The development of rehabilitative devices has seen another milestone at Hong Kong Polytechnic University (PolyU). Specifically intended for stroke patients with hemiplegia, the Mobile Ankle-foot Exoneuromusculoskeleton is a first-of-its-kind multimodal robot for ankle-foot therapy that enhances lower limb motor function and walking capacity.
About 50,000 new occurrences of stroke are reported to occur in Hong Kong each year, and 85% of patients have some degree of reduced physical mobility. Regaining physical mobility after a stroke is essential for reducing symptoms like impairment. This can be achieved by consistent, rigorous, and repeated rehabilitation training. Accessing daytime outpatient rehabilitation services at nearby hospitals and rehabilitation clinics is difficult, nevertheless, because of the high demand. As a result, stroke victims frequently find it difficult to engage in regular, timely rehabilitation exercises.
Foot drop and inversion are common functional deficits among stroke patients that cause major disruptions to their daily lives. The Mobile Ankle-foot Exoneuromusculoskeleton is a novel multimodal wearable robot for ankle-foot rehabilitation that combines the benefits of the exoskeleton, soft pneumatic muscles, tactile sensory feedback, and neuromuscular electrical stimulation technology in one system. The research team behind this innovative device is led by Dr. Hu Xiaoling, Associate Professor in the Department of Biomedical Engineering at PolyU. Not only can the gadget efficiently address foot drop and foot inversion, but it can also help stroke patients walk more naturally. Furthermore, it can enhance walking balance and, over time, support rehabilitative neuroplasticity, reports Mirage.
Hemiplegic stroke patients typically have impaired muscle strength and impaired motor function at the affected lower extremity, particularly in the foot and ankle. The gait events of patients, such as standing, heel strike, heel off, and toe-off, can be automatically detected by the Mobile Ankle-foot Exoneuromusculoskeleton. With mechanical support from the exoskeleton and soft pneumatic muscles, the device can help a patient stand firmly on their affected foot. It can also improve foot drop by teaching the patient how to balance their plantar pressure and exert propelling force when walking through vibration tactile feedback and neuromuscular electrical stimulation.
Because of its lightweight design and sporty features, the400g Mobile Ankle-foot Exoneuromusculoskeleton is more appropriate for hemiplegic patients to use unilaterally on their own. Patients can practice any time, any place—at home, outdoors, or indoors—with this device's minimal power consumption and four-hour continuous use period on a 9V rechargeable battery. There are other exoskeleton lower-limb robots on the market, but they are not very useful in helping stroke patients with hemiplegia improve their ankle joint and muscle coordination because they only use external force to help patients walk. The high weight and power consumption of these robots also restrict their use in medical facilities such as hospitals and rehabilitation centers. Conventional ankle-foot orthoses have the potential to induce atrophy in the muscles and hinder patients' ability to regain voluntary motor control over the affected leg's ankle.
Dr Hu stated, "Combining the research capabilities of the Department of Biomedical Engineering, Industrial Centre, School of Fashion and Textiles, and Department of Computing, the Mobile Ankle-foot Exoneuromusculoskeleton is a testament to PolyU's exceptional strength in interdisciplinary research. This research achievement provides stroke patients a better option for lower limb rehabilitation training, incorporating the training into their daily activities. It also enables therapists to provide tele-supervision of the rehabilitation progress of multiple patients. We hope such flexible self-help training can effectively supplement traditional outpatient rehabilitation services, helping stroke patients achieve more efficient rehabilitation progress."