The CatWalk gait analysis in assessment of both dynamic and static gait changes after adult rat sciatic nerve resection

Functional repair of neurotmesis has been proven most challenging in regenerative medicine. Progress in this field has shown that functional repair not only requires axon regeneration, but also selectivity in target reinnervation. Although selectivity in target reinnervation still involves relatively unexplored avenues, evidence-based medicine, in the end, requires behavioral proof of repair. Therefore, there is a need for tests assessing behavioral deficits after neurotmesis. To date, behavioral tests for detecting both dynamic and static parameters are limited. The CatWalk gait analysis has been shown to detect a multitude of speed-controlled dynamic and static gait deficits after experimental spinal cord injury. Therefore, we here evaluated its use in detecting both dynamic and static gait deficits after neurotmesis. After rat sciatic nerve resection CatWalk testing was performed for 8 weeks. A large amount of dynamic and static gait parameters were detected to be immediately and severely affected in the ipsilateral paw, sometimes reaching levels of only 15% of those of the unaffected paw. We conclude that the CatWalk objectively detects dynamic and static gait impairments after sciatic nerve resection and future experiments are now required to prove which of these parameters are of particular interest to detect functional repair.