Recent advances in lower-extremity exoskeletons in promoting performance restoration

Lower-Extremity Exoskeletons (LEEs) are mechanical devices used to assist or resist users' leg motion. It has evolved as performance restoration intervention devices for abnormal gait due to various neuromuscular disorders. The initial evolution of LEEs aimed at developing robust controllable platforms providing fixed trajectory training. Recently, more emphasis has been on introducing human-robot interaction components through advances in intervention strategy, structural design, and controller architecture to promote active user participation and LEEs' applicability for effective rehabilitation. This review highlights that the ongoing advancements in LEEs have been to incorporate the principles of human anatomy, user intention, and positive functional recovery outcome for performance restoration. It presents recent studies to underline the ongoing coalition of gait neuromechanics, motor recovery, and plasticity with the robotic science of LEEs. In conclusion, it is opined that emphasizing longitudinal studies with intensive task-specific training and patient participation strengthens this coalition to impact patients with mobility impairment.