Naturally Occurring Disk Herniation in Dogs: An Opportunity for Pre-Clinical Spinal Cord Injury Research

Abstract

Traumatic spinal cord injuries represent a significant source of morbidity in humans. Despite decades of research using experimental models of spinal cord injury to identify candidate therapeutics, there has been only limited progress toward translating beneficial findings to human spinal cord injury. Thoracolumbar intervertebral disk herniation is a naturally occurring disease that affects dogs and results in compressive/contusive spinal cord injury. Here we discuss aspects of this disease that are analogous to human spinal cord injury, including injury mechanisms, pathology, and metrics for determining outcomes. We address both the strengths and weaknesses of conducting pre-clinical research in these dogs, and include a review of studies that have utilized these animals to assess efficacy of candidate therapeutics. Finally, we consider a two-species approach to pre-clinical data acquisition, beginning with a reproducible model of spinal cord injury in the rodent as a tool for discovery with validation in pet dogs with intervertebral disk herniation.

The importance of the quadruped animal model in functional neurorehabilitation in the human biped

“…Likewise, in animals with incomplete spinal cord injuries PICs are still produced, however, their amplifying effect is not achieved and therefore muscle activation does not occur (Heckman, 2014;Levine et al, 2011;Musienko et al, 2012).…”

“…The primary lesion in both species occurs under the form of compression/contusion to the ventral area of the spinal cord (Levine et al, 2011).…”

Surgical treatment of spinal cord compression in client owned dogs with different grades of neurological dysfunction

“…Despite decades of research to identify the new therapeutics, there has been only limited progress toward the beneficial findings. Thoracolumbar intervertebral disk herniation is the most common naturally occurring spinal disease in dogs and results in compressive and contusive SCI [2,7,10]. The most common treatment for SCI is early stabilization of the spinal column followed by surgical decompression and stabilization and minimizing secondary changes [6].…”

Development of a neuromusculoskeletal computer model in a chondrodystrophic dog.

“…An estimated 2% of dogs develop IVDD during their lifetimes (Bergknut et al, 2012), but the risk is substantially higher -between 19 and 24% -for chondrodystrophic breeds (notably Dachshunds) (Levine, J. M. et al, 2011).…”

“…External forces are generally limited to ground reaction forces in healthy subjects, which can be measured using a standard force plate. However, dogs with severe IVDH are often incapable of supporting their own body weight post injury, as well as postsurgery (Levine, Levine et al 2011). Body weight support (BWS) has been provided by holding the base of the tail (Olby, Harris et al 2004) or using a support band situated around the abdomen (Hamilton, Franklin et al 2007), neither of which quantify the applied force.…”