Guidelines for the conduct of clinical trials for spinal cord injury (SCI) as developed by the ICCP panel: clinical trial outcome measures

Prognostic value of tissue bridges in cervical spinal cord injury: a longitudinal, multicentre, retrospective cohort study

BACKGROUND

The accuracy of prognostication in patients with cervical spinal cord injury (SCI) needs to be improved. We aimed to explore the prognostic value of preserved spinal tissue bridges-injury-spared neural tissue adjacent to the lesion-for prediction of sensorimotor recovery in a large, multicentre cohort of people with SCI.

METHODS

For this longitudinal study, we included patients with acute cervical SCI (vertebrae C1-C7) admitted to one of three trauma or rehabilitation centres: Murnau, Germany (March 18, 2010-March 1, 2021); Zurich, Switzerland (May 12, 2002-March 2, 2019); and Denver, CO, USA (Jan 12, 2010-Feb 16, 2017). Patients were clinically assessed at admission (baseline), at discharge (3 months), and at 12 months post SCI. Midsagittal tissue bridges were quantified from T2-weighted images assessed at 3-4 weeks post SCI. Fractional regression and unbiased recursive partitioning models, adjusted for age, sex, centre, and neurological level of injury, were used to assess associations between tissue bridge width and baseline-adjusted total motor score, pinprick score, and light touch scores at 3 months and 12 months. Patients were stratified into subgroups according to whether they showed better or worse predicted recovery.

FINDINGS

The cohort included 227 patients: 93 patients from Murnau (22 [24%] female); 43 patients from Zurich (four [9%] female); and 91 patients from Denver (14 [15%] female). 136 of these participants (from Murnau and Zurich) were followed up for up to 12 months. At 3 months, per preserved 1 mm of tissue bridge at baseline, patients recovered a mean of 9·3% (SD 0·9) of maximal total motor score (95% CI 7·5-11.2), 8·6% (0·8) of maximal pinprick score (7·0-10·1), and 10·9% (0·8) of maximal light touch score (9·4-12·5). At 12 months post SCI, per preserved 1 mm of tissue bridge at baseline, patients recovered a mean of 10·9% (1·3) of maximal total motor score (8·4-13·4), 5·7% (1·3) of maximal pinprick score (3·3-8·2), and 6·9% (1·4) of maximal light touch score (4·1-9·7). Partitioning models identified a tissue bridge cutoff width of 2·0 mm to be indicative of higher or lower 3-month total motor, pinprick, and light touch scores, and a cutoff of 4·0 mm to be indicative of higher and lower 12-month scores. Compared with models that contained clinical predictors only, models additionally including tissue bridges had significantly improved prediction accuracy across all three centres.

INTERPRETATION

Tissue bridges, measured in the first few weeks after SCI, are associated with short-term and long-term clinical improvement. Thus, tissue bridges could potentially be used to guide rehabilitation decision making and to stratify patients into more homogeneous subgroups of recovery in regenerative and neuroprotective clinical trials.

FUNDING

Wings for Life, International Foundation for Research in Paraplegia, EU project Horizon 2020 (NISCI grant), and ERA-NET NEURON.

Comprehensive and Visualized Analysis of Interventional Clinical Trials of Spinal Cord Injury in the Past Two Decades: A Bibliometric Study

OBJECTIVE

The aim of this study was to provide a bibliometric analysis of reported clinical trials of interventional spinal cord injury (SCI) and present the current status, global trends, and scholars' knowledge in this field.

METHODS

Data were obtained from PubMed and Web of Science (WOS) Core Collection. A literature screening process was conducted to select reports of interventional SCI clinical trials. Qualitative and quantitative analysis was performed based on information from the WOS database. Co-occurrence analysis of keywords, collaboration analysis, and co-citation analysis were performed using VOSviewer.

RESULTS

A total of 849 articles were selected for analysis. Therapeutic strategies in the articles were classified into 10 subgroups. Locomotor training, local complication-related treatments, and neuromodulation are the top 3 subgroups. Spinal Cord was the most productive and most frequently cited journal in SCI clinical trials. The most productive country, institution, and author are the United States, the University of Miami, and Harvey LA, respectively. The collaboration network analysis shows that researchers and institutions from the United States, Canada, the United Kingdom, and Australia were the pivotal driving forces in this field. Spinal cord injury, rehabilitation, individuals, electrical stimulation, and exercise are the top 5 most frequent keywords. The co-citation analysis shows that the most frequently cited references are all international standards and guidelines of SCI clinical trials.

CONCLUSIONS

There is a broad research collaboration network, although it is distributed unevenly worldwide. International standards and guidelines are needed to conduct high-quality clinical trials in the future.

Does Improvement in American Spinal Injury Association Impairment Scale Grade Correlate With Functional Recovery in All Patients With a Traumatic Spinal Cord Injury?

OBJECTIVE

The aim of the study is to determine what improvement on the American Spinal Injury Impairment Scale correlates with functional status after a traumatic spinal cord injury.

DESIGN

We performed an observational cohort study, analyzing prospective data from 168 patients with traumatic spinal cord injury admitted to a single level 1 trauma center. A multivariable analysis was performed to assess the relationship between functional status (from the Spinal Cord Independence Measure) at 1-year follow-up and American Spinal Injury Impairment Scale grade (baseline and 1-yr follow-up), while taking into account covariables describing the sociodemographic status, trauma severity, and level of neurological injury.

RESULTS

Individuals improving to at least American Spinal Injury Impairment Scale grade D had significantly higher Spinal Cord Independence Measure score compared with those not reaching American Spinal Injury Impairment Scale D (89.3 ± 15.2 vs. 52.1 ± 20.4) and were more likely to reach functional independence (68.5% vs. 3.6%), regardless of the baseline American Spinal Injury Impairment Scale grade. Higher final Spinal Cord Independence Measure was more likely with an initial American Spinal Injury Impairment Scale grade D (β = 1.504; 95% confidence interval = 0.46-2.55), and a final American Spinal Injury Impairment Scale grade D (β = 3.716; 95% CI = 2.77-4.66) or E (β = 4.422; 95% CI = 2.91-5.93).

CONCLUSIONS

Our results suggest that reaching American Spinal Injury Impairment Scale grade D or better 1 yr after traumatic spinal cord injury is highly predictive of significant functional recovery, more so than the actual improvement in American Spinal Injury Impairment Scale grade from the injury to the 1-yr follow-up.

Pattern of neurological recovery in persons with an acute cervical spinal cord injury over the first 14 days post injury

Introduction

Following a traumatic spinal cord injury (SCI) it is critical to document the level and severity of injury. Neurological recovery occurs dynamically after injury and a baseline neurological exam offers a snapshot of the patient's impairment at that time. Understanding when this exam occurs in the recovery process is crucial for discussing prognosis and acute clinical trial enrollment. The objectives of this study were to: (1) describe the trajectory of motor recovery in persons with acute cervical SCI in the first 14 days post-injury; and (2) evaluate if the timing of the baseline neurological assessment in the first 14 days impacts the amount of motor recovery observed.

Methods

Data were obtained from the Rick Hansen Spinal Cord Injury Registry (RHSCIR) site in Vancouver and additional neurological data was extracted from medical charts. Participants with a cervical injury (C1-T1) who had a minimum of three exams (including a baseline and discharge exam) were included. Data on the upper-extremity motor score (UEMS), total motor score (TMS) and American Spinal Injury Association (ASIA) Impairment Scale (AIS) were included. A linear mixed-effect model with additional variables (AIS, level of injury, UEMS, time, time2, and TMS) was used to explore the pattern and amount of motor recovery over time.

Results

Trajectories of motor recovery in the first 14 days post-injury showed significant improvements in both TMS and UEMS for participants with AIS B, C, and D injuries, but was not different for high (C1-4) vs. low (C5-T1) cervical injuries or AIS A injuries. The timing of the baseline neurological examination significantly impacted the amount of motor recovery in participants with AIS B, C, and D injuries.

Discussion

Timing of baseline neurological exams was significantly associated with the amount of motor recovery in cervical AIS B, C, and D injuries. Studies examining changes in neurological recovery should consider stratifying by severity and timing of the baseline exam to reduce bias amongst study cohorts. Future studies should validate these estimates for cervical AIS B, C, and D injuries to see if they can serve as an "adjustment factor" to control for differences in the timing of the baseline neurological exam.

Development of neural repair therapy for chronic spinal cord trauma: soluble Nogo receptor decoy from discovery to clinical trial

PURPOSE OF REVIEW

After traumatic spinal cord injury (SCI), neurological deficits persist due to the disconnection of surviving neurons. While repair of connectivity may restore function, no medical therapy exists today.This review traces the development of the neural repair-based therapeutic AXER-204 from animal studies to the recent clinical trial for chronic cervical SCI.

RECENT FINDINGS

Molecular studies reveal a Nogo-66 Receptor 1 (NgR1, RTN4R) pathway inhibiting axon regeneration, sprouting, and plasticity in the adult mammalian central nervous system (CNS). Rodent and nonhuman primate studies demonstrate that the soluble receptor decoy NgR(310)ecto-Fc or AXER-204 promotes neural repair and functional recovery in transection and contusion SCI. Recently, this biological agent completed a first-in-human and randomized clinical trial for chronic cervical SCI. The intervention was safe and well tolerated. Across all participants, upper extremity strength did not improve with treatment. However, posthoc and biomarker analyses suggest that AXER-204 may benefit treatment-naïve patients with incomplete SCI in the chronic stage.

SUMMARY

NgR1 signaling restricts neurological recovery in animal studies of CNS injury. The recent clinical trial of AXER-204 provides encouraging signals supporting future focused trials of this neural repair therapeutic. Further, AXER-204 studies provide a roadmap for the development of additional and synergistic therapies for chronic SCI.

Early and intensive motor training to enhance neurological recovery in people with spinal cord injury: trial protocol

STUDY DESIGN

Protocol for a multi-centre randomised controlled trial (the SCI-MT trial).

OBJECTIVES

To determine whether 10 weeks of intensive motor training enhances neurological recovery in people with recent spinal cord injury (SCI).

SETTING

Fifteen spinal injury units in Australia, Scotland, England, Italy, Netherlands, Norway, and Belgium.

METHODS

A pragmatic randomised controlled trial will be undertaken. Two hundred and twenty people with recent SCI (onset in the preceding 10 weeks, American Spinal Injuries Association Impairment Scale (AIS) A lesion with motor function more than three levels below the motor level on one or both sides, or an AIS C or D lesion) will be randomised to receive either usual care plus intensive motor training (12 h of motor training per week for 10 weeks) or usual care alone. The primary outcome is neurological recovery at 10 weeks, measured with the Total Motor Score from the International Standards for Neurological Classification of SCI. Secondary outcomes include global measures of motor function, ability to walk, quality of life, participants' perceptions about ability to perform self-selected goals, length of hospital stay and participants' impressions of therapeutic benefit at 10 weeks and 6 months. A cost-effectiveness study and process evaluation will be run alongside the trial. The first participant was randomised in June 2021 and the trial is due for completion in 2025.

CONCLUSIONS

The findings of the SCI-MT Trial will guide recommendations about the type and dose of inpatient therapy that optimises neurological recovery in people with SCI.

TRIAL REGISTRATION

ACTRN12621000091808 (1.2.2021).

Soluble Nogo-Receptor-Fc decoy (AXER-204) in patients with chronic cervical spinal cord injury in the USA: a first-in-human and randomised clinical trial

BACKGROUND

Spinal cord injury (SCI) causes neural disconnection and persistent neurological deficits, so axon sprouting and plasticity might promote recovery. Soluble Nogo-Receptor-Fc decoy (AXER-204) blocks inhibitors of axon growth and promotes recovery of motor function after SCI in animals. This first-in-human and randomised trial sought to determine primarily the safety and pharmacokinetics of AXER-204 in individuals with chronic SCI, and secondarily its effect on recovery.

METHODS

We conducted a two-part study in adults (aged 18-65 years) with chronic (>1 year) cervical traumatic SCI at six rehabilitation centres in the USA. In part 1, AXER-204 was delivered open label as single intrathecal doses of 3 mg, 30 mg, 90 mg, or 200 mg, with primary outcomes of safety and pharmacokinetics. Part 2 was a randomised, parallel, double-blind comparison of six intrathecal doses of 200 mg AXER-204 over 104 days versus placebo. Participants were randomly allocated (1:1) by investigators using a central electronic system, stratified in blocks of four by American Spinal Injury Association Impairment Scale grade and receipt of AXER-204 in part 1. All investigators and patients were masked to treatment allocation until at least day 169. The part 2 primary objectives were safety and pharmacokinetics, with a key secondary objective to assess change in International Standards for Neurological Classification of SCI (ISNCSCI) Upper Extremity Motor Score (UEMS) at day 169 for all enrolled participants. This trial is registered with ClinicalTrials.gov, NCT03989440, and is completed.

FINDINGS

We treated 24 participants in part 1 (six per dose; 18 men, six women), and 27 participants in part 2 (13 placebo, 14 AXER-204; 23 men, four women), between June 20, 2019, and June 21, 2022. There were no deaths and no discontinuations from the study due to an adverse event in part 1 and 2. In part 2, treatment-related adverse events were of similar incidence in AXER-204 and placebo groups (ten [71%] vs nine [69%]). Headache was the most common treatment-related adverse event (five [21%] in part 1, 11 [41%] in part 2). In part 1, AXER-204 reached mean maximal CSF concentration 1 day after dosing with 200 mg of 412 000 ng/mL (SD 129 000), exceeding those concentrations that were efficacious in animal studies. In part 2, mean changes from baseline to day 169 in ISNCSCI UEMS were 1·5 (SD 3·3) for AXER-204 and 0·9 (2·3) for placebo (mean difference 0·54, 95% CI -1·48 to 2·55; p=0·59).

INTERPRETATION

This study delivers the first, to our knowledge, clinical trial of a rationally designed pharmacological treatment intended to promote neural repair in chronic SCI. AXER-204 appeared safe and reached target CSF concentrations; exploratory biomarker results were consistent with target engagement and synaptic stabilisation. Post-hoc subgroup analyses suggest that future trials could investigate efficacy in patients with moderately severe SCI without prior AXER-204 exposure.

FUNDING

Wings for Life Foundation, National Institute of Neurological Disorders and Stroke, National Center for Advancing Translational Sciences, National Institute on Drug Abuse, and ReNetX Bio.

Cell therapies for spinal cord injury: a review of the clinical trials and cell-type therapeutic potential

Spinal cord injury (SCI) is an as yet untreatable neuropathology that causes severe dysfunction and disability. Cell-based therapies hold neuroregenerative and neuroprotective potential, but, although being studied in SCI patients for more than two decades, long-term efficacy and safety remain unproven, and which cell types result in higher neurological and functional recovery remains under debate. In a comprehensive scoping review of 142 reports and registries of SCI cell-based clinical trials, we addressed the current therapeutical trends and critically analysed the strengths and limitations of the studies. Schwann cells, olfactory ensheathing cells (OECs), macrophages and various types of stem cells have been tested, as well as combinations of these and other cells. A comparative analysis between the reported outcomes of each cell type was performed, according to gold-standard efficacy outcome measures like the ASIA impairment scale, motor and sensory scores. Most of the trials were in the early phases of clinical development (phase I/II), involved patients with complete chronic injuries of traumatic aetiology and did not display a randomized comparative control arm. Bone marrow stem cells and OECs were the most commonly tested cells, while open surgery and injection were the main methods of delivering cells into the spinal cord or submeningeal spaces. Transplantation of support cells, such as OECs and Schwann cells, resulted in the highest ASIA Impairment Scale (AIS) grade conversion rates (improvements in ∼40% of transplanted patients), which surpassed the spontaneous improvement rate expected for complete chronic SCI patients within 1 year post-injury (5-20%). Some stem cells, such as peripheral blood-isolated and neural stem cells, offer potential for improving patient recovery. Complementary treatments, particularly post-transplantation rehabilitation regimes, may contribute highly to neurological and functional recovery. However, unbiased comparisons between the tested therapies are difficult to draw, given the great heterogeneity of the design and outcome measures used in the SCI cell-based clinical trials and how these are reported. It is therefore crucial to standardize these trials when aiming for higher value clinical evidence-based conclusions.

Independence and upper extremity functioning after spinal cord injury: a cross-sectional study

Upper extremity functioning is important for achieving independence in activities of daily living (ADL). A better understanding of relationships between different aspects of independence in ADL after spinal cord injury (SCI) and upper extremity functioning is required to guide rehabilitation practices. To determine which aspects of independence in ADL are correlated with upper extremity functioning in individuals with cervical or thoracic SCI. A total of 25 adults (mean age 58.4 years, 72% men) with established cervical or thoracic SCI were recruited. Independence in ADL was assessed by Spinal Cord Independence Measure (SCIM-III) and upper extremity functioning by kinematic measures (movement time, smoothness, and wrist angle during drinking task), grip strength, Upper Extremity Motor and Sensory Score, Box and Block Test (BBT), Action Research Arm Test (ARAT), and Upper Extremity Basic Data Set (ISCI-Hand and ISCI-Shoulder). Spearman correlation coefficients were used for data analyses. The SCIM-self-care subscale, particularly the feeding and dressing items, correlated moderately (r ≥ 0.5) with movement time and smoothness, grip strength, ARAT, BBT, and ISCI-Hand. The SCIM-respiration/sphincter subscale and the SCIM-mobility showed very low and low correlations with upper extremity assessments. However, at item level, respiration and bed/wheelchair mobility showed moderate correlations. Independence in self-care as domain and feeding/dressing, respiration and bed/wheelchair mobility as separate items were dependent on upper extremity functioning in individuals with cervical or thoracic SCI. Movement time and smoothness along with BBT, grip strength, ARAT, and ISCI-Hand can be used as indicators of independence in ADL. These findings can provide guidance to clinical practice in selection of upper extremity assessments in the context for ADL in individuals with SCI.

Recovery of walking in nonambulatory children with chronic spinal cord injuries: Case series

The immature central nervous system is recognized as having substantial neuroplastic capacity. In this study, we explored the hypothesis that rehabilitation can exploit that potential and elicit reciprocal walking in nonambulatory children with chronic, severe (i.e., lower extremity motor score < 10/50) spinal cord injuries (SCIs). Seven male subjects (3-12 years of age) who were at least 1-year post-SCI and incapable of discrete leg movements believed to be required for walking, enrolled in activity-based locomotor training (ABLT; clinicaltrials.gov NCT00488280). Six children completed the study. Following a minimum of 49 sessions of ABLT, three of the six children achieved walking with reverse rolling walkers. Stepping development, however, was not accompanied by improvement in discrete leg movements as underscored by the persistence of synergistic movements and little change in lower extremity motor scores. Interestingly, acoustic startle responses exhibited by the three responding children suggested preserved reticulospinal inputs to circuitry below the level of injury capable of mediating leg movements. On the other hand, no indication of corticospinal integrity was obtained with transcranial magnetic stimulation evoked responses in the same individuals. These findings suggest some children who are not predicted to improve motor and locomotor function may have a reserve of adaptive plasticity that can emerge in response to rehabilitative strategies such as ABLT. Further studies are warranted to determine whether a critical need exists to re-examine rehabilitation approaches for pediatric SCI with poor prognosis for any ambulatory recovery.

Modular organization of locomotor networks in people with severe spinal cord injury

Introduction

Previous studies support modular organization of locomotor circuitry contributing to the activation of muscles in a spatially and temporally organized manner during locomotion. Human spinal circuitry may reorganize after spinal cord injury; however, it is unclear if reorganization of spinal circuitry post-injury affects the modular organization. Here we characterize the modular synergy organization of locomotor muscle activity expressed during assisted stepping in subjects with complete and incomplete spinal cord injury (SCI) of varying chronicity, before any explicit training regimen. We also investigated whether the synergy characteristics changed in two subjects who achieved independent walking after training with spinal cord epidural stimulation.

Methods

To capture synergy structures during stepping, individuals with SCI were stepped on a body-weight supported treadmill with manual facilitation, while electromyography (EMGs) were recorded from bilateral leg muscles. EMGs were analyzed using non-negative matrix factorization (NMF) and independent component analysis (ICA) to identify synergy patterns. Synergy patterns from the SCI subjects were compared across different clinical characteristics and to non-disabled subjects (NDs).

Results

Results for both NMF and ICA indicated that the subjects with SCI were similar among themselves, but expressed a greater variability in the number of synergies for criterion variance capture compared to NDs, and weaker correlation to NDs. ICA yielded a greater number of muscle synergies than NMF. Further, the clinical characteristics of SCI subjects and chronicity did not predict any significant differences in the spatial synergy structures despite any neuroplastic changes. Further, post-training synergies did not become closer to ND synergies in two individuals.

Discussion

These findings suggest fundamental differences between motor modules expressed in SCIs and NDs, as well as a striking level of spatial and temporal synergy stability in motor modules in the SCI population, absent the application of specific interventions.

Training with noninvasive brain-machine interface, tactile feedback, and locomotion to enhance neurological recovery in individuals with complete paraplegia: a randomized pilot study

In recent years, our group and others have reported multiple cases of consistent neurological recovery in people with spinal cord injury (SCI) following a protocol that integrates locomotion training with brain machine interfaces (BMI). The primary objective of this pilot study was to compare the neurological outcomes (motor, tactile, nociception, proprioception, and vibration) in both an intensive assisted locomotion training (LOC) and a neurorehabilitation protocol integrating assisted locomotion with a noninvasive brain-machine interface (L + BMI), virtual reality, and tactile feedback. We also investigated whether individuals with chronic-complete SCI could learn to perform leg motor imagery. We ran a parallel two-arm randomized pilot study; the experiments took place in São Paulo, Brazil. Eight adults sensorimotor-complete (AIS A) (all male) with chronic (> 6 months) traumatic spinal SCI participated in the protocol that was organized in two blocks of 14 weeks of training and an 8-week follow-up. The participants were allocated to either the LOC group (n = 4) or L + BMI group (n = 4) using block randomization (blinded outcome assessment). We show three important results: (i) locomotion training alone can induce some level of neurological recovery in sensorimotor-complete SCI, and (ii) the recovery rate is enhanced when such locomotion training is associated with BMI and tactile feedback (∆Mean Lower Extremity Motor score improvement for LOC =  + 2.5, L + B =  + 3.5; ∆Pinprick score: LOC =  + 3.75, L + B =  + 4.75 and ∆Tactile score LOC =  + 4.75, L + B =  + 9.5). (iii) Furthermore, we report that the BMI classifier accuracy was significantly above the chance level for all participants in L + B group. Our study shows potential for sensory and motor improvement in individuals with chronic complete SCI following a protocol with BMIs and locomotion therapy. We report no dropouts nor adverse events in both subgroups participating in the study, opening the possibility for a more definitive clinical trial with a larger cohort of people with SCI.Trial registration: http://www.ensaiosclinicos.gov.br/ identifier RBR-2pb8gq.

A scoping review on the effect of cannabis on pain intensity in people with spinal cord injury

CONTEXT

This scoping review examines the current research on the effect of cannabis upon pain intensity in spinal cord injury (SCI) pain. Chronic pain is a significant secondary condition following SCI, and traditional treatments (e.g. opioids, NSAIDs) are often criticized for providing inadequate relief. As a result, there is increasing interest in and use of cannabis and cannabinoid-based medications as an alternative means of pain control.

OBJECTIVE

The purpose of this review was to examine the scientific evidence on the effect of cannabis/cannabinoids upon pain intensity in SCI by mapping the current literature.

METHODS

Two hundred and fifty-two studies were identified by searching electronic databases for articles published through February 2020. In addition, reviewers scanned the reference lists of identified articles and examined clinicaltrials.gov for unpublished data in this area. Title, abstract, and full-text reviews were completed by two independent reviewers. Data extraction was performed by a single reviewer and verified by a second reviewer.

RESULTS

Six articles covering five treatment studies were included. Studies yielded mixed findings likely due to large variability in methodology, including lack of standardized dosing paradigms, modes of use, and duration of trial.

CONCLUSIONS

The current quality and level of evidence is insufficient to draw reliable conclusions of the efficacy of cannabis upon SCI-related pain itensity. We identify specific limitations of past studies and present guidelines for future research.Trial registration: ClinicalTrials.gov identifier: Nct01606202..

Surface EMG in Subacute and Chronic Care after Traumatic Spinal Cord Injuries

Background: Traumatic spinal cord injury (SCI) is a devastating condition commonly originating from motor vehicle accidents or falls. Trauma care after SCI is challenging; after decompression surgery and spine stabilization, the first step is to assess the location and severity of the traumatic lesion. For this, clinical outcome measures are used to quantify the residual sensation and volitional control of muscles below the level of injury. These clinical assessments are important for decision-making, including the prediction of the recovery potential of individuals after the SCI. In clinical care, this quantification is usually performed using sensation and motor scores, a semi-quantitative measurement, alongside the binary classification of the sacral sparing (yes/no). Objective: In this perspective article, I review the use of surface EMG (sEMG) as a quantitative outcome measurement in subacute and chronic trauma care after SCI. Methods: Here, I revisit the main findings of two comprehensive scoping reviews recently published by our team on this topic. I offer a perspective on the combined findings of these scoping reviews, which integrate the changes in sEMG with SCI and the use of sEMG in neurorehabilitation after SCI. Results: sEMG provides a complimentary assessment to quantify the residual control of muscles with great sensitivity and detail compared to the traditional clinical assessments. Our scoping reviews unveiled the ability of the sEMG assessment to detect discomplete lesions (muscles with absent motor scores but present sEMG). Moreover, sEMG is able to measure the spontaneous activity of motor units at rest, and during passive maneuvers, the evoked responses with sensory or motor stimulation, and the integrity of the spinal cord and descending tracts with motor evoked potentials. This greatly complements the diagnostics of the SCI in the subacute phase of trauma care and deepens our understanding of neurorehabilitation strategies during the chronic phase of the traumatic injury. Conclusions: sEMG offers important insights into the neurophysiological factors underlying sensorimotor impairment and recovery after SCIs. Although several qualitative or semi-quantitative outcome measures determine the level of injury and the natural recovery after SCIs, using quantitative measures such as sEMG is promising. Nonetheless, there are still several barriers limiting the use of sEMG in the clinical environment and a need to advance high-density sEMG technology.

Evaluating prehospital care of patients with potential traumatic spinal cord injury: scoping review

PURPOSE

To gain insight into current research regarding prehospital care (PHC) in patients with potential traumatic spinal cord injury (TSCI) and to disseminate the findings to the research community.

METHODS

In March 2019, we performed a literature search of publications from January 1990 to March 2019 indexed in PubMed, gray literature including professional websites; and reference sections of selected articles for other relevant literature. This review was performed according to Arksey and O'Malley's framework.

RESULTS

There were 42 studies selected based on the inclusion criteria for review; 18 articles regarding immobilization; 12 articles regarding movement, positioning and transport; four for spinal clearance; three for airway protection; and two for the role of PHC providers. There were some articles that covered two topics: one article was regarding movement, positioning and transport and airway protection, and two were regarding spinal clearance and the role of PHC providers.

CONCLUSION

There was no uniform opinion about spinal immobilization of patients with suspected TSCI. The novel lateral trauma position and one of two High Arm IN Endangered Spine (HAINES) methods are preferred methods for unconscious patients. Controlled self-extrication for patients with stable hemodynamic status is recommended. Early and proper identifying of potential TSCI by PHC providers can significantly improve patients' outcomes and can result in avoiding unwanted spinal immobilization. Future prospective studies with a large sample size in real-life settings are needed to provide clear and evidence-based data in PHC of patients with suspected TSCI.

The effect of extracorporeal shock wave therapy in acute traumatic spinal cord injury on motor and sensory function within 6 months post-injury: a study protocol for a two-arm three-stage adaptive, prospective, multi-center, randomized, blinded, placebo-controlled clinical trial

Background

The pathological mechanism in acute spinal cord injury (SCI) is dual sequential: the primary mechanical lesion and the secondary injury due to a cascade of biochemical and pathological changes initiated by the primary lesion. Therapeutic approaches have focused on modulating the mechanisms of secondary injury. Despite extensive efforts in the treatment of SCI, there is yet no causal, curative treatment approach available.

Extracorporeal shock wave therapy (ESWT) has been successfully implemented in clinical use. Biological responses to therapeutic shock waves include altered metabolic activity of various cell types due to direct and indirect mechanotransduction leading to improved migration, proliferation, chemotaxis, modulation of the inflammatory response, angiogenesis, and neovascularization, thus inducing rather a regeneration than repair.

The aim of this clinical study is to investigate the effect of ESWT in humans within the first 48 h after an acute traumatic SCI, with the objective to intervene in the secondary injury phase in order to reduce the extent of neuronal loss.

Methods

This two-arm three-stage adaptive, prospective, multi-center, randomized, blinded, placebo-controlled study has been initiated in July 2020, and a total of 82 patients with acute traumatic SCI will be recruited for the first stage in 15 participating hospitals as part of a two-armed three-stage adaptive trial design. The focused ESWT (energy flux density: 0.1–0.19 mJ/mm², frequency: 2–5 Hz) is applied once at the level of the lesion, five segments above/below, and on the plantar surface of both feet within the first 48 h after trauma.

The degree of improvement in motor and sensory function after 6 months post-injury is the primary endpoint of the study. Secondary endpoints include routine blood chemistry parameters, the degree of spasticity, the ability to walk, urological function, quality of life, and the independence in everyday life.

Discussion

The application of ESWT activates the nervous tissue regeneration involving a multitude of various biochemical and cellular events and leads to a decreased neuronal loss. ESWT might contribute to an improvement in the treatment of acute traumatic SCI in future clinical use.

Trial registration

ClinicalTrials.govNCT04474106

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-022-06161-8.

Hypothermia Therapy for Traumatic Spinal Cord Injury: An Updated Review

Although hypothermia has shown to protect against ischemic and traumatic neuronal death, its potential role in neurologic recovery following traumatic spinal cord injury (TSCI) remains incompletely understood. Herein, we systematically review the safety and efficacy of hypothermia therapy for TSCI. The English medical literature was reviewed using PRISMA guidelines to identify preclinical and clinical studies examining the safety and efficacy of hypothermia following TSCI. Fifty-seven articles met full-text review criteria, of which twenty-eight were included. The main outcomes of interest were neurological recovery and postoperative complications. Among the 24 preclinical studies, both systemic and local hypothermia significantly improved neurologic recovery. In aggregate, the 4 clinical studies enrolled 60 patients for treatment, with 35 receiving systemic hypothermia and 25 local hypothermia. The most frequent complications were respiratory in nature. No patients suffered neurologic deterioration because of hypothermia treatment. Rates of American Spinal Injury Association (AIS) grade conversion after systemic hypothermia (35.5%) were higher when compared to multiple SCI database control studies (26.1%). However, no statistical conclusions could be drawn regarding the efficacy of hypothermia in humans. These limited clinical trials show promise and suggest therapeutic hypothermia to be safe in TSCI patients, though its effect on neurological recovery remains unclear. The preclinical literature supports the efficacy of hypothermia after TSCI. Further clinical trials are warranted to conclusively determine the effects of hypothermia on neurological recovery as well as the ideal means of administration necessary for achieving efficacy in TSCI.

Biomechanical differences between able-bodied and spinal cord injured individuals walking in an overground robotic exoskeleton

Background

Robotic assisted gait training (RAGT) uses a powered exoskeleton to support an individual’s body and move their limbs, with the aim of activating latent, pre-existing movement patterns stored in the lower spinal cord called central pattern generators (CPGs) to facilitate stepping. The parameters that directly stimulate the stepping CPGs (hip extension and ipsilateral foot unloading) should be targeted to maximise the rehabilitation benefits of these devices.

Aim

To compare the biomechanical profiles of individuals with a spinal cord injury (SCI) and able-bodied individuals inside the ReWalk^TM powered exoskeleton and to contrast the users’ profiles with the exoskeleton.

Methods

Eight able-bodied and four SCI individuals donned a ReWalk^TM and walked along a 12-meter walkway, using elbow crutches. Whole-body kinematics of the users and the ReWalk^TM were captured, along with GRF and temporal-spatial characteristics. Discreet kinematic values were analysed using a Kruskall-Wallis H and Dunn’s post-hoc analysis. Upper-body differences, GRF and temporal-spatial characteristics were analysed using a Mann-Whitney U test (P<0.05).

Results

Walking speed ranged from 0.32–0.39m/s. Hip abduction, peak knee flexion and ankle dorsiflexion for both the SCI and able-bodied groups presented with significant differences to the ReWalk^TM. The able-bodied group presented significant differences to the ReWalk^TM for all kinematic variables except frontal plane hip ROM (P = 0.093,δ = -0.56). Sagittal plane pelvic and trunk ROM were significantly greater in the SCI vs. able-bodied (P = 0.004,δ = -1; P = 0.008,δ = -0.94, respectively). Posterior braking force was significantly greater in the SCI group (P = 0.004, δ = -1).

Discussion

The different trunk movements used by the SCI group and the capacity for the users’ joint angles to exceed those of the device suggest that biomechanical profiles varied according to the user group. However, upright stepping with the ReWalk^TM device delivered the appropriate afferent stimulus to activate CPGs as there were no differences in key biomechanical parameters between the two user groups.

Spinal cord stimulation research in the restoration of motor, sensory and autonomic function for individuals living with spinal cord injuries: A scoping review

OBJECTIVE

To describe the status of spinal cord stimulation (SCS) research for the improvement of motor, sensory and autonomic function for individuals living with a spinal cord injury (SCI).

DATA SOURCES

This scoping review identified original research published prior to March 31, 2021, via literature searches using Medline, EMBASE, PubMed, Science Direct, CINAHL, Sport Discus, Web of Science, as well as a targeted search for well-known principal investigators. Search terms included permutations of "spinal cord stimulation", "epidural spinal cord stimulation", "transcutaneous spinal cord stimulation", "magnetic spinal cord stimulation" and "neuromodulation".

STUDY SELECTION

Studies were included if they: 1) were in English, 2) presented original research on humans living with a SCI, and 3) investigated at least one of the three forms of SCS.

DATA EXTRACTION

Extracted data included: authors, publication year, participant characteristics, purpose, study design, stimulation (device, location, parameters,) primary outcomes, and adverse events.

DATA SYNTHESIS

As a scoping review the extracted data was tabulated and presented descriptively. Themes and gaps in the literature were identified and reported. Of the 5,754 articles screened, 103 articles were included (55 epidural, 36 transcutaneous and 12 magnetic). The primary research design was a case study or series with only a single randomized clinical trial. Motor recovery was the most common primary outcome for epidural and transcutaneous SCS studies whereas bowel and bladder outcomes were most common for magnetic. Seventy percent of the studies included 10 or fewer participants, and 18 articles documented at least one adverse event. Incomplete stimulation parameter descriptions were noted across many studies. No articles mentioned direct engagement of consumers or advocacy groups.

CONCLUSION

This review identified a need for more robust study designs, larger sample sizes, comparative studies, improved reporting of stimulation parameters, adverse event data, and alignment of outcomes with the priorities of the SCI community.

Inclusive Trial Designs in Acute Spinal Cord Injuries: Prediction-Based Stratification of Clinical Walking Outcome and Projected Enrolment Frequencies

Background

New therapeutic approaches in neurological disorders are progressing into clinical development. Past failures in translational research have underlined the critical importance of selecting appropriate inclusion criteria and primary outcomes. Narrow inclusion criteria provide sensitivity, but increase trial duration and cost to the point of infeasibility, while broader requirements amplify confounding, increasing the risk of trial failure. This dilemma is perhaps most pronounced in spinal cord injury (SCI), but applies to all neurological disorders with low frequency and/or heterogeneous clinical manifestations.

Objective

Stratification of homogeneous patient cohorts to enable the design of clinical trials with broad inclusion criteria.

Methods

Prospectively–gathered data from patients with acute cervical SCI were analysed using an unbiased recursive partitioning conditional inference tree (URP–CTREE) approach. Performance in the 6-minute walk test at 6 months after injury was classified based on standardized neurological assessments within the first 15 days of injury. Functional and neurological outcomes were tracked throughout rehabilitation up to 6 months after injury.

Results

URP–CTREE identified homogeneous outcome cohorts in a study group of 309 SCI patients. These cohorts were validated by an internal, yet independent, validation group of 172 patients. The study group cohorts identified demonstrated distinct recovery profiles throughout rehabilitation. The baseline characteristics of the analysed groups were compared to a reference group of 477 patients.

Conclusion

URP–CTREE enables inclusive trial design by revealing the distribution of outcome cohorts, discerning distinct recovery profiles and projecting potential patient enrolment by providing estimates of the relative frequencies of cohorts to improve the design of clinical trials in SCI and beyond.

A NEW SCORE BASED ON THE INTERNATIONAL STANDARDS FOR NEUROLOGICAL CLASSIFICATION OF SPINAL CORD INJURY FOR INTEGRATIVE EVALUATION OF CHANGES IN SENSORIMOTOR FUNCTIONS

Sensorimotor function of patients with spinal cord injury (SCI) is commonly assessed according to the International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI). From the ISNCSCI segmental motor and sensory assessments, upper and lower extremity motor scores (UEMS and LEMS), sum scores of pin prick (PP) and light touch (LT) sensation, the neurological level of injury (NLI) and the classification of lesion severity according to the American Spinal Injury Association Impairment Scale (AIS) grade are derived. Changes of these parameters over time are widely used to evaluate neurological recovery. However, evaluating recovery based on a single ISNCSCI scoring or classification variable may misestimate overall recovery. Here, we propose an Integrated Neurological Change Score (INCS) based on the combination of normalized changes between two-time points of UEMS, LEMS, and total PP and LT scores. To assess the agreement of INCS with clinical judgement of meaningfulness of neurological changes, changes of ISNCSCI variables between two time-points of 88 patients from an independent cohort were rated by 20 clinical experts according to a 5-categories Likert Scale. As for individual ISNCSCI variables, neurological change measured by INCS is associated to severity (AIS grade), age and time since injury, but INCS better reflects clinical judgment about meaningfulness of neurological changes than individual ISNCSCI variables. In addition, INCS is related with changes in functional independence measured by the Spinal Cord Independence Measure (SCIM) in patients with tetraplegia. INCS may be a useful measure of overall neurological change in clinical studies.

Pursuing More Aggressive Timelines in the Surgical Treatment of Traumatic Spinal Cord Injury (TSCI): A Retrospective Cohort Study with Subgroup Analysis

Background: The optimal timing of surgical therapy for traumatic spinal cord injury (TSCI) remains unclear. The purpose of this study is to evaluate the impact of “ultra-early” (<4 h) versus “early” (4–24 h) time from injury to surgery in terms of the likelihood of neurologic recovery. Methods: The effect of surgery on neurological recovery was investigated by comparing the assessed initial and final values of the American Spinal Injury Association (ASIA) Impairment Scale (AIS). A post hoc analysis was performed to gain insight into different subgroup regeneration behaviors concerning neurological injury levels. Results: Datasets from 69 cases with traumatic spinal cord injury were analyzed. Overall, 19/46 (41.3%) patients of the “ultra-early” cohort saw neurological recovery compared to 5/23 (21.7%) patients from the “early” cohort (p = 0.112). The subgroup analysis revealed differences based on the neurological level of injury (NLI) of a patient. An optimal cutpoint for patients with a cervical lesion was estimated at 234 min. Regarding the prediction of neurological improvement, sensitivity was 90.9% with a specificity of 68.4%, resulting in an AUC (area under the curve) of 84.2%. In thoracically and lumbar injured cases, the estimate was lower, ranging from 284 (thoracic) to 245 min (lumbar) with an AUC of 51.6% and 54.3%. Conclusions: Treatment within 24 h after TSCI is associated with neurological recovery. Our hypothesis that intervention within 4 h is related to an improvement in the neurological outcome was not confirmed in our collective. In a clinical context, this suggests that after TSCI there is a time frame to get the right patient to the right hospital according to advanced trauma life support (ATLS) guidelines.

Limited changes in locomotor recovery and unaffected white matter sparing after spinal cord contusion at different times of day

The circadian gene expression rhythmicity drives diurnal oscillations of physiological processes that may determine the injury response. While outcomes of various acute injuries are affected by the time of day at which the original insult occurred, such influences on recovery after spinal cord injury (SCI) are unknown. We report that mice receiving moderate, T9 contusive SCI at ZT0 (zeitgeber time 0, time of lights on) and ZT12 (time of lights off) showed similar hindlimb function recovery in the Basso mouse scale (BMS) over a 6 week post-injury period. In an independent study, no significant differences in BMS were observed after SCI at ZT18 vs. ZT6. However, the ladder walking test revealed modestly improved performance for ZT18 vs. ZT6 mice at week 6 after injury. Consistent with those minor effects on functional recovery, terminal histological analysis revealed no significant differences in white matter sparing at the injury epicenter. Likewise, blood-spinal cord barrier disruption and neuroinflammation appeared similar when analyzed at 1 week post injury at ZT6 or ZT18. Therefore, locomotor recovery after thoracic contusive SCI is not substantively modulated by the time of day at which the neurotrauma occurred.

Characterizing Natural Recovery of People With Initial Motor Complete Tetraplegia

OBJECTIVE

To determine the differences in neurologic recovery in persons with initial cervical American Spinal Cord Injury Association Impairment Scale (AIS) grades A and B over time.

DESIGN

Retrospective analysis of data from people with traumatic cervical spinal cord injury (SCI) enrolled in the National Spinal Cord Injury Model Systems (SCIMS) database from 2011-2019.

SETTING

SCIMS centers.

PARTICIPANTS

Individuals (N=187) with traumatic cervical (C1-C7 motor level) SCI admitted with initial AIS grade A and B injuries within 30 days of injury, age 16 years or older, upper extremity motor score (UEMS) ≤20 on both sides, and complete neurologic data at admission and follow-up between 6 months and 2 years.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Conversion in AIS grades, UEMS and lower extremity motor scores (LEMS), and sensory scores.

RESULTS

Mean time to initial and follow-up examinations were 16.1±7.3 days and 377.5±93.4 days, respectively. Conversion from an initial cervical AIS grades A and B to motor incomplete status was 13.4% and 50.0%, respectively. The mean UEMS change for people with initial AIS grades A and B did not differ (7.8±6.5 and 8.8±6.1; P=.307), but people with AIS grade B experienced significantly higher means of LEMS change (2.3±7.4 and 8.8±13.9 (P≤.001). The increased rate of conversion to motor incomplete status from initial AIS grade B appears to be the primary driving factor of increased overall motor recovery. Individuals with initial AIS grade B had greater improvement in sensory scores.

CONCLUSIONS

While UEMS recovery is similar in persons with initial AIS grades A and B, the rate of conversion to motor incomplete status, LEMS, and sensory recovery are significantly different. This information is important for clinical as well as research considerations.

Rehabilitation of Acute Vs. Chronic Patients With Spinal Cord Injury With a Neurologically Controlled Hybrid Assistive Limb Exoskeleton: Is There a Difference in Outcome?

This study aimed to assess the outcome of acute and chronic participants with spinal cord injury (SCI) after 12 weeks of bodyweight supported treadmill training (BWSTT) with a hybrid assistive limb exoskeleton (HAL). Acute participants were defined as ≤12 months between SCI and training, chronic participants >12 months between SCI and training. We assessed whether HAL-assisted BWSTT is advantageous for acute and chronic participants and if length of time post injury impacts the outcome of HAL-assisted BWSTT. As the primary outcome, we assessed the time needed for the 10 meter walk test (10MWT). Hundred and twenty-one individuals participated in a 12-week HAL-assisted BWSTT five times a week. We regularly conducted a 10MWT, a 6 minute walk test (6MWT), and assessed the walking index for spinal cord injury (WISCI II) and lower extremity motor score (LEMS) to evaluate the gait performance without the exoskeleton. Distance and time were recorded by the treadmill while the participant was walking with the exoskeleton. All participants benefit from the 12-week HAL-assisted BWSTT. A significant difference between acute and chronic participants' outcomes was found in 6MWT, LEMS, and WISCI II, though not in 10MWT. Although chronic participants improved significantly lesser than acute participants, they did improve their outcome significantly compared to the beginning. Hybrid assistive limb-assisted BWSTT in the rehabilitation of patients with SCI is advantageous for both acute and chronic patients. We could not define a time related cut-off threshold following SCI for effectiveness of HAL-assisted BWSTT.

Pros and Cons of Early and Very Early Surgery for Traumatic Central Cord Syndrome with Spinal Stenosis: Literature Review and Case Report

BACKGROUND

 The case of a 69-year-old patient with an acute traumatic central cord syndrome (ATCCS) with preexisting spinal stenosis raised a discussion over the question of conservative versus surgical treatment in the acute setting. We provide a literature overview on the management (conservative vs. surgical treatment) of ATCCS with preexisting spinal stenosis.

METHODS

 We reviewed the literature concerning essential concepts for the management of ATCCS with spinal stenosis and cervical spinal cord injury. The data retrieved from these studies were applied to the potential management of an illustrative case report.

RESULTS

 Not rarely has ATCCS an unpredictable neurologic course because of its dynamic character with secondary injury mechanisms within the cervical spinal cord in the early phase, the possibility of functional deterioration, and the appearance of a neuropathic pain syndrome during late follow-up. The result of the literature review favors early surgical treatment in ATCCS patients with preexisting cervical stenosis.

CONCLUSION

 Reluctance toward aggressive and timely surgical treatment of ATCCS should at least be questioned in patients with preexisting spinal stenosis.

Consensus Guidelines for Improving Quality of Assessment and Training for Neuromuscular Diseases

Critical components of successful evaluation of clinical outcome assessments (COAs) in multisite clinical trials and clinical practice are standardized training, administration, and documented reliability of scoring. Experiences of evaluators, alongside patient differences from regional standards of care, may contribute to heterogeneity in clinical center's expertise. Achieving low variability and high reliability of COA is fundamental to clinical research and to give confidence in our ability to draw rational, interpretable conclusions from the data collected. The objective of this manuscript is to provide a framework to guide the learning process for COAs for use in clinics and clinical trials to maximize reliability and validity of COAs in neuromuscular disease (NMD). This is a consensus-based guideline with contributions from fourteen leading experts in clinical outcomes and the field of clinical outcome training in NMD. This framework should guide reliable and valid assessments in NMD specialty clinics and clinical trials. This consensus aims to expedite study start up with a progressive training pathway ranging from research naïve to highly experienced clinical evaluators. This document includes recommendations for education guidelines and roles and responsibilities of key stakeholders in COA assessment and implementation to ensure quality and consistency of outcome administration across different settings.

Effect of Early vs Delayed Surgical Treatment on Motor Recovery in Incomplete Cervical Spinal Cord Injury With Preexisting Cervical Stenosis: A Randomized Clinical Trial

IMPORTANCE

The optimal management for acute traumatic cervical spinal cord injury (SCI) is unknown.

OBJECTIVE

To determine whether early surgical decompression results in better motor recovery than delayed surgical treatment in patients with acute traumatic incomplete cervical SCI associated with preexisting canal stenosis but without bone injury.

DESIGN, SETTING, AND PARTICIPANTS

This multicenter randomized clinical trial was conducted in 43 tertiary referral centers in Japan from December 2011 through November 2019. Patients aged 20 to 79 years with motor-incomplete cervical SCI with preexisting canal stenosis (American Spinal Injury Association [ASIA] Impairment Scale C; without fracture or dislocation) were included. Data were analyzed from September to November 2020.

INTERVENTIONS

Patients were randomized to undergo surgical treatment within 24 hours after admission or delayed surgical treatment after at least 2 weeks of conservative treatment.

MAIN OUTCOMES AND MEASURES

The primary end points were improvement in the mean ASIA motor score, total score of the spinal cord independence measure, and the proportion of patients able to walk independently at 1 year after injury.

RESULTS

Among 72 randomized patients, 70 patients (mean [SD] age, 65.1 [9.4] years; age range, 41-79 years; 5 [7%] women and 65 [93%] men) were included in the full analysis population (37 patients assigned to early surgical treatment and 33 patients assigned to delayed surgical treatment). Of these, 56 patients (80%) had data available for at least 1 primary outcome at 1 year. There was no significant difference among primary end points for the early surgical treatment group compared with the delayed surgical treatment group (mean [SD] change in ASIA motor score, 53.7 [14.7] vs 48.5 [19.1]; difference, 5.2; 95% CI, -4.2 to 14.5; P = .27; mean [SD] SCIM total score, 77.9 [22.7] vs 71.3 [27.3]; P = .34; able to walk independently, 21 of 30 patients [70.0%] vs 16 of 26 patients [61.5%]; P = .51). A mixed-design analysis of variance revealed a significant difference in the mean change in ASIA motor scores between the groups (F1,49 = 4.80; P = .03). The early surgical treatment group, compared with the delayed surgical treatment group, had greater motor scores than the delayed surgical treatment group at 2 weeks (mean [SD] score, 34.2 [18.8] vs 18.9 [20.9]), 3 months (mean [SD] score, 49.1 [15.1] vs 37.2 [20.9]), and 6 months (mean [SD] score, 51.5 [13.9] vs 41.3 [23.4]) after injury. Adverse events were common in both groups (eg, worsening of paralysis, 6 patients vs 6 patients; death, 3 patients vs 3 patients).

CONCLUSIONS AND RELEVANCE

These findings suggest that among patients with cervical SCI, early surgical treatment produced similar motor regain at 1 year after injury as delayed surgical treatment but showed accelerated recovery within the first 6 months. These exploratory results suggest that early surgical treatment leads to faster neurological recovery, which requires further validation.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01485458; umin.ac.jp/ctr Identifier: UMIN000006780.

Protocol for rapid onset of mobilisation in patients with traumatic spinal cord injury (PROMPT-SCI) study: a single-arm proof-of-concept trial of early in-bed leg cycling following acute traumatic spinal cord injury

INTRODUCTION

Activity-based therapy (ABT) is an important aspect of rehabilitation following traumatic spinal cord injury (SCI). Unfortunately, it has never been adapted to acute care despite compelling preclinical evidence showing that it is safe and effective for promoting neurological recovery when started within days after SCI. This article provides the protocol for a study that will determine the feasibility and explore potential benefits of early ABT in the form of in-bed leg cycling initiated within 48 hours after the end of spinal surgery for SCI.

METHODS AND ANALYSIS

PROMPT-SCI (protocol for rapid onset of mobilisation in patients with traumatic SCI) is a single-site single-arm proof-of-concept trial. Forty-five patients aged 18 years or older with a severe traumatic SCI (American Spinal Injury Association Impairment Scale grade A, B or C) from C0 to L2 undergoing spinal surgery within 48 hours of the injury will be included. Participants will receive daily 30 min continuous sessions of in-bed leg cycling for 14 consecutive days, initiated within 48 hours of the end of spinal surgery. The feasibility outcomes are: (1) absence of serious adverse events associated with cycling, (2) completion of 1 full session within 48 hours of spinal surgery for 90% of participants and (3) completion of 11 sessions for 80% of participants. Patient outcomes 6 weeks and 6 months after the injury will be measured using neurofunctional assessments, quality of life questionnaires and inpatient length of stay. Feasibility and patient outcomes will be analysed with descriptive statistics. Patient outcomes will also be compared with a matched historical cohort that has not undergone in-bed cycling using McNemar and Student's t-tests for binary and continuous outcomes, respectively.

ETHICS AND DISSEMINATION

PROMPT-SCI is approved by the Research Ethics Board of the CIUSSS NIM. Recruitment began in April 2021. Dissemination strategies include publications in scientific journals and presentations at conferences.

TRIAL REGISTRATION NUMBER

NCT04699474.

Deep brain stimulation for locomotion in incomplete human spinal cord injury (DBS-SCI): protocol of a prospective one-armed multi-centre study

INTRODUCTION

Spinal cord injury (SCI) is a devastating condition with immediate impact on the individual's health and quality of life. Major functional recovery reaches a plateau 3-4 months after injury despite intensive rehabilitative training. To enhance training efficacy and improve long-term outcomes, the combination of rehabilitation with electrical modulation of the spinal cord and brain has recently aroused scientific interest with encouraging results. The mesencephalic locomotor region (MLR), an evolutionarily conserved brainstem locomotor command and control centre, is considered a promising target for deep brain stimulation (DBS) in patients with SCI. Experiments showed that MLR-DBS can induce locomotion in rats with spinal white matter destructions of >85%.

METHODS AND ANALYSIS

In this prospective one-armed multi-centre study, we investigate the safety, feasibility, and therapeutic efficacy of MLR-DBS to enable and enhance locomotor training in severely affected, subchronic and chronic American Spinal Injury Association Impairment Scale C patients in order to improve functional recovery. Patients undergo an intensive training programme with MLR-DBS while being regularly followed up until 6 months post-implantation. The acquired data of each timepoint are compared with baseline while the primary endpoint is performance in the 6-minute walking test. The clinical trial protocol was written in accordance with the Standard Protocol Items: Recommendations for Interventional Trials checklist.

ETHICS AND DISSEMINATION

This first in-man study investigates the therapeutic potential of MLR-DBS in SCI patients. One patient has already been implanted with electrodes and underwent MLR stimulation during locomotion. Based on the preliminary results which promise safety and feasibility, recruitment of further patients is currently ongoing. Ethical approval has been obtained from the Ethical Committee of the Canton of Zurich (case number BASEC 2016-01104) and Swissmedic (10000316). Results will be published in peer-reviewed journals and presented at conferences.

TRIAL REGISTRATION NUMBER

NCT03053791.

Time-to-enrollment in clinical trials investigating neurological recovery in chronic spinal cord injury: observations from a systematic review and ClinicalTrials.gov database

Currently, large numbers of clinical trials are performed to investigate different forms of experimental therapy for patients suffering from chronic spinal cord injury (SCI). However, for the enrollment process, there are different views on how the time period between injury and interventions should be determined. Herein, we sought to evaluate the impact of time-to-enrollment in chronic SCI clinical trials. A data set comprising 957 clinical studies from clinicalTrials.gov was downloaded and analyzed focusing on the eligibility criteria for post-injury time-to-enrollment. We also aggregated individual patient data from nine clinical trials of regenerative interventions for chronic SCI selected by a systematic literature search from 1990 to 2018. Characteristics of the studies were assessed and compared by dividing into three groups based on time-to-enrollment (group 1 ≤ 12 months, group 2 = 12–23 months and group 3 ≥ 24 months). In ClinicalTrials.gov registry, 445 trials were identified for chronic SCI where 87% (385) were unrestricted in the maximum post-injury time for trial eligibility. From systematic literature search, nine studies and 156 patients (group 1 = 30, group 2 = 55 and group 3 = 71) were included. The range of time-to-enrollment was 0.5 to 321 months in those studies. We also observed various degrees of motor and sensory improvement in between three time-to-enrollment groups. Our results indicate that enrolling wide ranges of time-to-enrollment in a group may present imprecise outcomes. Clinical trial designs should consider appropriate post-injury time frames to evaluate therapeutic benefit.

Epidural spinal cord stimulation for motor recovery in spinal cord injury: A systematic review

BACKGROUND

Epidural spinal cord stimulation (ESCS) emerged as a technology for eliciting motor function in the 1990's and was subsequently employed therapeutically in the population with spinal cord injury (SCI). Despite a considerable number of ESCS studies, a comprehensive systematic review of ESCS remains unpublished.

OBJECTIVE

The current review of the existing literature evaluated the efficacy of ESCS for improving motor function in individuals with SCI.

METHODS

A search for ESCS studies was performed using the following databases: Medline (Ovid), Web of Science and Embase. Furthermore, to maximize results, an inverse manual search of references cited by identified articles was also performed. Studies published between January 1995 and June 2020 were included. The search was constructed around the following key terms: Spinal cord stimulation, SCI and motor response generation.

RESULTS

A total of 3435 articles were initially screened, of which 18 met the inclusion criteria. The total sample comprised of 24 participants with SCI. All studies reported some measure of improvement in motor activity with ESCS, with 17 reporting altered EMG responses. Functional improvements were reported in stepping (n = 11) or muscle force (n = 4). Only 5 studies assessed ASIA scale pre- and post-intervention, documenting improved classification in 4 of 11 participants. Appraisal using the modified Downs and Black quality checklist determined that reviewed studies were of poor quality. Due to heterogeneity of outcome measures utilized in studies reviewed, a meta-analysis of data was not possible.

CONCLUSION

While the basic science is encouraging, the therapeutic efficacy of ESCS remains inconclusive.

Reliability and validity of the international standards for neurological classification of spinal cord injury in patients with non-traumatic spinal cord lesions

STUDY DESIGN

Prospective, observational study.

OBJECTIVES

The International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI) represent the gold standard for the assessment of patients with spinal cord injury (SCI) and their measurement properties have been evaluated in patients with traumatic lesions. Albeit the ISNCSCI are widely used also for the assessment and prognosis of patients with non-traumatic SCI, a validation of this grading system in this sample has never been performed. Therefore, the aim of this study is to evaluate the measurement properties of the ISNCSCI in a population of persons with non-traumatic SCI.

SETTING

Three Italian rehabilitation hospitals.

METHODS

The sample included 140 patients with non-traumatic SCI of different etiology, level and grade, for a total of 169 evaluations performed by two examiners. Cronbach's Alpha was used to evaluate the internal consistency of the ISNCSCI various components. The agreement between two examiners of each center in the definition of different components was used to assess the inter-rater reliability. The construct validity was evaluated through the correlation of the ISNCSCI with the Spinal Cord Independence Measure (SCIM).

RESULTS

The ISNCSCI showed substantial internal consistency, and substantial inter-rater agreement for AIS grade, cumulative motor and sensory scores. The motor scores for upper and lower extremity showed fair to moderate correlation with SCIM self-care and motility subscores, respectively. The ISNCSCI total motor score correlated with the total SCIM score.

CONCLUSIONS

Our study demonstrates that the ISNCSCI are a valid and reliable tool for the assessment of patients with non-traumatic SCI.

Early Predictors of Neurological Outcomes After Traumatic Spinal Cord Injury: A Systematic Review and Proposal of a Conceptual Framework

BACKGROUND

Neurological outcomes after traumatic spinal cord injury are variable and depend on patient-, trauma-, and treatment-related factors as well as on spinal cord injury characteristics, imaging, and biomarkers.

OBJECTIVE

The aims of the study were to identify and classify the early predictors of neurological outcomes after traumatic spinal cord injury.

DATA SOURCES

The Medline, PubMed, Embase, and the Cochrane Central Database were searched using medical subject headings. The search was extended to the reference lists of identified studies.

STUDY ELIGIBILITY CRITERIA

The study eligibility criteria were assessment of neurological outcomes as primary or secondary outcome, predictors collected during the acute phase after traumatic spinal cord injury, and multivariate design.

PARTICIPANTS

The participants were adult patients with traumatic spinal cord injury followed at least 3 mos after injury.

STUDY APPRAISAL AND SYNTHESIS METHODS

The quality of studies was assessed by two independent reviewers using the Study Quality Assessment Tools for Observational Cohort and Cross-sectional Studies. The studies' narrative synthesis relied on a classification of the predictors according to quantity, quality, and consistency of the evidence. Results were summarized in a conceptual framework.

RESULTS

Forty-nine articles were included. The initial severity of traumatic spinal cord injury (American Spinal Injury Association Impairment Scale, motor score, and neurological level of injury) was the strongest predictor of neurological outcomes: patients with more severe injury at admission presented poor neurological outcomes. Intramedullary magnetic resonance imaging signal abnormalities were also associated with neurological outcomes, as the presence of intramedullary hemorrhage was a factor of poor prognosis. Other largely studied predictors, such as age and surgical timing, showed some inconsistency in results depending on cutoffs. Younger age and early surgery were generally associated with good outcomes. Although widely studied, other factors, such as vertebral and associated injuries, failed to show association with outcomes. Cerebrospinal fluid inflammatory biomarkers, as emerging factors, were significantly associated with outcomes.

CONCLUSIONS

This study provides a comprehensive review of predictors of neurological outcomes after traumatic spinal cord injury. It also highlights the heterogeneity of outcomes used by studies to assess neurological recovery. The proposed conceptual framework classifies predictors and illustrates their relationships with outcomes.

Revisiting the Examination of Sharp/Dull Discrimination as Clinical Measure of Spinothalamic Tract Integrity

Objective: Revisiting the sharp/dull discrimination as clinical measure of spinothalamic tract function considering the International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI). Three clinically relevant factors were evaluated as to their impact on reliability: (1) the localization of dermatomes in relation to the sensory level, (2) the examination tool, and (3) the threshold of correct answers for grading of a preserved sharp/dull discrimination.

Design: Prospective monocentric psychometric study.

Setting: Spinal Cord Injury Center, Heidelberg University Hospital, Germany.

Participants: Convenient sample of 21 individuals with subacute spinal cord injury (age: 31–82 years) and 20 individuals without spinal cord injury (age: 24–63 years).

Assessment: All participants underwent three assessments for sharp/dull discrimination, applying five commonly used examination tools in seven dermatomes, performed by three trained examiners under conditions in accordance with ISNCSCI.

Main Outcome Measures: Assessment of interrater reliability by determining both the Fleiss kappa (κ) coefficient and the percentage agreement between raters. Data were dichotomized regarding the ISNCSCI threshold.

Results: Interrater reliability in individuals with SCI was overall substantial (κ = 0.68; CI 0.679–0.681) and moderate (κ = 0.54; CI 0.539–0.543) in dermatomes below the sensory level. All applied tools led to at least moderate reliability below the sensory level (lowest κ = 0.44; CI 0.432–0.440), with the officially endorsed safety pin achieving the highest (substantial) reliability (κ = 0.64; CI 0.638–0.646). Percentage agreement differed between non-SCI (97.3%) and formally intact above level dermatomes in SCI (89.2%).

Conclusions: Sharp/dull discrimination as a common clinical examination technique for spinothalamic tract function is a reliable assessment. Independent from the used examination tools, reliability was substantial, with the medium-sized safety pin delivering the most favorable results. Notwithstanding this, all other tools could be considered if a safety pin is not available. Regarding interrater reliability and guessing probability, a threshold of 80% correct responses for preserved sharp/dull discrimination appears to be most suitable, which is in line with current clinical approaches and ISNCSCI. The causal attribution of the identified differences in sharp/dull discrimination between clinically intact dermatomes of individuals with SCI and unaffected dermatomes of individuals without SCI requires future work.

Clinical Trial Registration Number (German Clinical Trials Register): DRKS00015334 (https://www.drks.de).

Long term outcome of functional independence and quality of life after traumatic SCI in Germany

STUDY DESIGN

Multicenter observational study.

OBJECTIVE

To describe the long-term outcome of functional independence and quality of life (QoL) for individuals with traumatic and ischemic SCI beyond the first year after injury.

SETTING

A multicenter study in Germany.

METHODS

Participants of the European multicenter study about spinal cord injury (EMSCI) of three German SCI centers were included and followed over time by the German spinal cord injury cohort study (GerSCI). Individuals' most recent spinal cord independence measure (SCIM) scores assessed by a clinician were followed up by a self-report (SCIM-SR) and correlated to selected items of the WHO short survey of quality of life (WHO-QoL-BREF).

RESULTS

Data for 359 individuals were obtained. The average time passed the last clinical SCIM examination was 81.47 (SD 51.70) months. In total, 187 of the 359 received questionnaires contained a completely evaluable SCIM-SR. SCIM scores remained stable with the exception of reported management of bladder and bowel resulting in a slight decrease of SCIM-SR of -2.45 points (SD 16.81). SCIM-SR scores showed a significant correlation with the selected items of the WHO-QoL-BREF (p < 0.01) with moderate to strong influence.

CONCLUSION

SCIM score stability over time suggests a successful transfer of acquired independence skills obtained during primary rehabilitation into the community setting paralleled by positively related QoL measurements but bladder and bowel management may need special attention.

A taxonomy for consistent handling of conditions not related to the spinal cord injury (SCI) in the International Standards for Neurological Classification of SCI (ISNCSCI)

STUDY DESIGN

Committee consensus process including additional structured feedback from spinal cord injury (SCI) experts attending a focus group workshop.

OBJECTIVES

To define a taxonomy for standardized documentation of non-SCI-related conditions in the International Standards for Neurological Classification of SCI (ISNCSCI).

SETTING

Americal Spinal Injury Association (ASIA) International Standards Committee with 16 international ISNCSCI experts.

METHODS

With the new taxonomy, not-normal sensory or motor scores should be tagged with an asterisk ("*"), if they are impacted by a non-SCI condition such as burns, casts, joint contractures, peripheral nerve injuries, amputations, pain, or generalized weakness. The non-SCI condition and instructions on how to handle the "*"-tagged scores during classification should be detailed in the comments box. While sum scores are always calculated based on examined scores, classification variables such as the neurological level of injury (NLI) or the ASIA Impairment Scale (AIS) grades are tagged with an "*", when they have been determined on the basis of clinical assumptions.

RESULTS

With the extended "*"-tag concept, sensory and motor examination results impacted by non-SCI conditions above, at, or below the NLI can be consistently documented, scored, and classified. Feedback from workshop participants confirms agreement on its clinical relevance, logic and soundness, easiness of understanding, communicability, and applicability in daily work.

CONCLUSIONS

After multiple internal revisions, a taxonomy for structured documentation of conditions superimposed on the impairments caused by the SCI together with guidelines for consistent scoring and classification was released with the 2019 ISNCSCI revision. This taxonomy is intended to increase the accuracy of ISNCSCI classifications.

An Overview of Spinal Injuries due to Dive or Fall into Shallow Water: Our Long-Term, Double-Center Experience from the Aegean Coast

Purpose

We aimed to evaluate the demographic and clinical features of patients with cervical spinal injuries secondary to shallow-water diving and share our therapeutic outcomes.

Methods

A retrospective study was carried out using data extracted from the medical files of 39 patients (3 females and 36 males) who were treated surgically (n = 29) or conservatively (n = 10). Demographics, clinical features, operative data, American Spine Injury Association (ASIA) impairment scales, and Karnofsky Performance Status (KPS) results were noted.

Results

The average age of our series (n = 39) was 31.59 ± 14.80 (range, 14 to 92) years. The vast majority of patients (n = 34, 87.2%) presented with isolated cervical trauma. At initial admission, neurological deficits were diagnosed in 22 (56.4%) patients. A single-level cervical involvement was noted in 18 (46.2%) patients, while 21 cases (53.8%) displayed injury involving multiple levels. The levels of cervical injury were C5 (n = 16, 41%), C6 (n = 11, 28.2%), C7 (n = 6, 15.4%), C1 (n = 5, 12.8%), and C4 (n = 1, 2.6%). A total of 22 patients had neurological deficits at admission. Surgery was performed using anterior (n = 21, 72.4%), posterior (n = 7, 24.1%), and combined anterior and posterior (n = 1, 3.4%) routes. Nine patients (23.1%) exhibited improvement in their neurological deficits. There were significant improvements in both the ASIA impairment scale and KPS results after treatment.

Conclusion

Our data indicated that dive- or fall-related cervical spinal injuries are associated with profound morbidity. Reinforcement of primary prevention, identification of target population, and increased awareness on this topic are the key steps to minimize the frequency and severity of complications and to optimize therapeutic outcomes.

Characterizing Natural Recovery after Traumatic Spinal Cord Injury

The predominant tool used to predict outcomes after traumatic spinal cord injury (SCI) is the International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI), in association with the American Spinal Injury Association (ASIA) Impairment Scale (AIS). These measures have evolved based on analyses of large amounts of longitudinal neurological recovery data published in numerous separate studies. This article reviews and synthesizes published data on neurological recovery from multiple sources, only utilizing data in which the sacral sparing definition was applied for determination of completeness. Conversion from a complete to incomplete injury is more common in tetraplegia than paraplegia. The majority of AIS conversion and motor recovery occurs within the first 6-9 months, with the most rapid rate of motor recovery occurring in the first three months after injury. Motor score changes, as well as recovery of motor levels, are described with the initial strength of muscles as well as the levels of the motor zone of partial preservation influencing the prognosis. Total motor recovery is greater for patients with initial AIS B than AIS A, and greater after initial AIS C than with motor complete injuries. Older age has a negative impact on neurological and functional recovery after SCI; however, the specific age (whether >50 or >65 years) and underlying reasons for this impact are unclear. Penetrating injury is more likely to lead to a classification of a neurological complete injury compared with blunt trauma and reduces the likelihood of AIS conversion at one year. There are insufficient data to support gender having a major effect on neurological recovery after SCI.

Use of Regression Tree Analysis for Predicting the Functional Outcome after Traumatic Spinal Cord Injury

Predicting the long-term functional outcome after traumatic spinal cord injury (TSCI) is needed to adapt medical strategies and plan an optimized rehabilitation. This study investigates the use of regression trees for the development of predictive models based on acute clinical and demographic predictors. This prospective study was performed on 172 patients hospitalized after TSCI. Functional outcome was quantified using the Spinal Cord Independence Measure (SCIM) collected within the first-year post-injury. Age, delay before surgery, and Injury Severity Score (ISS) were considered as continuous predictors whereas energy of injury, trauma mechanisms, neurological level of injury, injury severity, occurrence of early spasticity, urinary tract infection, pressure ulcer, and pneumonia were coded as categorical inputs. A simplified model was built using only American Spinal Injury Association Impairment Scale grade, neurological level, energy, and age as predictor and was compared to a more complex model considering all 11 predictors mentioned above. The models built using 4 and 11 predictors were found to explain 51.4% and 62.3% of the variance of the SCIM total score after validation, respectively. Severity of the neurological deficit at admission was found to be the most important predictor. Other important predictors were the ISS, age, neurological level, and delay before surgery. Regression trees offer promising performances for predicting the functional outcome after a TSCI. It could help to determine the number and type of predictors leading to a prediction model of the functional outcome that can be used clinically in the future.

Unbiased Recursive Partitioning Enables Robust and Reliable Outcome Prediction in Acute Spinal Cord Injury

Neurological disorders usually present very heterogeneous recovery patterns. Nonetheless, accurate prediction of future clinical end-points and robust definition of homogeneous cohorts are necessary for scientific investigation and targeted care. For this, unbiased recursive partitioning with conditional inference trees (URP-CTREE) have received increasing attention in medical research, especially, but not limited to traumatic spinal cord injuries (SCIs). URP-CTREE was introduced to SCI as a clinical guidance tool to explore and define homogeneous outcome groups by clinical means, while providing high accuracy in predicting future clinical outcomes. The validity and predictive value of URP-CTREE to provide improvements compared with other more common approaches applied by clinicians has recently come under critical scrutiny. Therefore, a comprehensive simulation study based on traumatic, cervical complete spinal cord injuries provides a framework to investigate and quantify the issues raised. First, we assessed the replicability and robustness of URP-CTREE to identify homogeneous subgroups. Second, we implemented a prediction performance comparison of URP-CTREE with traditional statistical techniques, such as linear or logistic regression, and a novel machine learning method. URP-CTREE's ability to identify homogeneous subgroups proved to be replicable and robust. In terms of prediction, URP-CTREE yielded a high prognostic performance comparable to a machine learning algorithm. The simulation study provides strong evidence for the robustness of URP-CTREE, which is achieved without compromising prediction accuracy. The slightly lower prediction performance is offset by URP-CTREE's straightforward interpretation and application in clinical settings based on simple, data-driven decision rules.

Granulocyte colony-stimulating factor in traumatic spinal cord injury

Granulocyte colony-stimulating factor (G-CSF) is a cytokine used in pharmaceutical preparations for the treatment of chemotherapy-induced neutropenia. Evidence from experimental studies indicates that G-CSF exerts relevant activities in the central nervous system (CNS) in particular after lesions. In acute, subacute, and chronic CNS lesions, G-CSF appears to have strong anti-inflammatory, antiapoptotic, antioxidative, myelin-protective, and axon-regenerative activities. Additional effects result in the stimulation of angiogenesis and neurogenesis as well as in bone marrow stem cell mobilization to the CNS. There are emerging preclinical and clinical data indicating that G-CSF is a safe and effective drug for the treatment of acute and chronic traumatic spinal cord injury (tSCI), which we summarize in this review.

Updated Review: The Steroid Controversy for Management of Spinal Cord Injury

BACKGROUND

Acute spinal cord injury (ASCI) is a devastating event that can have a profound impact on the lives of patients and their families. While no definitive medical treatment exists, the role of methylprednisolone (MP) in the management of ASCI and other spinal cord pathologies has been investigated in depth; however, its use remains contentious. While MP initially showed promise in the efficacy of ASCI treatment, more recent studies have questioned its use citing numerous systemic adverse effects. Pharmacologic treatments in this area are poorly understood due to the scarcity of knowledge surrounding the pathophysiology and heterogeneity of patients presenting with these conditions. Despite these shortcomings and due to the lack of alternative treatment options, MP is still widely used by physicians.

METHODS

We review prior and current literature on the use of MP treatment for ASCI patients with a discussion of novel drug delivery systems that have demonstrated the potential to improve MP's bioavailability at the site of injury while minimizing systemic side effects. In addition, current views on the role of MP and dexamethasone in metastatic spinal cord compression and postoperative infection are reviewed.

RESULTS

While some data support benefits in the use of steroids on spinal cord pathology, extensive research suggests at best limited effects and an unresolvable risk/benefit problem.

CONCLUSIONS

At present, evidence regarding use of dexamethasone for MSCC is contentious, especially regarding dose regiments. Ultimately, further investigation into the use of steroids is required to determine its utility in treating patients with spinal cord pathology.

Neurophysiological Changes in the First Year After Cell Transplantation in Sub-acute Complete Paraplegia

Neurophysiological testing can provide quantitative information about motor, sensory, and autonomic system connectivity following spinal cord injury (SCI). The clinical examination may be insufficiently sensitive and specific to reveal evolving changes in neural circuits after severe injury. Neurophysiologic data may provide otherwise imperceptible circuit information that has rarely been acquired in biologics clinical trials in SCI. We reported a Phase 1 study of autologous purified Schwann cell suspension transplantation into the injury epicenter of participants with complete subacute thoracic SCI, observing no clinical improvements. Here, we report longitudinal electrophysiological assessments conducted during the trial. Six participants underwent neurophysiology screening pre-transplantation with three post-transplantation neurophysiological assessments, focused on the thoracoabdominal region and lower limbs, including MEPs, SSEPs, voluntarily triggered EMG, and changes in GSR. We found several notable signals not detectable by clinical exam. In all six participants, thoracoabdominal motor connectivity was detected below the clinically assigned neurological level defined by sensory preservation. Additionally, small voluntary activations of leg and foot muscles or positive lower extremity MEPs were detected in all participants. Voluntary EMG was most sensitive to detect leg motor function. The recorded MEP amplitudes and latencies indicated a more caudal thoracic level above which amplitude recovery over time was observed. In contrast, further below, amplitudes showed less improvement, and latencies were increased. Intercostal spasms observed with EMG may also indicate this thoracic “motor level.” Galvanic skin testing revealed autonomic dysfunction in the hands above the injury levels. As an open-label study, we can establish no clear link between these observations and cell transplantation. This neurophysiological characterization may be of value to detect therapeutic effects in future controlled studies.

Prognostic value of early leukocyte fluctuations for recovery from traumatic spinal cord injury

BACKGROUND

Acute traumatic spinal cord injury (SCI) induces a systemic immune response involving circulating white blood cells (WBCs). How this response is influenced by overall trauma severity, the neurological level of injury and/or correlates with patient outcomes is poorly understood. The objective of this study was to identify relationships between early changes in circulating WBCs, injury characteristics and long-term patient outcomes in individuals with traumatic SCI.

METHODS

We retrospectively analysed data from 161 SCI patients admitted to Brisbane's Princess Alexandra Hospital (exploration cohort). Logistic regression models in conjunction with receiver operating characteristic (ROC) analyses were used to assess the strength of specific links between the WBC response, respiratory infection incidence and neurological outcomes (American Spinal Injury Association Impairment Scale (AIS) grade conversion). An independent validation cohort from the Trauma Hospital Berlin, Germany (n = 49) was then probed to assess the robustness of effects and disentangle centre effects.

RESULTS

We find that the extent of acute neutrophilia in human SCI patients is positively correlated with New Injury Severity Scores but inversely with the neurological outcome (AIS grade). Multivariate analysis demonstrated that acute SCI-induced neutrophilia is an independent predictor of AIS grade conversion failure, with an odds ratio (OR) of 4.16 and ROC area under curve (AUC) of 0.82 (P < 0.0001). SCI-induced lymphopenia was separately identified as an independent predictor of better recovery (OR = 24.15; ROC AUC = 0.85, P < 0.0001). Acute neutrophilia and increased neutrophil-lymphocyte ratios were otherwise significantly associated with respiratory infection presentation in both patient cohorts.

CONCLUSIONS

Our findings demonstrate the prognostic value of modelling early circulating neutrophil and lymphocyte counts with patient characteristics for predicting the longer term recovery after SCI.

Corticospinal-motor neuronal plasticity promotes exercise-mediated recovery in humans with spinal cord injury

Rehabilitative exercise in humans with spinal cord injury aims to engage residual neural networks to improve functional recovery. We hypothesized that exercise combined with non-invasive stimulation targeting spinal synapses further promotes functional recovery. Twenty-five individuals with chronic incomplete cervical, thoracic, and lumbar spinal cord injury were randomly assigned to 10 sessions of exercise combined with paired corticospinal-motor neuronal stimulation (PCMS) or sham-PCMS. In an additional experiment, we tested the effect of PCMS without exercise in 13 individuals with spinal cord injury with similar characteristics. During PCMS, 180 pairs of stimuli were timed to have corticospinal volleys evoked by transcranial magnetic stimulation over the primary motor cortex arrive at corticospinal-motor neuronal synapses of upper- or lower-limb muscles (depending on the injury level), 1-2 ms before antidromic potentials were elicited in motor neurons by electrical stimulation of a peripheral nerve. Participants exercised for 45 min after all protocols. We found that the time to complete subcomponents of the Graded and Redefined Assessment of Strength, Sensibility and Prehension (GRASSP) and the 10-m walk test decreased on average by 20% after all protocols. However, the amplitude of corticospinal responses elicited by transcranial magnetic stimulation and the magnitude of maximal voluntary contractions in targeted muscles increased on overage by 40-50% after PCMS combined or not with exercise but not after sham-PCMS combined with exercise. Notably, behavioural and physiological effects were preserved 6 months after the intervention in the group receiving exercise with PCMS but not in the group receiving exercise combined with sham-PCMS, suggesting that the stimulation contributed to preserve exercise gains. Our findings indicate that targeted non-invasive stimulation of spinal synapses might represent an effective strategy to facilitate exercise-mediated recovery in humans with different degrees of paralysis and levels of spinal cord injury.

Neuroprosthetics: an outlook on active challenges toward clinical adoption

Neural prostheses are designed to counter the effects of neurotrauma and restore the fundamental building blocks of human experience including motor action, sensation, and meaningful communication with other individuals. Here, we present an overview of active avenues, open questions, and debated topics in neuroprosthetics, such as targeting the mechanisms of sensorimotor recovery and designing brain interfaces for scalability. We review leading opinions in this thriving field, aiming to inform translational practice toward clinical adoption.

Theoretical and practical training improves knowledge of the examination guidelines of the International Standards for Neurological Classification of Spinal Cord Injury

Study design

Prospective pre–post study.

Objectives

International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI) represents the most frequently used assessment to determine the level and severity of a spinal cord injury (SCI). The guidelines for ISNCSCI are complex and challenging. Knowledge of its correct execution needs to be imparted precisely. The aim of this study was to investigate whether hands-on instructional courses can increase the knowledge of the ISNCSCI examination guidelines.

Setting

European Multicenter Study about SCI.

Methods

Before and after the instructional courses, participants were asked to complete questionnaires. The set of questions covered the most important aspects of the examination guidelines. Attendees were asked to self-rate their occupation and experience in ISNCSCI.

Results

The comparison of pretest and posttest results of 164 attendees from 2014 to 2018 revealed an improvement of knowledge reflected by an increase of correct answers from 66 ± 17% before to 89 ± 11% after the course (p < 0.01). The improvement was not associated with occupation (p > 0.1). However, the correctness of pretest results differed concerning both the period of experience with ISNCSCI (p < 0.05) and the course language (p < 0.01), while the frequency of execution resulted in differences in the posttest (p = 0.01).

Conclusions

Instructional courses substantially improve knowledge of the ISNCSCI examination guidelines. Differences in knowledge present before the course leveled off after the course. Comprehensive theoretical training is strongly recommended to ensure reliability and validity of ISNCSCI examinations in clinical routine and research. Albeit being practiced in the instructional courses, the benefit of hands-on training still needs to be systematically evaluated in future studies.

Association of timing of gabapentinoid use with motor recovery after spinal cord injury

OBJECTIVE

To explore the hypothesis that earlier administration of acute gabapentinoids is beneficial to motor recovery after spinal cord injury in humans.

METHODS

This is an observational study using a cohort from the European Multi-Centre Study about Spinal Cord Injury. Patient charts were reviewed to extract information regarding the administration and timing of gabapentinoid anticonvulsants. The primary outcome measure was motor scores, as measured by the International Standards for Neurological Classification of Spinal Cord Injury, collected longitudinally in the first year after injury. Sensory scores (light touch and pinprick) and functional measures (Spinal Cord Independence Measure) were secondary outcomes. Linear mixed effects regression models included a drug-by-time interaction to determine whether exposure to gabapentinoids altered recovery of muscle strength in the first year after injury.

RESULTS

A total of 201 participants were included in the study and had a median age of 46 and baseline motor score of 50. Participants were mostly men (85%) with sensory and motor complete injuries (50%). Seventy individuals (35%) were administered gabapentinoids within the first 30 days after injury, and presented with similar demographics. In the longitudinal model, the administration of gabapentinoids within 30 days after injury was associated with improved motor recovery when compared to those who did not receive gabapentinoids during this time (3.69 additional motor points from 4 to 48 weeks after injury; p = 0.03). This effect size increased as administration occurred earlier after injury (i.e., a benefit of 4.68 points when administered within 5 days).

CONCLUSIONS

This retrospective, observational study provided evidence of the beneficial effect of gabapentinoid anticonvulsants on motor recovery after spinal cord injury. More critically, it highlighted a potential time dependence, suggesting that earlier intervention is associated with better outcomes.

CLASSIFICATION OF EVIDENCE

This study provides Class IV evidence that gabapentinoids improve motor recovery for individuals with acute spinal cord injury.