Behavioral Characterization of a Graded, Bilateral Cervical Spinal Cord Contusion Injury in Rats

Abstract

Spinal cord injury (SCI) is estimated to affect roughly 1.28 million individuals in the U.S. today and continually increases with 12,400 new incidences yearly. The effects of SCI result in varying complications that depend on impact magnitude and location along the spinal cord. Cervical SCI jeopardize fundamental functions for survival like respiratory capability and locomotive abilities including motor and sensory transmission and autonomic nervous system functions. A fifth of the cervical SCI population are mechanistically due to compression or contusion of the cord. Thus, a clinically-relevant and reproducible cervical contusion SCI model in experimental settings is important for the improved clinical translation of putative pharmacological therapeutic modalities. The Infinite Horizons (IH) Impactor (with a modified 4 mm probe) was used to create a cervical C5 SCI at graded severities, and an array of varying behavioral tests were utilized to assess overall rat fore- and hindlimb performance. The 200 kilodynes (kdyn) severity group would be the optimal force setting used on the IH Impactor in rat models because the force was strong enough to create moderately severe functional deficits without compromising basic functions of life.