Flexion/Extension Cervical Magnetic Resonance Imaging: A Potentially Useful Tool for Decision-Making in Patients with Symptomatic Degenerative Cervical Spine.

OBJECTIVE: To evaluate the reliability and usefulness of cervical flexion/extension magnetic resonance imaging (MRI) as a tool for decision-making regarding treatment of symptomatic cervical spondylosis. METHODS: We prospectively collected demographic, clinical, and flexion/neutral/extension MRI data for consecutive 24 patients who had presented with symptomatic cervical degenerative disease. From the survey responses, we analyzed the agreement between clinical interpretation and judgment when neutral MRI (nMRI) versus flexion/extension MRI (fMRI/eMRI) had been provided. Additionally, the mean cervical canal diameter (MCCD), as measured by 2 independent radiologists, was tested for intra- and interobserver reliability. The differences in MCCD between nMRI, fMRI, and eMRI and the correlation with the qualitative assessment by spine surgeons were also evaluated. RESULTS: Using nMRI only, 16.7%-33.3% of the surgical candidates were missed. Neurosurgeons were significantly more likely to use a posterior approach and instrumentation when fMRI/eMRI studies were available compared with nMRI studies alone. More levels had undergone surgery when the providers had been presented with the fMRI/eMRI studies. The raters expressed a preference for the use of fMRI/eMRI in their future practice. The MCCD was significantly different when measured on the nMRI studies compared with the fMRI/eMRI studies and correlated with the qualitative assessments. CONCLUSIONS: Flexion/extension MRI studies were useful for assessing patients with cervical degenerative spine disorders regarding the surgical indication, direction of the approach, and use of multilevel instrumentation, especially for patients with early cervical myelopathy.

Transvenous Embolization of Brain Arteriovenous Malformations: Up-to-Date Meta-Analysis.

AIM: To conduct an up-to-date meta-analysis to assess the success and complication rates of transvenous embolization (TVE) of brain arteriovenous malformations (BAVMs), and to determine its efficacy and safety. MATERIAL AND METHODS: Relevant and potentially relevant studies from 1982 to February 2021 were searched; after which those that satisfied our eligibility criteria and reported the main outcomes (endovascular occlusion and complication rates) were included. RESULTS: Ultimately seven studies were selected. In total, 154 patients were comprehensively reviewed for BAVMs characteristics and endovascular TVE techniques. The weighted mean rate of immediate endovascular total occlusion, overall technical complication, and overall good functional outcome (mRs < 2) were 93% (95% confidence intervals (CI), 89.1%?96.9%, I2 = 0%, p=0.487), 10.5% (95% CI, 4.3%?16.6%, I2 = 30.8%, p=0.193), and 90.9% (95% CI, 85.3%?96.6%, I2 = 26.6%, p=0.241), respectively. CONCLUSION: TVE for BAVMs was found to be generally safe and effective in certain selected patients. However, the complementary role of TAE to TVE as a definitive endovascular treatment for BAVMs cannot be separated. More studies regarding this role need to be conducted.

Recent Advances in the Regenerative Approaches for Traumatic Spinal Cord Injury: Materials Perspective.

Spinal cord injury (SCI) is a devastating health condition that may lead to permanent disabilities and death. Understanding the pathophysiological perspectives of traumatic SCI is essential to define mechanisms that can help in designing recovery strategies. Since central nervous system tissues are notorious for their deficient ability to heal, efforts have been made to identify solutions to aid in restoration of the spinal cord tissues and thus its function. The two main approaches proposed to address this issue are neuroprotection and neuro-regeneration. Neuroprotection involves administering drugs to restore the injured microenvironment to normal after SCI. As for the neuro-regeneration approach, it focuses on axonal sprouting for functional recovery of the injured neural tissues and damaged axons. Despite the progress made in the field, neural regeneration treatment after SCI is still unsatisfactory owing to the disorganized way of axonal growth and extension. Nanomedicine and tissue engineering are considered promising therapeutic approaches that enhance axonal growth and directionality through implanting or injecting of the biomaterial scaffolds. One of these recent approaches is nanofibrous scaffolds that are used to provide physical support to maintain directional axonal growth in the lesion site. Furthermore, these preferable tissue-engineered substrates can afford axonal regeneration by mimicking the extracellular matrix of the neural tissues in terms of biological, chemical, and architectural characteristics. In this review, we discuss the regenerative approach using nanofibrous scaffolds with a focus on their fabrication methods and their properties that define their functionality performed to heal the neural tissue efficiently.

Candidates for Percutaneous Screw Fixation Without Fusion in Thoracolumbar Fractures: A Retrospective Matched Cohort Study.

STUDY DESIGN: Retrospective matched cohort study. OBJECTIVES: Identifying candidates for isolated percutaneous screw fixation (PSF) in thoracolumbar fractures based on Thoracolumbar Injury Classification and Severity (TLICS) score. METHODS: Patients underwent PSF were split into 3 TLICS-score categories, then matched with groups having similar scores managed either non-operatively or via open screw fixation (OSF). Each category was assessed for corrective power and loss of correction by comparing initial and 1-year Cobb angles as well as Oswestry Disability Index and rates of fracture healing at 1 year. RESULTS: A total of 102 patients (40 females) with age range 19 to 51 years, were admitted 1 to 25 hours following trauma. Each of TLISC categories consisted of matched treatment groups for comparison. In TLICS-3 fractures (2 treatment groups, n = 12 each), PSF showed similar outcomes but longer time to ambulation and length of stay (LOS) compared with nonoperative management. In TLICS-4 fractures (3 treatment groups, n = 18 each), PSF showed comparable corrective power and outcomes as OSF but was better in terms of operative time, blood loss, time to ambulation, LOS, and cosmesis. Despite higher LOS when compared with nonoperative cases, PSF showed superior radiologic and functional outcomes. In TLICS-5 fractures (2 treatment groups, n = 12 each), PSF showed shorter admissions and time to ambulation but lower corrective power, functional recovery, and tendency to lower healing rates. CONCLUSIONS: Isolated PSF is a valid choice in managing TLICS-4 thoracolumbar fractures; however, it did not surpass conventional methods in TLICS-3 or TLICS-5 fracture types. Further studies are needed before the generalization of findings.

Biomarkers in Spinal Cord Injury: Prognostic Insights and Future Potentials.

Spinal Cord Injury (SCI) is a major challenge in Neurotrauma research. Complex pathophysiological processes take place immediately after the injury and later on as the chronic injury develops. Moreover, SCI is usually accompanied by traumatic injuries because the most common modality of injury is road traffic accidents and falls. Patients develop significant permanent neurological deficits that depend on the extent and the location of the injury itself and in time they develop further neurological and body changes that may risk their mere survival. In our review, we explored the recent updates with regards to SCI biomarkers. We observed two methods that may lead to the appearance of biomarkers for SCI. First, during the first few weeks following the injury the Blood Spinal Cord Barrier (BSCB) disruption that releases several neurologic structure components from the injured tissue. These components find their way to Cerebrospinal Fluid (CSF) and the systemic circulation. Also, as the injury develops several components of the pathological process are expressed or released such as in neuroinflammation, apoptosis, reactive oxygen species, and excitotoxicity sequences. Therefore, there is a growing interest in examining any correlations between these components and the degrees or the outcomes of the injury. Additionally, some of the candidate biomarkers are theorized to track the progressive changes of SCI which offers an insight on the patients' prognoses, potential-treatments-outcomes assessment, and monitoring the progression of the complications of chronic SCI such as Pressure Ulcers and urinary dysfunction. An extensive literature review was performed covering literature, published in English, until February 2018 using the Medline/PubMed database. Experimental and human studies were included and titles, PMID, publication year, authors, biomarkers studies, the method of validation, relationship to SCI pathophysiology, and concluded correlation were reported. Potential SCI biomarkers need further validation using clinical studies. The selection of the appropriate biomarker group should be made based on the stage of the injuries, the accompanying trauma and with regards to any surgical, or medical interference that might have been done. Additionally, we suggest testing multiple biomarkers related to the several pathological changes coinciding to offer a more precise prediction of the outcome.

Epidemiological Characteristics of Traumatic Spinal Cord Injury (TSCI) in the Middle-East and North-Africa (MENA) Region: A Systematic Review and Meta-Analysis.

OBJECTIVE: To systematically search the literature and to summarize current evidence pertaining to the epidemiology of SCI in the MENA region incidence, gender, age, type of the injury and etiology of the injury. METHODS: Embase, PubMed, Scopus, Web of Science and EBSCOhost were systematically searched from their dates of inception till July 2017 for English and non-English language articles. Also, regional databases were searched. Data were extracted from eligible articles and pooled under the random effect model using R. References of the included articles were also screened for potentially relevant studies. RESULTS: We identified 29 articles from seven countries in the MENA region (Turkey, Iran, Saudi Arabia, Egypt, Jordan, Kuwait and Qatar). The mean age of the cases at time of injury was 31.32 (95% CI: 28.74-33.91). The random pooled annual incidence of TSCI per million was 23.24 (95% CI: 5.64-49.21). Pooled proportion of male gender was 77% (95% CI 73-80%) of the cases. Complete paraplegia was the most common type of injury. Thoracic level injury predominated. Also, the most commonly affected age group was 20-29 then 30-39. Motor vehicle accidents were found to be the leading cause of injury, then falls, gunshot, violence and sports. Further meta-regression analysis showed no association between age and etiology of the injury. CONCLUSION: This review shows lack of evidence about SCI in most countries of the MENA region. More epidemiological studies are needed.

Adjacent Level Ligamentous Injury Associated with Traumatic Cervical Spine Fractures: Indications for Imaging and Implications for Treatment.

BACKGROUND: Magnetic resonance imaging (MRI) is a vital tool for detection of soft tissue injury (STI) after cervical spine injury (CSI). However, high cost, prolonged imaging time, and limited use in hemodynamically unstable patients necessitates that the utility of MRI in all patients with CSI be scrutinized. METHODS: A retrospective review was performed of all patients treated for a CSI at a Level I trauma center between 2005 and 2010. Patient demographics, fracture characteristics, and associated STIs were collected. STIs were classified further into same level ligamentous injury, adjacent level ligamentous injury (ALLI), cord contusion, and traumatic herniated disc. ALLI was defined as anterior or posterior longitudinal ligament, ligamentum flavum, or supraspinous or interspinous ligamentous injury. RESULTS: MRI was performed in 240 of 787 patients. Evidence of STI was identified in 54.6%. ALLI was the most common STI (80 of 240 patients); these injuries were subdivided into above, below, or both above and below the concurrent fracture level. Patients with ALLI were significantly more likely to have injured C3 (P < 0.01) and C5 (P < 0.03) levels, association with widened disc space (P = 0.03), and multiple CSIs (P = 0.008). The whole ALLI was included in the fixation strategy in 100% of patients with ALLI only above the concurrent fracture level and 87% of patients with ALLI only below the concurrent fracture level. CONCLUSIONS: MRI detected an associated STI in about 55% of patients who underwent imaging. Injuries involving multiple fractured cervical levels, fractures at C3 and C5, and widened disc space should raise the treating physician's level of suspicion for ALLI. Our data show that treatment directed by MRI findings in select cases has substantial value.

Transcranial magnetic stimulation after spinal cord injury.

OBJECTIVE: To review the basic principles and techniques of transcranial magnetic stimulation (TMS) and provide information and evidence regarding its applications in spinal cord injury clinical rehabilitation. METHODS: A review of the available current and historical literature regarding TMS was conducted, and a discussion of its potential use in spinal cord injury rehabilitation is presented. RESULTS: TMS provides reliable information about the functional integrity and conduction properties of the corticospinal tracts and motor control in the diagnostic and prognostic assessment of various neurological disorders. It allows one to follow the evolution of motor control and to evaluate the effects of different therapeutic procedures. Motor-evoked potentials can be useful in follow-up evaluation of motor function during treatment and rehabilitation, specifically in patients with spinal cord injury and stroke. Although studies regarding somatomotor functional recovery after spinal cord injury have shown promise, more trials are required to provide strong and substantial evidence. CONCLUSIONS: TMS is a promising noninvasive tool for the treatment of spasticity, neuropathic pain, and somatomotor deficit after spinal cord injury. Further investigation is needed to demonstrate whether different protocols and applications of stimulation, as well as alternative cortical sites of stimulation, may induce more pronounced and beneficial clinical effects.

Potential role of growth factors in the management of spinal cord injury.

OBJECTIVE: To review central nervous system growth factors and their therapeutic potential and clinical translation into spinal cord injury (SCI), as well as the challenges that have been encountered during clinical development. METHODS: A systemic review of the available current and historical literature regarding central nervous system growth factors and clinical trials regarding their use in spinal cord injury was conducted. RESULTS: The effectiveness of administering growth factors as a potential therapeutic strategy for SCI has been tested with the use of brain-derived neurotrophic factor, glial cell-derived neurotrophic factor, neurotrophin 3, and neurotrophin-4/5. Delivery of growth factors to injured SC has been tested by numerous methods. Unfortunately, most of clinical trials at this time are uncontrolled and have questionable results because of lack of efficacy and/or unacceptable side effects. CONCLUSIONS: There is promise in the use of specific growth factors therapeutically for SCI. However, more studies involving neuronal regeneration and functional recovery are needed, as well the development of delivery methods that allow sufficient quantity of growth factors while restricting their distribution to target sites.

Reprint of "Drawing breath without the command of effectors: the control of respiration following spinal cord injury".

The maintenance of blood gas and pH homeostasis is essential to life. As such breathing, and the mechanisms which control ventilation, must be tightly regulated yet highly plastic and dynamic. However, injury to the spinal cord prevents the medullary areas which control respiration from connecting to respiratory effectors and feedback mechanisms below the level of the lesion. This trauma typically leads to severe and permanent functional deficits in the respiratory motor system. However, endogenous mechanisms of plasticity occur following spinal cord injury to facilitate respiration and help recover pulmonary ventilation. These mechanisms include the activation of spared or latent pathways, endogenous sprouting or synaptogenesis, and the possible formation of new respiratory control centres. Acting in combination, these processes provide a means to facilitate respiratory support following spinal cord trauma. However, they are by no means sufficient to return pulmonary function to pre-injury levels. A major challenge in the study of spinal cord injury is to understand and enhance the systems of endogenous plasticity which arise to facilitate respiration to mediate effective treatments for pulmonary dysfunction.

Drawing breath without the command of effectors: the control of respiration following spinal cord injury.

The maintenance of blood gas and pH homeostasis is essential to life. As such breathing, and the mechanisms which control ventilation, must be tightly regulated yet highly plastic and dynamic. However, injury to the spinal cord prevents the medullary areas which control respiration from connecting to respiratory effectors and feedback mechanisms below the level of the lesion. This trauma typically leads to severe and permanent functional deficits in the respiratory motor system. However, endogenous mechanisms of plasticity occur following spinal cord injury to facilitate respiration and help recover pulmonary ventilation. These mechanisms include the activation of spared or latent pathways, endogenous sprouting or synaptogenesis, and the possible formation of new respiratory control centres. Acting in combination, these processes provide a means to facilitate respiratory support following spinal cord trauma. However, they are by no means sufficient to return pulmonary function to pre-injury levels. A major challenge in the study of spinal cord injury is to understand and enhance the systems of endogenous plasticity which arise to facilitate respiration to mediate effective treatments for pulmonary dysfunction.

Surgical versus nonsurgical treatment of subaxial cervical pedicle fractures.

BACKGROUND: Pedicle fractures in the cervical spine are common. They may occur in isolation or in combination with other concomitant fractures. Multiple classification systems have been introduced to provide a clinical framework when approaching these types of fractures; however, these systems do not provide guidelines for optimal treatment. Data regarding decision making are limited. Conservative treatment with orthoses may result in subluxation and instability requiring further treatment. Surgery may not be required in all instances because many of these injuries may heal without surgical intervention. METHODS: All cases of cervical fractures treated at a single institution over a 5-year period were retrospectively reviewed. Cases with pedicle fractures were further evaluated, and 40 cases managed either with or without surgery were identified. Data on presenting history, neurologic examination, imaging findings, comorbidity, method of treatment, complication rate, and length of hospital stay were collected. Fractures were classified based on computed tomography scans. Data on associated injuries were also collected. Fusion rate and fracture displacement were assessed by plain radiographs and computed tomography scans at follow-up. Follow-up time points included 2, 6, and 12 weeks and 6 months after injury. Primary outcome was fracture healing regardless of modality in the absence of progressive deformity (i.e., listhesis, kyphosis) and need for further surgery. RESULTS: Conservative therapy was administered to 26 patients, and 14 patients underwent surgery. There were no statistically significant differences between the 2 groups in terms of total levels injured (P = 0.9) or injury severity score (P = 0.5). Patients who presented with intact neurologic status were more likely to be treated conservatively (88% vs. 29%; P = 0.0004), whereas patients presenting with spinal cord injuries were more likely to undergo surgical fixation (35% vs. 0%; P = 0.0004). Length of hospital stay trended toward being significantly greater in patients who underwent surgery (10.6 days vs. 5.5 days; P = 0.07). According to our classification system, the most common fracture type was single line horizontal fracture occurring in 68% (27 of 40 cases). Vertical split pedicle fracture occurred in 28% (11 of 40 cases), and double line horizontal fracture occurred in 5% (2 of 40 cases). Posttreatment progressive listhesis was significantly higher in patients who were treated conservatively (31% vs. 0%; P = 0.03), especially when associated with comminuted lateral mass or subluxation or both. CONCLUSIONS: This study describes and classifies unique cervical pedicle fractures and associated injuries. Our findings suggest that surgical treatment results in definitive stability for these injuries compared with conservative therapy, particularly for pedicle fractures associated with comminuted lateral mass or initially displaced fractures. However, nondisplaced vertical split pedicle fractures and isolated single line horizontal fractures may be treated nonsurgically without occurrence of further instability. A larger prospective study is required to confirm these findings.

The role of the crossed phrenic pathway after cervical contusion injury and a new model to evaluate therapeutic interventions.

More than 50% of all spinal cord injury (SCI) cases are at the cervical level and usually result in the impaired ability to breathe. This is caused by damage to descending bulbospinal inspiratory tracts and the phrenic motor neurons which innervate the diaphragm. Most investigations have utilized a lateral C2 hemisection model of cervical SCI to study the resulting respiratory motor deficits and potential therapies. However, recent studies have emerged which incorporate experimental contusion injuries at the cervical level of the spinal cord to more closely reflect the type of trauma encountered in humans. Nonetheless, a common deficit observed in these contused animals is the inability to increase diaphragm motor activity in the face of respiratory challenge. In this report we tested the hypothesis that, following cervical contusion, all remaining tracts to the phrenic nucleus are active, including the crossed phrenic pathway (CPP). Additionally, we investigated the potential function these spared tracts might possess after injury. We find that, following a lateral C3/4 contusion injury, not all remaining pathways are actively exciting downstream phrenic motor neurons. However, removing some of these pathways through contralateral hemisection results in a cessation of all activity ipsilateral to the contusion. This suggests an important modulatory role for these pathways. Additionally, we conclude that this dual injury, hemi-contusion and post contra-hemisection, is a more effective and relevant model of cervical SCI as it results in a more direct compromise of diaphragmatic motor activity. This model can thus be used to test potential therapies with greater accuracy and clinical relevance than cervical contusion models currently allow.

Bilateral Pedicle Screw Fixation versus Unilateral Pedicle and Contralateral Facet Screws for Minimally Invasive Transforaminal Lumbar Interbody Fusion: Clinical Outcomes and Cost Analysis.

Study Design Retrospective clinical study. Objectives Recent biomechanical studies have shown no differences in stiffness or range of motion following minimally invasive (MIS) transforaminal lumbar interbody fusion (TLIF) between unilateral pedicle and contralateral facet screw (UPFS) and bilateral pedicle screw (BPS) constructs. No studies have compared these two constructs based upon clinical outcomes. Methods Twenty-six consecutive patients who had single-level MIS TLIF were retrospectively reviewed. Outcome measures collected for patients with BPS were compared with those with UPFS. Results No associations were found between construct and length of stay (p = 0.5), operative time (p = 0.2), or Odom's criteria (p = 0.7); 79% of patients in the UPFS group as compared with 71.5% in the BPS group had good or excellent outcomes. Mean follow-up was 17.7 months for the UPFS group and 20.2 months for the BPS group. There was one complication in each group, including a seroma in the BPS group and a revision operation in the UPFS group. Implant costs for the BPS group were 35% greater than the UPFS group. Conclusions The present study is the first to demonstrate that patients undergoing MIS TLIF with BPS as compared with UPFS for single-level degenerative lumbar disease had similar clinical outcomes.