Clinical Investigation to Validate the Safety and Performance of Integrating Functional Electrical Stimulation Into the ABLE Exoskeleton

This is a pre-post, single-centre, quasi-experimental study with an estimated duration of 16 weeks. The study will be conducted at therapy2people GmbH (Vienna, Austria). A minimum of 15 participants (5 per subgroup: spinal cord injury, acquired brain injury, multiple sclerosis) will be recruited within a period of up to 8 weeks. After providing informed consent, participants will undergo a screening visit to confirm eligibility based on predefined inclusion and exclusion criteria. At the latest, one week after screening, participants will complete a baseline assessment. The intervention will consist of 8 gait training sessions with the ABLE Exoskeleton with Functional Electrical Stimulation integration(ABLE FES), performed twice per week over 4-5 weeks. Each session will last approximately 60 minutes and include donning/doffing, walking training, and safety/performance assessments. Electrode placement and stimulation parameters will be adapted to the participant's neurological condition. Outcome measures will focus on device safety (adverse events, serious adverse events, withdrawals) and clinical performance (donning/doffing time, walking distance, number of steps, standing time, therapist assistance, gait parameters, and motor torque). Additional measures will include lower limb spasticity, pain, perceived exertion, user satisfaction, and tolerance to FES. For safety monitoring during sessions involving functional electrical stimulation (FES) with the exoskeleton, vital signs including heart rate and blood pressure will be measured before, during, and after the intervention sessions. At the latest, one week after the last training session, a post-training assessment will be conducted. Two weeks later, participants will return for a follow-up visit to record any adverse events since the end of training. This study will provide valuable evidence on the safety, feasibility, and potential rehabilitation benefits of integrating functional electrical stimulation into a robotic exoskeleton for patients with neurological gait impairments.