Decompression of the spinal cord improves recovery after acute experimental spinal cord compression injury

A Clinical Practice Guideline on the Timing of Surgical Decompression and Hemodynamic Management of Acute Spinal Cord Injury and the Prevention, Diagnosis, and Management of Intraoperative Spinal Cord Injury: Introduction, Rationale, and Scope

STUDY DESIGN

Protocol for the development of clinical practice guidelines following the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) standards.

OBJECTIVES

Acute SCI or intraoperative SCI (ISCI) can have devastating physical and psychological consequences for patients and their families. The treatment of SCI has dramatically evolved over the last century as a result of preclinical and clinical research that has addressed important knowledge gaps, including injury mechanisms, disease pathophysiology, medical management, and the role of surgery. In an acute setting, clinicians are faced with critical decisions on how to optimize neurological recovery in patients with SCI that include the role and timing of surgical decompression and the best strategies for hemodynamic management. The lack of consensus surrounding these treatments has prevented standardization of care across centers and has created uncertainty with respect to how to best manage patients with SCI. ISCI is a feared complication that can occur in the best of hands. Unfortunately, there are no systematic reviews or clinical practice guidelines to assist spine surgeons in the assessment and management of ISCI in adult patients undergoing spinal surgery. Given these limitations, it is the objective of this initiative to develop evidence-based recommendations that will inform the management of both SCI and ISCI. This protocol describes the rationale for developing clinical practice guidelines on (i) the timing of surgical decompression in acute SCI; (ii) the hemodynamic management of acute SCI; and (iii) the prevention, identification, and management of ISCI in patients undergoing surgery for spine-related pathology.

METHODS

Systematic reviews were conducted according to PRISMA standards in order to summarize the current body of evidence and inform the guideline development process. The guideline development process followed the approach proposed by the GRADE working group. Separate multidisciplinary, international groups were created to perform the systematic reviews and formulate the guidelines. All potential conflicts of interest were vetted in advance. The sponsors exerted no influence over the editorial process or the development of the guidelines.

RESULTS

This process resulted in both systematic reviews and clinical practice guidelines/care pathways related to the role and timing of surgery in acute SCI; the optimal hemodynamic management of acute SCI; and the prevention, diagnosis and management of ISCI.

CONCLUSIONS

The ultimate goal of this clinical practice guideline initiative was to develop evidence-based recommendations for important areas of controversy in SCI and ISCI in hopes of improving neurological outcomes, reducing morbidity, and standardizing care across settings. Throughout this process, critical knowledge gaps and future directions were also defined.

An Update of a Clinical Practice Guideline for the Management of Patients With Acute Spinal Cord Injury: Recommendations on the Role and Timing of Decompressive Surgery

STUDY DESIGN

Clinical practice guideline development.

OBJECTIVES

Acute spinal cord injury (SCI) can result in devastating motor, sensory, and autonomic impairment; loss of independence; and reduced quality of life. Preclinical evidence suggests that early decompression of the spinal cord may help to limit secondary injury, reduce damage to the neural tissue, and improve functional outcomes. Emerging evidence indicates that "early" surgical decompression completed within 24 hours of injury also improves neurological recovery in patients with acute SCI. The objective of this clinical practice guideline (CPG) is to update the 2017 recommendations on the timing of surgical decompression and to evaluate the evidence with respect to ultra-early surgery (in particular, but not limited to, <12 hours after acute SCI).

METHODS

A multidisciplinary, international, guideline development group (GDG) was formed that consisted of spine surgeons, neurologists, critical care specialists, emergency medicine doctors, physical medicine and rehabilitation professionals, as well as individuals living with SCI. A systematic review was conducted based on accepted methodological standards to evaluate the impact of early (within 24 hours of acute SCI) or ultra-early (in particular, but not limited to, within 12 hours of acute SCI) surgery on neurological recovery, functional outcomes, administrative outcomes, safety, and cost-effectiveness. The GRADE approach was used to rate the overall strength of evidence across studies for each primary outcome. Using the "evidence-to-recommendation" framework, recommendations were then developed that considered the balance of benefits and harms, financial impact, patient values, acceptability, and feasibility. The guideline was internally appraised using the Appraisal of Guidelines for Research and Evaluation (AGREE) II tool.

RESULTS

The GDG recommended that early surgery (≤24 hours after injury) be offered as the preferred option for adult patients with acute SCI regardless of level. This recommendation was based on moderate evidence suggesting that patients were 2 times more likely to recover by ≥ 2 ASIA Impairment Score (AIS) grades at 6 months (RR: 2.76, 95% CI 1.60 to 4.98) and 12 months (RR: 1.95, 95% CI 1.26 to 3.18) if they were decompressed within 24 hours compared to after 24 hours. Furthermore, patients undergoing early surgery improved by an additional 4.50 (95% 1.70 to 7.29) points on the ASIA Motor Score compared to patients undergoing surgery after 24 hours post-injury. The GDG also agreed that a recommendation for ultra-early surgery could not be made on the basis of the current evidence because of the small sample sizes, variable definitions of what constituted ultra-early in the literature, and the inconsistency of the evidence.

CONCLUSIONS

It is recommended that patients with an acute SCI, regardless of level, undergo surgery within 24 hours after injury when medically feasible. Future research is required to determine the differential effectiveness of early surgery in different subpopulations and the impact of ultra-early surgery on neurological recovery. Moreover, further work is required to define what constitutes effective spinal cord decompression and to individualize care. It is also recognized that a concerted international effort will be required to translate these recommendations into policy.

Progression in translational research on spinal cord injury based on microenvironment imbalance

Spinal cord injury (SCI) leads to loss of motor and sensory function below the injury level and imposes a considerable burden on patients, families, and society. Repair of the injured spinal cord has been recognized as a global medical challenge for many years. Significant progress has been made in research on the pathological mechanism of spinal cord injury. In particular, with the development of gene regulation, cell sequencing, and cell tracing technologies, in-depth explorations of the SCI microenvironment have become more feasible. However, translational studies related to repair of the injured spinal cord have not yielded significant results. This review summarizes the latest research progress on two aspects of SCI pathology: intraneuronal microenvironment imbalance and regenerative microenvironment imbalance. We also review repair strategies for the injured spinal cord based on microenvironment imbalance, including medications, cell transplantation, exosomes, tissue engineering, cell reprogramming, and rehabilitation. The current state of translational research on SCI and future directions are also discussed. The development of a combined, precise, and multitemporal strategy for repairing the injured spinal cord is a potential future direction.

Early versus Delayed Surgery for Acute Traumatic Cervical/Thoracic Spinal Cord Injury in Beijing, China: The Results of a Prospective, Multicenter Nonrandomized Controlled Trial

OBJECTIVES

To compare the effects of early surgery (within 24 h) and delayed surgery on the outcomes of patients with acute cervical/thoracic spinal cord injury (SCI) in Beijing, China.

METHODS

We conducted a clinical trial involving patients who were aged 16-85 years, had acute SCI from 1 June 2016 to 1 June 2019 in Beijing. The enrolled patients were divided into two groups according to the timing of surgical decompression. The primary outcome was the ordinal change in the American Spinal Injury Association Impairment Scale (AIS) grade. The secondary outcomes included the surgical time, volume of surgical bleeding, rate of admission to the intensive care unit (ICU), length of stay in the ICU, duration of mechanical ventilation, length of hospital stay, and postoperative complications. And the time consumption of different phases before operation was recorded for the patients transported to hospital by ambulance.

RESULTS

A total of 148 patients were included in the study, including 55 in the early surgery group and 93 in the delayed surgery group. At 52 weeks post-surgery, 27.3% of the patients in the early surgery group showed AIS improvement by at least two grades, compared to 8.7% of the patients in the delayed surgery group (P = 0.102). According to the logistic regression analysis, the odds of at least a two-grade AIS improvement was six times higher among the patients who underwent early surgery than among those who underwent delayed surgery (OR = 6.66, 95%CI 1.14-38.84). The delay surgery group consumed significantly more time in the phases of transfer and inspection or examination than the early surgery group, and the Chinese regional trauma treatment system was widely used in the early surgery group.

CONCLUSION

Decompression within 24 h after SCI can improve patients' recovery of neurological function without increasing the incidence of postoperative complications and surgical risks. The Chinese regional trauma treatment system can improve the diagnosis and treatment efficiency of patients with acute SCI and speed up the operation timing.

The Central Cord Score: A Novel Classification and Scoring System Specific to Acute Traumatic Central Cord Syndrome

BACKGROUND

Acute traumatic central cord syndrome (ATCCS) is the most common form of spinal cord injury in the United States. Treatment remains controversial, which is a consequence of ATCCS having an inherently different natural history from conventional spinal cord injury, thus requiring a separate classification system. We devised a novel Central Cord Score (CCscore), which both guides treatment and tracks improvement over time with symptoms specific to ATCCS.

METHODS

Medical records of patients with a diagnosis of ATCCS were retrospectively reviewed at a single institution. The CCscore was devised based on signs, symptoms, and imaging findings we believed to be critical in assessing severity of ATCCS. Numeric values were assigned for distal upper extremity motor strength, upper extremity sensation, ambulatory status, magnetic resonance imaging cord signal, and urinary retention.

RESULTS

We identified 51 patients with follow-up data; there were 17 cases of mild injury (CCscore 1-5), 23 moderate cases (CCscore 6-10), and 11 severe cases (CCscore 11-15). Patients treated surgically had significantly greater improvement in upper extremity motor scores and total CCscore only up to 3 months. In terms of timing of surgery, patients treated <24 hours after injury had significantly improved upper extremity motor scores and overall CCscores at last follow-up of ≥3 months.

CONCLUSIONS

Based on these data and their alignment with past literature, the CCscore is able to objectively and specifically categorize the severity and outcome of ATCCS, which represents a step forward in the quest to determine the ultimate efficacy and timing of surgery for ATCCS.

Variability in time to surgery for patients with acute thoracolumbar spinal cord injuries

There are limited data pertaining to current practices in timing of surgical decompression for acute thoracolumbar spinal cord injury (SCI). We conducted a retrospective cohort study to evaluate variability in timing between- and within-trauma centers in North America; and to identify patient- and hospital-level factors associated with treatment delay. Adults with acute thoracolumbar SCI who underwent decompressive surgery within five days of injury at participating trauma centers in the American College of Surgeons Trauma Quality Improvement Program were included. Mixed-effects regression with a random intercept for trauma center was used to model the outcome of time to surgical decompression and assess risk-adjusted variability in surgery timeliness across centers. 3,948 patients admitted to 214 TQIP centers were eligible. 28 centers were outliers, with a significantly shorter or longer time to surgery than average. Case-mix and hospital characteristics explained < 1% of between-hospital variability in surgical timing. Moreover, only 7% of surgical timing variability within-centers was explained by case-mix characteristics. The adjusted intraclass correlation coefficient of 12% suggested poor correlation of surgical timing for patients with similar characteristics treated at the same center. These findings support the need for further research into the optimal timing of surgical intervention for thoracolumbar SCI.

Current updates on various treatment approaches in the early management of acute spinal cord injury

Spinal cord injury (SCI) is a debilitating condition which often leads to a severe disability and ultimately impact patient's physical, psychological, and social well-being. The management of acute SCI has evolved over the couple of decades due to improved understanding of injury mechanisms and increasing knowledge of disease. Currently, the early management of acute SCI patient includes pharmacological agents, surgical intervention and newly experimental neuroprotective strategies. However, many controversial areas are still surrounding in the current treatment strategies for acute SCI, including the optimal timing of surgical intervention, early versus delayed decompression outcome benefits, the use of methylprednisolone. Due to the lack of consensus, the optimal standard of care has been varied across treatment centres. The authors have shed a light on the current updates on early treatment approaches and neuroprotective strategies in the initial management of acute SCI in order to protect the early neurologic injury and reduce the future disability.

A Randomized Controlled Trial of Early versus Late Surgical Decompression for Thoracic and Thoracolumbar Spinal Cord Injury in 73 Patients

Convincing clinical evidence exists to support early surgical decompression in the setting of cervical spinal cord injury (SCI). However, clinical evidence on the effect of early surgery in patients with thoracic and thoracolumbar (from T1 to L1 [T1–L1]) SCI is lacking and a critical knowledge gap remains. This randomized controlled trial (RCT) sought to evaluate the safety and efficacy of early (<24 h) compared with late (24–72 h) decompressive surgery after T1–L1 SCI. From 2010 to 2018, patients (≥16 years of age) with acute T1–L1 SCI presenting to a single trauma center were randomized to receive either early (<24 h) or late (24–72 h) surgical decompression. The primary outcome was an ordinal change in American Spinal Injury Association (ASIA) Impairment Scale (AIS) grade at 12-month follow-up. Secondary outcomes included complications and change in ASIA motor score (AMS) at 12 months. Outcome assessors were blinded to treatment assignment.

Of 73 individuals whose treatment followed the study protocol, 37 received early surgery and 36 underwent late surgery. The mean age was 29.74 ± 11.4 years. In the early group 45.9% of patients and in the late group 33.3% of patients had a ≥1-grade improvement in AIS (odds ratio [OR] 1.70, 95% confidence interval [CI]: 0.66-4.39, p = 0.271); significantly more patients in the early (24.3%) than late (5.6%) surgery group had a ≥2-grade improvement in AIS (OR 5.46, 95% CI: 1.09-27.38, p = 0.025). There was no statistically significant difference in the secondary outcome measures. Surgical decompression within 24 h of acute traumatic T1–L1 SCI is safe and is associated with improved neurological outcome, defined as at least a 2-grade improvement in AIS at 12 months.

Effect of Velocity and Duration of Residual Compression in a Rat Dislocation Spinal Cord Injury Model

Early decompression of the traumatically injured and persistently compressed spinal cord is intuitively beneficial for neurological outcome. Despite considerable pre-clinical evidence of a neurological benefit to early decompression, the effect of early surgical decompression in clinical spinal cord injury (SCI) remains less clear. The discrepancy between pre-clinical and clinical results may be due to differences between the biomechanical variables used in pre-clinical animal models and the biomechanical conditions occurring in clinical injuries. These pre-clinical variables include region of spinal cord, velocity of impact, and injury mechanism. In this study, the effect of velocity and duration of residual compression on injury severity were evaluated using a novel, rodent model of cervical dislocation SCI. Fifty-two male Sprague-Dawley rats were included in five groups: two timings of decompression (24 min, 240 min), two velocities (10 mm/sec, 500 mm/sec), and a sham group. All injuries involved a 1.45-mm dorsal dislocation of the C6 vertebra relative to C5 with subsequent residual compression of 0.8 mm. Animals were evaluated for motor function using the Martinez open field, grip strength, and grooming tests for 6 weeks post-injury. Immunohistochemistry and histology following sacrifice were conducted with counts for NeuN- and choline acetyltransferase (ChAT)-positive neurons, and length of cavitation. Behavioral testing and histological analysis revealed that injuries induced by the high velocity were consistently more severe than those induced by the low velocity, with behavioral correlations ranging between 0.46 and 0.58 (p < 0.05). Longer duration of residual compression did not produce significantly more severe injuries as measured by functional tests and histology. These findings demonstrate that the velocity of the initial traumatic impact may be a more important factor than duration of residual compression in determining SCI severity in a dislocation model of SCI.

Early Surgery for Traumatic Spinal Cord Injury: Where Are We Now?

STUDY DESIGN

Narrative review.

OBJECTIVE

There is a strong biological rationale to perform early decompression after traumatic spinal cord injury (SCI). With an enlarging clinical evidence base, most spine surgeons internationally now favor early decompression for the majority of SCI patients; however, a number of pertinent questions remain surrounding this therapy.

METHODS

A narrative review evaluating the status of early surgery for SCI. In particular, we addressed the following questions: (1) Which patients stand to benefit most from early surgery? 2) What is the most appropriate time threshold defining early surgery?

RESULTS

Although heterogeneity exists, the evidence generally seems to support early surgery. While the best evidence exists for cervical SCI, there is insufficient data to support a differential effect for early surgery depending on neurological level or injury severity. When comparing thresholds to define early versus late surgery-including a later threshold (48-72 hours), an earlier threshold (24 hours), and an ultra-early threshold (8-12 hours)-the 2 earlier time points seem to be associated with the greatest potential for improved outcomes. However, existing prehospital and hospital logistics pose barriers to early surgery in a significant proportion of patients. An overview of recommendations from the recent AOSpine guidelines is provided.

CONCLUSION

In spite of increasing acceptance of early surgery post SCI, further research is needed to (1) identify subgroups of patients who stand to derive particular benefit-in particular to develop more evidence-based approaches for central cord syndrome and (2) investigate the efficacy and feasibility of ultra-early surgery targeting more aggressive timelines.

Early surgical intervention among patients with acute central cord syndrome is not associated with higher mortality and morbidity

Background

Conflicting reports exist regarding mortality and morbidity of early surgical decompression in the setting of acute central cord syndrome (ACS) in multisystem trauma despite evidence of improved neurological outcomes. Consequently, optimal decompression timing in ACS in multisystem trauma patients remains controversial. This study aims to determine the association between early surgery for acute traumatic central cord and all-cause mortality among multisystem trauma patients in the National Trauma Data Bank (NTDB) using propensity score matching.

Methods

We used the NTDB (years 2011-2014) to perform a retrospective cohort study, which included patients >18 years, with ACS (identified using ICD-9 coding). Collected patient data included demographics, surgery timing (≤24 hours, >24 hours), injury mechanism, Charlson comorbidity index (CCI), injury severity score (ISS), serious adverse events (SAE). Logistic regression and propensity matching were used to investigate the relationship between surgery timing and subsequent inpatient mortality.

Results

We identified 2,379 traumatic ACS patients. This group was 79.3% male with an average age of 56.3±15.2. They had an average ISS of 19.5±9.0 and mortality rate of 3.0% (n=72). A total of 731 (30.7%) patients underwent surgery for ACS within 24 hours. Univariate analysis did not show a significantly higher mortality rate in the early versus late surgery groups (3.8% vs. 2.7%, P=0.127). In unadjusted models, early surgery was not predictive of death or SAE + death in full (P=0.129, P=0.140) or matched samples (P=0.137, P=0.280). In models adjusted for age, ISS, and CCI, early surgery was predictive of death and SAE + death using the full sample (P=0.013, P=0.027), but not when using the propensity matched sample (P=0.107, P=0.255).

Conclusions

Early surgical intervention does not appear to be associated with increased mortality among ACS patients unlike previously suggested. We theorize that survival noted within the NTDB is confounded by factors including existing comorbidities and multisystem trauma, rather than surgical timing. Delaying definitive surgical care may predispose patients to worsened greater neurological morbidity.

Multilevel critical stenosis with minimal functional deficits: a case of cervical spondylotic myelopathy

Introduction

We present a case of a previously asymptomatic and highly functional individual whose critical degenerative stenosis was exacerbated by recent trauma (motor vehicle accident), resulting in cervical spondylotic myelopathy.

Case presentation

A 57-year-old African-American man with no significant past medical history presented to the Orthopaedic Surgery outpatient clinic with mild neck discomfort, stiffness, and bilateral hand numbness 4 days after being involved in a motor vehicle accident. He ambulated without assistive devices and displayed a tandem gait pattern with normal cadence. He was minimally tender to palpation at the posterior cervical midline and paraspinal musculature with motor and sensory function intact bilaterally. Reflexes were hypoactive at C5, C6, C7, L4, and S1 bilaterally with positive Babinski signs bilaterally. Imaging revealed degenerative changes, spinal stenosis, and cord compression. The patient eventually underwent posterior cervical decompression and fusion from the C3 to the C6 level, with the only reported complication being transient loss of somatosensory evoked potential (SSEP) signals intra-operatively. In the postoperative period, the patient complained of stiffness in his left shoulder, elbow, and hand, as well as left hand palmar numbness and an inability to make a full fist. His complaints were managed with medication and physical therapy.

Discussion

This case report highlights the point that stenosis that occurs slowly over time is often well compensated, and patients are commonly asymptomatic at first glance. Often times, acute events tip patients from being asymptomatic to symptomatic, generally warranting invasive intervention to prevent further insults from causing permanent damage.

Early surgical decompression within 8 hours for traumatic spinal cord injury: Is it beneficial? A meta-analysis

Introduction

The aim of this study is to evaluate whether early (<8 h) surgical decompression is better in improving neurologic outcomes than late (≥8 h) surgical decompression for traumatic spinal cord injury (tSCI).

Methods

The various electronic databases were used to detect relevant articles published up until May 2016 that compared the outcomes of early versus late surgery for tSCI. Data searching, extraction, analysis, and quality assessment were performed according to Cochrane Collaboration guidelines. The results are presented as relative ratio (RR) for binary outcomes and mean difference (MD) for continuous outcomes with 95% confidence intervals (CIs).

Results

Seven studies were finally included in this meta-analysis. There were significant differences between the 2 groups in neurologic improvement (MD = 0.54, 95% CI = −18.52 to −7.02, P < 0.0001) and length of hospital stay (MD = −12.77, 95% CI = 0.34–0.74, P < 0.00001). However, no significant differences were found between the 2 groups in perioperative complications (OR = 0.95, 95% CI = 0.35–2.61, P = 0.92).

Conclusions

Early surgical decompression within 8 h after tSCI was beneficial in terms of neurologic improvement compared with late surgery. Early surgical decompression (within 8 h) is recommended for patients with tSCI.

Level of evidence

Level III, therapeutic study.

Intramedullary Lesion Length on Postoperative Magnetic Resonance Imaging is a Strong Predictor of ASIA Impairment Scale Grade Conversion Following Decompressive Surgery in Cervical Spinal Cord Injury

BACKGROUND

Evidence indicates that, over time, patients with spinal cord injury (SCI) improve neurologically in various degrees. We sought to further investigate indicators of grade conversion in cervical SCI.

OBJECTIVE

To detect predictors of ASIA impairment scale (AIS) grade conversion in SCI following surgical decompression.

METHODS

In a retrospective study, demographics, clinical, imaging, and surgical data from 100 consecutive patients were assessed for predictors of AIS grade conversion.

RESULTS

American Spinal Injury Association motor score was 17.1. AIS grade was A in 52%, B in 29%, and C in 19% of patients. Surgical decompression took place on an average of 17.6 h following trauma (≤12 h in 51 and >12 h in 49). Complete decompression was verified by magnetic resonance imaging (MRI) in 73 patients. Intramedullary lesion length (IMLL) on postoperative MRI measured 72.8 mm, and hemorrhage at the injury epicenter was noted in 71 patients. Grade conversion took place in 26.9% of AIS grade A patients, 65.5% of AIS grade B, and 78.9% of AIS grade C. AIS grade conversion had statistical relationship with injury severity score, admission AIS grade, extent of decompression, presence of intramedullary hemorrhage, American Spinal Injury Association motor score, and IMLL. A stepwise multiple logistic regression analysis indicated IMLL was the sole and strongest indicator of AIS grade conversion (odds ratio 0.950, 95% CI 0.931-0.969). For 1- and 10-mm increases in IMLL, the model indicates 4% and 40% decreases, respectively, in the odds of AIS grade conversion.

CONCLUSION

Compared with other surrogates, IMLL remained as the only predictor of AIS grade conversion.

A Clinical Practice Guideline for the Management of Patients With Acute Spinal Cord Injury and Central Cord Syndrome: Recommendations on the Timing (≤24 Hours Versus >24 Hours) of Decompressive Surgery

OBJECTIVE

To develop recommendations on the timing of surgical decompression in patients with traumatic spinal cord injury (SCI) and central cord syndrome.

METHODS

A systematic review of the literature was conducted to address key relevant questions. A multidisciplinary guideline development group used this information, along with their clinical expertise, to develop recommendations for the timing of surgical decompression in patients with SCI and central cord syndrome. Based on GRADE, a strong recommendation is worded as "we recommend," whereas a weak recommendation is presented as "we suggest."

RESULTS

Conclusions from the systematic review included (1) isolated studies reported statistically significant and clinically important improvements following early decompression at 6 months and following discharge from inpatient rehabilitation; (2) in one study on acute central cord syndrome without instability, a marginally significant improvement in total motor scores was reported at 6 and 12 months in patients managed with early versus late surgery; and (3) there were no significant differences in length of acute care/rehabilitation stay or in rates of complications between treatment groups. Our recommendations were: "We suggest that early surgery be considered as a treatment option in adult patients with traumatic central cord syndrome" and "We suggest that early surgery be offered as an option for adult acute SCI patients regardless of level." Quality of evidence for both recommendations was considered low.

CONCLUSIONS

These guidelines should be implemented into clinical practice to improve outcomes in patients with acute SCI and central cord syndrome by promoting standardization of care, decreasing the heterogeneity of management strategies, and encouraging clinicians to make evidence-informed decisions.

Timing of Decompression in Patients With Acute Spinal Cord Injury: A Systematic Review

STUDY DESIGN

Systematic review.

OBJECTIVE

To conduct a systematic review and synthesis of the literature to assess the comparative effectiveness, safety, and cost-effectiveness of early (≤24 hours) versus late decompression (>24 hours) in adults with acute spinal cord injury (SCI).

METHODS

A systematic search was conducted of Medline, EMBASE, the Cochrane Collaboration Library, and Google Scholar to identify studies published through November 6, 2014. Studies published in any language, in humans, and with an abstract were considered for inclusion. Included studies were critically appraised and the overall strength of evidence was determined using methods proposed by the Grading of Recommendation Assessment, Development and Evaluation working group.

RESULTS

The search yielded 449 potentially relevant citations. Sixteen additional primary studies were identified through other sources. Six studies met inclusion criteria. All but 2 studies were considered to have moderately high risk of bias. Across studies and injury levels, the impact of early surgical decompression (≤24 hours) on clinically important improvement in neurological status was variable. Isolated studies reported statistically significant and clinically important improvements at 6 months (cervical injury, low strength of evidence) and following discharge from inpatient rehabilitation (all levels, very low strength of evidence) but not at other time points; another study observed a statistically significant 6 point improvement in ASIA Impairment Scale (AIS) among patients with AIS B, C, or D, but not for those with AIS A (very low strength of evidence). In one study of acute central cord syndrome without instability, a clinically and statistically meaningful improvement in total motor scores was reported at 6 and 12 months in patients treated early (versus late). There were, however, no significant differences in AIS improvement between early and late surgical groups at 6- or 12-months (very low strength of evidence). One of 3 studies found a shorter length of hospital stay associated with early surgical decompression. Of 3 studies reporting on safety, no significant differences in rates of complications (including mortality, neurologic deterioration, pneumonia or pressure ulcers) were noted between early and late decompression groups.

CONCLUSIONS

Results surrounding the efficacy of early versus late decompressive surgery, as well as the quality of evidence available, were variable depending on the level of SCI, timing of follow-up, and specific outcome considered. Existing evidence supports improved neurological recovery among cervical SCI patients undergoing early surgery; however, evidence regarding remaining SCI populations and clinical outcomes was inconsistent.

A Clinical Practice Guideline for the Management of Acute Spinal Cord Injury: Introduction, Rationale, and Scope

Acute spinal cord injury (SCI) is a traumatic event that results in disturbances to normal sensory, motor, or autonomic function and ultimately affects a patient's physical, psychological, and social well-being. The management of patients with SCI has drastically evolved over the past century as a result of increasing knowledge on injury mechanisms, disease pathophysiology, and the role of surgery. There still, however, remain controversial areas surrounding available management strategies for the treatment of SCI, including the use of corticosteroids such as methylprednisolone sodium succinate, the optimal timing of surgical intervention, the type and timing of anticoagulation prophylaxis, the role of magnetic resonance imaging, and the type and timing of rehabilitation. This lack of consensus has prevented the standardization of care across treatment centers and among the various disciplines that encounter patients with SCI. The objective of this guideline is to form evidence-based recommendations for these areas of controversy and outline how to best manage patients with SCI. The ultimate goal of these guidelines is to improve outcomes and reduce morbidity in patients with SCI by promoting standardization of care and encouraging clinicians to make evidence-informed decisions.

Active physiological conservative management in traumatic spinal cord injuries – an evidence-based approach

The management of the traumatic spinal cord injury remains controversial. Guttmann demonstrated that with simultaneous attention to all medical and non-medical effects of the spinal cord injury, a significant number of patients recovered motor and sensory functions to ambulate and the majority were pain-free following conservative management. Active physiological conservative management of the spinal injury requires simultaneous scrupulous care of the injured spine together with; the multisystem neurogenic effects of the spinal cord injury on the respiratory, cardiovascular, urinary, gastrointestinal, dermatological, sexual and reproductive functions; the management of the associated psychological effects of paralysis from the early hours or days of injury as well as; the physical rehabilitation and modification of the environment. To date, there is no evidence to suggest that the surgical decompression and/or stabilisation of the neurologically impaired spinal cord injury patient is advantageous. This article considers the debates and evidence of surgical management including the effects of timing of the surgical decompression. Also addressed are the factors influencing decisions on management, prognostic indicators of recovery and natural history of complete and incomplete cord injuries. Traumatic biomechanical instability of the spine, physiological instability of the spinal cord, traumatic spinal canal encroachment and traumatic cord compression are also discussed. Early mobilisation, indications for surgery at the RJAH and economic considerations of spinal cord injuries are presented. The ultimate goals of the active physiological conservative management are to ensure maximum neurological recovery and independence, a pain-free and flexible spine, safe and convenient functioning of the various systems of the body with minimal inconvenience to patients and the prevention of complications.

Traumatic spinal cord injury: the relationship between pathology and clinical implications

The pathological effects of traumatic spinal cord injuries (SCI) encompass the pathology affecting the spinal cord. As a result of the interruption of spinal cord conduction, one or more pathological and patho-physiological processes affect almost every system of the human body. Knowledge of the pathological processes that affect the spinal cord and the various systems of the body is essential for the safe and good management of these patients. The small incidence (10-15 per million per year) of these highly complex conditions makes it difficult for skills and experience to develop in District General Hospitals in the management of these patients. The associated sensory impairment or loss present diagnostic challenges to the clinician in almost every aspect of paralysis and throughout the patient’s life.

In the acute stage simultaneous good management of the multi-system impairments and malfunctions giving equal attention to all systems including that of the traumatized spine is the key to good quality outcome. Concentrating resources at any one time on any one particular aspect of paralysis is unlikely to yield a similarly good outcome. The neurological outcome does not depend only on the quality of the management of the SCI. The traumatized physiologically unstable spinal cord is vulnerable and unable to protect itself from non-mechanical complications outside the spinal canal, many of which can easily develop in patients with SCI adding to the threats from the biomechanical instability.

To date there are many controversies in the management of many aspects of paralysis at all stages following injury. One of the main current controversies is in the management of the SCI itself. There are many reasons that seem to perpetuate this controversy. Some of the reasons may be related to different interpretations of the pathological processes that affect the vertebral axis and the spinal cord as well as their effects on neurological outcome. The natural history of neurological recovery following SCI is not always duly acknowledged.

Optimal Timing of Surgical Decompression for Acute Traumatic Central Cord Syndrome: A Systematic Review of the Literature

BACKGROUND

Traumatic central cord syndrome (TCCS) is an incomplete spinal cord injury defined by greater weakness in upper versus lower extremities, variable sensory loss, and variable bladder, bowel, and sexual dysfunction. The optimal timing of surgery for TCCS remains controversial.

OBJECTIVE

To determine whether timing of surgery for TCCS predicts neurological outcomes, length of stay, and complications.

METHODS

Five databases were searched through March 2015. Articles were appraised independently by 2 reviewers, and the evidence synthesized according to Grading of Recommendation Assessment, Development and Evaluation principles.

RESULTS

Nine studies (3 prognostic, 5 therapeutic, 1 both) satisfied inclusion criteria. Low level evidence suggests that patients operated on <24 hours after injury exhibit significantly greater improvements in postoperative American Spinal Injury Association motor scores and the functional independence measure at 1 year than those operated on >24 hours after injury. Moderate evidence suggests that patients operated on <2 weeks after injury have a higher postoperative Japanese Orthopaedic Association score and recovery rate than those operated on >2 weeks after injury. There is insufficient evidence that lengths of hospital or intensive care unit stay differ between patients who undergo early versus delayed surgery. Furthermore, there is insufficient evidence that timing between injury and surgery predicts mortality rates or serious or minor adverse events.

CONCLUSION

Surgery for TCCS <24 hours after injury appears safe and effective. Although there is insufficient evidence to provide a clear recommendation for early surgery (<24 hours), it is preferable to operate during the first hospital admission and <2 weeks after injury.

Early versus delayed decompression in acute subaxial cervical spinal cord injury: A prospective outcome study at a Level I trauma center from India

Aims:

This study was done with the aim to compare the clinical outcome and patients’ quality of life between early versus delayed surgically treated patients of acute subaxial cervical spinal cord injury. The current study was based on the hypothesis that early surgical decompression and fixations in acute subaxial cervical spinal cord trauma is safe and is associated with improved outcome as compared to delayed surgical decompression.

Materials and Methods:

A total of 69 patients were recruited and divided into early decompression surgery Group A (operated within 48 h of trauma; n = 23) and late/delayed decompression surgery Group B (operated between 48 h and 7 days of trauma; n = 46). The patients in both groups were followed up, and comparative differences noted in the neurological outcome, quality of life, and bony fusion.

Results:

The early surgery group spent lesser days in the intensive care unit and hospital (Group A 28.6 vs. Group B 35 days) had lesser postoperative complications (Group A 43% vs. Group B 61%) and a reduced mortality (Group A 30% vs. Group B 45%). In Group A, 38% patients had 1 American Spinal Injury Association (ASIA) grade improvement while 31% experienced >2 ASIA grade improvement. In Group B, the neurological improvement was 27% and 32%, respectively (P = 0.7). There was a significant improvement in the postoperative quality of life scores in both groups.

Conclusion:

Early surgery in patients with acute subaxial cervical spine injury should be considered strongly in view of the lesser complications, early discharge, and reduced mortality.

Optogenetics applications for treating spinal cord injury

Cases of spinal cord injury (SCI) are increasing all over the world; and in USA alone, there are 273,000 patients, which not only leads to morbidity and mortality but also results in a great economic burden. Many approaches are being used at the pre-clinical and clinical level to treat SCI including therapeutic agents, surgical decompression, stem cell therapy etc. Recently, a new approach called optogenetics has emerged in which light sensitive proteins are used to switch neurons on and off, and this approach has great potential to be used as therapy due to its specificity and rapid response in milliseconds. Few animal studies have been performed so far in which the respiratory and bladder function of rats was restored through the use of optogenetics. On the basis of promising results obtained, in the future, this approach can prove to be a valuable tool to treat patients with SCI.

Current and future medical therapeutic strategies for the functional repair of spinal cord injury

Spinal cord injury (SCI) leads to social and psychological problems in patients and requires costly treatment and care. In recent years, various pharmacological agents have been tested for acute SCI. Large scale, prospective, randomized, controlled clinical trials have failed to demonstrate marked neurological benefit in contrast to their success in the laboratory. Today, the most important problem is ineffectiveness of nonsurgical treatment choices in human SCI that showed neuroprotective effects in animal studies. Recently, attempted cellular therapy and transplantations are promising. A better understanding of the pathophysiology of SCI started in the early 1980s. Research had been looking at neuroprotection in the 1980s and the first half of 1990s and regeneration studies started in the second half of the 1990s. A number of studies on surgical timing suggest that early surgical intervention is safe and feasible, can improve clinical and neurological outcomes and reduce health care costs, and minimize the secondary damage caused by compression of the spinal cord after trauma. This article reviews current evidence for early surgical decompression and nonsurgical treatment options, including pharmacological and cellular therapy, as the treatment choices for SCI.

Motor and histological findings in a model of sci: comparison between posterior and lateral clips

Objective: To evaluate the locomotor and histological impact on the spinal cord comparing lateral and posterior clip placement. Method: Randomized experimental trial. Twenty female Wistar rats, weighing between 250 and 300 grams and aged 12-14 weeks were randomized in two groups according to the placement of the clip: lateral group (N=10) and posterior group (N=10). After exposing the thoracic segment of the spine (T8-T10), a laminectomy was performed at the T9 level under microscopic view. The spinal cord injury was made using a 5 mm long aneurysm clip with a closing pressure of 50 grams. Locomotor behavior was evaluated by the Basso, Beattie and Bresnahan scale in days 1, 7, 14, 21, and 28 after surgery. The area of injury was assessed by histological analysis and measured by a software. Results: The histological evaluation showed a larger mean area of 4.8&#177;1mm&#178; of lesion (P=0.03) in the lateral group when compared with the posterior group mean area of 2.3&#177;2mm&#178;. There was no significant difference between lateral and posterior groups with respect to locomotor scores from day 1 to 28 (P=0.361). Conclusion: The lesion area observed in the spinal cord histology after lateral placement of a clip was significantly bigger than in the posterior placement. The motor evaluation showed similar BBB scores regardless of the type of clamping method.

The influence of time from injury to surgery on motor recovery and length of hospital stay in acute traumatic spinal cord injury: an observational Canadian cohort study

To determine the influence of time from injury to surgery on neurological recovery and length of stay (LOS) in an observational cohort of individuals with traumatic spinal cord injury (tSCI), we analyzed the baseline and follow-up motor scores of participants in the Rick Hansen Spinal Cord Injury Registry to specifically assess the effect of an early (less than 24 h from injury) surgical procedure on motor recovery and on LOS. One thousand four hundred and ten patients who sustained acute tSCIs with baseline American Spinal Injury Association Impairment Scale (AIS) grades A, B, C, or D and were treated surgically were analyzed to determine the effect of the timing of surgery (24, 48, or 72 h from injury) on motor recovery and LOS. Depending on the distribution of data, we used different types of generalized linear models, including multiple linear regression, gamma regression, and negative binomial regression. Persons with incomplete AIS B, C, and D injuries from C2 to L2 demonstrated motor recovery improvement of an additional 6.3 motor points (SE=2.8 p<0.03) when they underwent surgical treatment within 24 h from the time of injury, compared with those who had surgery later than 24 h post-injury. This beneficial effect of early surgery on motor recovery was not seen in the patients with AIS A complete SCI. AIS A and B patients who received early surgery experienced shorter hospital LOS. While the issues of when to perform surgery and what specific operation to perform remain controversial, this work provides evidence that for an incomplete acute tSCI in the cervical, thoracic, or thoracolumbar spine, surgery performed within 24 h from injury improves motor neurological recovery. Early surgery also reduces LOS.

Increased spinal cord movements in cervical spondylotic myelopathy

BACKGROUND CONTEXT

Magnetic resonance imaging (MRI) is a very useful diagnostic test for cervical spondylotic myelopathy (CSM) because it can identify degenerative changes within the spinal cord (SC), disclose the extent, localization, and the kind of SC compression, and help rule out other SC disorders. However, the relationships between changes in cerebrospinal fluid (CSF) flow, cord motion, the extent and severity of spinal canal stenosis, and the development of CSM symptoms are not well understood.

PURPOSE

To evaluate if changes in the velocity of CSF and SC movements provide additional insight into the pathophysiological mechanisms underlying CSM beyond MRI observations of cord compression.

STUDY DESIGN

Prospective radiologic study of recruited patients.

PATIENT SAMPLE

Thirteen CSM subjects and 15 age and gender matched controls.

OUTCOME MEASURES

Magnetic resonance imaging measures included CSF and SC movement. Cervical cord condition was assessed by the Japanese Orthopaedic Association (JOA) score, compression ratio (CR), and somatosensory evoked potentials (SSEPs) of the tibial and ulnar nerves.

METHODS

Phase-contrast imaging at the level of stenosis for patients and at C5 for controls and T2-weighted images were compared with clinical findings.

RESULTS

Cerebrospinal fluid velocity was significantly reduced in CSM subjects as compared with controls and was related to cord CR. Changes in CSF velocity and cord compression were not correlated with clinical measures (JOA scores, SSEP) or the presence of T2 hyperintensities. Spinal cord movements, that is, cord displacement and velocity in the craniocaudal axis, were increased in CSM patients. Increased SC movements (ie, total cord displacement) both in the controls and CSM subjects were associated with altered spinal conduction as assessed by SSEP.

CONCLUSIONS

This study revealed rather unexpected increased cord movements in the craniocaudal axis in CSM patients that may contribute to myelopathic deteriorations in combination with spinal canal compression. Understanding the relevance of cord movements with respect to supporting the clinical CSM diagnosis or disease monitoring requires further long-term follow-up studies.

From basics to clinical: a comprehensive review on spinal cord injury

Spinal cord injury (SCI) is a devastating neurological disorder that affects thousands of individuals each year. Over the past decades an enormous progress has been made in our understanding of the molecular and cellular events generated by SCI, providing insights into crucial mechanisms that contribute to tissue damage and regenerative failure of injured neurons. Current treatment options for SCI include the use of high dose methylprednisolone, surgical interventions to stabilize and decompress the spinal cord, and rehabilitative care. Nonetheless, SCI is still a harmful condition for which there is yet no cure. Cellular, molecular, rehabilitative training and combinatorial therapies have shown promising results in animal models. Nevertheless, work remains to be done to ascertain whether any of these therapies can safely improve patient's condition after human SCI. This review provides an extensive overview of SCI research, as well as its clinical component. It starts covering areas from physiology and anatomy of the spinal cord, neuropathology of the SCI, current clinical options, neuronal plasticity after SCI, animal models and techniques to assess recovery, focusing the subsequent discussion on a variety of promising neuroprotective, cell-based and combinatorial therapeutic approaches that have recently moved, or are close, to clinical testing.

Meta-analysis of pre-clinical studies of early decompression in acute spinal cord injury: a battle of time and pressure

Background

The use of early decompression in the management of acute spinal cord injury (SCI) remains contentious despite many pre-clinical studies demonstrating benefits and a small number of supportive clinical studies. Although the pre-clinical literature favours the concept of early decompression, translation is hindered by uncertainties regarding overall treatment efficacy and timing of decompression.

Methods

We performed meta-analysis to examine the pre-clinical literature on acute decompression of the injured spinal cord. Three databases were utilised; PubMed, ISI Web of Science and Embase. Our inclusion criteria consisted of (i) the reporting of efficacy of decompression at various time intervals (ii) number of animals and (iii) the mean outcome and variance in each group. Random effects meta-analysis was used and the impact of study design characteristics assessed with meta-regression.

Results

Overall, decompression improved behavioural outcome by 35.1% (95%CI 27.4-42.8; I²=94%, p<0.001). Measures to minimise bias were not routinely reported with blinding associated with a smaller but still significant benefit. Publication bias likely also contributed to an overestimation of efficacy. Meta-regression demonstrated a number of factors affecting outcome, notably compressive pressure and duration (adjusted r²=0.204, p<0.002), with increased pressure and longer durations of compression associated with smaller treatment effects. Plotting the compressive pressure against the duration of compression resulting in paraplegia in individual studies revealed a power law relationship; high compressive forces quickly resulted in paraplegia, while low compressive forces accompanying canal narrowing resulted in paresis over many hours.

Conclusion

These data suggest early decompression improves neurobehavioural deficits in animal models of SCI. Although much of the literature had limited internal validity, benefit was maintained across high quality studies. The close relationship of compressive pressure to the rate of development of severe neurological injury suggests that pressure local to the site of injury might be a useful parameter determining the urgency of decompression.

The pressure distribution of cerebrospinal fluid responds to residual compression and decompression in an animal model of acute spinal cord injury

STUDY DESIGN

In vivo large animal (pig) model study of cerebrospinal fluid (CSF) pressures after acute experimental spinal cord injury (SCI).

OBJECTIVE

To determine how the CSF pressure (CSFP) and CSF pulse pressure amplitude (CSFPPA) cranial and caudal to the injury site change after an acute SCI with subsequent thecal occlusion and decompression.

SUMMARY OF BACKGROUND DATA

Lowering intrathecal pressure via CSF drainage is currently instituted to prevent ischemia-induced SCI during thoracoabdominal aortic aneurysm surgery and was recently investigated as a potential intervention for acute traumatic SCI. However, in SCI patients, persistent extradural compression commonly occludes the subarachnoid space. This may generate a CSFP differential across the injury site, which cannot be appreciated with lumbar catheter pressure measurements.

METHODS

Anesthetized pigs were subjected to an acute contusive SCI at T11 and 8 hours of sustained compression (n = 12), or sham surgery (n = 2). CSFP was measured cranial and caudal to the injury site, using miniature pressure transducers, during compression and for 6 hours after decompression.

RESULTS

The cranial-caudal CSFP differential increased (mean, 0.39 mm Hg/h), predominantly due to increased cranial pressure. On decompression, cranial CSFP decreased (mean, -1.16 mm Hg) and caudal CSFP increased (mean, 0.65 mm Hg). The CSFP differential did not change significantly after decompression. Cranial CSFPPA was greater than caudal CSFPPA, but this differential did not change during compression. On decompression, the caudal CSFPPA increased in some but not all animals.

CONCLUSION

Although extradural compression exists at the site of injury, lumbar CSFP may not accurately indicate CSFP cranial to the injury. Decompression may provide immediate, though perhaps partial, resolution of the pressure differential. CSFPPA was not a consistent indicator of decompression in this animal model. These findings may have implications for the design of future clinical protocols in which CSFP is monitored after acute SCI.

Surgical treatment for acute spinal cord injury study pilot study #2: evaluation of protocol for decompressive surgery within 8 hours of injury

Acute spinal cord injury (SCI) is a major public health problem for which there is still only limited treatment available. The National Acute Spinal Cord Injury Study-2 (NASCIS-2) and -3 clinical trials demonstrated that the use of acute pharmacotherapy with methylprednisolone can attenuate the secondary injury cascade if administered within 8 hours of acute SCI. However, no trial has been performed to examine whether acute surgical decompressive procedures within this critical 8-hour time window can improve patients' neurological outcome. The purpose of the current prospective Surgical Treatment for Acute Spinal Cord Injury Study (STASCIS) pilot study was to determine the feasibility of obtaining a radiological diagnosis of spinal canal compromise of 25% or more and to perform spinal cord (C3-T1) decompressive procedures by 8 hours postinjury. One of the following three decompressive methods was used: 1) traction alone; 2) traction and surgery; or 3) surgery alone. Twenty-six patients from eight North American centers were entered into the study between 1996 and 1997. Significant difficulties were encountered in many centers in performing immediate magnetic resonance imaging examination in patients with acute SCI. Fewer than 10% of acute cervical SCI patients could be enrolled into this protocol mainly because the combination of the required time for rescue, resuscitation, transport, imaging study, and surgical preparation exceeded the 8-hour injury-to-decompressive surgery window. Eleven patients underwent decompressive procedures initially by being placed in traction at a mean time of 10.9 hours postinjury. Those patients not undergoing this procedure underwent decompressive surgery at a mean time of 40.1 hours. However, the surgical decompressive procedure was completed within 12 hours in seven patients. As a result of these findings, several major changes have been made to the STASCIS protocol for early decompressive therapy.

Cervical spine alignment during on-field management of potential catastrophic spine injuries

Context:

When cervical spine injuries are suspected, the cervical spine should be immobilized in a neutral position and neck motion controlled in preparation for transport to an emergency facility. Protocols for emergency transport utilizing common devices (cervical collars) and methods (transfer techniques) during these procedures are not entirely evidence based.

Evidence Acquisition:

The medical literature search covered the time period of January 1966 to June 2008 using the following keywords, either alone or in combination: extrication collars, cervical collars, spine orthoses, spinal immobilization, spine board, spinal board, transfer techniques, and back board. Biomedical databases searched included Medline, Web of Science, and Cumulative Index to Nursing and Allied Health Literature (CINAHL [1982 to 2008]). The reference lists of all trials identified were also searched for additional trials.

Methods:

Only trials that directly compared the efficacy or safety of transfer methods and/or immobilization devices were included. Studies that measured voluntary head movement after the fitting of the cervical orthoses and those that did not evaluate motion across individual spinal segments were not included.

Results:

A lift-and-slide transfer method with a full body immobilization device creates less motion than a log-roll maneuver. Extrication-type cervical immobilization collars are limited in their ability to control neck motion in the injured cadaveric model.

Conclusion:

Allied health professionals responsible for the management of the cervical spine–injured patient should become familiar with and employ a lift-and-slide transfer technique in appropriate situations and should not rely exclusively on extrication-type collars to immobilize the neck.

Intramedullary lesion expansion on magnetic resonance imaging in patients with motor complete cervical spinal cord injury

OBJECT

The authors performed a study to determine if lesion expansion occurs in humans during the early hours after spinal cord injury (SCI), as has been established in rodent models of SCI, and to identify factors that might predict lesion expansion.

METHODS

The authors studied 42 patients with acute cervical SCI and admission American Spinal Injury Association Impairment Scale Grades A (35 patients) and B (7 patients) in whom 2 consecutive MRI scans were obtained 3-134 hours after trauma. They recorded demographic data, clinical information, Injury Severity Score (ISS), admission MRI-documented spinal canal and cord characteristics, and management strategies.

RESULTS

The characteristics of the cohort were as follows: male/female ratio 37:5; mean age, 34.6 years; and cause of injury, motor vehicle collision, falls, and sport injuries in 40 of 42 cases. The first MRI study was performed 6.8 ±2.7 hours (mean ± SD) after injury, and the second was performed 54.5 ± 32.3 hours after injury. The rostrocaudal intramedullary length of the lesion on the first MRI scan was 59.2 ± 16.1 mm, whereas its length on the second was 88.5 ± 31.9 mm. The principal factors associated with lesion length on the first MRI study were the time between injury and imaging (p = 0.05) and the time to decompression (p = 0.03). The lesion's rate of rostrocaudal intramedullary expansion in the interval between the first and second MRI was 0.9 ± 0.8 mm/hour. The principal factors associated with the rate of expansion were the maximum spinal cord compression (p = 0.03) and the mechanism of injury (p = 0.05).

CONCLUSIONS

Spinal cord injury in humans is characterized by lesion expansion during the hours following trauma. Lesion expansion has a positive relationship with spinal cord compression and may be mitigated by early surgical decompression. Lesion expansion may be a novel surrogate measure by which to assess therapeutic effects in surgical or drug trials.

Gross morphological changes of the spinal cord immediately after surgical decompression in a large animal model of traumatic spinal cord injury

STUDY DESIGN

Quantitative in vivo ultrasound imaging study of spinal cord and dura morphology after acute experimental spinal cord injury (SCI) and decompression in a pig model.

OBJECTIVE

To study the morphological changes of the spinal cord and dura immediately after surgical decompression for acute SCI.

SUMMARY OF BACKGROUND DATA

Surgical decompression for traumatic SCI is currently a topic of debate. After decompression, relief of bony impingement on the thecal sac and spinal cord can be confirmed intraoperatively. However, postoperative imaging often reveals that the cord has swollen to fill the subarachnoid space. Little is known about the extent and timing of this morphological response.

METHODS

Yucatan miniature pigs received sham surgery (N = 1) or a moderate (N = 6, 20 g, 2.3 m/s) or high (N = 6, 20 g, 4.7 m/s) severity weight-drop SCI followed by 8 hours of sustained compression (100 g) and 6 hours of postdecompression monitoring. Sagittal-plane ultrasound images were used to quantify spinal cord, dura, and subarachnoid space dimensions preinjury and once per hour after decompression.

RESULTS

Animals with a moderate SCI exhibited a residual cord deformation of up to 0.64 mm within 10 minutes of decompression, which tended to resolve during 6 hours because of tissue relaxation and swelling. For animals with high-severity SCIs, cord swelling was immediate and resulted in occlusion of the subarachnoid space within 10 minutes to 5 hours, whereas this occurred for only half of the moderate injury group.

CONCLUSION

Decompression of an acute SCI may result in residual cord deformation followed by gradual swelling or immediate swelling leading to subarachnoid occlusion. The response is dependent on initial injury severity. These observations may partly explain the lack of benefit of decompression in some patients and suggest a need to reduce cord swelling to optimize the clinical outcome after acute SCI.

Controversies in the surgical management of spinal cord injuries

Traumatic spinal cord injury (SCI) affects over 200,000 people in the USA and is a major source of morbidity, mortality, and societal cost. Management of SCI includes several components. Acute management includes medical agents and surgical treatment that usually includes either all or a combination of reduction, decompression, and stabilization. Physical therapy and rehabilitation and late onset SCI problems also play a role. A review of the literature in regard to surgical management of SCI patients in the acute setting was undertaken. The controversy surrounding whether reduction is safe, or not, and whether prereduction magnetic resonance (MR) imaging to rule out traumatic disc herniation is essential is discussed. The controversial role of timing of surgical intervention and the choice of surgical approach in acute, incomplete, and acute traumatic SCI patients are reviewed. Surgical treatment is an essential tool in management of SCI patients and the controversy surrounding the timing of surgery remains unresolved. Presurgical reduction is considered safe and essential in the management of SCI with loss of alignment, at least as an initial step in the overall care of a SCI patient. Future prospective collection of outcome data that would suffice as evidence-based is recommended and necessary.

Early versus delayed decompression for traumatic cervical spinal cord injury: results of the Surgical Timing in Acute Spinal Cord Injury Study (STASCIS)

BACKGROUND

There is convincing preclinical evidence that early decompression in the setting of spinal cord injury (SCI) improves neurologic outcomes. However, the effect of early surgical decompression in patients with acute SCI remains uncertain. Our objective was to evaluate the relative effectiveness of early (<24 hours after injury) versus late (≥ 24 hours after injury) decompressive surgery after traumatic cervical SCI.

METHODS

We performed a multicenter, international, prospective cohort study (Surgical Timing In Acute Spinal Cord Injury Study: STASCIS) in adults aged 16-80 with cervical SCI. Enrolment occurred between 2002 and 2009 at 6 North American centers. The primary outcome was ordinal change in ASIA Impairment Scale (AIS) grade at 6 months follow-up. Secondary outcomes included assessments of complications rates and mortality.

FINDINGS

A total of 313 patients with acute cervical SCI were enrolled. Of these, 182 underwent early surgery, at a mean of 14.2(± 5.4) hours, with the remaining 131 having late surgery, at a mean of 48.3(± 29.3) hours. Of the 222 patients with follow-up available at 6 months post injury, 19.8% of patients undergoing early surgery showed a ≥ 2 grade improvement in AIS compared to 8.8% in the late decompression group (OR = 2.57, 95% CI:1.11,5.97). In the multivariate analysis, adjusted for preoperative neurological status and steroid administration, the odds of at least a 2 grade AIS improvement were 2.8 times higher amongst those who underwent early surgery as compared to those who underwent late surgery (OR = 2.83, 95% CI:1.10,7.28). During the 30 day post injury period, there was 1 mortality in both of the surgical groups. Complications occurred in 24.2% of early surgery patients and 30.5% of late surgery patients (p = 0.21).

CONCLUSION

Decompression prior to 24 hours after SCI can be performed safely and is associated with improved neurologic outcome, defined as at least a 2 grade AIS improvement at 6 months follow-up.

Anatomy and biomechanics of the spinal column and cord

The field of biomechanics combines the disciplines of biology and engineering, attempting to quantitatively describe the complicated properties of biological materials. These properties depend not only upon the inherent attributes of its constituents but also upon how the constituents are arranged relative to each other. Its importance in understanding spinal column and spinal cord pathology cannot be overemphasized. This chapter is a primer on the application of biomechanical principles to the normal and pathological spine. The basic concepts of biomechanics will first be reviewed followed by a review of the structural anatomy of the osteoligamentous spinal column and the biomechanics of injury. Relevant spinal cord anatomy will then be addressed as well as current biomechanical theories of spinal cord injury.

Neuroprotective effects of almond skins in experimental spinal cord injury

BACKGROUND & AIMS

Functional deficits following spinal cord injury (SCI) arise from both mechanical injury and from secondary tissue reactions involving inflammation. Natural almond skins (NS) were tested to evaluate anti-inflammatory effects on an animal model of SCI.

METHODS

SCI was induced by the application of vascular clips to the dura via a four-level T5-T8 laminectomy. In the present study, to elucidate whether the protective effects of NS are related to the total phenolic content, we also investigated the effect of a blanched (BS) almond skins (industrially obtained by removing bran from the nut) in SCI. NS and BS (30 mg/kg respectively) were administered per os, 1 h and 6 h, after SCI.

RESULTS

SCI in mice resulted in severe injury characterized by edema, tissue damage, production of inflammatory mediators and apoptosis (measured by Bax, Bcl-2 and Tunel assay). NS treatment, 1 and 6 h after SCI, reduced all parameters of inflammation as neutrophil infiltration, NF-κB activation, PAR formation, iNOS expression and apoptosis. However, treatment with BS did not exert any protective effect.

CONCLUSIONS

Our results suggest that NS treatment, reducing the development of inflammation and tissue injury, may be useful in the treatment of SCI.

Critical care of traumatic spinal cord injury

Approximately 11 000 people suffer traumatic spinal cord injury (TSCI) in the United States, each year. TSCI incidences vary from 13.1 to 52.2 per million people and the mortality rates ranged from 3.1 to 17.5 per million people. This review examines the critical care of TSCI. The discussion will focus on primary and secondary mechanisms of injury, spine stabilization and immobilization, surgery, intensive care management, airway and respiratory management, cardiovascular complication management, venous thromboembolism, nutrition and glucose control, infection management, pressure ulcers and early rehabilitation, pharmacologic cord protection, and evolving treatment options including the use of pluripotent stem cells and hypothermia.

Emerging approaches to the surgical management of acute traumatic spinal cord injury

Traumatic, spinal cord injury (SCI) is a potentially catastrophic event causing major impact at both a personal and societal level. To date, virtually all therapies that have shown promise at the preclinical stage of study have failed to translate into clinically effective treatments. Surgery is performed in the setting of SCI, with the goals of decompressing the spinal cord and restoring spinal stability. Although a consensus regarding the optimal timing of surgical decompression for SCI has not been reached, much of the preclinical and clinical evidence, as well as a recent international survey of spine surgeons, support performing early surgery (<24 hours). Results of the multicenter, Surgical Trial in Acute Spinal Cord Injury Study (STASCIS), expected later this year, should further clarify this important management issue. The overall goal of this review is to provide an update regarding the current status of surgical therapy for traumatic SCI by reviewing relevant pathophysiology, laboratory, and clinical evidence, as well as to introduce radiologic and clinical tools that aid in the surgical decision-making process.

Spinal cord injury: a systematic review of current treatment options

BACKGROUND

Spinal cord injury (SCI) is a devastating event often resulting in permanent neurologic deficit. Research has revealed an understanding of mechanisms that occur after the primary injury and contribute to functional loss. By targeting these secondary mechanisms of injury, clinicians may be able to offer improved recovery after SCI.

QUESTIONS/PURPOSES

In this review, we highlight advances in the field of SCI by framing three questions: (1) What is the preclinical evidence for the neuroprotective agent riluzole that has allowed this agent to move into clinical trials? (2) What is the preclinical evidence for Rho antagonists that have allowed this group of compounds to move into clinical trials? (3) What is the evidence for early surgical decompression after SCI?

METHODS

We conducted a systematic review of MEDLINE and EMBASE-cited articles related to SCI to address these questions.

RESULTS

As a result of an improved understanding of the secondary mechanisms of SCI, specific clinical strategies have been established. We highlight three strategies that have made their way from bench to bedside: the sodium-glutamate antagonist riluzole, the Rho inhibitor Cethrin, and early surgical decompression. Each of these modalities is under clinical investigation. We highlight the fundamental science that led to this development.

CONCLUSIONS

As our understanding of the fundamental mechanisms of SCI improves, we must keep abreast of these discoveries to translate them into therapies that will hopefully benefit patients. We summarize this process of bench to bedside with regard to SCI.

Timing of decompressive surgery of spinal cord after traumatic spinal cord injury: an evidence-based examination of pre-clinical and clinical studies

While the recommendations for spine surgery in specific cases of acute traumatic spinal cord injury (SCI) are well recognized, there is considerable uncertainty regarding the role of the timing of surgical decompression of the spinal cord in the management of patients with SCI. Given this, we sought to critically review the literature regarding the pre-clinical and clinical evidence on the potential impact of timing of surgical decompression of the spinal cord on outcomes after traumatic SCI. The primary literature search was performed using MEDLINE, CINAHL, EMBASE, and Cochrane databases. A secondary search strategy incorporated articles referenced in prior meta-analyses and systematic and nonsystematic review articles. Two reviewers independently assessed every study with regard to eligibility, level of evidence, and study quality. Of 198 abstracts of pre-clinical studies, 19 experimental studies using animal SCI models fulfilled our inclusion and exclusion criteria. Despite some discrepancies in the results of those pre-clinical studies, there is evidence for a biological rationale to support early decompression of the spinal cord. Of 153 abstracts of clinical studies, 22 fulfilled the inclusion and exclusion criteria. While the vast majority of the clinical studies were level-4 evidence, there were two studies of level-2b evidence. The quality assessment scores varied from 7 to 25 with a mean value of 12.41. While 2 of 22 clinical studies assessed feasibility and safety, 20 clinical studies examined efficacy of early surgical intervention to stabilize and align the spine and to decompress the spinal cord; the most common definitions of early operation used 24 and 72 h after SCI as timelines. A number of studies indicated that patients who undergo early surgical decompression can have similar outcomes to patients who received a delayed decompressive operation. However, there is evidence to suggest that early surgical intervention is safe and feasible and that it can improve clinical and neurological outcomes and reduce health care costs. Based on the current clinical evidence using a Delphi process, an expert panel recommended that early surgical intervention should be considered in all patients from 8 to 24 h following acute traumatic SCI.