Establishing Indicative Neurofilament Gradients Based on Severity of Spinal Cord Injury.

INTRODUCTION

Acute traumatic spinal cord injury (SCI) results in a lifelong condition without any standardized biomarker or corresponding interventions. The objective of this study was to correlate changes in fluid biomarkers with the severity of SCI.

METHODS

The test model used forces of 100 and 200 kdyn. Both of these severities have been established for acute SCI models. Motor evoked potentials (MEPs) and somatosensory evoked potentials (SSEPs) and Basso, Beattie, and Bresnahan (BBB) scores were recorded at both levels of force at various timepoints from before injury to up to 72 hours after SCI. Serum levels for neurofilament heavy chain (NfH) and light chain (NfL) biomarker concentrations were collected at the same timepoints as well.

RESULTS

An expected decrease in the amplitude of MEPs and SSEPs was observed following impact, with signals from the 200 kdyn group exhibiting a greater decline. Likewise, BBB scores showing locomotion also decreased post-SCI. Concentrations of the neurofilaments greatly increased post-SCI. In the 100 kdyn group, a statistically significant negative correlation was found between the BBB score and NfH concentration. In the 200 kdyn injury group, a negative trend was found between the neurofilaments and BBB scores.

CONCLUSIONS

A negative correlation was observed between biomarkers and functional outcome scores with statistical significance for the 100 kdyn injury. As such, this study demonstrates the potential usefulness of these biomarkers in SCI, especially with regard to impact severity. Futures studies may be conducted at various impact forces to establish a biomarker gradient based on severity of injury.