Assessing gait impairment following experimental traumatic brain injury in mice

Although gait disturbance is frequently documented among patients with traumatic brain injury (TBI), gait data from animal models of TBI are lacking. To determine the effect of TBI on gait function in adult mice, we assessed gait changes following unilateral controlled cortical impact (CCI) using a computer-assisted automated gait analysis system. Three days after CCI, intensity, area or width of paw contact were significantly decreased in forepaw(s) while the relative paw placement between the fore and hindpaws altered, suggesting that TBI affected sensorimotor status and reduced inter-limb coordination. Similar to TBI patients, CCI decreased gait velocity and stride length, and prolonged stance and swing phase in mice. Following CCI, step pattern was also changed with increasing use in the ipsilateral-diagonal limb sequence. Our results indicate that gait analysis provides great insight into both spatial and temporal aspects of limb function changes during overground locomotion in quadruped species with head injury that are valuable for the purpose of treatment and rehabilitation. Our study also provides additional functional validation for the established mouse CCI model that is relevant to human head injury.