The effect of timing of decompression following traumatic spinal cord injury (SCI) remains unclear, as clinical and preclinical studies have demonstrated varying results. There remains a question of whether certain sub-groups of SCI could see greater benefits than others from early decompression. Dislocation is the most commonly seen injury mechanism but has never been investigated with respect to residual compression in an animal model.

The goal of this thesis was add residual compression to an existing rat cervical dislocation model and to examine the effect of time of residual compression and velocity of injury with this model.

Dislocation injuries were conducted on forty-six male, Sprague-Dawley rats in four groups:​ two timings of decompression (24 minutes, 240 minutes) and two velocities (10mm/s, 500mm/s). All injuries involved dislocation between the C5/C6 vertebrae in an anterior-posterior direction to 1.45mm and residual compression of 0.8mm. Animals were evaluated for motor function using the Martinez open field, grip strength, and grooming tests for 6 weeks post-injury.

High velocities consistently produced more severe injuries than low velocity. Correlation coefficients between 0.46 and 0.58 (p<0.05) were seen between velocity and injury severity. Longer time of residual compression did not produce more severe injuries and no significant correlations were seen between timing of residual compression and injury severity.

These findings demonstrate that velocity is a more important factor than timing of residual compression in determining injury severity in a dislocation model of SCI.