Incidence of traumatic spinal cord injury worldwide: A systematic review, data integration, and update

Clinical Applications and Future Translation of Somatosensory Neuroprostheses

Somatosensory neuroprostheses restore, replace, or enhance tactile and proprioceptive feedback for people with sensory impairments due to neurological disorders or injury. Somatosensory neuroprostheses typically couple sensor inputs from a wearable device, prosthesis, robotic device, or virtual reality system with electrical stimulation applied to the somatosensory nervous system via noninvasive or implanted interfaces. While prior research has mainly focused on technology development and proof-of-concept studies, recent acceleration of clinical studies in this area demonstrates the translational potential of somatosensory neuroprosthetic systems. In this review, we provide an overview of neurostimulation approaches currently undergoing human testing and summarize recent clinical findings on the perceptual, functional, and psychological impact of somatosensory neuroprostheses. We also cover current work toward the development of advanced stimulation paradigms to produce more natural and informative sensory feedback. Finally, we provide our perspective on the remaining challenges that need to be addressed prior to translation of somatosensory neuroprostheses.

A national cross-sectional survey on community spinal cord injury individuals profiles, health-related quality of life and support services in China: implications for healthcare and rehabilitation

BACKGROUND

Spinal cord injury (SCI) results in severe, permanent functional changes and has become a global health priority due to its high incidence, cost, and disability rate. Current national epidemiological data on SCI in China are limited and outdated. This study aimed to provide a comprehensive, national cross-sectional investigation of SCI epidemiology in China.

METHODS

This cross-sectional study included 3055 SCI participants aged 8 to 78 years, conducted from May to September 2023. Data collected encompassed demographic characteristics, employment status, etiology, years lived with disability (YLD), family structure, caregiving status, income, health insurance, paralysis type, and health-related quality of life (HRQoL). Descriptive statistics analyses were used to assess demographic and injury characteristics. Group differences were assessed using t-tests, one-way ANOVA and Chi-square tests. Significant factors were examined using multivariate regression analysis.

RESULTS

The majority (88.9%) of respondents were aged 15 to 59 years, with a male-to-female ratio of 2.36:1. Car accidents caused 45.4% of tetraplegia cases, falls caused 35.9% of paraplegia cases, and myelitis was the leading cause of non-traumatic SCI. Among paraplegia participants, 65.5% had complete SCI, while 53.1% of tetraplegia participants had incomplete SCI. Functional improvement was reported by 9.58% of participants. Half (50.3%) of the respondents were unemployed, and 75% had incomes below the national average. HRQoL was significantly lower in the SCI population compared to controls, mainly influenced by injury site, income, age and etiology (p < 0.05).

CONCLUSIONS

SCI participants in China exhibit low HRQoL and reemployment rates. Accessible community and vocational rehabilitation programs, alongside robust public medical services, are essential for enhancing reemployment and HRQoL among SCI participants, reducing the overall disease burden.

Traumatic spinal cord injury and its correlation to risk of autoimmune/-inflammatory disease

STUDY DESIGN

Nationwide epidemiological open cohort study.

OBJECTIVES

To evaluate whether individuals with traumatic spinal cord injury (TSCI) are more prone to develop autoimmune diseases compared to a general non-TSCI population.

SETTING

Danish public national registries.

METHODS

An open nationwide cohort, including individuals born in Denmark from or alive during 1945-2018 was collected and the study period was 1980-2018. Poissons Log-linear regression estimated the incidence rate ratio (IRR) for developing eight groups of autoimmune diseases. A dose-response relationship based on the cervical/thoracic level of injury was assessed by stratification.

RESULTS

The cohort included 3,272 individuals with TSCI and 4.8 million background individuals, accounting for 50,865 and 140 million person-years respectively. The TSCI population had an overall IRR of 1.81 (95% CI, 1.59 to 2.05) of getting any autoimmune disease. Subgroup analysis found positive associations for; a) Other neurologic IRR 5.19 (95% CI, 2.79 to 9.65), b) multiple sclerosis IRR 3.70 (95% CI, 2.54 to 5.40), c) Dermatologic IRR 2.57 (95% CI, 1.86 to 3.55), d) Type 1 diabetes mellitus IRR 2.01 (95% CI, 1.54 to 2.61), e) Systemic 1.92 (95% CI, 1.44 to 2.55), and f) Gastroenterologic IRR 1.42 (95% CI, 1.05 to 1.92). Cervical levels of TSCI showed an IRR of 1.70 (95% CI, 1.43 to 2.02), while thoracic levels had an IRR 1.98 (95% CI, 1.63 to 2.39).

CONCLUSIONS

TSCI may be an individual risk factor of developing an autoimmune disease. There does not appear to exist a dose-response relationship from the level of injury.

SPONSORSHIP

None.

Structural Functions of 3D-Printed Polymer Scaffolds in Regulating Cell Fates and Behaviors for Repairing Bone and Nerve Injuries

Tissue repair and regeneration, such as bone and nerve restoration, face significant challenges due to strict regulations within the immune microenvironment, stem cell differentiation, and key cell behaviors. The development of 3D scaffolds is identified as a promising approach to address these issues via the efficiently structural regulations on cell fates and behaviors. In particular, 3D-printed polymer scaffolds with diverse micro-/nanostructures offer a great potential for mimicking the structures of tissue. Consequently, they are foreseen as promissing pathways for regulating cell fates, including cell phenotype, differentiation of stem cells, as well as the migration and the proliferation of key cells, thereby facilitating tissue repairs and regenerations. Herein, the roles of structural functions of 3D-printed polymer scaffolds in regulating the fates and behaviors of numerous cells related to tissue repair and regeneration, along with their specific influences are highlighted. Additionally, the challenges and outlooks associated with 3D-printed polymer scaffolds with various structures for modulating cell fates are also discussed.

HISTOLOGICAL COMPARISON OF REPEATED MILD WEIGHT DROP AND LATERAL FLUID PERCUSSION INJURY MODELS OF TRAUMATIC BRAIN INJURY IN FEMALE AND MALE RATS

ABSTRACT

In preclinical traumatic brain injury (TBI) research, the animal model should be selected based on the research question and outcome measures of interest. Direct side-by-side comparisons of different injury models are essential for informing such decisions. Here, we used immunohistochemistry to compare the outcomes from two common models of TBI, lateral fluid percussion (LFP) and repeated mild weight drop (rmWD) in adult female and male Wistar rats. Specifically, we measured the effects of LFP and rmWD on markers of cerebrovascular and tight junction disruption, neuroinflammation, mature neurons, and perineuronal nets in the cortical site of injury, cortex adjacent to injury, dentate gyrus, and the CA 2/3 area of the hippocampus. Animals were randomized into the LFP or rmWD group. On day 1, the LFP group received a craniotomy, and on day 4, injury (or sham procedure; randomly assigned). The rmWD animals underwent either injury or isoflurane only (randomly assigned) on each of those 4 days. Seven days after injury, brains were harvested for analysis. Overall, our observations revealed that the most significant disruptions were evident in response to LFP, followed by craniotomy only, whereas rmWD animals showed the least residual changes compared with isoflurane-only controls, supporting consideration of rmWD as a mild injury. LFP led to longer-lasting disruptions, perhaps more representative of moderate TBI. We also report that craniotomy and LFP produced greater disruptions in females relative to males. These findings will assist the field in the selection of animal models based on target severity of postinjury outcomes and support the inclusion of both sexes and appropriate control groups.

Harnessing Artificial Neural Networks for Spinal Cord Injury Prognosis

Background: Prediction of neurorehabilitation outcomes after a Spinal Cord Injury (SCI) is crucial for healthcare resource management and improving prognosis and rehabilitation strategies. Artificial neural networks (ANNs) have emerged as a promising alternative to conventional statistical approaches for identifying complex prognostic factors in SCI patients. Materials: a database of 1256 SCI patients admitted for rehabilitation was analyzed. Clinical and demographic data and SCI characteristics were used to predict functional outcomes using both ANN and linear regression models. The former was structured with input, hidden, and output layers, while the linear regression identified significant variables affecting outcomes. Both approaches aimed to evaluate and compare their accuracy for rehabilitation outcomes measured by the Spinal Cord Independence Measure (SCIM) score. Results: Both ANN and linear regression models identified key predictors of functional outcomes, such as age, injury level, and initial SCIM scores (correlation with actual outcome: R = 0.75 and 0.73, respectively). When also alimented with parameters recorded during hospitalization, the ANN highlighted the importance of these additional factors, like motor completeness and complications during hospitalization, showing an improvement in its accuracy (R = 0.87). Conclusions: ANN seemed to be not widely superior to classical statistics in general, but, taking into account complex and non-linear relationships among variables, emphasized the impact of complications during the hospitalization on recovery, particularly respiratory issues, deep vein thrombosis, and urological complications. These results suggested that the management of complications is crucial for improving functional recovery in SCI patients.

Global incidence and characteristics of spinal cord injury since 2000-2021: a systematic review and meta-analysis

BACKGROUND

This study employs systematic review and meta-analysis to explore the incidence and characteristics of spinal cord injury (SCI) between 2000 and 2021, aiming to provide the most recent and comprehensive data support for the prevention, diagnosis, treatment, and care of SCI.

METHODS

Systematic searches were conducted on epidemiological studies of SCI published between January 1, 2000, and March 29, 2024. Meta-analysis, subgroup analysis, meta-regression, publication bias detection, and literature quality assessment were extensively utilized.

RESULTS

The pooled results from 229 studies indicated that the overall incidence rate of SCI was 23.77 (95% CI, 21.50-26.15) per million people, with traumatic spinal cord injuries (TSCI) at a rate of 26.48 (95% CI, 24.15-28.93) per million people, and non-traumatic spinal cord injuries (NTSCI) at a rate of 17.93 (95% CI, 13.30-23.26) per million people. The incidence of TSCI exhibited a marked age-related increase and was significantly higher in community settings compared to hospital and database sources. Males experienced TSCI at a rate 3.2 times higher than females. Between 2000 and 2021, the incidence of TSCI remained consistently high, between 20 and 45 per million people, whereas NTSCI incidence has seen a steady rise since 2007, stabilizing at a high rate of 25-35 per million people. Additionally, the incidence of TSCI in developing countries was notably higher than that in developed countries. There were significant differences in the causes of injury, severity, injury segments, gender, and age distribution among the TSCI and NTSCI populations, but the proportion of male patients was much higher than that of female patients. Moreover, study quality, country type, and SCI type contributed to the heterogeneity in the meta-analysis.

CONCLUSIONS

The incidence rates of different types of SCI remain high, and the demographic distribution of SCI patients is changing, indicating a serious disease burden on healthcare systems and affected populations. These findings underscore the necessity of adopting targeted preventive, therapeutic, and rehabilitative measures based on the incidence and characteristics of SCI.

Development of a regional-based predictive model of incidence of traumatic spinal cord injury using machine learning algorithms

Objective

To develop a predictive model of incidence of traumatic spinal cord injury (TSCI).

Methods

The data for training the model included both the incidence data and the covariates. The incidence data were extracted from systematic reviews and the covariates were extracted from data available in the international road federation database. Then the feature processing measures were taken. First we defined a hyper-parameter, missing-value threshold, in order to eliminate features that exceed this threshold. To tackle the problem of overfitting of model we determined the Pearson correlation of features and excluded those with more than 0.7 correlation. After feature selection three different models including simple linear regression, support vector regression, and multi-layer perceptron were examined to fit the purposes of this study. Finally, we evaluated the model based on three standard metrics: Mean Absolute Error, Root Mean Square Error, and R2.

Results

Our machine-learning based model could predict the incidence rate of TSCI with the mean absolute error of 4.66. Our model found "Vehicles in use, Total vehicles/Km of roads", "Injury accidents/100 Million Veh-Km", "Vehicles in use, Vans, Pick-ups, Lorries, Road Tractors", "Inland surface Passengers Transport (Mio Passenger-Km), Rail", and "% paved" as top predictors of transport-related TSCI (TRTSCI).

Conclusions

Our model is proved to have a high accuracy to predict the incidence rate of TSCI for countries, especially where the main etiology of TSCI is related to road traffic injuries. Using this model, we can help the policymakers for resource allocation and evaluation of preventive measures.

[Specialized Concepts for the Management of Severe Neurotrauma]

Neurotrauma results from violence on structures of the central or peripheral nervous system and is a clinically common disease entity with high relevance for patients' long-term outcome. The application of evidence-based diagnostic and therapeutic concepts aims to minimize secondary injury and thus to improve treatment outcome. This article describes the current management of the two main injury patterns of neurotrauma - traumatic brain and spinal cord injury.

Cervical misalignment in motorcyclists in relation to new helmet removal recommendations shown with augmented reality resources: A biomechanical analysis

Objective

The aim of this study is to determine the best technique and position for helmet removal in injured motorcyclists by comparing cervical misalignment produced in the supine position and prone position.

Method

Comparative cross-sectional clinical simulation study to quantify CM using biomechanical analysis with the use of inertial systems. The main variable was determined for the flexion-extension motion. The extraction was tested for both positions (prone position and supine position), which were repeated 3 times for each of the 30 volunteers included, and the movement from the initial neutral position was also determined, resulting in a total of 270 biomechanical studies.

Results

A flexion was observed when moving the patient from the neutral position to the SP, due to the size of the helmet, of 1.29° ± 5.12°. Helmet removal in the supine position resulted in an average flexion-extension range of 17.51° ± 6.49°, while the same extraction in prone position recorded an average range of 10.82° ± 8.05°. For the main variable, statistically significant differences were found when comparing prone position and supine position (p = 0.0087).

Conclusions

The main conclusion of the study is that the helmet removal should be done in the position in which we find the patient, whether in prone position or supine position. Additionally, the new technique described for the prone position causes less movement of the cervical spine than the usual supine position.

Increased Risk of Myocardial Infarction, Heart Failure, and Atrial Fibrillation After Spinal Cord Injury

BACKGROUND

Heart diseases are a growing concern for the spinal cord injury (SCI) population.

OBJECTIVES

This study aims to compare the incidence of heart diseases between SCI survivors and the general non-SCI population.

METHODS

We identified 5,083 SCI survivors and 1:3 age- and sex-matched non-SCI controls. Study outcomes were myocardial infarction (MI), heart failure (HF), and atrial fibrillation (AF). The cohort was followed up from the index date (diagnosis date for SCI or corresponding date for matched controls) until 2019.

RESULTS

SCI survivors showed a higher risk for MI (adjusted HR [aHR]: 2.41; 95% CI: 1.93-3.00), HF (aHR: 2.24; 95% CI: 1.95-2.56), and AF (aHR: 1.84; 95% CI: 1.49-2.28) compared to controls. The risks were further increased for those who were registered in the National Disability Registry within 1 year from the index date (SCI survivors with disability): SCI survivors with severe disability had the highest risks of MI (aHR: 3.74; 95% CI: 2.43-5.76), HF (aHR: 3.96; 95% CI: 3.05-5.14), and AF (aHR: 3.32; 95% CI: 2.18-5.05). Cervical and lumbar SCI survivors had an increased risk of heart disease regardless of disability compared to matched controls; these risks were slightly higher in those with disability. Thoracic SCI survivors with disability had significantly increased risk of heart disease compared to matched controls.

CONCLUSIONS

SCI survivors at all levels were at significantly greater risk for heart disease than non-SCI controls, particularly those with severe disability. Clinicians must be aware of the importance of heart disease in SCI survivors.

Neutrophil-to-lymphocyte ratio at admission for early diagnosis, severity assessment, and prognosis of acute traumatic spinal cord injury

STUDY DESIGN

A retrospective study.

OBJECTIVE

This study examined the value of neutrophil-to-lymphocyte ratio at admission for early diagnosis, severity assessment, and prognosis of acute traumatic SCI.

SETTING

The First People's Hospital of Neijiang, China.

METHODS

This was a single-center, retrospective, cohort study of patients treated within 12 h of acute SCI between January 2018 and October 2022. Ninety-four SCI patients were selected as the Observation group, including 26 with complete injury (AIS grade A) and 68 with incomplete injury (AIS grade B-D), while 94 patients with simple spinal fracture were randomly selected as the Control group. Eighty-one observation group patients underwent surgical treatment, of which 33 had a higher AIS grade (Good prognosis subgroup) and 48 a lower or equal grade post-surgery (Poor prognosis subgroup). Univariate and multivariate analyses were performed to assess predictors of early diagnosis, severity, and 6-month outcome.

RESULTS

Initial white blood cell count, neutrophil count, monocyte count, and NLR were higher in the Observation group than the Control group, while lymphocyte count was lower in the Observation group. Multivariate logistic regression analysis identified NLR as an independent predictor of early diagnosis. Spinal canal encroachment ≥50%, neutrophil count, and NLR were higher in the complete injury subgroup, and spinal canal encroachment ≥50% was an independent predictor of complete injury, while NLR was not. The NLR was higher in the poor prognosis subgroup and was an independent risk factor.

CONCLUSIONS

Peripheral blood NLR is useful for early diagnosis of acute SCI and is predictive of clinical outcome.

Improving Outcomes in People with Spinal Cord Injury: Encouraging Results from a Multidisciplinary Advanced Rehabilitation Pathway

Spinal cord injury (SCI) consists of damage to any segment of the spinal cord extending to potential harm to nerves in the cauda equina. Rehabilitative efforts for SCI can involve conventional physiotherapy, innovative technologies, as well as cognitive treatment and psychological support. The aim of this study is to evaluate the feasibility of a dedicated, multidisciplinary, and integrated intervention path for SCI, encompassing both conventional and technological interventions, while observing their impact on cognitive, motor, and behavioral outcomes and the overall quality of life for individuals with SCI. Forty-two patients with SCI were included in the analysis utilizing electronic recovery system data. The treatment regimen included multidisciplinary rehabilitation approaches, such as traditional physiotherapy sessions, speech therapy, psychological support, robotic devices, advanced cognitive rehabilitation, and other interventions. Pre-post comparisons showed a significant improvement in lower limb function (Fugl Meyer Assessment-FMA < 0.001), global cognitive functioning (Montreal Cognitive Assessment-MoCA p < 0.001), and perceived quality of life at both a physical and mental level (Short Form-12-SF-12 p < 0.001). Furthermore, we found a significant reduction in depressive state (Beck Depression Inventory-BDI p < 0.001). In addition, we assessed patient satisfaction using the Short Form of the Patient Satisfaction Questionnaire (PSQ), offering insights into the subjective evaluation of the intervention. In conclusion, this retrospective study provides positive results in terms of improvements in motor function, cognitive functions, and quality of life, highlighting the importance of exploring multidisciplinary approaches.

Analysis of Risk Factors for Postoperative Deep Vein Thrombosis in Traumatic Spinal Fracture Complicated with Spinal Cord Injury

The purpose of this study is to investigate the risk factors for postoperative deep vein thrombosis (DVT) in patients with traumatic spinal fractures complicated with Spinal Cord Injury(SCI). We conducted a retrospective analysis of 110 patients with traumatic spinal fractures and SCI admitted to our hospital from March 2021 to April 2024. DVT was diagnosed using ultrasound. Patient history, general data, surgical data, laboratory tests, and thromboelastogram (TEG) results were collected. The patients were divided into a DVT group and a non-DVT group according to the results of ultrasound one week after surgery. The risk factors and diagnostic value were analyzed using binary logistic regression and receiver operating characteristic (ROC) curves in both univariate and multivariate analyses. Multivariate and ROC analysis results showed that D-dimer, lower extremity, duration of bedrest, and MA values of TEG were independent risk factors for DVT in SCI, with D-dimer having the highest diagnostic value (AUC = 0.883). The AUC values for lower extremity, duration of bedrest, and MA were 0.731, 0.750, and 0.625. In conclusion, Postoperative D-dimer > 5.065 mg/l, lower extremity < 3, duration of bedrest, and MA value of TEG are independent risk factors for postoperative DVT in SCI patients, D-dimer having the highest diagnostic value. When the above risk factors occur, clinicians need to be vigilant and take appropriate prevention and treatment measures.

Management of Cervical Spinal Cord Injury without Major Bone Injury in Adults

The incidence of cervical spinal cord injury (CSCI) without major bone injury is increasing, possibly because older people typically have pre-existing cervical spinal canal stenosis. The demographics, neurological injury, treatment, and prognosis of this type of CSCI differ from those of CSCI with bone or central cord injury. Spine surgeons worldwide are debating on the optimal management of CSCI without major bone injury. Therefore, this narrative review aimed to address unresolved clinical questions related to CSCI without major bone injury and discuss treatment strategies based on current findings. The greatest divide among spine surgeons worldwide hinges on whether surgery is necessary for patients with CSCI without major bone injury. Certain studies have recommended early surgery within 24 h after injury; however, evidence regarding its superiority over conservative treatment remains limited. Delayed MRI may be beneficial; nevertheless, reliable factors and imaging findings that predict functional prognosis during the acute phase and ascertain the necessity of surgery should be identified to determine whether surgery/early surgery is better than conservative therapy/delayed surgery. Quality-of-life assessments, including neuropathic pain, spasticity, manual dexterity, and motor function, should be performed to examine the superiority of surgery/early surgery to conservative therapy/delayed surgery.

Formononetin ameliorates the LPS-induced inflammatory response and apoptosis of neuronal cells via NF-κB/NLRP3 signaling pathway

The objective of this study was to investigate the impact of formononetin on cellular apoptosis and inflammatory responses following spinal cord injury (SCI), as well as the underlying mechanisms involved. In this study, PC12 cells were treated with lipopolysaccharide (LPS) and different concentrations of Formononetin (FT) (50 μM, 100 μM, 200 μM). To confirm the effect of nuclear factor-κB (NF-κB)/NLR family pyrin domain containing 3 (NLRP3) signaling pathways, the cells in the phorbol-12-myristate-13-acetate (PMA) group were treated with 0.1 μmol/L PMA (NF-κB/NLRP3 signaling pathway activators). The lactate dehydrogenase (LDH) concentration and cell viability, proliferating cell nuclear antigen (PCNA) fluorescence intensity, and cell apoptosis were determined using an LDH kit, Cell Counting Kit-8 (CCK-8), immunofluorescence, and flow cytometry assays, respectively. Tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and interleukin-16 (IL-6) expression levels were detected by quantitative ELISA assay. The expression of proteins related to the NF-κB/NLRP3 signaling pathway was detected by western blotting. Our results showed that LPS increased LDH levels in PC12 cells, suggesting that inflammation caused PC12 cell damage. However, the PC12 cell damage was decreased by methylprednisolone. Formononetin promotes cell survival and proliferation, and prevents apoptosis in a concentration-dependent manner. Formononetin reduced the TNF-α, IL-1β, and IL-6 levels in the LPS-treated model. Moreover, formononetin decreased the levels of p-p65 NF-κB and NLRP3 in PC12 cells. We conclude that formononetin ameliorated the inflammatory response and apoptosis in LPS-induced inflammatory injury in neuronal cells via the NF-κB/NLRP3 signaling pathway.

Application of Vagus Nerve Stimulation in Spinal Cord Injury Rehabilitation

Spinal cord injury (SCI) is a prevalent devastating condition causing significant morbidity and mortality, especially in developing countries. The pathophysiology of SCI involves ischemia, neuroinflammation, cell death, and scar formation. Due to the lack of definitive therapy for SCI, interventions mainly focus on rehabilitation to reduce deterioration and improve the patient's quality of life. Currently, rehabilitative exercises and neuromodulation methods such as functional electrical stimulation, epidural electrical stimulation, and transcutaneous electrical nerve stimulation are being tested in patients with SCI. Other spinal stimulation techniques are being developed and tested in animal models. However, often these methods require complex surgical procedures and solely focus on motor function. Vagus nerve stimulation (VNS) is currently used in patients with epilepsy, depression, and migraine and is being investigated for its application in other disorders. In animal models of SCI, VNS significantly improved locomotor function by ameliorating inflammation and improving plasticity, suggesting its use in human subjects. SCI patients also suffer from nonmotor complications, including pain, gastrointestinal dysfunction, cardiovascular disorders, and chronic conditions such as obesity and diabetes. VNS has shown promising results in alleviating these conditions in non-SCI patients, which makes it a possible therapeutic option in SCI patients.