January 1997 and June 2001 (n = 151). Variables assessed included age, gender, length of hospitalization, type and mechanism of injury, associated spinal fractures, neurologic deficit, and treatment.

RESULTS

Annual age-adjusted incidence rates were 42.4 per million for adults aged 15-64 years, and 51.4 per million for those 65 years and older. Motor vehicle accidents accounted for 35% of SCI. Falls were responsible for 63% of SCI among patients older than 65 years and for 31% of injuries overall. Cervical SCI was most common, particularly in the elderly, and was associated with fracture in only 56% of cases. Thoracic and lumbar SCI were associated with spinal fractures in 100% and 85% of cases, respectively. In-hospital mortality was 8%. Mortality was significantly higher among the elderly. Treatment of thoracic and lumbar fractures associated with SCI was predominantly surgical, whereas cervical fractures were equally likely to be treated with external immobilization alone or with surgery.

CONCLUSION

A large proportion of injuries was seen among older adults, predominantly as a result of falls. Prevention programs should expand their focus to include home safety and avoidance of falls in the elderly.

Assessing cervical spine stability in obtunded blunt trauma patients: review of medical literature

PURPOSE

To review the current medical literature on dynamic fluoroscopic and magnetic resonance (MR) imaging assessment of cervical spine stability in obtunded patients who sustained blunt trauma.

MATERIALS AND METHODS

The English-language literature within the Swetswise and Medline databases was searched for articles describing dynamic fluoroscopic or MR imaging assessment of cervical spine stability in patients who sustained blunt trauma. Patients with fractures or radiographic signs of injury were excluded. The frequencies of purely ligamentous injuries, injuries requiring immobilization, and other clinically important nonligamentous abnormalities were determined.

RESULTS

The frequency of isolated cervical ligamentous injuries diagnosed with dynamic fluoroscopy, as reported in the literature, was 0.9% (11 of 1166 patients), whereas the reported frequency of these injuries diagnosed with MR imaging was 22.7% (125 of 550 patients). All injuries diagnosed with dynamic fluoroscopy and 101 (80.8%) of those diagnosed with MR imaging required continued cervical immobilization. Six (60%) of 10 injuries diagnosed with dynamic fluoroscopy and seven (5.6%) of 125 injuries diagnosed with MR imaging required surgical or halo stabilization. Five (2.5%) of the 200 obtunded patients assessed with MR imaging and six (0.5%) of the 1166 obtunded patients evaluated with dynamic fluoroscopy required surgery.

CONCLUSION

Review of the current medical literature provided no clear evidence of the superiority of either MR imaging or dynamic fluoroscopy in the diagnosis of unstable ligamentous injury, although other relative advantages of MR imaging indicate that it is preferred for assessing cervical spine stability in obtunded blunt trauma patients.

Spinal canal size in ossification of the posterior longitudinal ligament of the cervical spine

BACKGROUND

The size of the spinal canal is a factor that contributes to the neurologic deficits associated with cervical ossification of the posterior longitudinal ligament (OPLL).

METHODS

Bone-window computed tomography (CT) examinations of the cervical spine in 64 patients with cervical OPLL were reviewed. Forty-two patients underwent surgical treatment (anterior decompression: 16 patients, posterior decompression: 26 patients). The remaining 22 patients were managed conservatively. Selection of the surgical approach, anterior or posterior, was based on the longitudinal extent of cord compression.

RESULTS

The mean developmental size of the spinal canal in the posterior decompression group (10.7 mm at C4) was significantly smaller than the other 2 groups. The spinal canal was narrowed by OPLL to 2.9 to 10.0 mm. The proportion of the patients showing motor deficits of the lower extremities significantly increased when the sagittal canal diameter was narrowed to less than 8 mm.

CONCLUSIONS

This study demonstrates critical values of CT-determined spinal canal stenosis. Developmental size of the spinal canal and the residual anterior-posterior canal diameters resulting from OPLL spinal cord compression are important factors influencing clinical management and the neurologic state.