A Wearable Ankle Ligament Relaxation Monitoring System Based on a Porous Graphene Strain Sensor

Chronic ankle instability (CAI) refers to the phenomenon of frequent ankle sprain caused by damage to ligaments around the ankle, which has a very high incidence in the sports population with great negative effect on people’s daily life. The physical diagnosis of CAI is mainly based on the degree of ankle ligament relaxation (ALR), but the widely used anterior drawer test (ADT) mainly relies on the experience of doctors and unquantifiable, leading to high incidence of misdiagnosis. In this work, a biomimetic porous graphene-SBR (styrene-butadiene rubber) strain sensor (PGSSS) with a high gauge factor (210), a wide measuring range (90%), and high durability (10,000 stretching cycles) is designed and integrated into a wearable system to monitor, process, transmit, and display ankle skin strain data for ALR analysis in real-time. The PGSSS-based wearable system can accurately monitor ALR, which is of great significance for accurate diagnosis and efficient rehabilitation of patients suffering from CAI.