Augmented Implanted Orthopedic Fixators with an Embedded Temperature Sensor for Early Detection of Deep Infections

The implantation of foreign orthopedic devices in the human body can introduce potential complications, including the risk of infection. In line with the emerging trend of cyber prostheses, this study aims to transform an orthopedic fixator used for foot malformations into a data generator using passive RFID technology in UHF band. The metal nail was modified to serve as an antenna, taking the form of an unbalanced dipole. This antennified fixator allows for reading by a standard UHF RFID reader with a power margin of 2.3 W EIRP from a distance of 10 cm from the skin. A preliminary prototype was constructed and subjected to electromagnetic and thermal characterization. The results demonstrated the feasibility of wirelessly detecting temperature variations near the implant site, which are indicative of infection onset. This promising outcome highlights the potential for early infection detection using the proposed approach.