The CatWalk XT® is a valid tool for objective assessment of motor function in the acute phase after controlled cortical impact in mice

Abstract

Background: Despite multiple experimental models of traumatic brain injury (TBI) being available, objective assessment of gait and motor function in rodents remains difficult; therefore, we studied the value of the CatWalk XT® gait analysis as an observer independent, automated method for outcome assessment in one of the most frequently used preclinical TBI model, the controlled cortical impact (CCI), in mice.

Methods: C57Bl/6 mice were subjected to either right parietal CCI or a sham procedure. Functional outcome was assessed using the CatWalk XT® (Version 10.6) as well as the hole board test at days one, three and seven after trauma induction.

Results: CCI led to diffuse, asymmetric and bilateral disturbances of both static and dynamic parameters in the CatWalk XT® gait analysis. The CatWalk XT® detected even minimal but statistically significant impairments that could not have been detected by clinical assessments. Impairments of static parameters were most pronounced within the first three days and diminished thereafter, while dynamic parameters were impaired until seven days after CCI. Fittingly, mice explored the hole board significantly less on day three trauma induction.

Conclusions: The CatWalk XT® is a valid tool for objective assessment of motor function in the acute phase after controlled cortical impact TBI in mice. Similar to observations made in humans, CCI leads to impairments of both static and dynamic parameters of gait and motor function which persist throughout the first week after the injury.

Keywords: Automated gait analysis; Behavior; Behavioral test; CCI, controlled cortical impact; CatWalk XT®; CatWalk®; Gait; TBI, traumatic brain injury; motor function.