Virginia Research Day 2025

Medical Student Research Biomedical

14 Behavior Response of Acute Mild Spinal Cord Injury

Anastasiya Loos 1 ; Taylor Dickson 1 ; Carly Norris 2 ; Susan Murphy 2,3 ; Pamela VandeVord 2,3,4 ; Ramu, Kelly C.S. Roballo 1,5 ; Kelly Roballo, DVM, PhD Corresponding author: aloos@vt.vcom.edu

1 Edward Via College of Osteopathic Medicine- Virginia Campus 2 School of Biomedical Engineering and Sciences, Virginia Tech 3 Department of Biomedical Engineering and Mechanics, Virginia Tech 4 Veterans Affairs Medical Center, Salem, VA 5 Department of Biomedical Sciences and Pathobiology, Virginia Maryland College of Veterinary Medicine

Spinal cord injury (SCI) is a pertinent problem that affects approximately 18,000 new individuals annually in the U.S.A. Recently, our group partnered with Dr. VandeVord to help in the development of a new preclinical model that could mimic mild traumatic SCIs. Traumatic injuries to the spinal cord, much like those seen in traumatic brain injuries (TBI), lead to several phases of tissue damage over time. Inflammatory processes initiated by trauma lead to irreversible tissue damage, irreversible loss of function, and pain by 72 hours post-injury; thus, a critical time for intervention is the period immediately following SCI. Using this preclinical thoracolumbar SCI model, this study attempted to delineate the behavior response due to pain in the spinal cord in a rat model. For that, animals were divided into

sham and SCI groups with 8 animals per group, and animals’ baseline behavior was recorded. Next, the SCI group received a blast-wave type of injury to mimic mild SCI due to trauma. Sham groups were exposed to only the noise of the blast. Animals were then followed up to 3 days post-injury. Behavior tests were performed at baseline, 48hrs, and/or 72hrs post injury. The behavioral tests after SCI were divided to address spinal reflexive pain and non-spinal reflexive pain. For spinal non-reflexive pain, we performed the Open Field Test (OFT) and the Basso-Beattie Bresnahan (BBB). For spinal reflexive pain, we performed the mechanical hyperalgesia test (Von Frey). The OFT test accessed the non-nociceptive pain symptoms and avoidance of pain-inducing activity. We measured the total distance traveled,

mean velocity, time stationary, and the number of rearings in the five-minute testing session. The BBB was used to evaluate proprioception, coordination, and level of injury. Then Von Frey used filaments to evoke pain and it was used to access allodynia by the withdrawal response. All procedures performed in this project received IACUC approval (#22-182). As a result of the pain assessment based on the behavior of the injured animals, we observed hyperalgesia and anxiety-like behavior with a decrease in proprioception and coordination. This study showed how acute pain isn’t only a biological response, but also a social and emotional response that leads to singular behaviors.

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