Advances in flexible wearable pressure/strain sensors for motion monitoring in orthopaedic sports medicine

The growing demand for real-time, high-resolution motion monitoring in orthopaedic sports medicine is driving the development of flexible wearable pressure/strain sensors. These devices, which transduce mechanical stimuli into electrical signals via piezoresistive, capacitive, piezoelectric, electromagnetic, and triboelectric mechanisms, enable continuous biomechanical data acquisition in dynamic, real-world settings, thereby overcoming the limitations of traditional lab-based methods. This review provides a comprehensive overview of recent advances in wearable pressure/strain sensors, covering fundamental sensing mechanisms and innovative design strategies, including using elastomers, polymer thin films, electronic textiles, and hydrogels. The review also highlights key emerging trends, such as microstructured, bioinspired, multimodal, and machine-learning-enabled signal-processing designs, which have significantly enhanced sensor performance by addressing challenges such as limited sensitivity, narrow detection range, environmental interference, and long-term instability. These sensors are now integrated into wearable devices with diverse applications in orthopaedic sports medicine, including real-time motion tracking, gait analysis, injury prediction and diagnosis, rehabilitation assessment, and human-machine interaction. This review also deliberates on existing limitations and delineates future directions for translating wearable pressure/strain sensors into practical orthopaedic sports medicine applications. To address the limitations of traditional lab-bound motion monitoring, such as high costs and restricted environments, it is essential to leverage the progress in flexible wearable sensing technology. This review provides a comprehensive overview of recent advancements in wearable pressure/strain sensors, highlighting their role in capturing high-resolution biomechanical data in real-world settings. By enabling continuous motion monitoring and objective assessment, these advancements offer valuable insights to improve clinical outcomes in orthopaedic sports medicine, with significant translational potential.