Reproducibility - The key towards clinical implementation of spinal cord injury treatments?

Traumatic spinal cord and spinal column injuries: A bibliometric analysis of the 200 most cited articles

Study Design

Bibliometric analysis.

Objectives

This study aimed to highlight the 200 most influential articles related to traumatic spinal cord and spinal column injuries and provide an insight of past and current global trends in spinal trauma research.

Methods

The Web of Science database was used to identify the top 200 most cited articles on the topic of traumatic spinal cord injury (SCI) and spinal column injuries between using a prespecified algorithm. The articles were manually reviewed; bibliometrics were collected on title, first and corresponding authors' country, institution, journal, publication year, and citation data.

Results

The search string yielded 30,551 articles during 1977-2019. The average time from the publication was 19.5 years. A total of 1356 authors contributed to 67 different journals, the top 200 most cited articles amassing a total of 88,115 citations and an average 440.6 citations. The United States of America (USA) contributed the most with 110 articles; the top institution was the University of Toronto with 34 publications. Most studies focused on basic science research on SCI. Keyword analysis revealed the most commonly used keywords: SCI, inflammation, apoptosis, incidence/prevalence, and regeneration; four word-clusters were identified. Institutions from the USA and Canada collaborated the most and two major and two minor institutional collaboration subnetworks were identified. Co-citation analysis detected three main clusters of authors.

Conclusion

This overview of the most cited articles on traumatic spinal cord and spinal column injuries provides insight into the international spinal trauma community and the terrain in this field, potentially acting as a springboard for further collaboration development.

Recent progress and challenges in the treatment of spinal cord injury

Spinal cord injury (SCI) disrupts the structural and functional connectivity between the higher center and the spinal cord, resulting in severe motor, sensory, and autonomic dysfunction with a variety of complications. The pathophysiology of SCI is complicated and multifaceted, and thus individual treatments acting on a specific aspect or process are inadequate to elicit neuronal regeneration and functional recovery after SCI. Combinatory strategies targeting multiple aspects of SCI pathology have achieved greater beneficial effects than individual therapy alone. Although many problems and challenges remain, the encouraging outcomes that have been achieved in preclinical models offer a promising foothold for the development of novel clinical strategies to treat SCI. In this review, we characterize the mechanisms underlying axon regeneration of adult neurons and summarize recent advances in facilitating functional recovery following SCI at both the acute and chronic stages. In addition, we analyze the current status, remaining problems, and realistic challenges towards clinical translation. Finally, we consider the future of SCI treatment and provide insights into how to narrow the translational gap that currently exists between preclinical studies and clinical practice. Going forward, clinical trials should emphasize multidisciplinary conversation and cooperation to identify optimal combinatorial approaches to maximize therapeutic benefit in humans with SCI.

Therapeutic repair for spinal cord injury: combinatory approaches to address a multifaceted problem

The recent years saw the advent of promising preclinical strategies that combat the devastating effects of a spinal cord injury (SCI) that are progressing towards clinical trials. However, individually, these treatments produce only modest levels of recovery in animal models of SCI that could hamper their implementation into therapeutic strategies in spinal cord injured humans. Combinational strategies have demonstrated greater beneficial outcomes than their individual components alone by addressing multiple aspects of SCI pathology. Clinical trial designs in the future will eventually also need to align with this notion. The scenario will become increasingly complex as this happens and conversations between basic researchers and clinicians are required to ensure accurate study designs and functional readouts.

Assessing Rat Forelimb and Hindlimb Motor Unit Connectivity as Objective and Robust Biomarkers of Spinal Motor Neuron Function

Sensitive and objective biomarkers of neuronal injury, degeneration, and regeneration can help facilitate translation of experimental findings into clinical testing. Whereas measures of upper motor neuron connectivity have been readily established, functional assessments of lower motor neuron (LMN) innervation of forelimb muscles are lacking. Compound muscle action potential (CMAP) and motor unit (MU) number estimation (MUNE) are well-established methods that allow longitudinal MU integrity monitoring in patients. In analogy we refined CMAP and MUNE methods for assessing spinal MU input in the rat forelimb and hindlimb. Repeated CMAP and MUNE recordings are robust (coefficients of variability: 4.5-11.3%), and MUNE measurements from forelimb wrist flexor muscles (415 ± 8 [SEM]) align with back-traced anatomical LMN counts (336 ± 16 [SEM]). For disease validation, cross-sectional blinded electrophysiological and muscle contractility measurements were obtained in a cohort of G93A SOD1 mutant overexpressing rats and compared with controls. Longitudinal assessment of mutant animals demonstrated progressive motor unit decline in the hindlimb to a greater extent than the forelimb. Hindlimb CMAP and MUNE demonstrated strong correlations with plantarflexion muscle contractility. Cross-species assessment of upper/fore- limb and lower/hind- limb motor units using objective electrophysiological CMAP and MUNE values as biomarkers will guide and improve bi-directional translation.