Use of a Porcine Model for Studying Spinal Cord Injury

At this year’s Society for Neuroscience (SfN) meeting, our team presented a poster highlighting the advantages of using a porcine model to bridge the translational gap often encountered with traditional rodent studies. The work underscores the anatomical and physiological similarities that make pigs a more suitable large-animal option for evaluating therapeutic strategies.

Download full poster here.

Introduction

Rodent models for spinal cord injury (SCI) are well documented for early studies of regenerative abilities of implants and treatments for SCI. However, there are limitations to the ability to translate the information to humans. Anatomically and physiologically, the spinal cord of rats is significantly different from humans:

• The rat corticospinal tract is primarily dorsal
• Distinct tract organization differs from humans
• Significant differences in spinal cord diameter
• Distance between the cell bodies of injured axons and the injury site
• Relative dedication of the cord to specific ascending and descending pathways
• Degree of vascularization, size of the sensory and motor neuron populations, and white/gray matter composition
• Different metabolic rates, immune responses, and regenerative capacity that may not translate to human outcomes (i.e., rats heal substantially faster than humans)

However, a porcine SCI model is more adequate for the following reasons:

• Anatomical similarity: Porcine spinal cord anatomy, including white matter distribution and tract organization, more closely resembles human anatomy compared to canine models
• Physiological relevance: Similar cardiovascular and respiratory responses to SCI, making them better models for studying secondary injury mechanisms and therapeutic interventions
• Ethical considerations: Fewer ethical concerns and regulatory hurdles associated with using pigs compared to dogs in research settings
• Standardization: Pig models offer better standardization opportunities due to more controlled breeding and genetic backgrounds

Conclusions

This study introduces a porcine spinal cord injury model that integrates conventional outcome metrics, including body weight and motor function scores, with translational endpoints such as electrophysiological assessments and automated gait analysis.

The experimental findings indicate that the magnitude of the dropped weight influences injury severity. The data show that a 15 cm drop height was associated with more pronounced neurological deficits when compared to a 10 cm drop.

Analogous to clinical scenarios in humans, early post- injury electrophysiological measurements reliably forecast functional outcomes, facilitating effective stratification and group allocation of experimental animals for therapeutic interventions, which is crucial for minimizing experimental variability.