Innovations in Orthotic Devices: Additive Manufacturing, Auxetic Materials and Smart Sensors for Enhanced Rehabilitation

Orthoses are external devices designed to provide structural and functional support for disorders affecting the musculoskeletal or nervous systems. While these devices have a long history, recent technological advancements offer significant opportunities to enhance their therapeutic performance. This review examines three key innovations shaping the future of orthotic devices: additive manufacturing, auxetic metamaterials, and smart sensors. Additive manufacturing (AM), commonly known as 3D printing, is gaining prominence for its ability to create patient-specific solutions, improve design flexibility, and reduce production time. Despite these advantages, traditional fabrication methods remain dominant due to cost and regulatory challenges. Auxetic metamaterials, characterized by a negative Poisson’s ratio, allow an orthosis to dynamically conform to the patient’s anatomy and movements while maintaining stability and comfort. Thanks to synclastic deformation, auxetic structures reduce the formation of wrinkles during motion, improving body fit, and potentially enhancing comfort as well as adherence to orthosis usage recommendations. However, their integration into orthoses is still in the early stages, requiring further research and clinical validation. Finally, smart sensors have been extensively studied for the real-time monitoring of joint movement and rehabilitation progress, enabling personalized therapy and improved clinical outcomes. In conclusion, these emerging technologies—additive manufacturing, auxetic metamaterials, and smart sensors—hold great promise for next-generation orthotic devices, but widespread adoption will depend on addressing technical, economic, and practical limitations.