Effects of durotomy versus myelotomy in the repair of spinal cord injury

Duraplasty promotes functional recovery by alleviating intraspinal pressure and edema following severe spinal cord compression injury in rabbits: Experimental studies

BACKGROUND

After acute traumatic spinal cord injury (tSCI), various surgical strategies have been developed to alleviate elevated intraspinal pressure (ISP) and secondary injury.

PURPOSE

Our study aimed to investigate the impacts of duraplasty and laminectomy on edema progression, perfusion and functional outcomes after severe balloon compression SCI.

STUDY DESIGN

In vivo animal study.

METHODS

Closed balloon compression injuries were induced at the T7 level in rabbits using an inflated volume of 50 μl. Laminectomy (1-level laminectomy: 1-laminectomy; 3-level laminectomy: 3-laminectomy) and duraplasty were performed immediately after model generation. ISP was monitored using a SOPHYSA probe at the epicenter within 7 days post-SCI. Edema progression, perfusion and damage severity were evaluated by serial multisequence MRI scans, behavioral and bladder scores within 8 weeks post-SCI. Blood-spinal cord barrier (BSCB) permeability and histopathology were subsequently analyzed.

RESULTS

After SCI, ISP was steeply elevated in the control and 1-laminectomy groups, peaking at 33.14±4.91 and 31.71±4.50 mmHg at 48 h post-SCI; whereas in the 3-laminectomy and duraplasty groups, ISP peaked at 29.43±4.04 and 12.14±1.86 mmHg (p<0.0001) at 72 h post-SCI. MRI and function scores showed that duraplasty significantly reduced the intramedullary lesion length (IMLL) and blood flow reduction ratio, and promoted fiber tract sparing and spinal cord functional recovery (p<0.01). Histopathology revealed that duraplasty significantly reduced BSCB permeability, tissue loss and inflammation and promoted axon preservation (p<0.01), while it did not increase early scar formation.

CONCLUSIONS

Duraplasty may alleviate secondary SCI and promote functional recovery. This neuroprotective mechanism may be related to reduced ISP and increased perfusion, resulting in reduced edema, BSCB permeability and inflammation and increased nerve fiber tract preservation.

CLINICAL SIGNIFICANCE

Duraplasty may promote functional recovery following severe tSCI patients, but further investigations are needed.

Hemorrhagic encephalopathies and myelopathies in dogs and cats: a focus on classification

The prevalence of hemorrhagic diseases of the central nervous system of dogs and cats is low compared to other diseases such as neoplasia and inflammation. However, the clinical consequences can be devastating. Several etiological and localization-based classification systems have been reported for intracerebral and spinal cord hemorrhage or hematomyelia in humans but similar systems do not exist in veterinary medicine. The authors propose an etiologic classification system for both intraparenchymal hemorrhagic encephalopathy and myelopathy following a review of the literature detailing the presentation, diagnosis, therapy, and prognosis of these diseases. A summary of the investigative and therapeutic approach to these cases is also provided.

Nerve Bypass Surgery for Spinal Cord Reconstruction

OBJECTIVE

Spinal cord injury (SCI) is a devastating condition that significantly decreases the patient's quality of life. Therefore, treatments that can facilitate nerve regeneration, reduce complications, and increase quality of life are valuable for these patients. In this study, we aimed to assess nerve bypass surgery's feasibility and clinical outcomes by transferring the intercostal nerves into the spinal cord.

METHODS

Eight patients with complete thoracic SCI and delayed presentation more than a year after the injury were analyzed retrospectively. All patients underwent nerve bypass surgery with the transfer of 2 pairs of intercostal nerves from proximal to the injury site to the anterolateral spinal cord, followed by duraplasty with fascia grafting to close the dura.

RESULTS

Six of the 8 (75%) patients demonstrated motor and sensory improvements, based on the American SCI Association score. Three patients demonstrated a limited recovery of motor function that could be independently triggered without ICN initiation. Five patients demonstrated evidence of cerebrospinal fluid leakage after surgery; however, only 1 patient complained of a headache.

CONCLUSIONS

Spinal cord bypass surgery is a potential reconstruction method to treat chronic complete thoracic SCI with functional improvements, and is worth further investigation.

Care needs of adults with spinal trauma in the prehospital and hospital setting from the perspective of patient care team: A qualitative research

BACKGROUND

Appropriate care of patients with definite spinal cord injury or at risk of it in the prehospital and hospital stages requires comprehensive planning in the health system. It is also the requirement of any successful program to explain the needs from the perspective of its stakeholders. Thus, this study aimed to discover the care needs of adults with spinal trauma in prehospital and hospital settings from the perspective of the patient care team.

MATERIALS AND METHODS

This qualitative study was conducted with the participation of urban and rural prehospital emergency personnel and emergency departments of educational and therapeutic hospitals affiliated to Isfahan, Tehran, Shiraz, Kermanshah, Ahvaz, and Yasuj Universities of Medical Sciences, through conducting 36 in-depth semi-structured interviews from September to December 2021. Using purposive sampling method, the participants were selected considering the maximum variation. The data saturation was reached after conducting interviews and group discussions with 36 subjects. Data were analyzed using conventional content analysis approach. Lundman and Graneheim approach were used for the study rigour. Data were simultaneously analyzed using MAXQDA software version 10.

RESULT

During the data analysis, two themes of prehospital care with two main categories (emergency care and management of secondary complications of spinal trauma) and hospital care with two main categories (emergency care and management of secondary complications of spinal trauma) emerged.

CONCLUSION

Emergency care and management of secondary complications of spinal cord injury in the prehospital and hospital stages can affect treatment results, improve quality of life, and reduce mortality rate, secondary injuries, and healthcare costs. Thus, identification of the care needs of the adults with spinal trauma from the perspective of the patient care team can help the authorities to plan appropriate interventions.

Randomized Controlled Trial of Durotomy as an Adjunct to Routine Decompressive Surgery for Dogs With Severe Acute Spinal Cord Injury

Although many interventions for acute spinal cord injury (SCI) appear promising in experimental models, translation directly from experimental animals to human patients is a large step that can be problematic. Acute SCI occurs frequently in companion dogs and may provide a model to ease translation. Recently, incision of the dura has been highlighted in both research animals and human patients as a means of reducing intraspinal pressure, with a view to improving perfusion of the injured tissue and enhancing functional recovery. Observational clinical data in humans and dogs support the notion that it may also improve functional outcome. Here, we report the results of a multi-center randomized controlled trial of durotomy as an adjunct to traditional decompressive surgery for treatment of severe thoracolumbar SCI caused by acute intervertebral disc herniation in dogs. Sample-size calculation was based on the proportion of dogs recovering ambulation improving from an expected 55% in the traditional surgery group to 70% in the durotomy group. Over a 3.5-year period, we enrolled 140 dogs, of which 128 had appropriate duration of follow-up. Overall, 65 (51%) dogs recovered ambulation. Recovery in the traditional decompression group was 35 of 62 (56%) dogs, and in the durotomy group 30 of 66 (45%) dogs, associated with an odds ratio of 0.643 (95% confidence interval: 0.320-1.292) and z-score of -1.24. This z-score indicates trial futility to reach the target 15% improvement over traditional surgery, and the trial was terminated at this stage. We conclude that durotomy is ineffective in improving functional outcome for severe acute thoracolumbar SCI in dogs. In the future, these data can be compared with similar data from clinical trials on duraplasty in human patients and will aid in determining the predictive validity of the "companion dog model" of acute SCI.

Schwann Cell-Derived Exosomes and Methylprednisolone Composite Patch for Spinal Cord Injury Repair

Spinal cord injury (SCI) can cause permanent loss of sensory and motor function, and there is no effective clinical treatment, to date. Due to the complex pathological process involved after injury, synergistic treatments are very urgently needed in clinical practice. We designed a nanofiber scaffold hyaluronic acid hydrogel patch to release both exosomes and methylprednisolone to the injured spinal cord in a non-invasive manner. This composite patch showed good biocompatibility in the stabilization of exosome morphology and toxicity to nerve cells. Meanwhile, the composite patch increased the proportion of M2-type macrophages and reduced neuronal apoptosis in an in vitro study. In vivo, the functional and electrophysiological performance of rats with SCI was significantly improved when the composite patch covered the surface of the hematoma. The composite patch inhibited the inflammatory response through macrophage polarization from M1 type to M2 type and increased the survival of neurons by inhibition neuronal of apoptosis after SCI. The therapeutic effects of this composite patch can be attributed to TLR4/NF-κB, MAPK, and Akt/mTOR pathways. Thus, the composite patch provides a medicine-exosomes dual-release system and may provide a non-invasive method for clinical treatment for individuals with SCI.

Pathophysiology and surgical decision-making in central cord syndrome and degenerative cervical myelopathy: correcting the somatotopic fallacy

Our understanding of Central Cord Syndrome (CCS), a form of incomplete spinal cord injury characterized by disproportionate upper extremity weakness, is evolving. Recent advances challenge the traditional somatotopic model of corticospinal tract organization within the spinal cord, suggesting that CCS is likely a diffuse injury rather than focal lesion. Diagnostic criteria for CCS lack consensus, and varied definitions impact patient identification and treatment. Evidence has mounted for early surgery for CCS, although significant variability persists in surgical timing preferences among practitioners. A demographic shift toward an aging population has increased the overlap between CCS and Degenerative Cervical Myelopathy (DCM). Understanding this intersection is crucial for comprehensive patient care. Assessment tools, including quantitative measures and objective evaluations, aid in distinguishing CCS from DCM. The treatment landscape for CCS in the context of pre-existing DCM is complex, requiring careful consideration of pre-existing neurologic injury, patient factors, and injury factors. This review synthesizes emerging evidence, outlines current guidelines in diagnosis and management, and emphasizes the need for ongoing research to refine our understanding and treatment strategies for this evolving patient population.

Case report: Traumatic hemorrhagic cervical myelopathy in a dog

A 1.5-year-old female entire French bulldog was referred for neurological evaluation, further diagnostic tests, and treatment 24 h after a road traffic accident. Initial emergency treatment, diagnostic tests, and stabilization had been performed by the referring veterinarian. Neurological examination revealed severe spastic non-ambulatory tetraparesis and was consistent with a C1-5 myelopathy. A magnetic resonance imaging (MRI) study revealed an irregular to elongated ovoid intramedullary lesion centered over the body of C2. The lesion showed marked signal heterogeneity with a central T2W and T2* hyperintense region, surrounded by a hypointense rim on both sequences. The lesion appeared heterogeneously T1W hypointense. The lesion was asymmetric (right-sided), affecting both white and gray matter. The C2-3 intervertebral disk appeared moderately degenerate with a Pfirrmann grade of 3. No evidence of vertebral fracture or luxation was found on radiographs or MRI of the vertebral column. Additional soft tissue abnormalities in the area of the right brachial plexus were suggestive of brachial plexus and muscle injury. A diagnosis of traumatic hemorrhagic myelopathy at the level of C2 and concurrent brachial plexus injury was formed. Conservative treatment was elected and consisted of physiotherapy, bladder care with an indwelling urinary catheter, repeated IV methadone based on pain scoring (0.2 mg/kg), oral meloxicam 0.1 mg/kg q24h, and oral gabapentin 10 mg/kg q8h. The dog was discharged after 4 days, with an indwelling urinary catheter and oral medication as described. The catheter was replaced two times by the referring veterinarian and finally removed after 10 days. Thereafter, voluntary urination was seen. During the 2 months after the road traffic accident, slow recovery of motor function was seen. The right thoracic limb recovery progressed more slowly than the left limb, also showing some lower motor neuron signs during follow-up. This was judged to be consistent with a right-sided brachial plexus injury. The dog was reported ambulatory with mild residual ataxia and residual monoparesis of the right thoracic limb at the last follow-up 3 months post-injury. This case report highlights the MRI-based diagnosis of traumatic hemorrhagic myelopathy in a dog. A fair short-term outcome was achieved with conservative treatment in this case.

Impact of Serum Cystatin C Level on Long-Term Cognitive Impairment After Acute Ischemic Stroke and Transient Ischemic Attack

Objective

Cognitive impairment after stroke/transient ischemic attack (TIA) has a high prevalence. Cystatin C (CysC) has been found as a novel biomarker of neurodegenerative diseases, such as dementia and Alzheimer's disease. We aimed to explore the possible correlations of serum CysC level with cognitive impairment in patients who had mild ischemic stroke and TIA after 1 year.

Methods

We measured serum CysC level in 1025 participants with a minor ischemic stroke/TIA from enrolled from the Impairment of Cognition and Sleep (ICONS) study of the China National Stroke Registry-3 (CNSR-3). They were divided into four groups according to quartiles of baseline CysC levels. Patients' cognitive functions were assessed by Montreal Cognitive Assessment (MoCA)-Beijing at day 14 and at 1 year. Multiple logistic regression models were performed to evaluate the relationship between CysC and post-stroke cognitive impairment (PSCI) at 1-year follow-up.

Results

Cognitive impairment was defined as MoCA-Beijing ≤22. Most patients were in 60s (61.52±10.97 years old) with a median (interquartile range) National Institute of Health Stroke Scale(NIHSS) score of 3.00 (4.00) and greater than primary school level of education, and 743 participants (72.49%) were male. Among the 1025 participants, 331 participants (32.29%) patients suffered PSCI at 1-year follow-up. A U-shaped association was observed between CysC and 1-year PSCI [quartile (Q)1 vs Q3: adjusted odds ratio (aOR) 2.69, 95% CI 1.67-4.34, p < 0.0001; Q2 vs Q3: aOR 1.63, 95% CI 1.03-2.57, p = 0.0354; Q4 vs Q3: aOR 1.83, 95% CI 1.16-2.87, p = 0.009]. Moreover, the U-shaped trends were also found between CysC level and the subscores of attention, recall, abstraction and language in MoCA.

Conclusion

CysC showed a U-shaped correlation with 1-year overall cognitive function. It is probable that measurement of the serum CysC level would aid in the early diagnosis of PSCI.

Spinal cord injury: molecular mechanisms and therapeutic interventions

Spinal cord injury (SCI) remains a severe condition with an extremely high disability rate. The challenges of SCI repair include its complex pathological mechanisms and the difficulties of neural regeneration in the central nervous system. In the past few decades, researchers have attempted to completely elucidate the pathological mechanism of SCI and identify effective strategies to promote axon regeneration and neural circuit remodeling, but the results have not been ideal. Recently, new pathological mechanisms of SCI, especially the interactions between immune and neural cell responses, have been revealed by single-cell sequencing and spatial transcriptome analysis. With the development of bioactive materials and stem cells, more attention has been focused on forming intermediate neural networks to promote neural regeneration and neural circuit reconstruction than on promoting axonal regeneration in the corticospinal tract. Furthermore, technologies to control physical parameters such as electricity, magnetism and ultrasound have been constantly innovated and applied in neural cell fate regulation. Among these advanced novel strategies and technologies, stem cell therapy, biomaterial transplantation, and electromagnetic stimulation have entered into the stage of clinical trials, and some of them have already been applied in clinical treatment. In this review, we outline the overall epidemiology and pathophysiology of SCI, expound on the latest research progress related to neural regeneration and circuit reconstruction in detail, and propose future directions for SCI repair and clinical applications.

Significance of spinal cord perfusion pressure following spinal cord injury: A systematic scoping review

This scoping review systematically reviewed relevant research to summarize the literature addressing the significance of monitoring spinal cord perfusion pressure (SCPP) in acute traumatic spinal cord injury (SCI). The objectives of the review were to (1) examine the nature of research in the field of SCPP monitoring in SCI, (2) summarize the key research findings in the field, and (3) identify research gaps in the existing literature and future research priorities. Primary literature searches were conducted using databases (Medline and Embase) and expanded searches were conducted by reviewing the references of eligible articles and searches of Scopus, Web of Science core collection, Google Scholar, and conference abstracts. Relevant data were extracted from the studies and synthesis of findings was guided by the identification of patterns across studies to identify key themes and research gaps within the literature. Following primary and expanded searches, a total of 883 articles were screened. Seventy-three articles met the review inclusion criteria, including 34 original research articles. Other articles were categorized as conference abstracts, literature reviews, systematic reviews, letters to the editor, perspective articles, and editorials. Key themes relevant to the research question that emerged from the review included the relationship between SCPP and neurological recovery, the safety of monitoring pressures within the intrathecal space, and methods of intervention to enhance SCPP in the setting of acute traumatic SCI. Original research that aims to enhance SCPP by targeting increases in mean arterial pressure or reducing pressure in the intrathecal space is reviewed. Further discussion regarding where pressure within the intrathecal space should be measured is provided. Finally, we highlight research gaps in the literature such as determining the feasibility of invasive monitoring at smaller centers, the need for a better understanding of cerebrospinal fluid physiology following SCI, and novel pharmacological interventions to enhance SCPP in the setting of acute traumatic SCI. Ultimately, despite a growing body of literature on the significance of SCPP monitoring following SCI, there are still a number of important knowledge gaps that will require further investigation.

A comparative analysis of differentially expressed genes in rostral and caudal regions after spinal cord injury in rats

The initial mechanical damage of a spinal cord injury (SCI) triggers a progressive secondary injury cascade, which is a complicated process integrating multiple systems and cells. It is crucial to explore the molecular and biological process alterations that occur after SCI for therapy development. The differences between the rostral and caudal regions around an SCI lesion have received little attention. Here, we analyzed the differentially expressed genes between rostral and caudal sites after injury to determine the biological processes in these two segments after SCI. We identified a set of differentially expressed genes, including Col3a1, Col1a1, Dcn, Fn1, Kcnk3, and Nrg1, between rostral and caudal regions at different time points following SCI. Functional enrichment analysis indicated that these genes were involved in response to mechanical stimulus, blood vessel development, and brain development. We then chose Col3a1, Col1a1, Dcn, Fn1, Kcnk3, and Nrg1 for quantitative real-time PCR and Fn1 for immunostaining validation. Our results indicate alterations in different biological events enriched in the rostral and caudal lesion areas, providing new insights into the pathology of SCI.

Elevated intraspinal pressure in traumatic spinal cord injury is a promising therapeutic target

The currently recommended management for acute traumatic spinal cord injury aims to reduce the incidence of secondary injury and promote functional recovery. Elevated intraspinal pressure (ISP) likely plays an important role in the processes involved in secondary spinal cord injury, and should not be overlooked. However, the factors and detailed time course contributing to elevated ISP and its impact on pathophysiology after traumatic spinal cord injury have not been reviewed in the literature. Here, we review the etiology and progression of elevated ISP, as well as potential therapeutic measures that target elevated ISP. Elevated ISP is a time-dependent process that is mainly caused by hemorrhage, edema, and blood-spinal cord barrier destruction and peaks at 3 days after traumatic spinal cord injury. Duraplasty and hypertonic saline may be promising treatments for reducing ISP within this time window. Other potential treatments such as decompression, spinal cord incision, hemostasis, and methylprednisolone treatment require further validation.

Detection and Analysis of Perfusion Pressure through Measuring Oxygen Saturation and Requirement of Dural Incision Decompression after Laminectomy

BACKGROUND

Traumatic spinal cord injury (SCI) can continue and transform long after the time of initial injury. Preventing secondary injury after SCI is one of the most significant challenges, and early intervention to return the blood flow at the injury site can minimize the likelihood of secondary injury.

OBJECTIVE

The purpose of this study is to investigate whether laminectomy can achieve the spinal cord blood flow by measuring the spinal blood oxygen saturation intraoperatively without the presence of light.

METHODS

Between June and August 2021, eight patients were admitted after traumatic spinal cord injury for surgical treatment. We explored the effectiveness of laminectomy and whether the patients required further procedures or not. We used a brain oxygen saturation monitor at the spine injury site under dark conditions.

RESULTS

Eight cervical trauma patients, six males and two females, underwent laminectomy decompression. Three patients' ASIA grade improved by one level, and one patient showed slight motor-sensory improvement. Oxygen saturation was in the normal range.

CONCLUSION

Performing bony decompression can show good results. Therefore, finding an examination method to confirm the improvement of blood perfusion by measuring oxygen saturation at the injury site after laminectomy is essential to avoid other complications.

Effect of combination therapy with neural stem cell transplantation and teramethylpyrazine in rats following acute spinal cord injury

OBJECTIVES

This study was to explore the effects of teramethylpyrazine (TMP) administered in conjunction with neural stem cell transplantation on motor function, pathological lesions and the Janus kinase (JAK)2/signal transducer and activator of transcription 3 signal transduction pathway in rats following acute spinal cord injury (SCI).

METHODS

Female Sprague-Dawley rats were randomly divided into sham, model, neural stem cells (NSCs) and NSCs+TMP groups. Motor function was evaluated using the Basso, Beattie, Bresnahan scale. Spinal cord neuropathies and neuron apoptosis were observed by HE and TUNEL staining. The brain-derived neurotrophic factor (BDNF), Nogo-A, JAK2 and p-JAK2 protein levels were measured by western blot analysis.

RESULTS

NSCs+TMP significantly improved rat motor function, attenuated impaired spinal cords, and decreased cellular apoptosis, compared with NSCs therapy alone (P < 0.05). In addition, expression of BDNF protein was significantly higher in NSCs+TMP rats compared with other groups regardless of time postinjury (P < 0.05). The highest expression levels of Nogo-A protein were observed in the model group. The expression of p-JAK2 in the NSCs+TMP group was relatively lower than the model and NSCs groups (P < 0.05).

CONCLUSIONS

In rats with SCI, NSCs+TMP effectively improved motor function and offered spinal cord protection by increasing BDNF and decreasing Nogo-A levels, as well as inhibiting the JAK2/STAT3 signal transduction pathway, suggesting that TMP could be a useful agent in NSCs transplantation in the treatment of SCI.

Surfer Myelopathy in Children: A Case Series Study

OBJECTIVE

The cause of surfer myelopathy remains enigmatic and long-term follow-up outcomes are not well documented. In the present study, the mechanisms underlying surfer myelopathy in children are analyzed and the long-term follow-up outcomes are reported.

METHODS

Clinical data from 3 institutions were retrospectively analyzed. Patients were assessed using the American Spinal Injury Association Impairment Scale (AIS) on admission and at follow-up. The mechanisms were studied by analyzing patients' medical history, magnetic resonance imaging, and magnetic resonance angiography. The prognosis of long-term follow-up was summarized.

RESULTS

Thirty-one children were diagnosed with surfer myelopathy. Intramedullary high-intensity T2 signal from mid to lower thoracic level to conus was found during the acute stage. Follow-up magnetic resonance imaging in the subacute stage showed cranial progression of the T2 hyperintensity up to 1-10 vertebral segments, and no neurologic deterioration was found. Intramedullary lesion length between the complete and incomplete injury was significantly different (P < 0.01) in the subacute phase. Flow voids around nerve roots and in the epidural space were detected in 18 patients and 15 patients, respectively, on axial T2-weighted imaging. Enlarged tortuous veins were found in 3 of 6 patients who underwent spinal magnetic resonance angiography, which were discontinuous around nerve root. During long-term follow-up, no patients with AIS grade A recovered, and atrophic cord was observed in the later stage in 14 patients. Patients with incomplete injury had different recoveries.

CONCLUSIONS

Surfer myelopathy in children is caused by spinal venous hypertension. The AIS grade on admission is a predictor of prognosis.

High mobility group box 1 mediates inflammatory response of astrocytes via cyclooxygenase 2/prostaglandin E2 signaling following spinal cord injury

High mobility group box 1 (HMGB1) interacts with pattern-recognition receptors of immune cells to activate the inflammatory response. Astrocytes play a positive role in the inflammatory response of the central nervous system by expressing a broad range of pattern-recognition receptors. However, the underlying relationship between HMGB1 and the inflammatory reaction of astrocytes remains unclear. In this study, we established rat models of spinal cord injury via laminectomy at the T8–10 level, and the injured spinal cord was subjected to transcriptome sequencing. Our results showed that the HMGB1/Toll-like receptor 4 (TLR4) axis was involved in the activation of astrocyte inflammatory response through regulation of cyclooxygenase 2 (COX2)/prostaglandin E2 (PGE2) signaling. Both TLR4 and COX2 were distributed in astrocytes and showed elevated protein levels following spinal cord injury. Stimulation of primary astrocytes with recombinant HMGB1 showed that COX2 and microsomal PGE synthase (mPGES)-1, rather than COX1, mPGES-2, or cytosolic PGE synthase, were significantly upregulated. Accordingly, PGE2 production in astrocytes was remarkably increased in response to recombinant HMGB1 challenges. Pharmacologic blockade of TLR2/4 attenuated HMGB1-mediated activation of the COX2/PGE2 pathway. Interestingly, HMGB1 did not impact the production of tumor necrosis factor-α or interleukin-1β in astrocytes. Our results suggest that HMGB1 mediates the astrocyte inflammatory response through regulating the COX2/PGE2 signaling pathway. The study was approved by the Laboratory Animal Ethics Committee of Nantong University, China (approval No. 20181204-001) on December 4, 2018.

Clinical guidelines for neurorestorative therapies in spinal cord injury (2021 China version)

Treatment of spinal cord injury (SCI) remains challenging. Considering the rapid developments in neurorestorative therapies for SCI, we have revised and updated the Clinical Therapeutic Guidelines for Neurorestoration in Spinal Cord Injury (2016 Chinese version) of the Chinese Association of Neurorestoratology (Preparatory) and China Committee of International Association of Neurorestoratology. Treatment of SCI is a systematic multimodal process that aims to improve survival and restore neurological function. These guidelines cover real-world comprehensive neurorestorative management of acute, subacute, and chronic SCI and include assessment and diagnosis, pre-hospital first aid, treatment, rehabilitation, and complication management.

Exogenous platelet-derived growth factor improves neurovascular unit recovery after spinal cord injury

The blood-spinal cord barrier plays a vital role in recovery after spinal cord injury. The neurovascular unit concept emphasizes the relationship between nerves and vessels in the brain, while the effect of the blood-spinal cord barrier on the neurovascular unit is rarely reported in spinal cord injury studies. Mouse models of spinal cord injury were established by heavy object impact and then immediately injected with platelet-derived growth factor (80 μg/kg) at the injury site. Our results showed that after platelet-derived growth factor administration, spinal cord injury, neuronal apoptosis, and blood-spinal cord barrier permeability were reduced, excessive astrocyte proliferation and the autophagy-related apoptosis signaling pathway were inhibited, collagen synthesis was increased, and mouse locomotor function was improved. In vitro, human umbilical vein endothelial cells were established by exposure to 200 μM H₂O₂. At 2 hours prior to injury, in vitro cell models were treated with 5 ng/mL platelet-derived growth factor. Our results showed that expression of blood-spinal cord barrier-related proteins, including Occludin, Claudin 5, and β-catenin, was significantly decreased and autophagy was significantly reduced. Additionally, the protective effects of platelet-derived growth factor could be reversed by intraperitoneal injection of 80 mg/kg chloroquine, an autophagy inhibitor, for 3 successive days prior to spinal cord injury. Our findings suggest that platelet-derived growth factor can promote endothelial cell repair by regulating autophagy, improve the function of the blood-spinal cord barrier, and promote the recovery of locomotor function post-spinal cord injury. Approval for animal experiments was obtained from the Animal Ethics Committee, Wenzhou Medical University, China (approval No. wydw2018-0043) in July 2018.

A sandwich structured drug delivery composite membrane for improved recovery after spinal cord injury under longtime controlled release

A sandwich structured composite membrane for longtime controlled release of nerve growth factor (NGF) to repair spinal cord injury (SCI) is prepared through electrospray. In this system, PLA film is used as the sealing layer to prevent drug diffusion and provide mechanical support, PLGA microspheres as the sandwich layer to load and controlled release NGF, and chitosan (CS) film as the planting layer to seed bone marrow mesenchymal stem cells (BMSCs). The composite membrane has good biocompatibility and can effectively promote PC-12 cells to differentiate into neurons. In addition, the composite membrane can be directly applied to the injured areas without further damage. The longtime sustained release of NGF guaranteed enough requirement time for SCI repair, which will decrease the administration frequency and improve patient compliance. The administration of BMSCs coupled with the sandwich composite membrane effectively relieves SCI, decreases cavity formation, enhances neuronal regeneration and tissue repair, as well as improves the recovery of locomotor functions. Overall, this present work provides a future perspective for the treatment of SCI by the NGF-loaded sandwich composite membrane with prolonged drug release function.

Emerging and Adjunctive Therapies for Spinal Cord Injury Following Acute Canine Intervertebral Disc Herniation

Some dogs do not make a full recovery following medical or surgical management of acute canine intervertebral disc herniation (IVDH), highlighting the limits of currently available treatment options. The multitude of difficulties in treating severe spinal cord injury are well-recognized, and they have spurred intense laboratory research, resulting in a broad range of strategies that might have value in treating spinal cord-injured dogs. These include interventions that aim to directly repair the spinal cord lesion, promote axonal sparing or regeneration, mitigate secondary injury through neuroprotective mechanisms, or facilitate functional compensation. Despite initial promise in experimental models, many of these techniques have failed or shown mild efficacy in clinical trials in humans and dogs, although high quality evidence is lacking for many of these interventions. However, the continued introduction of new options to the veterinary clinic remains important for expanding our understanding of the mechanisms of injury and repair and for development of novel and combined strategies for severely affected dogs. This review outlines adjunctive or emerging therapies that have been proposed as treatment options for dogs with acute IVDH, including discussion of local or lesion-based approaches as well as systemically applied treatments in both acute and subacute-to-chronic settings. These interventions include low-level laser therapy, electromagnetic fields or oscillating electrical fields, adjunctive surgical techniques (myelotomy or durotomy), systemically or locally-applied hypothermia, neuroprotective chemicals, physical rehabilitation, hyperbaric oxygen therapy, electroacupuncture, electrical stimulation of the spinal cord or specific peripheral nerves, nerve grafting strategies, 4-aminopyridine, chondroitinase ABC, and cell transplantation.

Guideline for diagnosis and treatment of spine trauma in the epidemic of COVID-19

Outbreak of COVID-19 is ongoing all over the world. Spine trauma is one of the most common types of trauma and will probably be encountered during the fight against COVID-19 and resumption of work and production. Patients with unstable spine fractures or continuous deterioration of neurological function require emergency surgery. The COVID-19 epidemic has brought tremendous challenges to the diagnosis and treatment of such patients. To coordinate the diagnosis and treatment of infectious disease prevention and spine trauma so as to formulate a rigorous diagnosis and treatment plan and to reduce the disability and mortality of the disease, multidisciplinary collaboration is needed. This expert consensus is formulated in order to (1) prevent and control the epidemic, (2) diagnose and treat patients with spine trauma reasonably, and (3) reduce the risk of cross-infection between patients and medical personnel during the treatment.