Skilled reach training enhances robotic gait training to restore overground locomotion following spinal cord injury in rats

• Published in: Behavioural brain research Vol. 414; p. 113490
• Main Authors: Neckel, Nathan D., Dai, Haining, Hanckel, John, Lee, Yichien, Albanese, Christopher, Rodriguez, Olga
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 24-09-2021
• Subjects: Animals; Behavior, Animal - physiology; Diffusion Tensor Imaging; Disease Models, Animal; Gait Disorders, Neurologic - diagnostic imaging; Gait Disorders, Neurologic - etiology; Gait Disorders, Neurologic - pathology; Gait Disorders, Neurologic - rehabilitation; Humans; Motor Activity - physiology; MRI; Neurological Rehabilitation; Rats; Reach training; Robotic gait training; Robotics; Spinal Cord Injuries - complications; Spinal Cord Injuries - diagnostic imaging; Spinal Cord Injuries - pathology; Spinal Cord Injuries - rehabilitation; Spinal cord injury; Spinal cord injury; MRI; Robotic gait training; Reach training
• ISSN: 0166-4328; 1872-7549
• DOI: 10.1016/j.bbr.2021.113490

•Robot assisted gait training partially reduced the locomotor deficits following a C4/5 overhemisection injury in rats.•Greater recovery was observed when robot assisted gait training was done in conjunction with skilled forelimb training.•MEMRI imaging of the spinal cord indicated that there was no increase in the number of active cells around the injury site.•DTI suggested an increase in collateralization at the injury in rats that received reach and robot assisted gait training
Rehabilitative training has been shown to improve motor function following spinal cord injury (SCI). Unfortunately, these gains are primarily task specific; where reach training only improves reaching, step training only improves stepping and stand training only improves standing. More troublesome is the tendency that the improvement in a trained task often comes at the expense of an untrained task. However, the task specificity of training does not preclude the benefits of combined rehabilitative training. Here we show that robot assisted gait training alone can partially reduce the deficits in unassisted overground locomotion following a C4/5 overhemisection injury in rats. When robot-assisted gait training is done in conjunction with skilled forelimb training, we observe a much greater level of recovery of unassisted overground locomotion. In order to provide reach training that would not interfere with our robotic gait training schedule, we prompted rats to increase the use of their forelimbs by replacing the standard overhead feeder with a custom made, deep welled hopper that dispensed nutritionally equivalent small milled pellets. We speculate that the increase in recovery from combined training is due to a more robust interneuronal relay network around the injury site. in vivo manganese-enhanced magnetic resonance imaging of the spinal cord indicated that there was no increase in the cellular activity, however ex vivo diffusion tensor imaging (DTI) suggested an increase in collateralization around the injury site in rats that received both reach training and robot assisted gait training.