ZEPU-AI3 Lower Limb Feedback Robot Training Study

Inclusion Criteria: * • Lower-limb motor dysfunction from one of the following: (a) stroke (onset 2-24 months), (b) incomplete spinal-cord injury (neurological level T12 and below, ASIA C or D), (c) orthopedic surgery (e.g., knee/hip replacement) with persistent gait impairment \> 3month post-surgery. Stroke onset between 2-24 months ensures inclusion of individuals in the subacute to chronic phase, where gait recovery is still achievable and measurable. Incomplete SCI targets individuals with partial motor preservation, who are capable of engaging in active gait training with robotic assistance. * Age \>18 and ≤ 60 years. This age limit is chosen because individuals with this age range generally have better cardiopulmonary reserve and musculoskeletal tolerance, allowing safer participation in intensive robotic-assisted training with reduced risk of adverse events. Excluding younger patients minimizes heterogeneity related to growth, neurodevelopmental factors and congenital disorders, which may influence gait mechanics and response to robotic therapy. Excluding older adults (\>60 years) helps reduce confounding from age-related degenerative changes that may affect gait outcomes and safety. * Able to provide informed consent and understand instructions which ensures participants can actively engage in therapy, follow safety instructions and report adverse events. * Weight ≤ 100 kg (as per device spec) and height within device adjustable range (manufacturer spec). Exceeding weight or height limits may compromise mechanical support, safety, and accurate gait training. * Medically stable and cleared by physician for exoskeleton use (no active infection, uncontrolled cardiac/respiratory disease, severe osteoporosis, uncontrolled epilepsy, untreated DVT) through pre-screening with necessary investigations. Exclusion Criteria: * • Complete spinal cord injury with inability to bear any weight as it requires the patient to actively support some body weight or participate in stepping movements. * Severe cognitive impairment (e.g., MMSE \< 24) preventing safe participation. * Severe spasticity (Modified Ashworth Scale \> 3) in lower limbs. High muscle tone or rigidity increases risk of joint strain, skin injury and falls during robotic-assisted training. * Unstable fractures, severe hip/knee contractures (\> 30° fixed flexion), severe osteoarthritis requiring imminent surgery. They can pose high risk for injury during weight-bearing or gait cycles. * Uncontrolled cardiac arrhythmia, pacemaker incompatibility or implanted electronic device incompatible with robot sensors. Individuals with these conditions may face elevated risk of adverse cardiac events or device malfunction. * Pregnancy as safety data for robotic exoskeleton use in pregnant individuals are lacking.