Trunk muscle activity patterns in a person with spinal cord injury walking with different un-powered exoskeletons: A case study

Objective: To investigate trunk muscle activity patterns in a person with thoracic spinal cord injury when walking with different un-powered exoskeletons, and to explore how different un-powered exoskeletons affect trunk muscle activity patterns. Case report: Data were recorded from a subject with complete spinal cord injury at T10, using an electromyography system on 4 pairs of trunk muscles and a motion capture system simultaneously. Results: The participant generated large muscle force to laterally bend and rotate trunk, and swung his leg through the moments generated, not only by trunk flexion and extension, but by trunk rotation. In an energy-stored exoskeleton without springs condition, the energy generated by erector spinae contraction was stored in the energy-stored component in the stance phase and released in the swing phase to compensate for energy generated by the obliquus externus abdominis and avoid overuse of the obliquus externus abdominis. Conclusion: These findings prompt further development of un-powered exoskeletons and investigation into trunk muscle functions in patients with spinal cord injury when walking with un-powered exoskeletons.